Australian Journal of Crop Science   AJCS

Effect of morphological trait variance on plant yield in different Trigonella foenum-graecum L. varieties

Annu Sindhu, Suresh Kumar Tehlan, Ashok Chaudhury*

Plant Molecular Biology Laboratory, Department of Bio and Nano Technology, Bio and Nano Technology Centre, Guru Jambheshwar University of Science and Technology, Hisar-125 001, Haryana, India
Present Address: 8/21-29, Trickey Avenue, Sydenham, Victoria, VIC-3037, Australia
Department of Vegetable Sciences, CCS Haryana Agriculture University, Hisar-125004, Haryana, India

Abstract
Trigonella’s rich biochemistry globally signifies it as a medicinal herb. India is the largest producer and exporter of Trigonella seeds. Its products are used on a large scale as raw material preparation of food and are also used in cosmetics and pharmaceutical industry especially for steroid hormones synthesis. Therefore, to meet global production requirements, superior trait varieties are in constant demand. In the present investigation, seeds of ninety T. foenum-graecum L. varieties from and around the most productive Trigonella belt in India were collected. The varieties procured from the States of Gujarat, Rajasthan and Haryana were employed to study nine quantitative and nine qualitative traits. These traits include plant height, pods per plant, seeds per pod, yield per plant, days to 50% flowering, days to maturity, days to field emergence, pod length, branches per plant, plant growth habit, leaf margin, leaf margin pigmentation, leaf tip, number of pods per axis, seed color, seed size, seed luster and plant category. The numerical data obtained was subjected to analysis of variance, genotypic and phenotypic variance, heritability, path coefficient analysis, genetic advance, coefficient of variance and analysis of variance, covariance, multivariate analysis and cluster analysis. Traits profoundly contributing towards yield were traced as growth habit, flowering date, branches, and pods per plant and seeds per pod. Path coefficient analysis revealed that seeds per pod had highest positive impact on yield per plant followed by pods per plant, branches per plant, plant height and days to 50% flowering. Therefore, it is concluded that high heritability estimates would be of great significance for breeding programs to attain superior varieties on the basis of phenotypic performance.

Pages 1-10 | Full Text PDF| Supplementary Data| doi: 1021475/ajcs.18.12.01.pne211
…………………………………………………………………………………………………………………………………………………………………………………..

Fruit production and SPAD index of pepper (Capsicum annuum L.) under nitrogen fertilizer doses

Flávio da Silva Costa, Antônio Suassuna de Lima, Ivomberg Dourado Magalhães, Lucia Helena Garófalo Chaves, Hugo Orlando Carvallo Guerra

Field Education Department, Federal University of Amapá, Av. Intendente Alfredo Pinto, SN, Mazagão, Amapá, Brazil
Technology Center and Natural Resources, Federal University of Campina Grande, Av. Aprigio Veloso, 882, Campina Grande, Paraíba, Brazil
Agricultural Science Center, Federal University of Alagoas, BR-104, km 85, Rio Largo, Alagoas, Brazil

Abstract
The availability of nitrogen (N) in the soil influences the vegetative development of plants. However, the requirement is usually different between crops. The objective of the present work was to determine the fruit production and the SPAD index of pepper submitted to different amounts of nitrogen applied to the soil and applying this index in the production prognostic of the crop. The experiment was carried out under greenhouse conditions, Paraíba State, Brazil. The treatments were carried out in a completely randomized design, in a 3 × 5 factorial experiment, i.e., All Big, Yolo Wonder and Vermelho Samurai-Sais cultivars and five nitrogen fertilization doses (0, 33.33, 66.67, 100 and 133.33 mg kg-1 soil) with three replicates. At the time of flowering and harvesting of the peppers, the SPAD index was determined, using chlorophyll meter. The total production of fruits per plant was obtained weighing the fruits. Pepper production of all cultivars increased with nitrogen application at 120 days after sowing, using different soil nitrogen applications to reach their maximum productions. The Yolo Wonder cultivar had the maximum production (483.7 g of fruit/plant). The plants that presented SPAD index of 58.5 in the flowering stage showed the maximum fruit yield. The quantification of the SPAD index at the reproductive stages can be used in the prognosis of pepper production.

Pages 11-15 | Full Text PDF| doi: 10.21475/ajcs.18.12.01.pne453
…………………………………………………………………………………………………………………………………………………………………………………..

Application of nitrogen fertilizer in high-demand stages of soybean and its effects on yield performance

Giovane Moreno*, Alfredo Junior Paiola Albrecht, Leandro Paiola Albrecht, Clovis Pierozan Junior, Laercio Augusto Pivetta, Augusto Tessele, Juliano Bortoluzzi Lorenzetti, Ruan Carlos Navarro Furtado

Federal University of Paraná - Campus Palotina. Address: Rua Pioneiro, 2153, Jardim Dallas CEP: 85950-000 Palotina – PR, Brazil
Federal University of Paraná - Campus Palotina, Department of Agronomy Address: RuaPioneiro, 2153, Jardim Dallas CEP: 85950-000 Palotina – PR, Brazil
Federal Institute of Education Science and Technology of Paraná – Campus Palmas. Department of Agronomy. Address: Av. Bento Munhoz da Rocha Neto s/nº - Palmas – PR, Brazil

