australian journal of crop science   AJCS

Response of Cratylia argentea (Desvaux) O. Kuntzeto inoculation with Rhizobium sp. and Bradyrhizobium sp. strains

Eduardo P. L. Mattar*, Tiago T. V. Barros, Bruno P. Brasileiro, Edson M. Mattielo, Marcia R. R. Coelho, Guilherme F. V. Gama, Denise C. F. dos S. Dias

Multidisciplinary Center, Federal University of Acre, Road Canela Fina, s / No, Cruzeiro do Sul, Acre, Brazil
Department of Plant Production, Federal University of Viçosa, Avenue Peter Henry Rolfs, s / No, Viçosa, Minas Gerais, Brazil
Department of Plant Production, Federal University of Paraná, Road Funcionários, 1540, Curitiba, Paraná, Brazil
Department of Soil and Plant Nutrition, Federal University of Viçosa, Avenue Peter Henry Rolfs, s / No, Viçosa, Minas Gerais, Brazil
Embrapa Agrobiologia, Highway BR-465, Km 7, s / No, Seropédica, Rio de Janeiro, Brazil


Abstract
Cratylia argentea is a neotropical leguminous shrub that exhibits symbiosis with nitrogen (N) fixing bacteria and high levels of protein. Thus, it has potential for animal feed and green manure. In spite of its potential, few cultivars are registered for the species and there is little information in regard to its interaction with N-fixing microorganisms. The aim of this study was to evaluate the effect of inoculation with rhizobium strains on the growth and concentration of N in Cratylia argentea. Seeds were inoculated with two strains of Rhizobium sp.,CR 33 (BR10243) and CR42 (BR10244), and four strains of Bradyrhizobium sp., CR52 (BR10257), CPAC-B10, SEMIA 6464 (BR3262), and SEMIA 6462 (BR3267), and sown in pots filled with sand and vermiculite in a greenhouse. After 150 days we evaluated the number of nodules, shoot and nodules dry matter, total nitrogen and crude protein contents for the shoots. The plants inoculated with CR 52 exhibited nodulation, with nodular efficiency of 0.189 and relative efficiency of 66.14%; it is possible to observe the effect of nodulation as of 85 days after sowing. Based on the obtained results it was identified the strain that showed symbiosis with C. argentea and presents potential to be used as a commercial inoculant.

Pages 849-854 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE524
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Differential response of an international rice (Oryza sativa L.) collection to drought simulated stress (PEG) at vegetative stage

Malihe Eslami, Asadollah Ahmadikhah*, Mohamad-Reza Azimi, Abbas Saeidi

Department of agronomy and plant breeding, Faculty of agriculture, Zanjan University, Zanjan, Iran
Department of Plant Sciences and Biotechnology, Faculty of Life Sciences and Biotechnoogy, Shahid Beheshti University, Tehran, Iran


Abstract
Drought is one of the major abiotic stresses that affects different stages of plant growth and development, especially germination and seedling growth. In order to assess drought stress effect on germination and seedling growth of rice, an experiment was performed at three levels of Polyethylene glycol (PEG-6000) (0, -0.6 and -0.8 MPa) on an international rice collection consisted of 93 varieties. Seven drought tolerance indices including STI, SSI, HM, RDI, SSPI, ATI and TOL were used to identify drought tolerant genotypes. The results of variance analysis showed that the effect of genotypes (G), drought stress (D) and G×D interaction were significant for all investigated traits. With increasing of stress level most genotypes showed similar trend of drought response, i.e. reduction in all traits. The results also revealed that dry weight (DW) was less affected than fresh weight (FW), and the shoot weight (SW) was affected more than the root weight (RW), indicating that shoot growth is more sensitive than root growth to drought stress. The highest correlation (0.91) was observed between shoot fresh weight (SFW) and shoot dry weight (SDW), while the least correlation (0.01) was found between germination rate (GR) and root fresh weight (RFW) and root:shoot length ratio (RL:SL). Among the drought-related indices, the highest correlation was observed between STI and plant performance (Z-scores) under both optimal and stress conditions, thus STI can be used as the most suitable indicator for screening drought tolerant genotypes. Based on the results, genotypes #191 (RTS4), #171 (Paraiba Chines Nova) and #164 (Padi Kasalle) showed the highest performance and STI under drought condition, so they have considerable potential to improve drought tolerance in rice breeding programs. In addition, genotypes #136 and #140 with the lowest values of STI were found to be intolerant genotypes to drought stress.

Pages 855-869 | Full Text PDF| Supplementary Data| doi: 10.21475/ajcs.18.12.06.PNE545
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Rice grain quality as affected by blast-causing agent (Pyricularia oryzae) along with a molecular analysis of blast resistance at Pi5 and Pi-ta loci

Asadollah Ahmadikhah*, Vahid Khosravi

Department of Plant Sciences and Biotechnology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran
Plant Pathology Section, Rice Research Institute, Amol, Mazandarn, Iran


Abstract
Blast disease is the most devastating disease of rice worldwide, which reduces both quantity and quality of rice production. To assess the effect of fungal agent of blast, Pyricularia oryzae, on some aspects of grain quality of rice, 31 rice cultivars (including 20 local landraces) were evaluated at seedling and post-harvest stages. The cultivars were grown in three replicates in a field surrounded by blast spreader cultivars and at appropriate times blast infection type, grain infection, 100-grain weight and grain quality traits (percentage of broken rice and number of chalky seeds per panicle) were evaluated. For tracking alleles of two major blast resistance genes (including Pi5 and Pi-ta) the respective primer pairs were applied in a polymerase chain reaction (PCR) on DNA of the studied cultivars. Evaluation of blast infection type at seedling stage showed that four cultivars were completely resistant, 4 cultivars moderately resistant and 23 cultivars mainly consisted of local landraces were susceptible. Fungal treatment had significant effects on percentages of grain infection and broken rice and not on number of chalky seeds or 100-grain weight. Rice genotypes had significant differences in grain infection and also in 100-grain weight and in two quality traits including percentage of broken rice and number of chalky seeds. Most local landraces showed highest grain infection (14.4-17.6%) compared to improved modern varieties with lowest grain infection (1.3-2.7%). Results also showed that genotype by fungal treatment interaction were only significant for grain infection and broken rice. All susceptible cultivars had higher broken rice relative to resistant cultivars (10.5-13.3% vs. 2.1-4.6%) after blast infection. Molecular survey showed that most susceptible local landraces carry Pi5 dominant allele, while high-yielding modern cultivars don’t carry the allele, indicating that Pi5 does not play a significant role in blast resistance at this time. Furthermore, molecular survey showed that only three cultivars including a local cultivar (Tetep) and two modern ones (IR56, IR24) harbored Pi-ta allele, and Pi-ta explained a high part of variation of blast resistance (R2=53.7%). These results indicate the importance of Pi-ta gene for improving rice blast-resistance and grain quality at blast infection conditions.

