JANUARY 2024 | 18(01):2024 | 10.21475/ajcs.24.18.01
Characterization of selected cowpea and sesame accessions at Genetic Resources Research Institute (GeRRI) in Kenya: Adding value to the rich collection
Jane Muthoni*, Hussein Shimelis, Desterio O. Nyamongo
Kenya Agricultural and Livestock Research Organization (KALRO), Kenya
African Centre for Crop Improvement, University of KwaZulu-Natal, College of Agriculture, Engineering and Science, School of Agricultural, Earth and Environmental Sciences, Private Bag X01, Scottsxille 3209, Pietermaritzburg, South Africa
Abstract
Gene banking is the most cost-effective ex situ strategy for conserving plant genetic resources. It was developed for the storage of predominantly orthodox seeds. To maintain long-term seed survival and integrity of the conserved germplasm in the genebanks, seed viability testing and regeneration should be done occasionally. The seed viability tests inform which accessions need regeneration. In addition, adequate evaluation and characterization of the conserved germplasm enhances their wider utilization. The Genetic Resources Research Institute (GeRRI) in Kenya and Korea-Africa Food and Agriculture Cooperation Initiative (KAFACI) undertook a joint project entitled Improvement of Technology on Conservation of Genetic Resources from 2015 and 2018. Korea-Africa Food and Agriculture Cooperation Initiative was funding the project, while GeRRI was the implementing institution. One of the objectives was to carry out morphological characterization of sesame, millet and cowpea accessions conserved at GeRRI’s genebank to promote their conservation and utilization. A total of 376 accessions of two crops (216 cowpeas and 160 sesame) were withdrawn from the conservation unit at GeRRI’s genebank and characterized at KALRO’s Perkerra field site during the 2018 long rains season. About 78 % of the cowpea accessions had reached 50 % flowering within 60 days after planting. Over 80 % of sesame accessions yielded ≤ 400kg of seeds per hectare. Multivariate analyses were performed to establish similarity patterns. Principal Component Analysis (PCA) showed that four components had eigenvalues >1, accounting for 61.23 % of the total variability among the cowpea accessions. The first four PCs accounted for 63.95 % of the total variability for the sesame accessions. In addition, all the quantitative characters considered were important in describing phenotypic variation in these sesame accessions. The study has shown that there is wide variability among cowpea, as well as sesame accessions, conserved at GeRRI’s genebank. All the quantitative characters measured in this study were important in describing phenotypic variation among cowpea and sesame accessions.
Pages 1-10 | Full Text PDF| Supplementary Data PDF| doi: 10.21475/ajcs.24.18.01.p3997
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Forecast sugarcane maturity from agrometeorological data and soil water storage
Jordana Moura Caetano, Derblai Casaroli*, José Alves Júnior, Dayanna Teodoro Quirino, Adão Wagner Pêgo Evangelista, Frank Freire Capuchinho
Universidade de Brasília (UnB), Brasília, DF, Brazil
Universidade Federal de Goiás (UFG), Goiânia, GO, Brazil
Abstract
The environment (climate and soil) can stimulate the accumulation of sugars in the cane, inducing the plant´s maturation process. In this way, we can estimate sugarcane maturity based on the crop's growth response to environmental conditions, which allows us to quantify the raw material (ethanol or sugar) and plan the harvest. The aim of this study was to evaluate the effects of agrometeorological variables and soil water storage on the sugarcane maturation process and to generate forecasting models for soluble solids content (ºBrix) and total recoverable sugars (TRS, kg t-1). The experiment was carried out in the Santo Antonio de Goiás, Brazil. We evaluated °Brix and TRS of the sugarcane cycles (cane-plant, 1st ratoon, 2nd ratoon). The agrometeorological data was obtained from a weather station, which made it possible to calculate the crop’s water balance and degree-day. All the variables were subjected to multivariate statistical analysis, which selected the most significant variables. The models used degree-days, reference evapotranspiration and soil water storage as independent variables, which obtained multiple coefficients of determination (R_p^2) greater than 0.60. The estimates showed a good fit for both °Brix and TRS models, which determined a mean absolute error (MAE) of 1.15 ºBrix and 9.88 kg t-1, respectively; and very good confidence index (c > 0.75). Independent estimates obtained MAE < 2.60 ºBrix, while TRS resulted in MAE < 21.30 kg t 1, with “c” ranging from good to optimum (c > 0.70). Models based on multivariate analysis can be used to estimate the sugarcane harvest point based on the sugar content in the stalks, agrometeorological variables and soil water storage.