Abstract
The typical nitrogen supply recommendation for soybeans is the application of inoculant with no additional required supplementation via fertilization. However, the adoption of no-till farming, the release of high-yielding cultivars and recent studies concerning soybean response to late application of nitrogen have sparked doubts about the possible benefits of nitrogen fertilization. Recent studies using nitrogen fertilization of soybeans show no increase in yield, due to efficient biological fixation (BNF); however, the effects of different application times have not been widely studied. In this context, the aim of this study was to investigate different methods and times of nitrogen fertilization of soybeans. Using the recommended supplements, along with a search of the scientific literature on the same theme, nine treatments were evaluated. These consisted of the application of single and split doses of nitrogen, at 20 kg.ha-1 and 40 kg.ha-1, during sowing and reproductive stage R4. The nitrogen source used was urea (45% nitrogen). It was applied in adequate environmental conditions, at levels typically found in rain forecasts, and were incorporated into the soil to avoid losses by volatilization. The split application of nitrogen (at sowing + stage R4) provided an increase in yield, reaching a 47% difference in treatment 6 in relation to control, not taking into account supplementation costs. Furthermore, the variables related to plant architecture displayed no significant differences.

Pages 16-21 | Full Text PDF| doi: 10.21475/ajcs.18.12.01.pne507
…………………………………………………………………………………………………………………………………………………………………………………..

Phenotypic characterization of elite quality protein maize (QPM) inbred lines adapted to tropical-highlands and the association studies using SSR markers

Demissew Ababulgu*, Hussein Shimelis, Mark Laing, Amelework Beyene

African Center for Crop Improvement, University of KwaZulu-Natal, Private Bag X01, Scottsville 3209, Pietermaritzburg, South Africa
Ethiopian Institute of Agricultural Research, Plant Protection Research Center, P.O. Box 37, West Shoa, Ambo, Ethiopia

Abstract
A well-characterized germplasm is a requisite to develop productive and better adapted crop cultivars. Morphological and molecular markers and pedigree analyses are widely used in germplasm characterization, and to establish genetic diversity and relationship in maize. The objectives of this study were to characterise newly developed quality protein maize (QPM) inbred lines adapted to tropical-highlands using phenotypic traits and to determine the association with simple sequence repeat (SSR) markers. Thirty-six maize inbred lines (30 QPM and six non-QPM) adapted to tropical-highlands of Ethiopia were evaluated using 18 phenotypic traits and 26 selected SSR markers. Significant phenotypic variations were observed among inbred lines for all measured traits. Grain yield showed moderate and high genotypic and phenotypic coefficients of variation, respectively. Ear height and thousand kernel weight had high heritability (≥ 0.70) which could be a source of high genetic advance through selection. Principal component and cluster analysis using unweighted paired group method using arithmetic averages (UPGMA) revealed the presence of two to four distinct genetic groups, while population structure analysis based on phenotypic data showed the presence of four to six genetic groups. Seven QPM inbred lines (KIT32Q, 142-1eQ, SRSYN20Q, FS67(BC2), FS170Q, FS60, and F7215) with complementary phenotypic traits and relatively better yield performance were selected using the phenotypic traits and SSR based genotyping for cultivar development and/or conservation.

Pages 22-31 | Full Text PDF| Supplementary Data| doi: 10.21475/ajcs.18.12.01.pne567
…………………………………………………………………………………………………………………………………………………………………………………..

Improving the prediction of potato productivity: APSIM-Potato model parameterization and evaluation in Tasmania, Australia

Dinah Borus*, David Parsons, Mark Boersma, Hamish Brown, Caroline Mohammed

Tasmanian Institute of Agriculture/School of Land and Food, University of Tasmania, Australia
Department of Agricultural Research for Northern Sweden, Swedish University of Agricultural Sciences, Umeå, Sweden
The New Zealand Institute of Plant and Food Research, Lincoln, New Zealand

Abstract
Crop growth models are required to be extensively evaluated against actual data from field grown plants in order to have confidence in their prediction of crop productivity under various management options or a future changed climate. We evaluated the ability of the APSIM-potato model to predict production, phenology, and N-uptake of potato (Solanum tuberosum L.) under Tasmanian conditions. On-farm monitoring plots were established in north-west Tasmania within four different well–managed potato fields grown during the 2012/13 cropping season. Detailed soil and crop data sets measured in the on-farm plots planted with two potato cultivars, ‘Russet Burbank’ and ‘Moonlight’ were used to parameterise and evaluate the model. The model realistically reproduced the observed tuber yield with high precision (a mean N-RMSE of 15.4% and modelling efficiency of 1.0 for both cultivars). Measured mean tuber yield was 17 t ha-1 for ‘Russet Burbank’ with a simulated yield of 20 t ha-1. For ‘Moonlight’ simulated tuber yield was 16.0 t ha-1 compared to measured yield of 15.1 t ha-1. The simulation results provide insight on the model performance under Tasmanian conditions. The results suggest that the model has potential to be used for purposes such as simulating productivity under various management options and climate change impact studies. Additional experiments are however required to improve cultivar specific input parameters such as phenology, leaf area and leaf duration and other functions that needs further refinement to improve model ability to simulate plant organs beside the tuber.

Pages 32-43 | Full Text PDF| doi: 10.21475/ajcs.18.12.01.pne570
…………………………………………………………………………………………………………………………………………………………………………………..