Pages 870-877 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE596
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Effects of Murumuru (Astrocaryum murumuru Mart.) and soybean biodiesel blends on tractor performance and smoke density

Murilo Coelho Theodoro Neves*, Afonso Lopes, Melina Cais Jejcic de Oliveira, Priscila Sawasaki Iamaguti, Thyago Augusto Medeiros Lira, Thaisa Calvo Fugineri Moreti, Leomar Paulo de Lima, Gilberto Hirotsugu Azevedo Koike

Universidade Estadual Paulista – UNESP - Campus Jaboticabal/SP, Brazil

Abstract
The usage of biodiesel, a renewable and biodegradable fuel, is becoming increasingly popular. The objective of the study was to evaluate the operational performance—tractor forward speed, drawbar power, and fuel consumption—and smoke density of an agricultural tractor using biodiesel, diesel, and biodiesel/diesel mixtures as fuel in a tilled field. Soybean biodiesel, murumuru biodiesel, and three combinations of soybean biodiesel and murumuru were used: 90S10M (90% soybean and 10% murumuru), 80S20M (80% soybean and 20% murumuru), and 70S30M (70% soybean and 30% murumuru). The biodiesel/diesel ratios were: B0, B5, B15, B25, B50, and B100; the letter B indicates the presence of biodiesel and the number is the percentage of biodiesel in the diesel. The results showed an increase in specific fuel consumption (SFC) of 10.13%, 16.66%, 12.69%, 14.59%, and 17.42% for murumuru, soybean, 90S10M, 80S20M, and 70S30M, respectively, when comparing B100 to B0. SFC was influenced by the type of biodiesel, B100 of soybean, 90S10M, 80S20M, and 70S30M consumptions were, respectively, 7.8%, 2.9%, 5.2%, and 8.8% higher than those of murumuru. The hourly volumetric consumption (HVC) of 90S10M was 4.8% higher than soybean and murumuru. The tractor’s forward speed and drawbar power did not have any significant difference. Smoke density was reduced by 51.6%, 23.04%, 30.41%, 37.8%, and 36.9% for Murumuru, Soybean, 90S10M, 80S20M, and 70S30M, respectively, when comparing B100 to B0. For Murumuru, the smoke density was 59.0%, 43.8%, 28.6%, and 30.5% lower for this variety of biodiesel when compared to soybean at 90S10M, 80S20M and 70S30M, respectively. The results demonstrate the potential usage of biodiesel as a substitution for diesel.

Pages 878-885 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE634
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Correlations between agronomic traits in papaya tree (Carica papaya L.) grown under subtropical climate of Brazil

Marcelo de Souza Silva, Sarita Leonel, Jackson Mirellys Azevêdo Souza, Rafael Bibiano Ferreira, Ana Carolina Batista Bolfarini, Marcelo Almeida de Oliveira Júnior

Department of Horticulture, Universidade Estadual Paulista (UNESP), Botucatu, Brazil

Abstract
The current study aimed at evaluating the correlations between agronomic traits in papaya trees grown under Brazilian subtropical climate. A randomized block design with three treatments (Sunrise Solo, Tainung nº1 and Local variety) was used. The experiment was laid out in seven blocks and five plants per plot. The following traits were assessed: plant height; insertion height of the first fruits; stem diameter; male, female, and hermaphrodite plants percentage; fruit number per plant; production; yield; percentage of normal fruits; carpelloid and pentandric fruits percentage; internal cavity diameter; fruit matter; pulp and seed yield; seeds number; soluble solids; titratable acidity; ratio and technological index. Results indicated that seed performance can be used as indirect selection criteria for genetic improvement of Sunrise Solo seeds (correlation between SP and FNP, PRO, YIELD and PNF of 0.97, 0.96, 0.96, -0.89, respectively). Carpelloid fruits exhibited a positive correlation with production traits, but negative correlation with physicochemical traits in papaya fruits. Moreover, there is a modest correlation between physicochemical and productive traits of Tainung nº1 and Local Variety fruits.

Pages 886-891 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE840
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Soybean yield performance associated with seed size, type of fertilizers and furrow openers

Maicon Sgarbossa*, Jean Carlo Possenti, Carlos André Bahry, Alcir José Modolo

Postgraduate Program in Agronomy, Federal University of Technology – Paraná (Universidade Tecnológica Federal do Paraná - PPGAG/UTFPR), Pato Branco – PR, Brazil
Department of Agronomy, Federal University of Technology – Paraná (Universidade Tecnológica Federal do Paraná – UTFPR), Dois Vizinhos – PR, Brazil


Abstract
There is some doubt about the influence of seed size among soybean producers, who often believe that larger seeds produce more vigorous plants. There is also some debate regarding the furrow opener, as it influences the depth of the fertilizer in relation to the seed. This study aimed to evaluate seeding parameters and the development and productivity of the soybean in regard to seed size and employing fertilizer furrow opener. The experiment was conducted in a typical distroferric red nitisol with very clayey texture in two crop seasons 2014/2015 and 2015/2016. The experiment adopted a randomized block design in a factorial structure, with five replications. Treatments consisted of the combination of two seed sizes of Nidera® NS 4823 RR cultivar (large - 6.5 mm, and small - 5.5 mm in diameter) and two types of furrow opener (shank and double disc). The use of shank-type furrower resulted in a greater mobilized area and a greater sowing depth in both seasons. Due to environmental conditions, smaller seeds resulted in lower plants, 30 days after sowing and fewer pods per plant in the first studied season. In turn, seeds with larger diameter resulted in higher productivity in the second season, although in the first year there was no significant difference.

Pages 892-897 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE846
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Quality of sweet potato cultivars planted harvested at different times of two seasons

José Ricardo Tavares de Albuquerque, Rayanne Maria Paula Ribeiro, Leonardo Vieira de Sousa, Giordanio Bruno Silva Oliveira, Hamurábi Anizio Lins, Aurélio Paes Barros Júnior, Elizangela Cabral dos Santos, Patrícia Ligia Dantas de Morais, Adriano do Nascimento Simões*

Departament of Crop Science, Universidade Federal Rural do Semi-Árido (UFERSA), Av. Francisco Mota, 572, Costa e Silva, CEP 59625-900, Mossoró, RN, Brazil
Centro de Ciências Agrárias (CCA), Universidade Federal da Paraíba (UFPB), Centro de Ciências Agrárias, Campus II, CEP 58397-000, Areia, PB, Rodovia BR 079, Km 12, Brazil
Unidade Acadêmica de Serra Talhada (UAST), Universidade Federal Rural de Pernambuco (UFRPE), Av. Gregório Ferraz Nogueira, S/N, José Tomé de Souza Ramos, CEP 56909-535, Serra Talhada, PE, Brazil


