Australian Journal of Crop Science   AJCS

December 2018 | EARLY VIEW | 12(12) 2018 | doi: 10.21475/ajcs.18.12.12

Chlorophyll content, water relation traits and mineral ions accumulation in soybean as influenced by organic amendments under salinity stress

Jannatul Ferdous, M.A. Mannan*, M.M. Haque, M.A.A Mamun, M.S. Alam

Bangladesh Jute Research Institute, Dhaka, Bangladesh
Department of Agronomy, Bangabandhu Sheikh MujiburRahman Agricultural University, Gazipur-1706, Bangladesh
Department of Soil Science, Bangabandhu Sheikh MujiburRahman Agricultural University, Gazipur-1706, Bangladesh


Abstract
The pot experiment was conducted to assess the effect of organic amendments to improve leaf chlorophyll and water content as well as mineral ions accumulation in BARI soybean 5 under saline condition. Two types of organic amendments i. water hyacinth compost ii. rice husk biochar were mixed in soil at 5 tha-1 and 10 tha-1 of both. Irrigation was done with 50 and 100 mM saline solution from 14th days after sowing (DAS) to maturity, where control plants were irrigated with tap water. Data on chlorophyll content, exudation rate, relative water content (RWC), water retention capacity (WRC) in leaf were measured at flowering stage as well as Na, K, Ca, Mg and Na: K ratio in leaf and stem were also recorded at harvest. Results revealed that salinity decreased chlorophyll content, exudation rate, relative water content, water retention capacity and K, Ca, Mg content in leaf and stem of soybean plant. Water hyacinth compost and rice husk biochar had positive effects to mitigate negative effects of salinity on soybean plant. However, rice husk biochar at 5 tha-1 showed best result to mitigate salinity stress on soybean at low salinity (50 mM) condition.

Pages 1806-1812 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p942
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Growth and yield response of maize to rice husk biochar

Shaon Md. Jahidul. Islam1, M.A. Mannan*, Q.A. Khaliq, M. M. Rahman

Department of Agronomy, Bangabandhu Sheikh MujiburRahman Agricultural University, Gazipur-1706, Bangladesh
Department of Soil Science, Bangabandhu Sheikh MujiburRahman Agricultural University, Gazipur-1706, Bangladesh


Abstract
Globally, the current important concern is to waste minimization by producing biochar for crop production. The experiment was conducted at the research field from November 2015 to March 2016 to assess the growth and yield of maize (BARI Hybrid Bhutta 9) under variable rice husk biochar levels. The rice husk biochar levels 0, 1.5, 3, 5 and 7 t ha-1 constituted the treatment variables. Results revealed that growth and yield of maize were significantly influenced by different doses of rice husk biochar. Highest internodal length, stem diameter, leaf area index (LAI), crop growth rate (CGR), dry matter accumulation, grain yield and lowest net assimilation rate (NAR) were found when soil was treated with rice husk biochar @ 7 t ha-1 than in the biochar doses of @ 5, 3, 1.5 t ha-1 as well as 0 t ha-1 (Control). It was found that biochar increased soil pH from strongly acidic to slightly acidic. Biochar was found efficient in increasing soil organic carbon, nitrogen and sulphur and decreasing soil bulk density to favorable level. We concluded that the application of biochar increased growth and grain yield of maize and improved chemical and physical properties of soil.

Pages 1813-1819 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p944
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Genetic diversity of maize lines for traits related to maturity and yield components

Élcio Friske*, Adilson Ricken Schuelter, Ivan Schuster, Jonatas Marcolin, Mayara Fabiana da Silva

Universidade Estadual do Oeste do Paraná, Marechal Cândido do Rondon-PR, Brazil
Cooperativa Central de Pesquisa Agrícola, Cascavel-PR, Brazil


Abstract
Grain yield and maturity class are among the commercial traits that most often direct maize breeding that aims to meet the requirements of the seed market. Thus, the aim of this study was to evaluate genetic diversity in maize inbred lines for grain maturity and yield components. The phenotypic attributes of 81 maize inbred lines were assessed in a field experiment in a square lattice design with three replications. Analysis of variance and multivariate analysis were performed considering complete randomized blocks due to the equivalence to the estimation for lattice efficiency. The results of analysis of variance indicated genetic diversity in the germplasm for all the traits, showing high variability for number of days to male flowering (DMF) and female flowering (DFF). Genetic diversity was also detected for grain water loss, which was determined by the area under the water loss curve (AUWLC), an index representing the dynamic progress of field water loss, based on area under the disease progress curve (AUDPC). The high magnitude of genetic correlation between the AUWLC and the moisture content of grain (0.98) collected at different moments in the R6 stage suggests the possibility of its substitution by the moisture content evaluation in only one collection. Weak genetic correlations (0.07 to 0.45) between yield and maturity components indicated the possibility of selection for earliness without compromising yield. In addition, the results of the Tocher method and the UPGMA were compatible, enabling classification of the germplasm and suggestion of hybrid combinations among inbreds that might have a higher heterotic effect on yield associated with earliness.

Pages 1820-1828 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1005
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Assessment of the Tephrosia toxicaria essential oil on hatching and mortality of eggs and second-stage juvenile (J2) root-knot nematode (Meloidogyne enterolobii and M. javanica)

Francisco José Carvalho Moreira, Beatriz de Abreu Araújo, Francisca Gleiciane do Nascimento Lopes, Antonio de Assis Lopes de Sousa, Antônio Evami Cavalcante Sousa, Lucia Betânia da Silva Andrade, Adriana Ferreira Uchoa

Postgraduate Biotechnology Program (RENORBIO/UFRN), Natal, RN, Brazil
Phytosanitary and Seeds Laboratory, Natural Resources Axis, Federal Institute of Education, Science and Technology of Ceará, IFCE - Campus Sobral, Sobral, CE, Brazil
Natural Resources Axis, Federal Institute Goiano, IFGO - Campus Ceres, Ceres, GO, Brazil
Laboratory of Experimental Biology, Center for Agrarian and Biological Sciences, State University of Vale do Acaraú (UVA), Sobral, CE, Brazil
Cellular Biology and Genetics Department, Bioscience Center, Federal University of Rio Grande do Norte (UFRN) Natal, RN, Brazil


Abstract
The search for alternative biocontrol methods is necessary. Several molecules with nematicidal effect have already been identified from plant tissues. They can be considered as important alternative for nematode control. Therefore, the objective of this study was to assess the effect of essential oil of Tephrosia toxicaria on hatching and mortality of second-stage juvenile (J2) root-knot nematode and eggs of Meloidogyne enterolobii and M. javanica. For this purpose, 50 eggs/J2 were incubated with the essential oil of T. toxicaria at seven concentrations (0.0, 50, 100, 200, 400, 600 and 800 μl.mL-1) with six replicates in 48-well acrylic plates. The number of eggs and juveniles were counted with the aid of camera under a stereoscopic microscope. The analysis of the J2 hatch was performed using the area below the hatching progress curve (ABHPC), calculated by the equation proposed by Campbell and Madden. The J2 mortality rate was carried out concomitantly with the hatching observations, 48 hours and also 16 days after applying the treatments. In the evaluations, all the motionless J2 were counted after 48 hours. To confirm the occurrence of mortality, the specimens were transferred to water, then examined in slides, under an optical microscope at a 40x magnification. The data were submitted to analysis of variance using the F-test and the averages were compared by the Skott-Knott test (p≤0.01). We confirmed that the essential oil of T. toxicaria has effectiveness to reduce juvenile hatching and cause J2 mortality in all the assessed concentrations, demonstrating the nematicidal potential of the active principles present in T. toxicaria. The results of this study show that the T. toxicaria essential oil and its constituents can serve as an environmentally safe and a promising nematicide agent in the control of Meloidogyne spp.