Nitrogen and potassium fertilization on the development and chlorophyll index of irrigated wheat in the Cerrado, Central Brazil

Danityelle Chaves de Freitas, Edna Maria Bonfim-Silva*, Tonny José Araújo da Silva, Helon Hébano de Freitas Sousa, Marcio Koetz, Alessana Franciele Schlichting, Salomão Lima Guimarães

Federal University of Mato Grosso, Institute of Agricultural and Technological Sciences, 5055 Estudantes Ave. Rondonópolis, 78.735-901, Brazil

Abstract
As new wheat cultivars (Triticum aestivum L.) continue to be developed, they enable cultivation in regions experiencing tropical types of climate under conditions of irrigation. However, further studies are necessary to provide details regarding the properties of the nutrients and their behavior under these conditions to advance the plant growth. Therefore, this study aimed at assessing the development of the irrigated wheat in Oxisol, using combined doses of nitrogen and potassium. These fertilizers are added in the tropical areas as a viable alternative to expand the wheat cultivable regions. Adopting the completely randomized block design, the experiment was conducted for two consecutive years in the State of Mato Grosso, Brazil. Five nitrogen doses (0, 70, 140, 210, 280 kg ha-1), using urea as the fertilizer, and five potassium doses (0, 50, 100, 150 and 200 kg ha-1), using Simple superphosphate as the fertilizer were employed with four replicates. Using the conventional spraying irrigation method, the plant height, number of leaves and tillers, plant lodging and chlorophyll index were assessed. The nitrogen and potassium doses were observed to influence the irrigated BRS 254 wheat in terms of the growth and chlorophyll levels. Potassium expressed the best results for the variables of this study when added alone. The addition of nitrogen demonstrated remarkable results during the second agricultural year.

Pages 44-50 | Full Text PDF| doi: 10.21475/ajcs.18.12.01.pne623
…………………………………………………………………………………………………………………………………………………………………………………..

Effect of different plant beds and fertilizers on Stevia (Stevia rebaudiana Bertoni) production

Robabeh Asghari

Plant Production Department, Imam Khomeini Higher Education Centre, Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran

Abstract
Stevia rebaudiana Bertoni is well-known for its high content of steviol glycoside, a diterpene compound (about 4–20%) in dryleaf matter that is responsible for providing the non-caloric value sweet taste. Steviol glycosides are natural sugar substitutes for diabetics and other people on carbohydrate-controlled diets. Studies revealed that the glycosides yield, especially stevioside, greatly depends on the total biomass yield, which in turn depends on agricultural practices for cultivation of stevia. In this study, the effect of five various combinations of soil, cocopeat, perlite, and vermicompost plant beds mixed with four different fertilizers of tea compost, vermiwash, Hoagland and water, on four different physiological (leaf area, stem length, fresh weight and dry weight) and six different biochemical (chlorophyll content, carotenoid, protein, glucose, phenols and rebaudiosides) characteristics of plant were evaluated. To gain the highest content of biochemical compounds, especially all types of rebaudiosides, a combination of vermicompost, perlite and cocopeat with vermiwash or any other fertilizers can be useful.

Pages 51-55 | Full Text PDF| doi: 10.21475/ajcs.18.12.01.pne643
………………………………………………………………………………………………………………………………………………………………………..

Physicochemical characterization of chitosan and its effects on early growth, cell cycle and root anatomy of transgenic and non-transgenic maize hybrids

Mayron Martins, Valdir Veroneze-Júnior, Marília Carvalho, Diogo T. Carvalho, Sandro Barbosa, Antônio C. Doriguetto, Paulo C. Magalhães, Cleberson Ribeiro, Marcelo H. dos Santos, Thiago C. de Souza*

Federal University of Alfenas, Institute of Nature Sciences, Street Gabriel Monteiro da Silva, 700, CEP 37130-000, Alfenas-MG, Brazil
Federal University of Alfenas, Faculty of Pharmaceutical Sciences, Street Gabriel Monteiro da Silva, 700, CEP 37130-000, Alfenas-MG, Brazil
Federal University of Alfenas, Chemical Institute, Street Gabriel Monteiro da Silva, 700, CEP 37130-000, Alfenas-MG, Brazil
National Maize and Sorghum Research Center (Embrapa), BOX 151, CEP 35701-970, Sete Lagoas-MG, Brazil
Federal University of Viçosa, Departament of Chemistry, Street Peter Henry Rolfs, s/n, CEP 36570-000, Viçosa,-MG, Brazil
Federal University of Viçosa, Department of Biology, Street Peter Henry Rolfs, s/n, CEP 36570-000, Viçosa,-MG, Brazil

Abstract
The objectives of this study were to perform the physicochemical characterization of chitosan, to evaluate its effects on germination, early growth, root anatomy and on the cell cycle of two maize hybrids. The hybrids DKB 390 and DKB 390 VTPRO (transgenic) were used. DKB390 VTPRO is from Monsanto, and the event number is 89034, which expresses the proteins Cry1A105 and Cry2AB2. For the physico-chemical characterization of chitosan, the following analyzes were performed:, elemental analysis, total ash, infrared absorption spectroscopy, nuclear magnetic resonance, powder X-ray diffraction, thermogravimetric analysis, scanning electron microscopy and viscosity. With the analysis of infrared absorption spectroscopy, nuclear magnetic resonance, powder X-ray diffraction, thermogravimetric and elemental analysis it was observed that the structure of chitosan presents a low level of deacetylation. Chitosan had a total ash value of 1.32% and high viscosity. By scanning electron microscopy the chitosan was classified as porous and fibrous structure. Increase in the seed germination rate was observed in both maize hybrids in the presence of chitosan, without changes in the initial growth. The cell analyzes showed that the chitosan was not toxic even at high concentrations, since the mitotic index remained unchanged and no chromosomal abnormalities were detected. The effects of chitosan in root anatomy were evaluated through the measurements of sections of root tips on histological preparations, and the genetically modified hybrid presented the best results. As conclusion, the use of chitosan in appropriate concentrations may favor the development of maize (especially transgenic) acting on germination or changing the root anatomy and consequently increasing resistance and adaptation of the seedlings to adverse conditions.