Abstract
This study aimed at adapting harvest time of different potato cultivars in two seasons during the year. Two experiments were conducted: one in the rainy season and another in the dry period. Two production factors were studied in experiments using a split-plot design in a complete randomized block design. The first factor (including 3 sweet potato cultivars: ESAM 1, Paraná and Mãe de Família) was assigned to the plots. The second factor (harvest time: 90, 105, 120, 135 and 150 days after planting) was assigned to the subplots. Soluble solids, total soluble sugars, starch content, pulp firmness, cooking time and vitamin C were assessed. The harvest after 150 days resulted in increased levels of soluble sugars, starch, and vitamin C in both growing seasons, compared to other harvests, demonstrating that tuberization does not depend on season. In addition, late harvesting increased the cooking times with all cultivars, especially those grown in the rainy season. In the dry season, cooking time was higher for cv. ESAM 1. Of the three sweet potato cultivars, cv. Parana presented the highest total amount of soluble sugars and vitamin C, as well as faster cooking time, while cv. ESAM 1 had the highest starch content, pulp firmness and the longest cooking time. The results suggest that Paraná and Mãe de Família are feasible for the fresh market and ESAM 1 for industry, regardless of the season or harvest time. These cultivars offer growers flexibility when deciding on sweet potato crops for different purposes, i.e. fresh market or industry. Delaying the harvest of sweet potatoes until 150 days gives greater flexibility to producers in the semi-arid region of Brazil in relation to either fresh or the industrial market.

Pages 898-904 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE884
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Antimalarial, antioxidant, antimicrobial properties of Moringa Oliefera Lam: A review

Abdulaziz Rabiu Abdulkadir, Md Mainul Hasan, Md Sarwar Jahan*

Faculty of Bioresources and Food Industry, Universiti Sultan Zainal Abidin, 22200, Besut, Terengganu, 22200 Malaysia
Department of Agricultural Botany, Faculty of Agriculture. Patuakhali Science and Technology University, Dumki, Patuakhali, 8602 Bangladesh


Abstract
Moringa oliefera Lam (Moringa) has antimalarial, antioxidant, antimicrobial as well as nutritional properties. Different parts of Moringa was used as a folk medicine to cure certain diseases ranging from venomous bites, rheumatism, ascites, circulatory stimulant among. Previous studies showed that different parts of Moringa oleifera have shown various pharmacological properties. However, there is a gap where substantial information is to be updated in the area of antimalarial, antioxidant, antimicrobial effect of the plants. Nevertheless, some part of the plant such as leaves and fruits have been used as vegetables, which serve as an excellent source of vitamins, beta-carotene, calcium, iron, riboflavin and phenolic acid. Therefore, there is an affirmative action that the plant has a vast antimalarial, antioxidant, antimicrobial activity to cure different diseases.

Pages 905-908 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE920
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Watermelon fruit production and characterization affected by molybdenum (Mo) and other micronutrient fertilization

Elaine Heberle, Daniela Vieira Chaves*, Renato Falconeres Vogado, Firmino Nunes de Lima, Joelma Francisca de Moura Lima, Fernando Luiz Finger

Federal University of Piauí (UFPI), Campus Professora Cinobelina Elvas (CPCE), Bom Jesus, 64900-000, Piauí, Brazil
Federal University of Paraíba (UFPA), Areia, Paraíba, Brazil
Federal University of Brasília (UNB), Brasília, Brazil
Federal Institute of Maranhão (IFMA), São Raimundo das Mangabeiras, Maranhão, Brazil
Federal University of Viçosa, (UFV), Viçosa, Minas Gerais, Brazil


Abstract
Micronutrients are essential for the development of plants and may affect the quantity and quality of the products of interest. This study aimed to evaluate the effects of foliar fertilization with molybdenum and other micronutrient on ‘Olímpia’ watermelon fruit yield and quality. The experiment was carried out following a randomized block design, with treatments in a 4 x 2 factorial scheme, for molybdenum doses (0, 15, 30, and 60 g Mo ha-1) and Kit presence or absence, with four replications. The number of fruits per plant, yield per plant, commercial productivity, average fruit mass, longitudinal and transverse diameters, peel thickness, and pulp yield were evaluated. Molybdenum foliar fertilization increased the yield per plant and the fruit diameters, with the best results at dose of 30 g Mo ha-1. The Kit promoted higher productivity per plant (25.7%), fruits with higher pulp yield (5.3%) and lower peel thickness (11.07%). Joint molybdenum and Kit application increased watermelon fruit pulp yield by 5.7% at 30 g Mo ha-1, and up 8.4% at higher doses. Foliar fertilization with 30 g Mo ha-1 and other micronutrients improve the ‘Olímpia’ watermelon fruit yield and quality being recommended to producers.

Pages 909-914 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE922
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Biometrics, productivity and technological quality of 23 energy sugarcane hybrid clones with higher lignocellulosic biomass

João Paulo de Lima Silva*, Gisele Silva de Aquino, Deisi Navroski, Ítalo Francisco de Souza, Hugo Lyra Soriano, José Antônio Bressiani, Ricardo Ralisch

State University of Londrina (UEL), Department of Agronomy, Celso Garcia Cid Highway, s/n, Zip Code 10011 – CEP 86057-970, Londrina – PR, Brazil
Usina Caeté – Unidade Paulicéia, Estrada Municipal de Paulicéia a São João do Pau D’alho, km 7, 17.900- 000, Paulicéia, São Paulo, Brazil
GranBio Investimentos AS, Av. Brig. Faria Lima, 2277, cj. 1503, Alto de Pinheiros, São Paulo 01452-000, SP, Brazil


Abstract
The development and identification of sugarcane clones with higher amount of lignocellulosic biomass are essential to increase the potential for generation of electrical energy or biofuel. Considering the potential for increased portfolio of products to be explored from the cane energy, the objective of this study was to compare the average results of biometrics, productivity and technological quality of 23 hybrids of cane energy with the commercial variety RB92579 (as a standard). Finally, we will identify energy cane clones of types 1 and/or 2 to become commercial cultivars. The experimental design was randomized blocks with three replications of 24 plots, where each plot consisted of 6 furrows of 10 linear meters with double spacing cycled from 0.9 x 1.5 meters. The evaluated variables were the number of stems per linear meter, stem diameter, dry and fresh matter and industrial quality. The results were submitted to statistical analysis using the Scott-Knott test for comparison of means. The diameter of stem in energy cane was lower (1.172 to 1.772 cm) than the average of sugarcane (2.302 cm). On the other hand, a greater number of stems per linear meter were found for 15 clones evaluated (average 24.19) compared to traditional sugarcane (12.5). All clones had low juice sugars concentration but nine clones reached fiber contents higher than 23.6%, representing a 42% increase compared to the fiber content of cultivar RB92579. The hybrids 1, 9, 11, 13, 16, 18 and 23 showed a better development potential with high tillering and high fiber content.