Pages 1829-1836 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1102
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Effect of lighting spectrum and naphthaleneacetic acid (NAA) on in vitro development of cactus pear [Opuntia ficus-indica (L.) Mill]

Selma Silva Rocha*, Luciana Cardoso Nogueira Londe, Jessica Guerra Calaes, Júlio Cesar Gomes Pereira, Marcela Caroline Batista da Mota, Wander Silva Viana, Renata Aparecida Neres Faria, Núbia Nunes Xavier

Universidade Estadual de Montes Claros, Janaúba- MG, Brazil
Empresa de Pesquisa Agropecuária de Minas Gerais, Unidade Regional Epamig Norte de Minas, Nova Porteirinha- MG, Brazil
Universidade Federal de Minas Gerais, Montes Claros- MG, Brazil
Engenheiro Agrônomo, Universidade Estadual de Montes Claros, Janaúba- MG, Brazil
Universidade Federal de Lavras, Lavras-MG, Brazil
Universidade Estadual de Montes Claros, Janaúba- MG, Brazil
Engenheira Agrônoma, Universidade Estadual de Montes Claros, Janaúba- MG, Brazil
Universidade Estadual de Montes Claros, Janaúba- MG, Brazil


Abstract
Modification of in vitro culture environment can improve the development of plants, obtaining higher morphological and physiological quality. The objective of this work was to analyze the influence of different luminous spectrums as well as different doses of auxin NAA on in vitro development of cactus pear (Opuntia ficus-indica (L.) Mill). The experiment was conducted in a completely randomized design in factorial scheme 4 x 3 (Luminous spectrums x NAA doses), corresponding to four luminous spectrums: red, green, blue and white, and three doses of NAA 1, 2 and 3 mg. L-1. A total of 12 treatments with 6 replications were applied including 1 plant per repetition. Cactus pear plants were introduced on MS culture medium solidified with 7% agar, and pH adjusted to 5.8. We observed higher development of plants (growth and rooting) under luminous spectrums, 30 and 60 days after plant establishment (red and green). At concentrations of 1 and 2 mg L-1 of NAA we observed better height of the plants, 30 and 60 days after establishment. The luminous spectrums red and green influenced the in vitro development of cactus pear plants. The best doses to promote better plant growth are 1 and 2 mg. L-1 of NAA.

Pages 1837-1843 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1104
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Chemical and physical treatments can change the germination and seed vigor of crambe (Crambe abyssinica Hochst). A case study

Gisele Silva de Aquino*, Marita Di Loreto Y. Sampaio, Tatiane Lobak, Cristiane de Conti Medina, Adônis Moreira

Department of Agronomy, Universidade Estadual de Londrina, Rod. Celso Garcia Cid, PR 445, Km 380, Box-Postal 10.001, CEP 86057-970 Londrina, Paraná, Brazil
Departamento de Ciência de solo da Empresa Brasileira de Pesquisa Agropecuária, EMBRAPA, Londrina, PR, Brazil


Abstract
Crambe is an oleaginous plant with a high oleic content and a high potential for biodiesel production, offering important alternatives for farmers. Its seeds have a tegument structure (pericarp), which limits the uniformity of germination, and consequently, the plant height. This paper evaluates seed germination and vigour of crambe seeds under the influence of physical and chemical treatments. The treatments were arranged in a 3 x 3 factorial scheme (three physical treatments × three chemical treatments) with four replicates of 50 seeds each. Physical treatments were as follows: intact seeds (no scarification), mechanically scarified seeds and chemically scarified seed. The chemical treatments consisted of the application of gibberellic acid (GA3 – 50% concentration), potassium nitrate (KNO3 – 0.2% concentration) and water. The traits evaluated were germination (%), germination speed index (GSI), seedling number, normal seedling shape, and seedling length and dry mass. The number of seeds germinating over a period of seven days was evaluated daily, and germination was considered effective when a 2-mm long radicle was observed. The physical treatments, when associated with gibberellic acid, resulted in a greater germination potential of the seeds, a higher GSI and a higher index of normal seedlings. The application of gibberellic acid (50% concentration) for seed imbibition at 25oC as pre-germination treatment promoted a higher percentage of crambe seed germination and increased the biometric parameters of the seedlings.

Pages 1844-1848 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1118
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Multivariate analysis of morphological variation in enset (Ensete ventricosum (Welw.) Cheesman) reveals regional and clinal variation in germplasm from south and south western Ethiopia

Zerihun Yemataw*, Kassahun Tesfaye, Murray Grant, David J. Studholme and Alemayehu Chala

Areka Agricultural Research Center, P.O. Box 79, Areka, Ethiopia
Department of Microbial, Cellular and Molecular Biology, Addis Ababa University, Addis
Ababa, Ethiopia
Addis Ababa University, Institute of Biotechnology, P.O. Box 1176, Addis Ababa, Ethiopia
Ethiopian Biotechnology Institute, Ministry of Science and Technology, P.O. Box 32853, Addis Ababa, Ethiopia,
Life Sciences, University of Warwick, Coventry, CV4 7AL. United Kingdom
Biosciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter EX4 4QD, United Kingdom
Hawassa University, College of Agriculture, P.O. Box 05, Hawassa, Ethiopia


Abstract
Enset (Ensete ventricosum (Welw.) Cheesman) is cultivated by millions of people across Ethiopia in diverse agro-ecological and cultural settings, selecting for various agronomic traits. However, as for other underutilized crops, our understanding of the diversity and utilization of enset remains limited. This work sought to redress this limitation by estimating morphological diversity among enset accessions collected from major enset growing regions, including across altitudinal gradients. In total, landraces comprising 387 accessions originating from nine regions of Ethiopia were characterized using multivariate analysis of 15 quantitative traits. Cluster analysis grouped accessions in to five distinct classes with maximum number of accessions 338 in cluster (I) and minimum 1 in cluster (V). The clustering of accessions did not show grouping on the basis of region of origin. The first four principal components accounted for ~74% of the total variance. Linear discriminant analysis indicated that around 40.8% (160 accessions) and 45.2% (175 accession) of the studied accessions were correctly classified to their respective regions of origin altitude groups, respectively. The breadth of phenotypic differences in these 15 traits suggests significant degrees of genetic variation. These traits will be exploited to identify potential donors for future enset improvement efforts.