Pages 56-66 | Full Text PDF| Supplementary Data|doi: 10.21475/ajcs.18.12.01.pne649
…………………………………………………………………………………………………………………………………………………………………………………..

Multivariate analysis used as a tool to select snap bean (Phaseolus vulgaris L.) genotypes

Tâmara Rebecca Albuquerque de Oliveira*, Geraldo de Amaral Gravina, Gustavo Hugo Ferreira de Oliveira, Lanusse Cordeiro de Araujo, Kleberson Cordeiro Araújo, Derivaldo Pureza da Cruz, Antônio Teixeira do Amaral Junior, Marcelo Vivas, Rogério Figueiredo Daher 

Center for Agro-Food Science and Technology, State University of Northern Fluminense, Rio de Janeiro, RJ, 28035-200, Brazil
Federal University of Sergipe, Glória, SE, 49100-000, Brazil
Federal Fluminense Institute, Bom Jesus de Itabapoana, RJ, 28060-010, Brazil

Abstract
Abstract - Snap bean is a popular and promising vegetable in Southeastern Brazil . The aim of the current study is to use the multivariate analysis as tool to select snap bean genotypes presenting desired agronomic traits. The study followed a randomized block experimental design, with 4 repetitions and 30 genotypes. The principal component and biplot analyses, as well as clustering, were conducted according to the UPGMA method in order to investigate the mean pod weight (MPW), number of seeds per pod (NSP), pod length (PL), pod width (PWi), total pods (TP), weight of one hundred seeds (W100S), pod yield (PY) and grain yield (GY). The PL, NSP, MPW and W100S presented positive correlation with GY, besides their indication to direct genotype selection. The PWi and TP were efficient for PY selection. The multivariate analyses suggested the selection of lines UENF 7-10-1, UENF 7-12-1 and UENF 7-20-1, which presented good seed yield, as well as of UENF 14-22-3 and UENF 14-23-3, which showed aptitude to production. Lines located in Group II (UENF 14-4-3, UENF 15-6-4, UENF 7-4-1, UENF 7-9-1, UENF 7-7-1, UENF 7-5-1) did not have good performance in the measured traits and could be discarded. Line UENF 1445 “PARENT 19” proved its potential for seed yield, thus it was promising for the development of productive genotypes. Line 14-3-3 presented good aptitude for negatively correlated variables, because it associated good trait with morphology, seed yield, and pod and grain yield morphological traits.

Pages 67-73 | Full Text PDF| doi: 10.21475/ajcs.18.12.01.pne661
…………………………………………………………………………………………………………………………………………………………………………………..

Phytomass of lettuce cultivars under water replenishment levels

Silvanete S. da Silva*, José Dantas Neto, Carlos Alberto Vieira de Azevedo, Juarez Paz Pedroza, Roberto Vieira Pordeus, Claudia Facini dos Reis

Federal University of Campina Grande, Academic Unit of Agricultural, Engineering, Campina Grande, CEP 58.109-970, Paraíba, Brazil

Abstract
Water scarcity in the semi-arid region causes significant losses in the socioeconomic activities, with reduction in agriculture. Therefore, this study aimed to evaluate the effect of the application of irrigation depths on the phytomass accumulation of lettuce cultivars. The experiment was carried out at the Academic Unit of Agricultural Engineering, in 10 beds composed of 78 plants each, at spacing of 0.25 × 0.30 m. The treatments were set in a 5 x 3 factorial scheme, with five water replacement levels, The irrigation depths were applied based on the reference evapotranspiration – ETo, as follows: 70% (L1), 80% (L2), 90% (L3), 100% (L4) and 115% (L5) of the reference evapotranspiration – ETo, and three cultivars: Elba’ – C1, ‘Iceberg’ – C2 and ‘Looseleaf’ – C3, four replicates. Irrigations were applied through a drip system with the aid of the program ETo calculator-FAO Penman-Monteith to estimate the reference evapotranspiration. The following variables were determined: fresh matter (FM), dry matter (DM), root fresh matter (RFM), root dry matter (RDM), number of leaves (NL) and plant height (PH). According to the results, the increment in irrigation depths increased leaf fresh matter, number of leaves, plant height and root dry matter. The irrigation depth of 192.4 mm cycle-1, i.e., 100% of evapotranspiration under field conditions led to greater yield.

Pages 74-80 | Full Text PDF| doi: 10.21475/ajcs.18.12.01.pne669
…………………………………………………………………………………………………………………………………………………………………………………..