Pages 915-921 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE936
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Carbon stock variability and aggregate stability in soils of Amazon, Brazil

Ivanildo Amorim de Oliveira, Milton César Costa Campos*, Ludmila de Freitas, Renato Eleotério de Aquino, José Maurício da Cunha, Marcelo Dayron Rodrigues Soares, Laércio Santos Silva, Julimar da Silva Fonseca, Douglas Marcelo Pinheiro da Silva, Zigomar Menezes de Souza, Fernando Gomes de Souza

Instituto Federal do Pará – IFPA, Rua Antônio Fulgêncio da Silva, s/n , 68.800-000 Breves – Pará, Brazil
Universidade Federal do Amazonas - IEAA, Rua 29 de Agosto, 786, 69.800-000 – Humaitá/AM/Brazil
Universidade Estadual Paulista - FCAV, Via de Acesso Prof. Paulo Donato Castellane s/n, 14.884-900, Jaboticabal/SP/Brazil
Universidade Federal do Amazonas - IEAA, Rua 29 de Agosto, 786, 69.800-000 – Humaitá/AM/Brazil
Universidade Estadual de Campinas - FEAGRI, Av. Cândido Rondon, 501, Barão Geraldo, 13.083-875, Campinas/SP/Brazil


Abstract
Converting natural ecosystems into agro-ecosystems often reduces soil organic carbon content by decreasing carbon input, as well as by increasing erosion losses and organic matter decomposition rate. This study aimed at evaluating carbon stocks, soil aggregate stability, and spatial variability of some other attributes in soils of Southern Amazonas state. The study was carried out on areas with archaeological dark earth (ADE), under rainforest, pasture, agroforestry environments, sugarcane, and cassava. We collected disturbed and undisturbed soil samples from 64 points in a regular spacing of 10 m at 0.0-10 cm depth. From these samples, we determined the stock of organic carbon (STOC), organic carbon (OC), organic matter (OM) content, soil aggregate stability (SAS), and soil bulk density (SBD). Data analysis included univariate, multivariate, and descriptive statistics. The STOC was higher in ADEs and the adjusted semivariograms pointed out a greater spatial variability for soils under pasture and cassava crop. Kriging maps of principal component analysis scores proved a positive correlation between the studied variables and terrain slope, with higher values for lower lands.

Pages 922-930 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE961
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Application of nanomaterial graphene oxide on biochemical traits of Milk thistle (Silybum marianum L.) under salinity stress

Sara Safikhan, Mohammad Reza Chaichi, Korous Khoshbakht*, Abbas Amini, Babak Motesharezadeh

Department of Agroecology, Shahid Beheshti University, Environmental Sciences Research Institute, Shahid Beheshti University, Evin, Tehran, Iran
Department of Crop Science, College of Agriculture, California State University, Pomona, USA
Department of Computing, Engineering, and Mathematics, Western Sydney University, Kingwood Campus, Locked Bag 1797, Perth, NSW 2751, Australia
Department of Soil Science and Engineering, College of Agriculture and Natural Resources, University of Tehran, Karaj, Iran

Abstract
In recent years, application of engineered nanomaterials, in particular carbon-based nanostructures, has been initiated in agriculture. To better understand the effects of nanomaterials on plants, four concentrations of graphene oxide (0, 0.01, 0.05, 0.1%) in soil was studied on growth and biochemical traits of Milk thistle under four saline stress (0, 4, 8,12 dS/m) conditions in greenhouse. A completely randomized block design with a factorial treatment arrangement was employed with three replications. The result showed under both saline and control (non-saline) conditions, the maximum plant height (3.7% and 20% in control and saline conditions, respectively), total biomass (17% and 8.2% in control and saline conditions, respectively), and chlorophyll content (8% and 5% in control and saline conditions, respectively), were achieved for plants with graphene oxide (GO) application. By increasing the salinity level, plants treated with 0.01% concentration of graphene oxide produced the highest total biomass (518 mg) under 12 dS/m salinity levels. Also, maximum quantum efficiency of PSII, performance index, and membrane stability index decreased due to salinity stress. Proline and soluble carbohydrates noticeably increased by saline water treatments. Graphene oxide alleviated salt stress-induced damage through increasing plant growth, plant height, chlorophyll content, photosystem efficiency, performance index, membrane stability index, proline and soluble carbohydrate content. Also graphene oxide increased cell water potential through enhancing the net concentration of solutes in plant cells. Graphene nanomaterials could ameliorate the salt stress in Milk thistle plant. Graphene oxide application could be commercially and economically beneficial for Milk thistle production under control and saline conditions.

Pages 931-936 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE972
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The physiological quality of the seeds of passion fruit (Passiflora spp.) grown at different altitudes

Khétrin Silva Maciel, Paula Aparecida Muniz de Lima, Fernando Zanotti Madalon, Simone de Paiva Caetano Bucker Moraes, Rodrigo Sobreira Alexandre, José Carlos Lopes*

Postgraduate Program in Plant Production, Federal University of Espírito Santo (Universidade Federal do Espírito Santo), Alegre, Espírito Santo, Brazil
Department of Forest Sciences, Federal University of Espírito Santo (Universidade Federal do Espírito Santo), Alegre, Espírito Santo, Brazil
Department of Plant Production, Federal University of Espírito Santo (Universidade Federal do Espírito Santo), Alegre, Espírito Santo, Brazil

Abstract
Altitudes, ranging between 100 m and 900 m are the most suitable for growing passion fruit and the studies on the distinct geographical locations suggest the expression of different genotypes under the influence of adequate environmental conditions. The objective of this study was to evaluate the physiological quality of the seeds of Passiflora spp., cultivated at three different altitudes in the state of Espírito Santo, Brazil. Before conducting the physiological tests for seed quality, pre-tests were performed on the physically scarified, gibberellic acid-treated, and intact seeds of the yellow passion fruit (Passiflora edulis Sims f. flavicarpa Degener), the purple passion fruit (Passiflora edulis Sims), and the sweet passion fruit (Passiflora alata Curtis), collected from three different altitudes (high, medium, and low), in order to overcome dormancy. The higher values of germination and vigor were observed after the pre-germination treatments of the intact seeds of the yellow passion fruit, the scarified seeds of the purple passion fruit, and the gibberellic acid-treated seeds of the sweet passion fruit. The seeds with the highest values of germination and vigor were selected for the accelerated aging test with a saturated salt solution at 43 ºC for 72 h and the controlled deterioration test with 25% of moisture at 45 ºC for 24 h, respectively. Using these tests, it was possible to differentiate the species of passion fruit, collected from different altitudes. The seeds of the yellow passion fruit and the seeds, collected from higher altitudes presented higher physiological quality in this study.