Pages 1849-1858 | Full Text PDF| Supplementary Data PDF| Supplementary Data .xls| doi: 10.21475/ajcs.18.12.12.p1135
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Genetic variation and relationships of total seed protein content with some agronomic traits in pigeonpea (Cajanus cajan (L.) Millsp.)

Jimmy Obala, Rachit K. Saxena*, Vikas K. Singh, Suryanarayana Vechalapu, Roma Das, Abhishek Rathore, Chanda V Sameer-Kumar, Kulbhushan Saxena, Pangirayi Tongoona, Julia Sibiya, Rajeev K. Varshney

International Crops Research Institute for the Semi-Arid Tropics, Patancheru 502 324, Hyderabad, India
University of KwaZulu-Natal, Pietermaritzburg, South Africa


Abstract
Seed protein content (SPC) is an important grain quality trait, which impacts the nutritional importance of pigeonpea seed in the diet of over a billion people globally. The present study was carried out to determine variation in SPC and its relationships with some agronomic traits among 23 parental lines of different types of pigeonpea mapping populations. The parental lines were evaluated under field conditions during 2014-2015 growing season. A randomised complete block design in two replications was used. Data were recorded on SPC, days to first flower (DTF), plant height at maturity (PltH), number of pods per plant (NPP), number of seeds per pod (NSP), hundred-seed weight (SW) and seed yield per plant (SY). There were significant differences among genotypes for all traits. Broad-sense heritability was 0.693 for SPC but ranged from 0.519 (NPP) to 0.999 (DTF) while genetic advance was 2.4% for SPC but ranged from 1.2 % (NSP) to 141.2 % (SY), and genetic gain ranged from 11.0 % (SPC) to 230.0 % (SY). Simple correlation showed that SPC is only significantly but negatively correlated with SW (r = -0.30, P < 0.05), while path analyses revealed that SPC is negatively associated SW and NPP but positively with DTF, PltH, NSP and SY. It is concluded that genetic variation for SPC and agronomic traits exist among pigeonpea genotypes studied. The variation is accompanied by both favourable and unfavourable relationships of SPC with the agronomic traits.

Pages 1859-1865 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1138
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Yield and biometry of palisadegrass throughout the seasons of the year

Débora Pantojo de Souza*, Arthur Carniato Sanches, Fernanda Lamede Ferreira de Jesus, Fernando Campos Mendonça

Agricultural Systems Engineering, Escola superior de Agricultura “Luiz de Queiroz” (ESALQ/USP), CEP: 113418-900, Piracicaba, São Paulo, Brazil
Agricultural Systems Engineering, ESALQ/USP, CEP: 113418-900, Piracicaba, São Paulo, Brazil


Abstract
Tropical forage crops present different productive behavior during climatic seasons, because meteorological elements significantly influence the increase or decrease of their forage production and some plant biometric parameters. This work aimed to characterize productive and phytotechnical parameters of palisadegrass under two cultivation systems, single cropped and intercropped (black oats plus ryegrass) during four seasons of one-year period. The experiment was carried out at ESALQ/USP, under a completely randomized statistical design, in two experimental plots with individual area of 144 m². Irrigation was applied by a sprinkler system with a spacing of 12×12 m. The parameters evaluated were: total forage yield, leaf-stem ratio, final leaf area index (LAIfinal), leaves yield, stems yield, dead material yield, and the mass percentages of leaf, stem and dead material. All over the cycle, the leaf area index (LAI) and canopy height (CH) parameters were measured and correlated with degree-days. The statistical analysis was performed using ASSISTAT 7.7 software. The results showed that the maximum forage yield of single cropped palisadegrass (summer and winter) was 4951.5 and 1318.7 kg DM ha-1. The comparison between the sum of yield in all overseeded cropping cycles (4th IS to 8th IS) and the sum of yield in all the single cropping cycles showed a higher yield in the first ones. The LAIfinal also presented similar behavior to the crop yield in the single cropped system all over the year. The estimates for CH and LAI from daily air temperature data (degree-days) improve the management of irrigated pastures.

Pages 1866-1874 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1160
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(S)-(-)-limonene fumigation protects waxflowers (Chamelaucium spp.) from detrimental effects of ethylene on abscission of flowers/buds

Sabah Abdalghani, Zora Singh, Kevin Seaton, Alan Payne

Curtin Horticulture Research Laboratory, School of Molecular and Life Sciences, Faculty of Science and Engineering, Curtin University, GPO Box U 1987, Perth 6845, WA, Australia
Department of Primary Industries and Regional Development, (DPIRD), South Perth, WA, Australia


Abstract
Waxflowers are economically important native cut flowers in Australian floriculture industry. Postharvest flowers/buds abscission on stems of waxflowers causes serious economic losses to the Australian waxflower industry. The effects of (S)-(-)-limonene in reducing the damaging effects of ethylene on abscission of flowers/buds in six varieties of Geraldton waxflowers ‘WX73’, ‘WXFU’ ,‘WX17’, ‘WX58’, ‘WX56’ and ‘Purple Pride’ were investigated in 2014 and 2015. All the experiments were conducted having four treatments. The flowers stems were fumigated with ethylene (10 µLL-1) for 24 h and (S)-(-)-limonene (1 µM) alone for 18 h and (S)-(-)-limonene fumigation followed by exposure to ethylene. Untreated sprigs served as control. All the six experiments were laid out by following two-factor factorial completely randomised design including the (4 treatments and 4 times) with three replications and three stems were treated as an experimental unit. Cumulative abscission of flowers/buds was calculated for four consecutive days following 24 h of ethylene exposure. Fumigation with (S)-(-)-limonene (1 µM) for 18 h followed by exposure to 10 µLL-1 ethylene significantly reduced flowers/buds abscission as compared to ethylene treatment alone in all varieties except ‘WX17’. Mean flowers/buds abscission was significantly reduced when flower stems were fumigated with (S)-(-)-limonene followed by exposure to 10 µLL-1 ethylene (26.7%, 30.9%, 62.4%, 13.6 and 6.4%) as compared to those exposed to ethylene treatment alone (89.9%, 82.0%, 77.4%, 85.9% and 68.8%) in ‘WX73’, ‘WXFU’, ‘Purple Pride’, ‘WX56’ and ‘WX58’ respectively. ‘WX17’ waxflower fumigated with (S)-(-)-limonene followed by exposure to 10 µLL-1 ethylene did not show a significant reduction in flowers/buds abscission as compared to ethylene alone probably this genotype is more sensitive to ethylene because of their inherited trait. The results reveal that (S)-(-)-limonene appears to be acting as an antagonist to ethylene action and consequent reduced flowers/buds abscission in waxflowers.