Quality of strawberry seedlings can determine precocity

Rosiani Castoldi da Costa*, Eunice Oliveira Calvete, Fabiola Stockmans DeNardi, Ana Cláudia Pedersen, José Luís Trevizan Chiomento, Nicolas dos Santos Trentin

University of Passo Fundo, Faculty of Agronomy and Veterinary Medicine, Campus I-Barrio San José - BR 285 - Km 171, CEP :99052-900, 611 Pillar Box - Passo Fundo, Rio Grande do Sul, Brazil 

Abstract
The development of day-neutral (DN) strawberry cultivars and their relationship with the quality of strawberry seedlings are important for the identification of precocity, ie. early flowering and fruiting. This study aimed to test whether the variability between morphoagronomic DN strawberry cultivars is associated with precocity. The treatments were four cultivars of strawberry (Albion, Aromas, Portola and San Andreas), and three plant crown diameters (ØB ˂ 8 mm, ØA between 8.1 and 12 mm and ØA+ ˃ 12 mm). The design was completely randomized with five replications under split plot scheme. The plants were grown in plastic containers filled with commercial substrate. The analyzed variables were the phenological stages, thermal sum accumulated (TSa) and phyllochron. The phenological data were submitted to multivariate analysis. The phyllochron (°C day leaf-1) was estimated as the inverse angular coefficient of linear regression. Aromas ØB and Portola ØA were the most divergent. Aromas and San Andreas ØA+ were earlier maturity with phyllochron of 89.28 and 85.47ºC, respectively. Phenological stage 71 demonstrated larger relative contribution for separation of the groups according to the crown diameter. The quality of seedlings for DN cultivars is determined by the crown diameter (˃8.1 mm).

Pages 81-86 | Full Text PDF| doi: 10.21475/ajcs.18.12.01.pne710
…………………………………………………………………………………………………………………………………………………………………………………..

Cherry tomato production on different organic substrates under protected environment conditions

Edilson Costa, Flávio Ferreira da Silva Binotti, Eliana Duarte Cardoso, David Barbosa Lima Júnior, Tiago Zoz and Alan Mario Zuffo*

Department of Crop Production, State University of Mato Grosso do Sul, 79540-000, Cassilândia, Mato Grosso do Sul, Brazil

Abstract
The cherry tomato (Lycopersicon esculentum var. cerasiforme) is gaining importance as an alternative crop, mainly for small farms that use family hand labor and organic management. In this study, we investigated the effects of organic substrate combinations of cattle manure (M), vermicompost (VC), and vermiculite (V) on the yield and quality of cherry tomato fruits. Cherry tomato plants of the cultivar Carolina were grown under greenhouse conditions in 5-L pots. The five investigated substrate combinations were as follows: (T1) 80% M + 10% VC + 10% V; (T2) 70% M + 15% VC + 15% V; (T3) 60% M + 20% VC + 20% V; (T4) 50% M + 25% VC + 25% V; and (T5) 40% M + 30% VC + 30% V. Plant growth, tomato yield, and physicochemical properties of the fruits were measured. The results showed that combinations of 50% M + 25% VC + 25% V and 40% M + 30% VC + 30% V led to the best growth and adaptation of cherry tomato plants, resulting in larger and more rounded fruits. The substrate containing 40% M + 30% VC + 30% V resulted in higher numbers of fruits per plant. Different substrate combinations did not affect the chemical quality of the fruit. Therefore, our study has provided valuable information on the use of organic substrates in cherry tomato production under protected environment conditions. Based on our results, the different combinations of cattle manure, vermicompost, and vermiculite used in this study represent excellent options for reducing production costs and re-using organic byproducts.

Pages 87-92 | Full Text PDF| doi: 10.21475/ajcs.18.12.01.pne749
…………………………………………………………………………………………………………………………………………………………………………………..

Effects of seed size and sowing depth in the emergence and morphophysiological development of soybean cultivated in sandy texture soil

Arnaldo Cintra Limede, Carlos Eduardo da Silva Oliveira, André Zoz, Alan Mario Zuffo*, Fábio Steiner, Tiago Zoz

Department of Crop Production, State University of Mato Grosso do Sul, 79540-000, Cassilândia, Mato Grosso do Sul, Brazil

Abstract
Seed size and sowing depth are important factors for an adequate plant stand in soybean crops. This study aimed at assessing the emergence and morphological development of soybean plants, affected by seed size and sowing depth in sandy texture soil. The trial was carried out in a greenhouse with an experimental design of randomized blocks, organized in the factorial scheme 3 x 3. The factors were seed size (sieves 6.0, 6.5, and 7.0 mm) and sowing depth (2.0, 4.0, and 6.0 cm) with four replications. We assessed the emergence, emergence speed index, mean time of emergence, number of leaves per plant, stem diameter, plant height, dry mass of leaves, dry mass of stem, dry mass of root system, dry mass of shoot, total dry mass of plant, leaf area, root system volume, root system density, shoot/root ratio, ratio of leaf area, and ratio of leaf dry mass. The seed size does not influence the emergence of soybean seedlings; however, the seeds of sieve 7.0 mm produce plants with a higher dry mass of stem, dry mass of shoot, and root system volume. The soybean sowing at 4.0 cm depth resulted in the highest morphological development.

Pages 93-98 | Full Text PDF| doi: 10.21475/ajcs.18.12.01.pne765
…………………………………………………………………………………………………………………………………………………………………………………..