Received: 27/05/2023 | Revised: 04/10/2023 | Accepted:29/11/2023
Pages 11-20 | Full Text PDF| doi: 10.21475/ajcs.24.18.01.p4001
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Pre-emergence herbicides effects in no-till soybean system with Panicum maximum ‘BRS Tamani’
Mateus Matos da Silva, Edmilson Igor Bernardo Almeida*, Andreza Maciel de Sousa, Islana Silva Ponte, Bruna da Silva Brito Ribeiro, Daniel Lobo de Sousa, Andressa Carvalho de Sousa, Washington da Silva Sousa, Leonardo Bernardes Taverny de Oliveira, Jarlyson Brunno Costa Souza
Universidade Federal do Maranhão, 65.500-000, Chapadinha, Maranhão, Brazil
Universidade Federal Rural de Pernambuco, 52.171-900, Recife, Pernambuco, Brazil
Universidade Estadual Paulista Júlio Mesquita Filho, 14.884-900, Jaboticabal, São Paulo, Brazil
Abstract
The use of pre-emergence herbicides is an important strategy in resistant-weeds management, but its performance can be affected in no-till systems. This study aimed to analyse weed control from pre-emergence herbicides in no-till soybean system with Panicum maximum cv. BRS Tamani. The experiment was conducted in randomized block design with eight treatments and five repetitions. The treatments consisted in no-treatment, S-metolachlor + imazethapyr (1,200.00 g a.i. ha-1 + 100.00 g a.e. ha-1, respectively), S-metolachlor + fomesafen (1,035.66 g a.i. ha-1 + 227.70 g a.e. ha-1, respectively), S-metolachlor + diclosulam (1.200.00 g a.i. ha-1 + 29.40 g a.i. ha-1), imazethapyr + diclosulam (100.00 g a.e. ha-1 + 29.40 g a.i. ha-1), imazethapyr + flumioxazin (100.00 g a.e. ha-1 + 50.00 g a.i. ha-1), pyroxasulfone + flumioxazin (90.00 g a.i. ha-1 + 60.00 g a.i. ha-1) and pendimethalin (1,137.50 g a.i. ha-1). We evaluated weed phytosociological rates, weed control, and soybean growth. We identified 23 weed species distributed in 22 genera and 15 botanical families, majority of eudicotyledonous botanical class (78.2%), annual life cycle (56.5%), and sexual reproduction (100%). The integrated weed management, between herbicides and straw, was effective in herbicide-resistant weed control, except Euphorbia heterophylla. The treatments recommended included S-metolachlor combinations with fomesafen, imazethapyr, diclosulam, and also, pyroxasulfone + flumioxazin. The Panicum maximum cv. BRS Tamani straw was estimated in 11 t ha-1 and influenced negatively herbicides lipophilics and with slower movement, such as pendmethalin.