Pages 1875-1881 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1163
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Respiratory activity and physiological performance of maize seeds classified according to their shapes and sizes

Lucian Alex dos Santos, Carolina Cipriano Pinto, Vinícius Jardel Szareski, Ivan Ricardo Carvalho, Felipe Koch, João Roberto Pimentel, Cristian Troyjack, Ítala Thaísa Padilha Dubal, Fernanda Reolon, Tiago Corazza da Rosa, Ana Karina do Carmo Ferreira dos Santos, Tiago Pedó, Emanuela Garbin Martinazzo, Dario Munt de Moraes, Luis Osmar Braga Schuch, Francisco Amaral Villela, Tiago Zanatta Aumonde

Universidade Federal de Pelotas, CEP 96010-610, Capão do Leão, RS, Brazil
Universidade Federal do Rio Grande, Instituto de Ciências Biológicas, Rio Grande, RS, Brazil


Abstract
The objective of this work was to evaluate the influence of seed size and shape on physiological performance and respiration, as well as to establish the relationship between physiological quality and respiratory activity of maize seeds. For studying the influence of size and shape of the different seed fractions, the following analyzes were performed: weight of one thousand seeds, germination, first germination counting, germination speed index, total seedlings dry mass, electric conductivity, cold test without soil, seeds respiratory activity, seedling emergence and emergency speed index.The data were submitted to analysis of variance, the variables were compared by the Tukey test. Pearson's correlation test was performed between seed shapes and sizes, and the attributes of physiological quality. The small flat seeds from genotype "A" present higher physiological quality than large flat, large round and small round seeds. Whereas, for genotype "B", seeds with the highest physiological quality are the flat shapes, regardless their size. Respiratory activity in both genotypes was not sensitive for detecting differences of vigor between different sizes and shapes. There is significant correlation between large flat seeds, as well as between small flats and large rounds and small seeds with germination speed index. Similarly, there is correlation between the different shapes and sizes with electrical conductivity.

Pages 1882-1889 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1165
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Analysis of genetic diversity of gac [Momordica cochinchinensis (Lour.) Spreng] in Southern Vietnam using fruit-morphological and microsatellite markers

Pham Duc Toan*, Huynh Van Biet, Vo Thi Thuy Hue, Huynh Dang Sang, Bui Minh Tri, Bui Cach Tuyen

Research Institute for Biotechnology and Environment, Nong Lam University, Ho Chi Minh city, Vietnam – Linh Trung ward, Thu Duc district, Ho Chi Minh city, Vietnam
Faculty of Environment and Natural Resources, Nong Lam University, Ho Chi Minh city, Vietnam – Linh Trung ward, Thu Duc district, Ho Chi Minh city, Vietnam


Abstract
Sweet gourd (Momordica cochinchinesis (Lour.) Spreng) (2n = 28) belongs to Cucurbitaceae family and is native to Southeast Asia as well as Vietnam. It is indigenous throughout Asia and being used as food and for medicinal purpose. The aim of this study was to estimate genetic diversity of gac accessions collected from Southern Vietnam based on 7 fruit-morphological traits and 10 SSR markers. The analysis of variance (ANOVA) revealed highly significant differences among 16 gac accessions. The gac accessions revealed difference in all fruit-morphological characters. Ten SSR primers showed high level of polymorphic fragments (100%). A total of 52 alleles were detected and the number of alleles per locus ranged from 2 to 8 with an average of 5.2 alleles per locus. The fragment size varied from 150 bp to 610 bp. The polymorphism information contents (PIC) of markers varied from 0.27 to 0.86 with an average of 0.58. Expected heterozygosity (HE) ranged from 0.11 to 0.86 with a average of 0.40. The mean of observed heterozygosity (HO) was 0.64 with ranging 0.38–0.94. Nei’s genetic distance coefficient ranged between 0.0 and 1.0 and with the mean 0.79. Dendrogram based on UPGMA analysis grouped the 16 gac accessions into three main groups. Combination of fruit-morphological with molecular markers such as microsatellite markers gives a good observation of genetic diversity of gac accessions.

Pages 1890-1898 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1170
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Determination of damage caused by different populations of Diloboderus abderus (Coleoptera: Scarabaeidae) larvae on wheat

Eleodoro E. Del Valle*, Gabriel F. Mayer, Gabriel A. Mazuquín, Pablo Nari, Guillermo D. Toffoli, Horacio O. Imvinkelried

Facultad de Ciencias Agrarias, Universidad Nacional del Litoral, Esperanza, Santa Fe, Argentina
Consejo Nacional de Investigaciones Científicas y Técnicas, Argentina


Abstract
Wheat (Triticum aestivum L.) is the most widely cultivated cereal crop worldwide because it is an important food source for humans. South America has long been associated with wheat production and export. Given the increased application of no till in the last decades, the scarabid Diloboderus abderus has become the main soil pest of this crop. The larvae of this insect (white grubs) feed on roots, causing plant weakening and death. The aim of this work was to determine the relationship between the soil population of D. abderus larvae and the number of established wheat plants. In a plot cultivated with the wheat cultivar Don Mario Algarrobo at a seeding rate of 130 kg ha-1 and with high population levels of this pest, 1-m2 sites with 20-39; 40-60; 80-100; 120-160 and or 200-240 plants were established. At the tillering phenological stage, the number of tillers per plant and of insect larvae in each subplot was counted. The results showed a significant reduction in plant density with increasing soil larval population. The crop counterbalanced the reduction in plant number by increasing the tiller number per unit area. The present work shows that population levels above 11 larvae m-2 generate a significant reduction in the number of wheat plants established in the crop.

Pages 1899-1901 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1193
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Management of foliar application of fungicides to enhance physiological and sanitary quality of soybean seeds

Everton Vinicius Zambiazzi, Adriano Teodoro Bruzi, Maria Laene Moreira de Carvalho, Scheila Roberta Guilherme, Alan Mario Zuffo*, Alan Eduardo Seglin Mendes, Ana Paula de Sales, Flaviane de Oliveira Ribeiro, Mariane Cristina Bianchi, Igor Oliveri Soares, Isabela Maria Monteiro Borges

Department of Agriculture, Federal University of Lavras, 37200-000, Lavras, Minas Gerais, Brazil
Department of Biology Federal University of Lavras, 37200-000, Lavras, Minas Gerais, Brazil
Department of Crop Production, State University of Mato Grosso do Sul, 79540-000, Cassilândia, Mato Grosso do Sul, Brazil


Abstract
Controlling disease in the soybean crop is essential for obtaining high quality seeds and high yield. This leads the producer to increase the number of fungicide applications as a preventive measure. The aim of this study was to evaluate soybean response to increase in the number of foliar applications of different chemical fungicides during crop development to enhance the physiological and sanitary quality of soybean seeds. The experiment was performed in the state of Minas Gerais, Brazil, in two environments (Ijaci and Lavras) in the 2014/15 crop year, with the cultivar BRSMG 850GRR. The field experiment was conducted in randomized blocks in split-plots, with three replications. The plots were composed of the number of applications (0, 1, 2, 3, 4 and 5 times). The applications started at the R1 stage (beginning of bloom), with a 15-day interval to the next application (R1; R1+15d; R1+30d; R1+45d; R1+60d). The split-plots were constituted by the different chemical fungicides (Elatus®, Fox®, Opera®, Orkestra®, and an unregistered product - BAS – 702). Seeds were evaluated soon after harvest and after eight months of storage. The following characteristics were evaluated: seed water content, germination in paper and sand substrates, emergence, emergence speed index, mechanical damage in the sodium hypochlorite test, electrical conductivity, accelerated aging, seed vigor and viability by the tetrazolium test, and seed health, using a completely randomized design. Regardless of which fungicide was used, an increase in the number of foliar applications of fungicides, up to five applications, leads to an increase in the physiological and sanitary quality of soybean seeds, both those newly harvested and those stored for eight months. However, Fox® fungicide (trifloxystrobin + prothioconazole) applied on the leaf during the reproductive stages of the soybean crop brought about the best results in the physiological quality of newly harvested seeds and seeds stored for eight months, as well as in the sanitary quality of newly harvested seeds.