Ethrel® stimulant increases the activity of soluble invertase isoforms in rubber tree (Hevea brasiliensis) bark tissues

Débora Domiciano*, Pollyanna Aparecida Carvalho, Luiz Edson Mota de Oliveira, Hilda Beatriz W. Cárdenaz, Débora de Oliveira Prudente

Setor de Fisiologia Vegetal, Departamento de Biologia, Universidade Federal de Lavras, Lavras, MG 37200-000, Brazil EEPF "Indio Hatuey", Universidad de Matanzas "Camilo Cienguegos", Cuba

Abstract
Ethrel® is a commercial stimulant based on ethylene commonly used in exploitation systems for increases sucrose hydrolysis and improve dry rubber production by rubber tree (Hevea brasiliensis). The main enzymes that act on sucrose hydrolysis and provide hexoses for rubber biosynthesis are invertase isoforms: Vacuolar Invertase (VIN), Cell Wall Invertase, (CWIN) and Neutral Invertase (NIN). The aim of this study was to evaluate the contribution of each of the invertase isoforms (VIN, NIN and CWIN) in rubber tree bark tissues stimulated with Ethrel® and its relationship with the rubber production. For this, they were made two Ethrel® applications in commercial planting of RRIM 600 clone rubber trees, a 34-day interval. Ethrel® stimulated rubber trees showed a 40% increase in dry rubber production. This work demonstrated that this increase is due to the higher performance of the NIN and VIN invertase isoforms, which contributed to the availability of hexoses in the intracellular compartment favoring rubber biosynthesis and improving the inflow of water necessary to the latex flow.

Pages 99-107 | Full Text PDF| doi: 10.21475/ajcs.18.12.01.pne770
…………………………………………………………………………………………………………………………………………………………………………………..

Biometric characterization and seed germination of giant mimosa [Mimosa bimucronata (DC) O. Kuntze]

Luan Danilo Ferreira de Andrade Melo*, João Luciano de Andrade Melo Junior, Vilma Marques Ferreira, João Correia de Araújo Neto, Maria Inajal Rodrigues da Silva das Neves

Center of Agricultural Sciences, Federal University of Alagoas, Rio Largo, Alagoas, Brazil

Abstract
This study aimed to characterize the biometric characteristics of Mimosa bimucronata (DC.) O. Kuntze seeds and to elucidate their physiological characteristics with respect to the effect of treatments and temperature on dormancy breaking. Treatments consisted of control (intact seeds), chemical scarification using sulfuric acid (density: 1.84 and purity: 98%) for 5 min, integument cutting at the region opposite the micropyle, soaking at 80°C followed by cooling for 24 h, and soaking in water at an ambient temperature for 24 h and 48 h. Subsequently, the effect of different temperatures (constant at 5°C, 10°C, 15°C, 20°C, 25°C, 30°C, 35°C, and 40°C and an alternating temperature of 20°C–30°C) on seed germination was assessed. The average dimensions of seeds with an initial moisture content of 16.25% were as follows: length: 4.17 mm, width: 2.95 mm, and thickness: 0.69 mm. Optimum seed germination and seedling development in M. bimucronata were obtained by seed integument cutting at 30°C.

Pages 108-115 | Full Text PDF| doi: 10.21475/ajcs.18.12.01.pne773
…………………………………………………………………………………………………………………………………………………………………………………..

Effect of nitrogen source and oxygen deficiency on carbon metabolism and antioxidant system of rubber tree plants (Hevea spp.)

Pollyanna Aparecida de Carvalho, Luiz Edson Mota de Oliveira, Débora Domiciano, Jullyanna Nair de Carvalho, Débora de Oliveira Prudente, Rubens José Guimarães

Fisiologia Vegetal, Departamento de Biologia, Universidade Federal de Lavras, Lavras, Minas Gerais, Brasil
Universidade Federal do Vale do São Francisco, Petrolina, Pernambuco, Brasil
Departamento de Agricultura, Universidade Federal de Lavras, Lavras, Minas Gerais, Brasil

Abstract
Oxygen deficiency in roots affects key functions such as nutrient and water uptake; furthermore, liquid-CO2 assimilation, stomatal conductance/ transpiration and carbohydrate translocation are also affected. Under oxygen depletion, there is also an uncontrolled increase of free radicals in cells. The nitrogen application has been observed to increase the plant tolerance to oxygen deficiency. Indeed, NO3− and NH4+ (nitrogen forms) may induce distinct metabolic responses under hypoxia. Nevertheless, the beneficial effects of N during hypoxia it is not fully explained. In this study, the nitrogen (N) role in the physiology and metabolism of rubber plants (Hevea brasiliensis) subjected to oxygen deficiency was evaluated. The experiment was conducted with plants supplied with KNO3 (8 mM N) or (NH4)2SO4 (8 mM N) in nutrient solution for 3 days. The experiments were arranged in a completely randomized design (CRD) in a factorial arrangement (2x2x4). The experiment had four treatments and four time points (12, 24, 48 and 72 hours) for stress measurements with four replicates, totaling 64 plants. Data were analyzed using analysis of variance (ANOVA), and the means were compared using the Scott-Knott test (p ≤ 0.05). Gas exchange measurements and biochemical analyzes were performed at 12, 24, 48 and 72 hours after treatment induction. The results showed that, net photosynthesis, stomatal conductance and transpiration rate in stressed plants decreased significantly when compared to the control plants, regardless of nitrogen source. However, under hypoxia, plants treated with NO3- showed significantly higher CO2 assimilation, overcoming the treatment with NH4+. Therefore, when comparing plants treated with NO3- and those treated with NH4+ under flooding conditions (for 3 days), the first presented higher sucrose production, consequently higher invertase isoform activity. Under hypoxia, NO3- treated plants also showed higher antioxidant system efficiency. Therefore, H2O2 content was higher in plants treated with NH4+. Thus, we concluded that carbon metabolism such as carbohydrate anabolism, catabolism and transport were negatively affected by hypoxia. However, NO3- addition in contrast to NH4+ treatment reduced damage caused by oxygen deficiency increasing the level of tolerance of the plant to stress.