Pages 937-942 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE987
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Inducing salt tolerance in castor bean through seed priming

Lineker de Sousa Lopes, José Tarquínio Prisco, Enéas Gomes-Filho*

Departamento de Bioquímica e Biologia Molecular and Instituto Nacional de Ciência e Tecnologia em Salinidade (INCTSal)/CNPq, Universidade Federal do Ceará, Brazil
Departamento de Bioquímica e Biologia Molecular and Instituto Nacional de Ciência e Tecnologia em Salinidade (INCTSal)/CNPq, Universidade Federal do Ceará, mailbox 6039, zip code 60440-554, Fortaleza, CE, Brazil


Abstract
Castor bean (Ricinus communis L.) cultivation requires production techniques appropriate for its growth conditions. Thus, the characterization of the deleterious effects of salinity on seed germination and on seedling establishment and the evaluation of the use of priming techniques on seeds could reduce replanting costs and improve emergence uniformity, preparing plant responses to salt stress. The goals of this current research were to characterize the deleterious effects of salinity on seed germination and on seedling establishment and to evaluate the use of the seed priming techniques as a tool to minimize these deleterious effect. In this research, castor bean seeds, cv. BRS-Energia was used to characterize effects of salt stress on germination and seedling establishment. Then, some chemicals such as PEG-6000 and H2O2 were evaluated to find the beneficial priming techniques for castor bean seeds against salt stress. Our results indicate that water imbibition by the seed under salinity conditions decelerated the time of exposure to salinity. Salinity also affected the germination of castor bean seeds under an Ψs of -0.4 MPa and seedling growth was already affected under an Ψs of -0.16 MPa. Priming with CaCl2, NaNO2, NaNO3 and PEG-6000 showed promising results under an Ψs of 0.0 MPa, but priming with NaNO3 and PEG-6000 were ones that contributed most to better germination and establishment of seedlings under saline conditions. However, NaNO3 is the most recommended priming agent for castor bean because accelerated seed germination, reducing the time to emergence and planting risks.

Pages 943-953 | Full Text PDF| Supplementary Data| doi: 10.21475/ajcs.18.12.06.PNE1011
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Germination of guar (Cyamopsis tetragonoloba (L.) Taub.) genotypes with reduced temperature requirements

Fabio Gresta*, Antonia Cristaudo, Calvin Trostle, Umberto Anastasi, Paolo Guarnaccia, Stefania Catara, Andrea Onofri

Dipartimento di Agraria, University of Reggio Calabria, Loc. Feo di Vito, 89122, Reggio Calabria, Italy
Dipartimento di Scienze Biologiche, Geologiche e Ambientali, University of Catania, Via Empedocle, 58, 95128 Catania, Italy
Texas A&M AgriLife Extension, Lubbock, Texas USA
4Dipartimento Agricoltura, Alimentazione e Ambiente, University of Catania, Via Valdisavoia, 5 95123 Catania, Italy
Dipartimento di Scienze Agrarie, Alimentari ed Ambientali, University of Perugia, Borgo XX Giugno 74, 06121, Perugia, Italy


Abstract
Guar (Cyamopsis tetragonoloba (L.) Taub.) is an annual legume with a long crop cycle and high temperature threshold for seed germination (20-21°C). In semi-arid Mediterranean areas, inadequate soil warmth delays guar planting to May/early June and harvest to October-November, when high rainfall hinders seed maturation and lowers gum quality. Nine world guar genotypes (from India, Pakistan, USA, South Africa) were tested for germination capability and speed in response to temperature. All source seeds were field grown in Sicily for use in germination assays. The following temperature regimes were imposed adopting a completely randomized design: A) seven constant temperatures from 5°C to 35°C (5°C increments), and B) two alternating temperatures of 15/10°C and 20/15°C (6h/18h thermoperiod), each consisting of four replicates of 25 seeds. Optimal germination temperatures were always 30 and 35°C, but Indian genotypes also demonstrated substantial germination percentages (33-43%) at constant temperatures as low as 15°C. Mean germination time (MGT) of genotypes India2, Kinman, Lewis, and Monument were 1.1 to 1.7 days at 30 and 35°C. At lower temperatures (15°C), the germination percentage and MGT improved significantly when the seeds were exposed at 20°C for 6 hours a day. In particular, Kinman, India2 and Monument gave good results, achieving 80%, 76% and 66% germination, respectively, with MGTs of 5 days. This alternating temperature regime is typical in soil during the Mediterranean spring. Results may be useful both for farmers to identify optimum timing for guar sowing, and for breeders to cross genotypes that tolerate low germination temperatures with high yielding genotypes.

Pages 954-960 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE1049
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Response of Hypothenemus hampei (Coleoptera: Curculionidae) to semiochemicals and blends using baited traps in coffee fields

Moisés Santos de Souza*, José Nilton Medeiros Costa, Marcelo Curitiba Espíndula, Alexandre de Almeida e Silva

BIONORTE-Biodiversity and Biotechnology Network of the Legal Amazon and Federal University of Amazonas - UFAM, Manaus, AM, Brazil
Brazilian Agricultural Research Corporation - Embrapa Rondonia, Porto Velho-RO, Brazil
Federal University of Rondonia - Bioecology of Insects Laboratory, Porto Velho-RO, Brazil


Abstract
Hypothenemus hampei (Ferrari) is an important pest of coffee fields all around the world. The understanding of the synthetic attractive volatiles is essential for the development of appropriate strategies for its integrated management. The olfactory response of this insect to ethylene (ETL) and ethyl acetate (EA) was investigated in experimental coffee (Coffea canephora ‘Conilon’) fields in Rondonia, Brazil, using baited traps with single compounds and combined with alcohols, i.e., ethanol:methanol (ET:MT, 1:1). Baited traps were placed along plant rows within the coffee field using a randomized block design. Collected insects were properly separated, counted and identified using a stereomicroscope in the laboratory. Traps baited with EA captured a higher number of H. hampei compared to control traps, suggesting its effect as possible attractant. Despite that, the combination of EA with single alcohols, i.e., EA:ET (1:1) and EA:MT (1:1) and then ET:MT (1:1), i.e., EA:ET:MT (1:1:1) did not increase beetle capture compared with currently used H. hampei attractants, i.e., ET:MT (1:1). Other experiments will be performed to improve bait performance using different EA to ET:MT ratios.

Pages 961-966 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE1057
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Maize productivity cultivated as first crop in succession to different cover crops

Jefferson Luis Anselmo, João William Bossolani*, Edson Lazarini, Aguinaldo Jose Freitas Leal, Rita de Cássia Félix Alvarez, Marcelo Valentini Arf

Fundação de Apoio à Pesquisa Agropecuária de Chapadao do Sul, Chapadao do Sul, MS 79560-000, Brazil
Universidade Estadual Paulista, Ilha Solteira, SP 15385-000, Brazil
Universidade Federal do Mato Grosso Do Sul, Chapadao do Sul, MS 79560-000, Brazil


Abstract
The plant residues left on the soil surface in no-tillage systems are an important source of nutrients for the subsequent crops, particularly under tropical climate. The aim of this study was to evaluate the cover plants grown during the off-season on development and productivity of maize cultivated in the first crop in no-tillage system. The experiment was conducted in the 2010/11 and 2011/12 agricultural years, in the experimental area. The experimental delineation used was the random blocks with four repetitions and eight treatments (as cover crops) consisted as follows: maize (alone), maize + Urochloa ruziziensis, sorghum, Crotalaria spectabilis, Urochloa ruziziensis, forage turnip, millet and fallow. The cover plants were placed in "Litter Bags", which were fixed to the ground in each plot and collected at 0, 15, 45, 75 and 115 days after the handling of the covers. Plant height, first ear insertion height and grain productivity were assessed in the culture of maize. Maize in single cropping or intercropping with Urochloa ruziziensis were good option to cover plants for the no-tillage system, due to maintenance of straw on the soil surface. Maize seeded on crop residues of C. spectabilis and U. ruziziensis showed more plant height; crop residues of forage and U. ruziziensis provided an increase maize culture productivity grown in succession.