Pages 1902-1910 | Full Text PDF| Supplementary Data PDF| doi: 10.21475/ajcs.18.12.12.p1219
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Breeding for anthracnose (Colletotrichum sublineolum Henn.) resistance in sorghum: challenges and opportunities

Girma Mengistu*, Hussein Shimelis, Mark Laing, Dagnachew Lule

University of KwaZulu-Natal, Private Bag X01, Scottsville 3209, Pietermaritzburg, South Africa
Oromia Agricultural Research Institute, P.O. Box 81265, Addis Ababa, Ethiopia


Abstract
Sorghum [Sorghum bicolor (L.) Moench] is an important cereal crop grown for its diverse uses. Global sorghum production and productivity is affected by various stresses notably by biotic factors such as diseases, weeds and insect pests. Anthracnose caused by the fungal pathogen Colletotrichum sublineolum Henn. (formerly known as C. graminicola [Ces.] G.W. Wilson), grain mold, leaf blight, rust and smut are among the most import diseases of sorghum, while stem borer, shoot fly, termites and birds are notable pests of the crop. Sorghum anthracnose occurs in epidemic proportions under high temperature and humidity conditions causing yield losses reaching up to 50% in susceptible varieties. Sorghum shows considerable genetic variation. A large number of landraces are exploited in breeding for disease resistance and better agronomic performance. This review presents literature on breeding sorghum for anthracnose resistance and associated challenges and opportunities. Information presented in this paper may guide future breeding of sorghum varieties incorporating farmer needs and preferences.

Pages 1911-1920 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1230
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Effect of different gamma radiation doses on the germination and seedling growth of wheat and triticale cultivars

Francisco Javier Di Pane, Silvia Concepción Lopez, Miguel Ángel Cantamutto, Marisa Beatriz Domenech, Mauricio Castro-Franco

Instituto Nacional de Tecnología Agropecuaria INTA, CEI Barrow. Ruta 3 Km 488 (7500) Tres Arroyos – Provincia de Buenos Aires - Argentina
Comisión Nacional Energía Atómica (CNEA). División Aplicaciones Agronómicas, Presbítero González y Aragón 15, B1802AYA - Ezeiza – Provincia de Buenos Aires- Argentina
Estación Experimental Agropecuaria Hilario Ascasubi, Ruta 3 Km 794 (8142) Villarino-Provincia de Buenos Aires-Argentina
Consejo Nacional de Investigaciones Científicas y Técnicas CONICET. Av. Rivadavia 1917 (C1033AAJ), Buenos Aires - Argentina


Abstract
Plan breeding of wheat and triticale in Argentina is based on the objective of improving an individual crop, with respect to resistance to drought stress. The use of gamma radiation holds promise for physiological crop improvement. The objective of this study was to determine and compare the effect of different gamma radiation doses on the germination and seedling growth of Argentine wheat and triticale cultivars. Seeds of wheat cv. Baguette 10 and triticale cv. Espinillo INTA were irradiated at doses of 0, 50, 200, 400, 550, 700, 850 and 1000 Gy s-1. The final germination percentage (FGP), sprout length (SL) and median lethal dose (LD50) were used as metrics of germination, seedling growth and lethal dose, respectively. Two experimental designs were used. First, a completely randomized factorial was used to compare the effect of the doses within species by using ANOVA; second, a completely repeated measures design was used to evaluate the effect of days after germination on plant survival by species using a mixed linear model. The results suggest that at the early germination stage, gamma radiation limited root growth and stem length. The FGP of wheat seeds was significantly affected by gamma radiation at a dose of 550 Gy, whereas triticale seeds were significantly affected at a dose of 700 Gy. The SL of both species was similarly affected at 50 Gy. The stem mortality of wheat and triticale seeds increased at an increasing gamma radiation dose and days after germination. Finally, the LD50 value for wheat and triticale seeds was ~450 Gy. These results might be useful to set a benchmark of the effect of the gamma radiation dose to induce mutations in wheat and triticale seeds from Argentine cultivars.

Pages 1921-1926 | Full Text PDF| Supplementary Data PDF| doi: 10.21475/ajcs.18.12.12.p1251
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Polyphenol content and antioxidant capacity of the skin extracts of berries from seven biotypes of the Greek grapevine cultivar Korinthiaki Staphis (Vitis vinifera L.)

Maritina Stavrakaki*, Katerina Biniari, Ioannis Daskalakis, and Despoina Bouza

Agricultural University of Athens, School of Agriculture, Engineering and Environmental Sciences, Department of Crop Science, Laboratory of Viticulture, 75 Iera Odos, GR-11855, Athens, Greece

Abstract
Τhe polyclonality of a grapevine cultivar plays a significant role in the quality of the viticultural products it yields, especially when age-old grapevine cultivars such as Korinthiaki Staphis are entailed. The aim of the present study was to determine the polyphenol content and antioxidative capacity of the berry skins of seven (7) biotypes -possibly clones of the grapevine cultivar Korinthiaki Staphis (Vitis vinifera L.). For the purposes of the present study, it is worth noting at this point that all seven biotypes had been cultivated in the same geographic location and under the same climate and soil conditions. In view of the study’s aim, the biotypes were studied using high performance liquid chromatography (HPLC) coupled with a diode array detector and spectrophotometer. The results revealed that the levels of both polyphenol content and antioxidant capacity were high in all biotypes. Statistically significant differences between and among the biotypes were duly recorded: (a) Biotype KS15 exhibited a high concentration in total anthocyanins, total flavanols, total flavonoids, acidity, and total soluble solids; (b) biotype KS6 exhibited a high concentration in total soluble solids, total flavanols, epicatechin, procyanidins B1 and B2, trans-resveratrol, and piceid; and (c) biotype KS1 exhibited a high concentration in quercetin, rutin, catechin, epicatechin, trans-resveratrol, and piceid; and the highest concentration in the phenolic aldehyde vanillin. Both polyphenolic content and antioxidant capacity are biotype-dependent. Thus, when striving for products of exceptional quality it is crucial for viticulturists to exploit the appropriate biotypes of Korinthiaki Staphis. Research and results on the studied biotypes suggest that KS15, KS1, and KS6, individually or in combination, are the most suitable ones for the establishment of productive vineyards.