Pages 116-125 | Full Text PDF| doi: 10.21475/ajcs.18.12.01.pne774
…………………………………………………………………………………………………………………………………………………………………………………..

Genetic variability for yield and yield components of Thai chilli (Capsicum spp.) landraces under inorganic and organic agricultural systems

Sorapong Benchasri* and Panumas Pruthikanee

Department of Plant Science, Faculty of Technology and Community Development, Thaksin University, Pa Phayom, Phatthalung Thailand P.O. 93210

Abstract
Yield components and genetic variation for high yield potential is an essential prerequisite for the development of chilli cultivars with improved production system. The objectives of this study were to evaluate yield and yield component and genotypic variability of chill germplasm. Each experiment was conducted in a Randomized complete block design (RCBD) with four replications of two production systems between December 2012 and June 2013. The results showed that in this germplasm, there were highly significant variability (p≤0.01) for fruit width, fruit length, number of fruits plant-1, fruit weights fruit-1 and fruit yields plant-1. The highest number of quality fruit was found on Chee genotype 519.42±14.27 and 512.69±12.35 fruits plant-1 under inorganic and organic agricultural systems, respectively. The lowest number of quality fruit was observed on Labmeunang genotype (27.63±6.10 and 19.89±5.78 fruits plant-1 under the inorganic agricultural system and organic agricultural system, respectively). Chee genotype produced the highest yield under the inorganic and organic agricultural system 701.22±18.58 and 630.61±16.35 g plant-1, respectively. Labmeunang genotype produced the lowest yield (26.45±10.05 g.plant-1) under the organic agricultural system. The results indicated that Chee genotype show potential for chilli production in both systems.

Pages 126-134 | Full Text PDF| doi: 10.21475/ajcs.18.12.01.pne778
…………………………………………………………………………………………………………………………………………………………………………………..

Agro-morphological characterization of diverse sorghum lines for pre-and post-flowering drought tolerance

Yves Emendack*, John Burke, Jacob Sanchez, Haydee Echevarria Laza, Chad Hayes

Plant Stress and Germplasm Development Unit, Cropping Systems Research Laboratory, USDA-ARS, 3810, 4th Street, Lubbock, Texas, U.S.A.
Department of Soil and Crop Sciences, Texas Tech University, Lubbock, Texas, U.S.A.

Abstract
The impact of drought stress on sorghum yield does not only depend on the intensity and timing of drought, but as well on the developmental stage of the crop. One of the limitations in breeding for pre-and/or postflowering drought stress resistance in sorghum is the less availability of diverse genetic sources possessing drought tolerant agro-morphological or physiological traits that could be introgressed into elite sorghum lines. This research evaluate a diverse group of 54 introgressed, converted, and commonly used sorghum breeding lines for their tolerance to field drought stress imposed at the pre-flowering and post-anthesis developmental stages in 2015 and 2016 growing seasons. Agro-morphological characteristics such as panicle area, panicle width, and percent green leaf and yield-related characteristics such as total above ground dry biomass and dry panicle weight were identified as significant predictors of grain yield under water stress. The current research identifies other sources that could be use by breeding programs as donor lines for traits related to pre-and postflowering drought tolerance in sorghum. Following statistical distribution and Tukey-Krammer HSD connecting letter tests, lines JB39, SC191, and SC270 and RIL R.11269 were identified as plausible sources for pre-flowering drought tolerance, and JB14, JB15, JB19, JB22, JB24, JB25, JB26, and JB33 as sources for the staygreen trait. While the staygreen is a good selection tool for postflowering drought tolerance, identifying staygreen lines with minimal reductions in grain yield and with earlier flowering dates (JB14, JB22, JB24 and JB25 in this study) than most commonly used staygreen donor lines, will ensure that grain yield is not over sacrificed by the ability of the crop to staygreen under terminal drought conditions.

Pages 135-150 | Full Text PDF| Supplementary Data| doi: 10.21475/ajcs.18.12.01.pne790
…………………………………………………………………………………………………………………………………………………………………………………..

Agronomic performance of jambu (Acmella oleracea) using organic fertilization

Gilberta Carneiro Souto, Leilson Costa Grangeiro*, Sergio Antônio Lopes de Gusmão, Valdivia de Fátima Lima de Sousa, Antônio Elson Cunha Cavalcante, Francisco Diorge de França

Instituto Federal do Pará (IFPA), BR 316, Km 61,Saudade II, CEP 68740-970, Castanhal, PA, Brazil
Instituto de Ciências Agrárias, Universidade Federal Rural do Semi-Árido (UFERSA), Av. Francisco Mota, 572, Costa e Silva, CEP 59625-900, Mossoró, RN, Brazil
Instituto de Ciências Agrárias, Universidade Federal Rural da Amazônia (UFRA), Av. Perimetral, 2501, Terra Firme, CEP 66077-830, Belém, PA, Brazil

Abstract
Jambu is a plant species from the northern region of Brazil, where it is widely used in food as a seasoning in typical regional dishes, and in folk medicine. The objective of this work was to evaluate the agronomic performance of jambu under organic fertilization. The experiments were conducted under field conditions for the periods January to February, 2015 (Period 1) and May to June, 2015 (Period 2), in soil classified as dystrophic yellow latosol of medium texture. The experimental design was randomized complete block, using a 2 x 5 factorial scheme, with four replicates. The treatments consisted of two jambu accesses (Purple Flower and Yellow Flower), and six doses of organic fertilizer (0, 2, 4, 6, 8, and 10 kg m-2) produced from a mixture of organic compost (mixture of leaves of Syzygium malaccense, Inga edulis, Mangifera indica, and Zoysia japonica) and vermicompost in a volume ratio of 1:1. The following characteristics were evaluated: plant height, fresh mass, and productivity. The best jambu agronomic performance (in terms of yield) was obtained with the application of 10 kg m-2 of organic fertilizer, with higher productivity in the cultivation performed between May and June, 2015. The Yellow Flower access was more productive than the Purple Flower access.