Received: 03/08/2023 | Revised: 22/09/2023 | Accepted:10/10/2023
Pages 21-28 | Full Text PDF| doi: 10.21475/ajcs.24.18.01.p4018
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Aerial survey and glyphosate-resistant weeds control before soybean seeding
Islana Silva Ponte*, Edmilson Igor Bernardo Almeida, Andreza Maciel de Sousa, Bruna da Silva Brito Ribeiro, Daniel Lobo de Sousa, Maria da Paz Pires Silva, Washington da Silva Sousa, Leonardo Bernardes Taverny de Oliveira, Bruno França da Trindade Lessa, Jarlyson Brunno Costa Souza
Universidade Federal Rural de Pernambuco, ZIP Code 52.171-900, Recife, Pernambuco, Brazil
Universidade Federal do Maranhão, 65.500-000, Chapadinha, Maranhão, Brazil
Universidade Federal do Vale de São Francisco, 56.300-990, Petrolina, Pernambuco, Brazil
Universidade Estadual Paulista Júlio Mesquita Filho, 14.884-900, Jaboticabal, São Paulo, Brazil
Abstract
Interference from herbicide-resistant weeds is one of the biggest impediments in soybean crops. The aim was to evaluate the spatial dynamics and weed control under glyphosate and glufosinate combinations before soybean seeding. The experiment was conducted in a striped arrangement with thirteen treatments and seven replicates. The treatments consisted in no-treatment, glyphosate, glyphosate + fomesafen, glyphosate + saflufenacil, glyphosate + diclosulam, glyphosate + imazetapir, glyphosate + flumioxazine, glyphosate + carfentrazone-ethyl, glyphosate + imazetapyr + flumioxazine, glyphosate + glufosinate, glyphosate + flumioxazine + carfentrazone, glufosinate + saflufenacil, glufosinate + flumioxazine. The weed spatial dynamic was analyzed for geostatistics methods, while weed control by conventional and UAV (Unmanned Aerial Vehicle) methods. We identified twenty weed species, representing eighteen different genera and fourteen botanical families. It's worth noting that eudicotyledonous species were the dominant group, primarily characterized by an annual life cycle and sexual reproduction. The utilization of precision agricultural methods proved highly effective in conducting weed surveys before soybean seeding. Using glyphosate alone is not recommended in fields with a history of reactive management with this herbicide. Alternatively, combining glyphosate and glufosinate with Protox-inhibitors showed outstanding control efficacy against glyphosate-resistant or glyphosate-tolerant weeds, Cenchrus echinatus, Spermacoce verticillata and Turnera subulata.
Received: 03/08/2023 | Revised: 12/09/2023 | Accepted:10/10/2023
Pages 29-36 | Full Text PDF| doi: 10.21475/ajcs.24.18.01.p4019
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Priming of Coffea arabica seeds improves the germination quality and stimulates antioxidant system enzymes
Giovana Janini Frota, Heloisa Oliveira dos Santos*, Giovani Virgílio Tirelli, Ana Luiza Reale, Sttela Dellyzete Veiga Franco da Rosa, Wilson Vicente Souza Pereira
Setor de Sementes, Universidade Federal de Lavras. Caixa Postal 3037, Campus Universitário. CEP 37200-900, Lavras, Minas Gerais, Brasil
Embrapa Café, Avenida W3 Norte (Final), Parque Estação Biológica, CEP 70770-901, Brasilia, DF
Abstract
Physiological conditioning is reported to result in faster and more uniform seedling emergence in the field and induces tolerance to environmental adversities. This study aimed to evaluate the efficiency of physiological conditioning on Coffea arabica L. seeds and drying rates through germination tests and enzymatic activity. C. arabica seeds from Catuaí Amarelo, with water contents of 43, 35 and 12%, were conditioned with distilled water, cathodic and anodic water, ascorbic acid, and sodium nitroprusside. The efficiency of the treatments was analyzed through tests of germination, emergence, electrical conductivity, and seedling growth. The activities of the enzymes superoxide dismutase, catalase, and ascorbate peroxidase were also measured. No priming agent was found to improve germination on seeds dried up to 12% water content, as little or no differences were found for those at 43%, while either ascorbic acid or sodium nitroprusside effectively improved vigor on 35% water content seeds. Our results indicate that sodium nitroprusside or ascorbic acid can be used as molecules to improve coffee seed vigor.