Pages 1927-1936 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1261
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Optimisation of in vitro micropropagation of different date palm cultivars

Ahmed Al-Najm, Steve Brauer, Richard Trethowan, Nabil Ahmad*

Plant Breeding Institute, Faculty of Agriculture and Environment, University of Sydney, 107 Cobbitty Road, Cobbitty, NSW 2570, Australia
The Date Palm Research Center, University of Basrah, Basrah, Iraq
Riverland Date Garden, 376 Gurra Road, Gurra Gurra, SA 5343, Australia


Abstract
Rapid and efficient propagation methods that avoid the use of mutagenic growth regulators are required for date palm breeding and cultivation. The effects of different growth regulators on micropropagation of six female cultivars of date palm including Barhee, Medjool, Khalas, Khadrawi, Nemeishi and River Gem and the male cultivar Jarvis were invstigated. The experiments were conducted in vitro using floral explants of female and male mature inflorescences. Embryogenic callus induction and proliferation were significantly higher (93%) in the woody plant nutrient culture medium (WPM) supplemented with 5mg l-1 Thidiazuron (TDZ). The addition of zeatin to the medium was most effective for shoot regeneration from callus and this enhanced regeneration frequency and the average number of shoots obtained per explant. The highest number of shoots/explant (16) was obtained using 2 mg l-1 zeatin in WPM and WPM with 0.5 mg l-1 GA3 and 2 mg l-1 zeatin enhanced shoot length significantly. Bud initiation and adventitious shoot formation 16 weeks after flower culture was enhanced by WPM supplemented with 1.5 mg l-1 2,4-D and 5 mg l-1 2ip. Sub-culturing of formed buds on a multiplication medium supplemented with 3.0 mg l-1 zeatin and 0.3 mg l-1 NAA produced the highest average number of buds. Adventitious shoot elongation (up to 7.64 cm) was maximized using a WPM medium with 0.5 mg l-1 GA3 and 3 mg l-1 zeatin. Optimum rooting (81%) was achieved when shoots were transferred to a medium with 0.2 mg l-1 NAA. The survival rate was 80% and the plants were subsequently transferred to bigger pots and acclimatized for field planting. No phenotypic differences were observed among the regenerants. This observation was validated using a set of five highly polymorphic iPBS and SSR markers.

Pages 1937-1949 | Full Text PDF| Supplementary Data PDF| doi: 10.21475/ajcs.18.12.12.p1267
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Behavior of neem seedlings (Azadirachta indica) irrigated with saline water in the soil with biofertilizer and drainage

Francisco de Oliveira Mesquita, Rafael Oliveira Batista*, Lourival Ferreira Cavalcante, Fabrícia Gratyelli Bezerra Costa, Antônio Gustavo de Luna Souto, Daniela da Costa Leite Coelho, Ketson Bruno da Silva, Francisco Xavier de Oliveira Filho

Federal University of Cariri, Department of Agronomy, 63.048-080, Crato city, Ceará State, Brazil
Rural Federal University of Semi-arid, Department of Engineering and Environmental Sciences, 59.625-900, Mossoró city, Rio Grande do Norte State, Brazil
Federal University of Paraíba, Department of Soil and Rural Engineering, 58.397-900, Areia city, Paraíba State, Brazil
Rural Federal University of Semi-arid, Department of Agricultural Science and Forestry Science, 59.625-900, Mossoró city, Rio Grande do Norte State, Brazil

Abstract

We studied the behavior for neem seedlings subjected to irrigation water salinity and bovine biofertilizer and soil drainage. An experiment was carried during the period of January to June/2016 in greenhouse with plants grown in pots. The experimental design was a randomized block with factorial scheme 5×2×2 and four repetitions. The factors consisted of application of the five levels of irrigation water salinity: 0.5 (control treatment), 1.5, 3.0, 4.5 and 6.0 dS m-1, in soil without and with bovine biofertilizer (2), tested in the absence and presence (2) of drainage of soil. The variables analyzed were the electrical conductivity of saturated extract, emergency velocity index, plants height, stem diameter, number of leaves, dry weight of shoot, root and total. The 30-day-old plants were irrigated daily with saline waters (treatments) in volumes sufficient to maintain the soil with water content at level of field capacity. Neem seedlings were negatively affected by increased salinity of irrigation water. Since the growth is affected from the electrical conductivity of 0.5 dS m-1; therefore, we conclude that the species is considered to be sensitive to salinity. The results showed that application of bovine biofertilizer and soil drainage are agricultural practices that can minimize the effects of the salts the neem seedlings but does not eliminate it.


Pages 1950-1956 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1324
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Correlations and path coefficient analysis for energy biomass production components in elephant grass (Pennisetum purpureum Schum.)

Avelino S. Rocha, Rogério F. Daher, Camila Q.S.S. de Sant’Anna*, Erina Vitório Rodrigues, Ana Késia F. Vidal, Flávio D. Tardin, Wanessa Francesconi Stida, Rafael S. Freitas, Eduardo P. Furlani, Lília M. Gravina

Universidade Estadual do Norte Fluminense Darcy Ribeiro, Av. Alberto Lamego, n°2000, Parque California, CEP 28035-200, Campos dos Goytacazes, RJ/Brasil
Universidade Federal de Viçosa, Avenida Peter Henry Rolfs, s/n - Campus Universitário, Viçosa - MG, 36570-900.
Embrapa Milho e Sorgo, Rod. MG 424 Km 45, Zona Rural, CEP 35701-970, Sete Lagoas, MG/Brasil
Universidade Federal de Juiz de Fora, Rua José Lourenço Kelmer, S/n - Martelos, Juiz de Fora - MG, 36100-040/Brasil


Abstract
Elephant-grass (Pennisetum purpureum Schum) is known to have a great potential for biomass production, but studies on genotype responses to different sites and growing seasons are still scarce and necessary. This study aimed to estimate correlation and path coefficient analysis for biomass production trait in elephant grass under semi-annual cutting cycles. The experiment was conducted from 2012 to 2015 in a randomized block design with two replications. Seventy-three elephant grass cultivars (genotypes) were assessed during six cutting cycles. Cuts were manually performed when grasses reached a height of 1.5 m (semi-annually). The following variables were analyzed HGT, SD, NT, LW, %DM and DMP. Data were subjected to individual and joint variance analysis, in addition to analysis of genotypic, environmental, and phenotypic correlation and path analysis decomposition. Both genotypes and cuts had significant effects on all the variables. HGT, SD, and LW were significant, positive, and genotypically correlated with DMP. In terms of direct effects on DMP, NT (1.44) stood out with the highest effect and total correlation, thus showing a major contribution to DMP increases. Regarding indirect effects, %DM had a positive influence on DMP via NT and LW. The selection of plants with a high %DM included genotypes with lower SD, HGT, and LW and higher NT. The environmental component had a greater influence on the relationships involving both NT and SD.