Pages 151-156 | Full Text PDF| doi: 10.21475/ajcs.18.12.01.pne819
…………………………………………………………………………………………………………………………………………………………………………………..

Application of secondary traits in barley for identification of drought tolerant genotypes in multi-environment trials

Aram Arshadi, Ezzat Karami*, Asgar Sartip, Mehdi Zare

Department of Agronomy and Plant Breeding, Campus of Agriculture and Natural Resources, Razi University, Kermanshah, Iran
Department of Agronomy and Plant Breeding, College of Agriculture and Natural Resources, Islamic Azad University, Sanandaj Branch, Sanandaj, Kurdistan, Iran
Department of Agriculture, Firoozabad Branch, Islamic Azad University, Firoozabad, Iran

Abstract
Discriminant function analysis (DFA) is a biometric method that can be used by breeders to distinguish between drought tolerant genotypes. Drought stress is one of the major limiting factors that reduce crop production in semi-arid and arid regions around the world. A multi-environment trial was conducted on barley to investigate various phonological and morphological characteristics under both drought stress and irrigated conditions. Ten indigenous barley genotypes were evaluated in four cropping seasons and in two locations of Iran. Genetic variation was observed in all traits. The traits observed in all genotypes were significantly different. The average broad sense heritability predicted for secondary traits (0.88) was significantly more than grain yield (0.62). The results could significantly discriminate between low and high yield genotypes under drought stress by describing eight secondary traits including biomass, spike weight, grain numbers per main spike, grain numbers per plant, awn length, days to flowering, grain filling period and potential yield. High yield genotypes were selected by discriminant analysis (Eq. (1)). The discriminant score (DS) could explain 67% of grain yield variations and had a significant correlation (r=0.82**) with the average of grain yield examined under drought stress over four years. Consequently, integrated selection can be used as a reliable approach to future breeding programs. Results of DFA indicated that the most important traits, in order of appearance, are awn length, grain filling period, spike weight, and grain numbers per main spike. The results demonstrated that secondary traits could be considered as proper criteria to improve the genetic gain of grain yield and to select tolerant cultivars for environments that are susceptible to drought.

Pages 157-167 | Full Text PDF| doi: 10.21475/ajcs.18.12.01.pne869
…………………………………………………………………………………………………………………………………………………………………………………..

Overcoming seed dormancy and evaluation of viability in Leucaena leucocephala

Regina Soares Bichoff, Amanda Nogueira de Albuquerque, Daiane de Cinque Mariano, Ricardo Shigueru Okumura*, Rudson Silva Oliveira, Cândido Ferreira de Oliveira Neto, Ismael de Jesus Matos Viégas, Augusto José Silva Pedroso, José Darlon Nascimento Alves, Diego Correia Sodré, Gislayne Farias Valente

Department of Agronomy, University of State of Mato Grosso, Tangará da Serra city, Highway MT 358, CEP 78300-000, Brazil
Institute of Agrarian Sciences, Federal Rural University of Amazônia, Parauapebas city, Highway PA 275, CEP 68515-000, Brazil
Department of Agronomy, Federal Institute of Pará, Castanhal city, Highway BR 316, CEP 68740-970, Brazil

Abstract

Leucaena leucocephala is an arboreal legume with many applications in agriculture (forage, wood production, charcoal, soil improvement, shading, windbreak, and hedge). Its seeds show dormancy, which is caused by physical blockade through resistant and impermeable integument. The aims of this study were to evaluate and determine efficient methods for overcoming dormancy in Leucaena leucocephala seeds. The experiment was carried out in Tangará da Serra city, Brazil, adopting a completely randomized design, with four replications. The treatments consisted of no scarification (T0), scarification with sandpaper (T1), immersion in concentrated H2SO4 for 5 min (T2), 10' (T3), 15' (T4), and 20' (T5), and immersion in water at 80°C for 5' (T6), 10' (T7), 15’ (T8) and 20' (T9). The seeds were placed in germination chamber at a temperature of 25ºC and photoperiod of 12 hours day/night over a period of 10 days, for all treatments, using 50 seeds per replicate. The experimental data were submitted to analysis of variance (type I error) by F test (p<0.05) with comparison of averages performed by Tukey test (p<0.05). The treatment that showed best efficiency in overcoming seed dormancy was immersion in concentrated H2SO4 (density of 1.84 and purity of 95%) for 20 min, with 93.0% of viable seed germinated. Immersion of seeds in water at 80ºC for 20 min (0.0% seed germination) showed lowest efficiency in overcoming dormancy of Leucaena leucocephala seeds. It was concluded that treatment with immersion in concentrated H2SO4 for 20 min is the most efficient in overcoming dormancy of Leucaena leucocephala seeds, showing higher values of first germination count, germination percentage, germination speed index and average time of germination.

Pages 168-172 | Full Text PDF| doi: 10.21475/ajcs.18.12.01.pne908

RSS