Pages 967-974 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE1063
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Effects of soil type and rainwater harvesting treatments in the growth, productivity and morphological trains of barley plants cultivated in semi-arid environment

Abdel Rahman Al-Tawaha, Abdel Razzaq Al-Tawaha, Mohammad Alu’datt, Abdul Latief Al-Ghzawi, Mohammad Wedyan, Sa'doon A. Al-Obaidy, Ezz Al-Dein Al-Ramamneh

Department of Biological sciences, Al-Hussein bin Talal University, Maan, Jordan
Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia
Faculty of Agriculture, Jordan University of Science and Technology, P.O. Box 3030, Irbid, Jordan
Department of Biology and Biotechnology, Faculty of Science, the Hashemite University, Zarqa, Jordan
Department of mathematics, Al-Hussein bin Talal University, Maan, Jordan
Department of Agricultural Sciences, AL-Shouback University College, Al-Balqa Applied University, AL-Shouback, Maan, Jordan


Abstract
Field experiments were conducted in the years 2013/2014 with two soil types from northern part of Jordan. The soil types that were chosen for the study were yellow Mediterranean sandy loam soil (site A) and red Mediterranean silt loam soil (site B). At both sites, a control (untreated soil) and experimental soil (hoops method of rainwater harvesting) was used. Our results indicated that barley plants which were grown in red Mediterranean silt loam soil had higher grain yield, increased number of spikes per plant, high amount of grains per spike, 1000-grain weight, increased plant height and higher spike length than those plants grown at yellow Mediterranean sandy loam soil. On the other hand, barley plants which were grown under water harvesting treatment gave the best results compared to those plants which were grown without water harvesting treatment.

Pages 975-979 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE1075
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Effect of chemical thinning using 6-benzyladenine (BA) on Maciel peach (Prunus persica L.)

Caroline Farias Barreto*, Renan Navroski, Renan Ricardo Zandoná, Roseli de Mello Farias, Marcelo Barbosa Malgarim, Paulo Celso de Mello-Farias

Departamento de Fitotecnia, área de Fruticultura de Clima Temperado, Universidade Federal de Pelotas, Capão do Leão, RS, Brasil
Departamento de Fitossanidade, Universidade Federal de Pelotas, Capão do Leão, RS, Brasil


Abstract
High effective peach fruit set results in an excessive amount of fruits, requiring thinning accomplishment, which is a manual practice and demands specialized labor, raising production costs. In this sense, chemical thinning may be an alternative to improve the peach production chain. The objective of this work was to evaluate the efficiency of 6-benzyladenine (BA) on chemical thinning and the effect of different BA dosages on peach production and color characteristics of ‘Maciel’ fruits. Treatments consisted of plants without thinning (Control), sprayed BA at doses of 100 mg L-1, 200 mg L-1 and 400 mg L-1, applied 45 days after full bloom (DAPF) and hand thinning at 45 DAPF. The applications of different dosages were carried out by spraying, using backpack spraying equipment. Percentage of thinning abscission, number of fruits per plant, yield per plant, fruit mass, color and average fruit diameter were evaluated. The doses of 200 and 400 mg L-1 BA for thinning increased the percentage of fruit abscission and fruit mass. The doses of 400 mg L-1 BA presented lower yield per plant, but fruits with higher average mass. Increasing BA dose reduced the number of fruits per plant. Hand thinning and 400 mg L-1 BA resulted peach fruits with larger diameter. BA application to thin peaches did not alter the fruit skin color. Therefore, BA may be a chemical thinning alternative for ‘Maciel’ peach cultivar, because it reduces the time of thinning in plants when compared to manual thinning. For an efficient chemical thinning with BA the product dose must be taken into account, along with climatic conditions and the cultivar.

Pages 980-984 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE1086
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Ryegrass (Lolium multiflorum Lam.) seed germination and vigor under saline stress

Aline Klug Radke*, Paulo Eduardo Rocha Eberhardt, Andrea Bicca noguez Martins, Fernanda da Motta Xavier, Vanessa Pinto Gonçalves, Michele Renata Revers Meneguzzo, Carlos Eduardo da Silva Pedroso, Francisco Amaral Villela

Departamento de Fitotecnia, Programa de Pós- Graduação em Ciência e Tecnologia de Sementes, Faculdade de Agronomia Eliseu Maciel, Universidade Federal de Pelotas. FAEM/UFPel, Caixa postal 354, 96010-900 - Pelotas, RS, Brasil

Abstract
Ryegrass (Lolium multiflorum Lam.) is forage with the potential to increase pasture area in Southern Brazil. It is an option for more profitable and intensive use of floodplain areas during the cold seasons of the year. However, irrigation of crops in these areas in the summer can result in the salinization of the soils that have inadequate drainage, preventing the removal of salt by leaching. The objective of this study was to evaluate the performance of ryegrass seeds using different concentrations of sodium chloride. Four commercial ryegrass cultivars of PGG Wrightson Seeds Brazil were used: Inia Bakarat, Inia Scorpio, Inia Camaro, and La Estanzuela 284. Saline substrates consisted of Germitest® paper wetted with sodium chloride solution at five osmotic potentials (0, -0.2, -0.4, -0.6 and -0.8 MPa). The study was conducted at the "Flavio Rocha" Didactic Seeds Analysis Laboratory and involved analysis of the following indicators of salt stress response: germination (%), first germination count (%), plantlet length (cm), and plantlet dry phytomass (mg/seedling). The results showed that saline stress conditions caused by reduced osmotic potential affected ryegrass seed germination and vigor, as well as decreased the stature of the aerial and root parts of the seedlings. Out of the cultivars evaluated, La Estanzuela 284 was the most tolerant to saline stress. It is possible to cultivate ryegrass in areas with salinity up to mean values of -0.2 MPa osmotic potential. In this study, no significant decrease in seedling performance was observed.