Received: 03/08/2023 | Revised: 24/08/2023 | Accepted:13/11/2023
Pages 37-44 | Full Text PDF| doi: 10.21475/ajcs.24.18.01.p4028
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Physiological potential of soybean seeds subjected to industrial treatment and storage time
Renata Cristiane Pereira, Alessandro Lucca Braccini, Breno Gabriel da Silva, Murilo Fuentes Pelloso, João Luiz Volpato Fracasso, Felipe dos Santos de Oliveira, Arthur Almenara Rosendo, Yana Miranda Borges
State University of Maringá, Maringá, Paraná, Brazil
University of São Paulo, São Paulo, Brazil
Federal Institute of Education, Science and Technology of Amazonas, Manaus, Amazonas, Brazil
Abstract
The use of treated seeds is a common practice among soybean producers, as it provides protection against pests and diseases existing in the soil, preventing their spread in exempt areas. Therefore, chemical treatment combined with different products becomes essential to guarantee success in the field.The objective of this study was to assess the influence that 7 industrial seed treatments (ISTs) and their respective slurry volumes have on the physiological potential of soybean seeds. The assay was carried out in a completely randomized design with 4 replications, with the treatments being arranged in a 7x6 factorial scheme (industrial treatments x storage periods). The chemical treatments were: control (untreated seeds) (ST1), fungicide + insecticide-1 + drying powder (ST2), fungicide + insecticide-1 + drying powder + micronutrient (ST3), fungicide + insecticide-1 + drying powder + micronutrient + biostimulant (ST4), fungicide + insecticide-1 + polymer + drying powder + insecticide-2 (ST5), fungicide + insecticide-1 + polymer + drying powder + insecticide-2 + micronutrient (ST6), fungicide + insecticide-1 + polymer + drying powder + insecticide-2 + micronutrient + biostimulant (ST7). For each IST, the specific slurry volume was 0, 350, 550, 1050, 500, 700 and 1200 mL 100 kg-1 of seeds, respectively. The seeds were stored for periods of 0, 15, 30, 45, 60 and 90 days and subsequently checked for their physiological potential. In each storage period, the following tests were conducted: germination, first count, accelerated aging, emergence speed index, and final emergence in sand substrate. Among the evaluated treatments, ST4 and ST7 were the most harmful to the physiological quality of the seeds in all storage periods, since they presented the greatest slurry volume. In relation to treatments with less harmful effects on seeds, treatments ST2 and ST3 presented higher averages for most of the variables analyzed.
Received: 24/08/2023 | Revised: 27/10/2023 | Accepted: 29/11/2023
Pages 45-49 | Full Text PDF| Full Text PDF| doi: 10.21475/ajcs.24.18.01.p4048
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Effects of black sun shade nets and humidity levels on cassava growth for mini-cutting propagation
Nguyen Van Minh, Nguyen Van Loc
Faculty of Agriculture and Forestry, Tay Nguyen University, Dak Lak, 63100, Vietnam
Faculty of Agronomy, Vietnam National University of Agriculture, Hanoi, 131000
Abstracts
This research presents the effects of black sun shade nets and humidity levels on cassava growth for mini-cutting propagation. The experiments were split-plots design with three replicates where two net shade covering treatments: one with 100% coverage using black sun shade net and the other with no covering as control were assigned in main plots and three humidity levels: 65-70%, 70-75%, and 75-80% to sub-plots. Data on shoot emergence rate, numbers of shoots per stem cutting, plant height, number of leaves and shoot diameter were measured. The obtained results suggested that the combination of 50% covering with black sun shade nets and maintaining a humidity level of 70-75% is effective for cassava multiplication Our findings may help in further strategy for the application in cassava rapid propagation.
Received: 21/09/2023 | Revised: 25/10/2023 | Accepted: 13/11/2023
Pages 50-54 | Full Text PDF| doi: 10.21475/ajcs.24.18.01.p4094