Production and morphophysiological responses of Panicum maximum cv. BRS Zuri to water availability
Edna. M. Bonfim-Silva*, Niclene. P. R. Oliveira, Horácio. M. Mazero, Daniele. J. Alves, Jakeline. R. Oliveira, Tonny. J. A. Silva
Institute of Agricultural and Technological Sciences, Federal University of Mato Grosso, Rondonópolis, MT 78735-901, Brazil
Abstract
Due to the increasing intensification of livestock farming and agricultural systems, there is demand for highly productive forage species. Panicum maximum cv. BRS Zuri is forage that has good productivity, vigor and promotes good animal performance. The objective of this study was to evaluate the morphophysiological and production characteristics of Panicum maximum cv. BRS Zuri subjected to water availability in Fluvic Neosol (Entisol). A potted-plant experiment was conducted in a greenhouse at the Federal University of Rondonópolis, Brazil. The experimental design was completely randomized, with five levels of water availability, corresponding to 25, 50, 75, 100 and 125 % of the maximum soil water holding capacity, and six replicates, in three successive cuts. The variables analyzed were: soil pH, SPAD index, plant height, leaf area, shoot dry mass, root dry mass, root volume, water consumption and water use efficiency. Water availability influenced the development of Panicum maximum cv. BRS Zuri, with the highest results between 67 % and 111 % of the maximum soil water holding capacity. The results show that the production and morphological responses were negatively influenced by water availability levels of 25 % and 125 %. These results makes it possible to affirm that, under the studied conditions, the cultivar BRS Zuri showed moderate adaptation to 125% water availability (excess water).
Pages 1203-1211 | Full Text PDF| doi: 10.21475/ajcs.22.16.11.p3703
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Management of the fertilization in Brazilian Savannas with phosphorus and potassium in the succession of soybean, millet and common bean with center-pivot system
Pedro Marques da Silveira, Adriano Stephan Nascente*, Luís Fernando Stone, Maria da Conceição Santana Carvalho
Brazilian Agricultural Research Corporation (EMBRAPA), Embrapa Arroz e Feijão, PO Box 179, 75375-000, Santo Antônio de Goiás, State of Goiás, Brazil
Abstract
In Brazilian Savannas (Cerrado), soil is managed in a sustainable way with built fertility and the demand for new fertilization will essentially involve the replacement of exported compounds through harvested products. The objective of this study is to improve criteria for fertilization with phosphorus and potassium in the soybean (summer)/millet (off-season)/irrigated common bean (winter) agricultural system. The study was carried out for three growing seasons under randomized blocks design with five treatments and five replications. The treatments consisted of T1= NPK common bean (recommended fertilization) + PK soybean (recommended fertilization); T2= NPK common bean (recommended fertilization) + soybean (without fertilization); T3= Common bean (without fertilization) + soybean PK (recommended fertilization); T4= NPK common bean (recommended fertilization) + P (amount exported by soybean) + soybean K (recommended fertilization); T5= NPK common bean (recommended fertilization) + P and K (amount exported by soybean) + soybean (without fertilization). The treatments T4 and T5 provided common bean and soybean yields (2945 and 4485 kg ha-1 and 2829 and 4412 kg ha-1, respectively) similar to the treatment T1 (2830 and 4353 kg ha-1), in which these crops received pre-fixed doses of recommended fertilization. It was necessary to make the fertilization only once in the year, and not in common bean and thereafter in soybean. We concluded that once there is no need to supply constant seeder with fertilizers for soybean, these treatments can be considered as fertilization management options in the soybean/millet/irrigated common bean agricultural system, which aims at greater operational profitability in planting activities.
Pages 1212-1216 | Full Text PDF| doi: 10.21475/ajcs.22.16.11.p3717
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Macro-and micronutrient content in native varieties of Phaseolus lunatus L. fertilized with rock dust
Tarciso B. Pereira Filho, Fillipe S. Marini, Marta S. M. Freitas, Emmanuel M. Pereira*
Federal University of Paraíba, Campus III, Department of Agriculture, CEP 58220-000, Bananeiras, PB, Brazil
Federal University of Paraíba, Campus I, Department of Geosciences, CEP 58050-085, João Pessoa, PB. Brazil
State University of the North Fluminense Darcy Ribeiro, Center for Agricultural Sciences and Technologies: Phytotechnics Laboratory – Plant Mineral Nutrition Sector, CEP 28613-602, Campos dos Goytacazes, RJ, Brazil
National Institute of the Semiarid, Campina Grande-PB, Brazil
Abstract
The objective of this study was to evaluate the macro- and micronutrient content in the leaves of Phaseolus lunatus L. fertilized with MB-4®. The research was carried out in two consecutive experiments, with a 2x5 randomized factorial block design and four replicates, in which two native varieties of Phaseolus lunatus L. were evaluated (Lima bean ‘Cara Larga’ and Lima bean ‘Branca’) based on responses to five varying doses of MB-4® (0, 100, 200, 400, and 800 g hole-1). Leaf analyses were performed to quantify nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, boron, copper, iron, manganese, and zinc. Leaf analysis indicated that N, P, K, Ca, Mg, Cu, Fe, Mn, and Zn levels increased significantly in the second year of cultivation, and that only B content decreased. The contents of N, P, Ca, B, Fe, Mn, and Zn were within the recommended range, whereas only K and Mg were outside the recommended range for the species. The values found between 200 and 400 g hole-1, corresponding to 4 and 8 t ha-1 of MB-4®, respectively, were the ones that contributed the most to the nutrient content increase in Lima bean varieties.