Pages 1957-1961 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1325
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Nitric oxide (NO) enhances the adaptive responses of lupine plants against heavy-metal stress

Hanan A. Hashem*, Amira A. Hassanein, Nihal Y. Esmail

Department of Botany, Faculty of Science, Ain Shams University, Abbassia, Cairo, Egypt
National Institution of Occupational Safety and Health, Heliopolis, Cairo, Egypt


Abstract
The present work investigates the possible protective role of nitric oxide (NO) against heavy metals stress in Lupinus termis L. plants. A greenhouse experiment was conducted as a 2 x 2 factorial design with five replications. Lupine seedlings were treated with two concentrations (0.4 mM and 0.6 mM) of sodium nitroprusside (SNP as an NO donor) and subjected to high levels of nickel (Ni) sulfate (100 and 150 mM). The toxic effects of Ni on L. termis plants were evaluated by measuring the oxidative stress markers such as lipid peroxidation, hydrogen peroxide and electrolyte leakage. In addition, growth parameters, endogenous phytohormones, photosynthetic pigment, calcium, magnesium and Ni accumulation in lupin plants grown under Ni toxicity in the presence or absence of NO were also determined. Carbohydrate, organic acid and proline contents were also measured to determine the possible NO-mediated defense strategies in lupine plants to resist Ni stress. The obtained results proved that, Ni toxicity resulted in significantly elevated levels of oxidative stress markers, as well as abscisic acid, jasmonic acid and proline contents, which are associated with significant reduction in growth parameters, photosynthetic pigments, carbohydrate, indole acetic acid and gibberellic acid contents compared with control plants. SNP treatments significantly alleviated the toxic effect of Ni on Lupinus termis L. and increased the amounts of proline, soluble sugars and polysaccharides in shoots and roots, which could be an induced defensive mechanism against heavy-metal stress. Treatment with 0.4 mM SNP was more effective in increasing lupine plants tolerance to Ni toxicity than the 0.6 mM SNP.

Pages 1962-1974 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1379
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Effect of Boron (B) and lime on production of watermelon in dystrophic yellow latosol soil

Raquel Sobral da Silva, Marileia Barros Furtado, Nítalo André Farias Machado*, Hosana Aguiar Freitas de Andrade, Analya Roberta Fernandes Oliveira, Maryzélia Furtado de Farias, Luisa Julieth Parra-Serrano, Jomar do Livramento Barros Furtado, Raissa Rachel Salustriano Silva-Matos, Marcos Renan Lima Leite

Center of Agrarian Sciences and Environmental, Federal University of Maranhão (UFMA), Chapadinha, Brazil
Technological and Exact Sciences Center, State University of Western Paraná (UNIOESTE), Cascavel, Brazil


Abstract
The low concentration of boron in the soil is one of the main challenges for the cultivation of watermelon in regions of the Cerrado biome, due to the appearance of rot apical which may occur due to the lack of boron in the soil or due to boron toxicity by the use of fertilizers without recommendation. There is a narrow range between the appropriate and toxic level pf boron. Therefore, the objective of this study was to evaluate the effect of boron doses on watermelon production in the soils with and without liming. The experiment was carried out in a dystrophic yellow latosol soil, in a randomized block design in subdivide plots: plots (i) liming or without liming and subplots: (ii) boron (0, 2, 4 and 5 kg.ha-1), with 8 treatments and 5 replicates. The data were analyzed by regression analysis. The maximum point of the equation was estimated by equating the first derivative of the equation to zero. The diameter, length, weight, number of commercial fruits, bark thickness, percentage of fruits with apical rot, commercial fruits, female flowers, total soluble solids, productivity and profitability were evaluated. The use of boron provided positive effects on the analyzed variables. However, in concentrations higher than 4 kg ha-1 its behavior was fitted with a quadratic model (R²: 0.77 to 0.99). The range was equivalent to 2 to 4 kg ha-1 of boron with a specific level of 2.4 kg.ha-1, whereas the base saturation raised to 70%, promoted greater productivity for watermelon cultivated in dystrophic yellow latosol under conditions of the closed biome.

Pages 1975-1982 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1405
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Decaying Utricularia-biomass versus soil-based substrate for production of high quality pre-transplanted rice seedlings using floating seedbeds

Fitri Ramadhani, Benyamin Lakitan*, Mery Hasmeda

Graduate School, Universitas Sriwijaya, Palembang 30139, Indonesia
College of Agriculture, Universitas Sriwijaya, Inderalaya 30662, Indonesia
Research Center for Sub-optimal Lands (PUR-PLSO), Universitas Sriwijaya, Palembang 30139, Indonesia


Abstract
Rice growing season at riparian wetlands in Indonesia is started at the end of rainy season before floodwater completely subsides. However, available materials for nursery substrate are limited during flooding period of the wetlands. This study aimed to evaluate three available and affordable substrates for producing high quality rice seedlings. The three substrates evaluated were decaying biomass of Utricularia vulgaris (DBUv); mixed of soil and U. vulgaris biomass plus biochar (SUv+B); and soil amended with biochar (S+B). Rice seedling preparation was done using modified floating seedbeds, adjusted specifically for light weight load of the evaluated substrates. Results of this study indicated that seedlings sown on DBUv substrate were significantly taller than those on S+B or DBUv substrate at 21 DAS. Roots of seedlings sown on DBUv substrate exhibited minimum broken root tips, when they were pulled off the substrate, while more broken root tips were observed in those sown on SUv+B and S+B substrates, causing significantly more shorter intact roots. Broken root tip was closely related to substrate porosity. DBUv substrate had significantly higher porosity than SUv+B and S+B substrates. There were no significant differences in number of leaves and chlorophyll concentration index (CCI) among seedlings grown on all substrates. Better performance of seedlings grown on DBUv substrate was more pronounced on 21-day-old seedlings; therefore, it is recommended to farmers to use DBUv substrate and do transplanting of rice seedlings to paddy field at age of 21-day-old.

Pages 1983-1988 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1406
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Assessment of damage caused by the spider mite Mononychellus planki (McGregor) on soybean cultivars in South America

Jonas Andre Arnemann*, Rubens Alex Fiorin, Jerson Vanderlei Carus Guedes, Henrique Pozebon, Rafael Paz Marques, Clerison Regis Perini, Lindolfo Storck

Departamento de Defesa Fitossanitária, Universidade Federal de Santa Maria, Campus de Camobi, Santa Maria, RS, 97105-900, Brasil
Nufarm Indústria Química e Farmacêutica S.A, Rua Safira, 257, Camobi, Santa Maria, RS, Brasil
Programa de Pós-graduação em Agronomia, Universidade Federal de Santa Maria, Campus de Camobi, Santa Maria, RS, 97105-900, Brasil

Abstract
The aim of this study was to quantify the reduction in grain productivity caused by tetranychid mites in different soybean genotypes. For this purpose, two experiments were carried out in two different experimental sites, one with 20 and another with 25 soybean cultivars. The sites had distinct soil features and were chosen to verify the influence of local conditions in the manifestation of intrinsic soybean plant resistance to spider mites. The experimental design was of randomized blocks with subdivided plots and four replications. The effects of cultivars were assessed in plots 5 x 25 m and yield reduction was investigated in subplots regarding presence and absence of tetranychid mites. The presence of mites on each cultivar was checked weekly after the emergence of soybean plants, until the detection of its occurrence. To evaluate the mite population, 25 leaflets of the upper stratum and 25 of the lower stratum of plants were randomly collected from a 20 cm2 area to quantify the density of mites. The results showed that predominant species was Mononychellus planki (McGregor) (>90%). The other species such as Tetranychus urticae (Koch), Tetranychus ludeni (Zacher), Tetranychus gigas (Pritchard) and Tetranychus desertorum (Banks) were also observed. The population of mites and grain yield loss differed significantly depending on the soybean cultivar. The average reduction in soybean productivity in both experiments was 483 kg of soybean/hectare, corresponding to an average reduction of 20% of the productive potential of the cultivars evaluated. The spider mites can cause a great damage to soybean cultivar. Therefore, growers must regularly scout for its presence in the field, applying control measures as soon as the level of spider mites significantly increases.