Pages 985-989 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE1087
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Indirect estimation of leaf area in genotypes of 'Conilon' coffee (Coffea canephora Pierre ex A. Froehner)

Marcelo Curitiba Espindula*, Alexandre Martins Abdão dos Passos, Larissa Fatarelli Bento Araújo, Alaerto Luiz Marcolan, Fábio Luiz Partelli, André Rostand Ramalho

Empresa Brasileira de Pesquisa Agropecuária, Centro de Pesquisa Agroflorestal de Rondônia - Embrapa Rondônia, Brasil

Empresa Brasileira de Pesquisa Agropecuária – Embrapa Milho e Sorgo – Sete Lagoas, Minas Gerais, Brasil

Programa de Pós-Graduação em Ciências Ambientais, Campus de Rolim de Moura, Universidade Federal de Rondônia, Rondônia, Brasil
Departamento de Ciências Agrárias e Biológicas, Centro Universitário Norte do Espírito Santo, Universidade Federal do Espírito Santo, São Mateus – ES, Brasil


Abstract
Leaf area is an important parameter in agronomic and physiological studies; thereby, the techniques used for its determination should be simple, fast and accurate. The objective of this study was to evaluate the efficiency of an equation for the indirect determination of leaf area in 'Conilon' (Coffea canephora) genotypes cultivated in the Western Amazon. The experiment was carried out in Porto Velho, Rondônia, in August and September 2011. It was arranged in a completely randomized 2 × 15 factorial design combining two methods of determining leaf area (estimated and actual) and fifteen 'Conilon' coffee genotypes, with 64 replicates. The estimated leaf area was determined by the equation LA = 0.3064 × Age^(-0.0556)× LMR^(-2.0133) (R^2=0.98), developed by Partelli et al. (2006), while the actual leaf area was obtained from images of leaves scanned into digital format using an image scanner. The genotypes belong to the Coffee Breeding Program at Embrapa Rondônia. The efficiency of the equation for determining leaf area of 'Conilon' coffee varies according to the genotype evaluated; therefore, the equation must not be used without prior calibration. As the species is a perennial crop and the number of commercial genotypes widely accepted by farmers is restricted, the validation of the equation or the development of new equations capable of estimating the leaf area of the cultivated genotypes can help in the management of coffee plantationsn.

Pages 990-994 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE1090
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Different criteria for determining DRIS standards influencing the nutritional diagnosis and potential fertilization response of sugarcane

Leila Cruz da Silva Calheiros, Fernando José Freire*, Gilson Moura Filho, Emídio Cantídio Almeida de Oliveira, Adriano Barbosa Moura, José Valdemir Tenório da Costa, Flávio José Rodrigues Cruz, Águila Silva Santos

Center for Agrarian Sciences, Federal University of Alagoas, BR-104, Rio Largo, CEP 57100-00, Alagoas, Brazil
Agronomy Department, Federal Rural University of Pernambuco, street Dom Manoel de Medeiros, Dois Irmãos, Recife, CEP 52171-900, Pernambuco, Brazil
Coruripe Company, Triunfo Farmer, Rural Zone, CEP 57230-000, Alagoas, Brazil
Faculty of Agricultural and Veterinary Sciences, Department of Vegetable Production and Horticulture, São Paulo State University, stret Prof. Paulo Donato Castelane, CEP 14883-108, São Paulo, Brazil


Abstract
Integrated System of Diagnostic and Recommendation (DRIS) require establishment of norms for calculation of dual relationships between nutrients. Depending on the criteria used to establish the norms, nutritional diagnosis may vary. The objective of this study was to establish DRIS standards for sugarcane by different criteria and to evaluate the influence of these standards on the nutritional diagnoses. Four criteria were used: Nutrient relations with higher variance ratio between population of low and high productivity (C1); Nutrient relations with higher variance ratio and lower coefficient of asymmetry with partial transformation of Box and Cox (C2) and with total transformation of Box and Cox (C3); Nutrient relations with logarithmic neperian transformation (C4). The database consisted of 183 samples, in which 31 were in areas with high productivity (80 Mg ha-1) and 152 in areas with low productivity (<80 Mg ha-1). Sugarcane leaves in posicion (+3) were collected and contents of N, P, K, Ca, Mg, S, Fe, Zn, Cu, Mn and B were determined, according to the Kuijper system. The results implied that criteria for choosing nutritional relations with high ratios of variance for establishment of the DRIS norms were not adequate because the data were not standardized and presented a high probability of diagnosing nutritional imbalance. Criteria of the nutritional relations with high ratios of variance with a lowest asymmetry coefficient were more adequate because the data were normalized, providing similar nutritional diagnoses. Nutritional diagnoses were influenced by the criteria used to generate DRIS standards, diagnosing differences in positive response to fertilization.

Pages 995-1007 | Full Text PDF| Supplementary Data| doi: 10.21475/ajcs.18.12.06.PNE1147
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Influence of different sources of pollen on the chemical composition of date (Phoenix dactylifera L.) cultivar Medjool in México

Ricardo Salomón-Torres*, Noé Ortiz-Uribe*, Jesús A. Sol-Uribe, Carlos Villa-Angulo, Rafael Villa-Angulo, Benjamín Valdez-Salas, Conrado García-González, Cesar G. Iñiguez Monroy, Susana Norzagaray-Plasencia

Departamento de Posgrado, Universidad Estatal de Sonora, San Luis Rio Colorado, Sonora, México
Laboratorio de Bioinformatica y Biofotonica, Instituto de Ingeniería, Universidad Autónoma de Baja California, Mexicali, BC, México
Laboratorio de Materiales Avanzados, Instituto de Ingeniería, Universidad Autónoma de Baja California, Mexicali, BC, México
Laboratorio de Procesos Industriales, Instituto de Ingeniería, Universidad Autónoma de Baja California, Mexicali, BC, México
Facultad de Ingeniería, Universidad Autonoma de Baja California, Mexicali, BC, México


Abstract
The objective of the present work was to investigate the influence of pollen sources over chemical characteristics of the Medjool date cultivar. The study was conducted under conditions of the Northwest part of Mexico, during the year 2016 cultivation season. The content of nutrients (protein, lipids, fiber and ash), sugars (total, reducing, non-reducing, sucrose, glucose and fructose), and most abundant minerals were evaluated. Three bunches of each of the four selected female palms Medjool cultivar were pollinated with Deglet Noor, Khadrawy, Medjool and Zahidi cultivars, and their fruit were used for the analyses. Results show low concentrations of lipids and ash (0.68 - 0.80% and 2.49-2.82%, g/100 g dry weight basis), while protein and crude fiber were in the range of 2.92-3.35% and 6.86-7.29%, respectively. In addition, a high content of total sugars (77.78-70.04%) were found. The predominant mineral was potassium with a range of 794.30 (Khadrawy)-869.93 mg/100 g dry weight basis (Deglet Noor), followed by magnesium with 136.72 (Medjool) - 150.10 mg/100 g dry weight basis (Khadrawy). An analysis of total phenols revealed that the Khadrawy cultivar had the highest content, with 5.30 (mg GAE/100 g) and the lowest was for Zahidi with 3.82 (mg GAE/100 g). The Khadrawy cultivar had the highest effects on the chemical parameters of the four evaluated treatments. Therefore, pollen source has a significant effect on the chemical properties of the fruit from the Medjool cultivar.

Pages 1008-1015 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE1213
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Estimation of genetic parameters in white seed cowpea (Vigna unguiculata (L) Walp)

Hermes Araméndiz-Tatis*, Carlos Cardona-Ayala, Miguel Espitia-Camacho, Darlin Arrieta-Puche, Andrea Guerrero Barba

Universidad de Córdoba, Carrera 6N°76-103, Montería – Colombia. Grupo de Investigación Cultivos Tropicales de Clima Cálido, Colombia
Estudiantes de Ingeniería Agronómica, Colombia


Abstract
The objective of this research was to estimate genetic parameters of characteristics associated with yield in 42 genotypes of white colored cowpea. The experimental design was Federer’s augmented blocks, with five replications. Ten quantitative characters were recorded. Analysis of variance detected significant and highly significant differences between genotypes, in nine of the ten characters. The coefficients of phenotypic variation were greater than those of genotypic variation, due to the influence of the environment. High broad-sense heritability was revealed for peduncle length, 97.05%, number of pods per plant, 95.48% and weight of 100 seeds, 98.51%; the expected genetic progress varied between 0.07 (seed width) and 17.04 (seed yield per plant), while the genetic advance as a percentage of the average ranged from 2.80 (days to harvest) to 87.07 (seed yield per plant). The first four principal components explained 80.66% of the total variability; the length and width of the seed, and the weight of 100 seeds contributed to PC1; and the number of days, both for maturity of the first pod and for harvest, and the length of the pod, contributed to a greater degree to PC2. It was concluded that the number of pods per plant, the weight of 100 seeds and the yield of seed per plant are selection criteria for future breeding programs

Pages 1016-1022 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE1105
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Interactions among genes Sr2/Yr30, Lr34/Yr18/Sr57 and Lr68 confer enhanced adult plant resistance to rust diseases in common wheat (Triticum aestivum L.) line ‘Arula’

Mandeep S. Randhawa*, Caixia Lan, Bhoja R. Basnet, Sridhar Bhavani, Julio Huerta-Espino, Kerrie L. Forrest, Matthew J. Hayden, Ravi P. Singh

International Maize and Wheat Improvement Center (CIMMYT), Apdo, Postal 6-641, 06600 Mexico D.F., Mexico
International Maize and Wheat Improvement Center (CIMMYT), ICRAF house, United Nations Avenue, Gigiri, Village market-00621, Nairobi, Kenya
Campo Experimental Valle de México INIFAP, Apdo. Postal 10, 56230, Chapingo, Edo. de México, México
Department of Economic Development, Jobs, Transport and Resources, Agribio, 5 Ring Rd, Bundoora, Victoria 3083, Australia


Abstract
Common wheat line Arula displays an acceptable level of adult plant resistance (APR) to stripe rust (YR), leaf rust (LR) and stem rust (SR) in Mexico, and to SR (Ug99 races) in Kenya. Present study was conducted to identify genetic loci that confer resistance in Arula and to understand their interactions for rust resistance. A recombinant inbred line (RIL) population (190 lines) developed from the cross of Arula with susceptible parent Apav was phenotyped under artificially created epidemics of the three rusts in 2014, 2015 and 2016 in Mexico, and for stem rust (Ug99) during the off and main seasons of 2015 in Kenya. The RIL population and parents were genotyped with Sr2/Yr30-linked simple sequence repeat (SSR) marker gwm533 and two sequence tagged site (STS) markers (Lr34/Yr18/Sr57-csLV34 and Lr68-csGS) in addition to genotyping using Illumina iSelect 90K SNP array. A genetic map of 2,634 polymorphic markers (2,631 SNPs, 1 SSR and 2 STS markers) was constructed to locate the resistance loci. Composite interval mapping (CIM) was conducted to identify quantitative trait loci (QTL) associated with rust resistance using phenotypic and genotypic data in Windows QTL cartographer version 2.5. Two consistent QTL contributed by Arula were detected on chromosomes 3BS and 7DS, which corresponded to the previously known APR genes Sr2/Yr30 and Lr34/Yr18/Sr57, respectively. Sr2/Yr30 explained 1.1-14.7% and 41.0-61.5% of the phenotypic variation for YR and SR, respectively; whereas Lr34/Yr18/Sr57 accounted for 22.5-78.0%, 40.0-84.3% and 13.8-24.8% of the phenotypic variation for YR, LR and SR, respectively. Arula was also found to carry the positive allele for marker csGS closely linked to gene Lr68 on chromosome 7BL, although this gene was not detected using CIM. Based on presence or absence of identified genes/QTLs, lines were classified into different groups and t-tests were used to compare the mean relative area under disease progress curve (relAUDPC) over years of different gene combinations. RILs carrying both Lr34/Yr18/Sr57 and Lr68 showed significantly higher APR to LR showing the benefit of gene combination Lr34/Yr18/Sr57 + Lr68. Our results show that RILs possessing both Sr2/Yr30 and Lr34/Yr18/Sr57 had significantly enhanced APR to all three rusts in field trials conducted in Mexico and Kenya. Strategic utilization of these two pleiotropic, multi-pathogen resistance genes with other minor genes is recommended to develop durable rust resistant wheat cultivars.

Pages 1023-1033 | Full Text PDF| 10.21475/ajcs.18.12.06.PNE1305
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Evaluation of West Indian cherry (Malpighia emarginata) rootstock under saline water irrigation and nitrogen fertilization

Edinete Nunes de Melo, Reginaldo Gomes Nobre, Francisco Wesley Alves Pinheiro, Leandro de Pádua Souza, Geovani Soares de Lima*, Hans Raj Gheyi, Jutahy Jorge Elias, Wandra Laurentino da Silva

Federal University of Campina Grande, Academic Unit of Agricultural Science, Pombal, 58.840-000, Paraíba, Brazil
Federal University of Campina Grande, Academic Unit of Agricultural Engineering, Campina Grande, 58.109-970, Paraíba, Brazil
Federal University of Recôncavo of Bahia, Nucleus of Soil and Water Engineering, Cruz das Almas, 44.380-000, Bahia, Brazil


Abstract
This study aimed to evaluate the growth and quality of CMF 102 West Indian cherry rootstock subjected to irrigation with different salinity levels and nitrogen (N) doses. The experiment was carried out under protected environment, using a randomized block design in a 5 × 4 factorial scheme, with four replicates. Treatments consisted of five levels of electrical conductivity of water – ECw (0.3 – Control; 1.3; 2.3; 3.3 and 4.3 dS m-1) and four nitrogen doses (70, 100, 130 and 160% of N recommendation). CMI 102 West Indian cherry rootstock growth was evaluated through plant height, stem diameter, number of leaves, leaf area, shoot and total dry phytomass and Dickson quality index of seedlings 165 days after emergence. Additionally, the absolute growth rate of plant height was evaluated from 45 to 165 days after emergence. The results indicated that irrigation with ECw up to 2.22 dS m-1 leads to a maximum reduction of 10% in growth and in the quality of CMF 102 rootstock. Highest growth of CMF 102 West Indian cherry rootstock is obtained with fertilization of 70% of N. The plants of West Indian cherry irrigated with 4.3 dS m-1 of saline water showed an acceptable Dickson quality index; therefore, seedlings with IQD higher than 0.2 considered as good quality. In general, West Indian cherry plants can be classified as sensitive to irrigation with saline waters higher than 0.3 dSm-1. No significant effect was found for the interaction between water salinity and N doses.

Pages 1034-1040 | Full Text PDF| doi: 10.21475/ajcs.18.12.06.PNE1314



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