Pages 1989-1996 | Full Text PDF| Supplementary Data PDF| doi: 10.21475/ajcs.18.12.12.p1434
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Substrates to produce Jambolan (Syzygium cumini) seedlings

Geany Giovana Silva da Costa, Edilson Costa, Eliana Duarte Cardoso, Flávio Ferreira da Silva Binotti, Alan Mario Zuffo, Marçal Henrique Amici Jorge, Tiago Zoz

Department of Crop Production, State University of Mato Grosso do Sul, 79540-000, Cassilândia, Mato Grosso do Sul, Brazil
Brazilian Agricultural Research Corporation (Embrapa Hortaliças), 70275-970, Distrito Federal, Brasília, Brazil


Abstract
Jambolan (Syzygium cumini L., also known as jambul, java plum, Portuguese plum, among others) is used as an ornamental, medicinal and edible plant and, given its large and diverse uses, high-quality seedlings are desired for fruit farming. This study sought to evaluate the growth and formation of Syzygium cumini seedlings in several substrates. The experiment was conducted in a completely randomized design, with 13 treatments comparing different substrates (S) made with different proportions of bovine manure, subsurface soil, Bioplant®, superfine vermiculite and fine sand. Growth variables of the seedlings, such as height, stem base diameter, mass and biometric ratios were evaluated. Substrates containing 10 to 30% bovine manure and 20 to 40% vermiculite, as in S7 (30%BM+30%SS+10%BP+20%FV+10%FS) and S9 (S9=10%BM+30%SS+10%BP+40%FV+10%FS), yielded the best seedlings with adequate values for diameter, mass and Dickson quality index. Substrates with the largest amounts of bovine manure (50%) showed the worst mass distributions. Substrates with high amounts of Bioplant® or fine sand are not recommended for jambolan seedling formation.

Pages 1997-2003 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1501
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Evaluation of economic efficiency from smallholder cocoa investment in Indonesia: A case study in central Sulawesi province with tropical climate

Effendy*, Made Antara, Rustam Abdul Rauf, Dance Tangkesalu, Christoporus, M. Fardhal Pratama, Muhammad Basir-Cyio, Mahfudz, Zainuddin, Muhardi

Department of Agriculture Economics, Tadulako University, Palu Indonesia 94119, Indonesia
Department of Agroecotechnology, Tadulako University, Palu, Indonesia 94119, Indonesia

Abstract
This research aims to assess the financial feasibility of cocoa investment by smallholders in the province of Central Sulawesi Indonesia. Primary data were collected from 282 cocoa farmers in Sigi and Parigi Moutong Regency. Net Present Value (NPV) and Internal Rate of Return (IRR) were used to evaluate the financial feasibility of cocoa farming with the discount rate of 7% per year. The economic parameters were the price of input and output in 2018. The results showed that the NPV value of IDR 39,906,387 and IRR of 17.82 percent. This implied that smallholding of cocoa is financially feasible to be cultivated but with low profitability. It was due to the less intensive orchards cultivation and old age of cocoa plant. So, more intensive cultivation is required using the young plant and rejuvenation of the old cocoa plants. The government needs to promote cocoa cultivation technology that could improve the productivity of smallholder cocoa and the profitability of farming. So, the smallholding of cocoa in the province of central Sulawesi can become sustainable.

Pages 2004-2010 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1702
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Genetic selection of fig tree (Ficus carica L.) varieties using phenotypic characteristics of rooting and development of softwood cutting

Amauri Cássio Pudente Júnior*, Antonio Flávio Arruda Ferreira, Aparecida Conceição Boliani, Laís Naiara Honorato Monteiro, Bruno Ettore Pavan, Tatiane Paes dos Santos, Maria Gabriela Fontanetti Rodrigues

Luiz de Queiroz College of Agricultre (ESALQ/USP), CEP: 113418-900, Piracicaba, São Paulo, Brazil
Mato Grosso State University (UNEMAT), CEP 78580-000, Alta Floresta, Mato Grosso, Brazil
Faculty of Engineering of Ilha Solteira (FEIS/UNESP), CEP: 15.385-000, Ilha Solteira, São Paulo, Brazil
Faculty of Agronomics Science (FCA/UNESP), CEP: 18610-034, Botucatu, São Paulo, Brazil
Faculty of Agronomics Science and Tecnology (FCA/UNESP), CEP: 17900-000, Dracena, São Paulo, Brazil


Abstract
Although fig tree cultivation has been expanding in Brazil, there is paucity in literature on improvements necessary to propagate it at different environmental conditions. Therefore, this study aimed at assessing quality and genetic potential of thirty fig tree varieties from the germplasm bank for phenotypic analysis of root and softwood cuttings development. The softwood fig cuttings collected from pruning branches of selected varieties. We standardized cuttings of 20 cm in length having straight cut at the basal part and a bevel at the apex. They were placed into the polyethylene box (50 x 17 cm) filled with medium textured expanded vermiculite in a vegetable stove. We used intermittent nebulization irrigation with a flow rate of 0.012 m3s-1 of water in 20 seconds each 3 minutes. After 60 days, cuttings were transplanted into plastic bags (30 x 20 cm) with capacity of 1.2 L filled with 1/3 soil and 2/3 organic compounds, where placed in a greenhouse, protected with 50 % shade black polypropylene mesh, with intermittent irrigation for 15 minutes with a flow rate of 0.243m3s-1 every 4 times a day. After 105 days, evaluations consisted of cuttings survival number, length of the largest root, root fresh and dry matter, shoot number, length of the largest shoot, shoot fresh and dry matter. The results of analyses showed Roxo de Valhinhos, Ilha Solteira, Brunswick, IAC, Genoveso, IAC, varieties 39, 41 and 42 as high performance varieties. In addition, results indicated low genotypic coefficient of variation in relation to environmental coefficient of variation in most characters. Besides, only two characters showed superior heritability; thus, we concluded that there is no genetic variability between varieties for most measured characters. Since the studied population presented low genetic variability using morphological descriptors of roots we recommend unsuccessful selection for tested characters through breeding programs. However, cuttings survival number is of great importance to select fig genotypes.

Pages 2011-2018 | Full Text PDF| doi: 10.21475/ajcs.18.12.12.p1627



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