Pages 1217-1223 | Full Text PDF| doi: 10.21475/ajcs.22.16.11.p3728
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Closing yield gap of maize in Southeast Asia by intercropping systems: A review
Nuttapon Khongdee*, Krittiya Tongkoom, Kesinee Iamsaard, Nipon Mawan, Narit Yimyam, Wiriya Sanjunthong, Phitchayapha Khongdee, Suwimon Wicharuck
Department of Highland Agriculture and Natural Resources, Faculty of Agriculture, Chiang Mai University, Chiang Mai, 50200, Thailand
International College, Maejo University, Chiang Mai, 50290, Thailand
Department of Soil and Environmental Sciences, National Chung Hsing University, Taichung 402227, Taiwan
Department of Tropical Agriculture and International Cooperation, National Pingtung University of Science and Technology, Pingtung, Taiwan
Energy Technology for Environment Research Center, Faculty of Engineering, Chiang Mai University, Chiang Mai, 50200, Thailand
Abstract
Maize (Zea may L.) is a cereal crop grown extensively throughout Southeast Asia, particularly in Thailand, Indonesia, Vietnam, and the Philippines. However, maize yield in this region varies yearly due to several factors such as soil infertility, poor management practices, unpredictable weather conditions, and geography. This review aims (i) to demonstrate constraints and mitigation strategies for closing yield gaps and optimizing land use efficiency through the integration of companion crops into maize cropping, based on existing research in Southeast Asia between 1980 and 2021, and (ii) to discuss the benefits and drawbacks of growing maize alongside with other companion crops in Southeast Asia. Based on existing 50 articles of maize-based intercropping conducted in Southeast Asia founded from Google Scholar, Scopus and Web of science, cassava, legumes, potato, rice, grasses, and perennial crops such as rubber and coconut are the most frequently grown as companion crops in this region. Much emphasis of maize-based intercropping is paid to erosion control. Intercropping maize with other crops can successfully minimize soil erosion, runoff, and maintain the topsoil fertility. Therefore, less fertilizer input is required in intercropping system, which can also have a positive influence on the off-site environment. In addition, we discovered that maize-based intercropping improves the Land Equivalent Ratio (LER) (LER > 1) when planting time, crop spacing, and management practices are appropriately implemented. On the other hand, there are just a few studies that indicate the restrictions associated with maize-based intercropping (LER < 1). While it is theoretically beneficial to grow maize alongside with legumes due to biological nitrogen fixation, research undertaken in this region has not confirmed this statement when maize is intercropped with rice bean. Although, maize-based intercropping in Southeast Asia had been more thoroughly investigated in a variety of ways, further research is still needed to determine how maize-based intercropping mitigates the impact of climate change.
Pages 1224-1233 | Full Text PDF| doi: 10.21475/ajcs.22.16.11.p3733
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Rice demands higher nitrogen fertilizer during grain filling stage under elevated atmospheric CO2 condition
Md. Sohanur Rahman, Md. Abdullah Al Mamun*, Md. Main Uddin Miah, Md. Moynul Haque, Md. Mizanur Rahman, Md. Tanbir Rubayet, Jatish Chandra Biswas, Md. Abdul Karim, Md. Giashuddin Miah
Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
Krishi Gobeshona Foundation, Dhaka, Bangladesh
Abstract
An experiment was conducted in open top chamber (OTC) to determine the response of rice to elevated carbon dioxide (eCO2) under varying time of nitrogen (N) application. Rice was grown in OTC with 500 ppm CO2 (eCO2), 450 ppm CO2 (intermediate CO2, iCO2), ambient CO2 (aCO2) and open field (OF, 380 ppm CO2). The timings of N application were N1 = 1/3rd N at early tillering (ET) + 1/3rd at active tillering (AT) + 1/3rd before panicle initiation (PI) stage, N2 = 1/3rd N at ET + 1/3rd before PI + 1/3rd at booting stage (BS), and N3 = 1/3rd N at ET + 1/3rd before PI + 1/3rd at flowering stage (FS). The results revealed that photosynthesis (Pn), shoot and root dry matter (SDM and RDM) production, yield and yield components were favored at eCO2 when N application scheduled from ET to FS of rice. Interestingly, the N application up to FS of rice showed significant improved grain fertility and reduced sterility under rising CO2. However, rice plant accumulated and translocated more nutrients from shoot to grain under elevated CO2 (eCO2) condition. Moreover, higher grain amylose and lower protein was obvious at eCO2. Collectively, rice yield increased by 18 to 20 % under eCO2 with the application of N at FS of rice. These results indicate that to maximize rice yield under eCO2, it is crucial to supply N at FS of rice in order to increase grain fertility and reduce spikelet sterility.
Pages 1234-1242 | Full Text PDF| doi: 10.21475/ajcs.22.16.11.p3735
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Predicting teak tree (Tectona grandis Linn F.) height using generic models and artificial neural networks
Mariana Pacheco de Almeida, Eder Pereira Miguel, Mario Lima dos Santos, Ricardo Oliveira Gaspar, Cassio Rafael Costa dos Santos, Dione Dambrós Raddatz, Walmer Bruno Rocha Martins, Eraldo Aparecido Trondoli Matricardi
Federal University of Lavras, Department of Forest Engineering, Professor Edmir Sá Santos Square, W/N, 37200-000 Lavras, MG, Brazil
University of Brasilia, Department of Forest Engineering, University Campus Darcy Ribeiro W/N, 70910-900 Brasilia, DF, Brazil
Federal Rural University of Amazon, Capitão Poço Campus, Pau Amarelo Street, W/N,68650-000 Vila Nova, Capitão Poço, PA, Brazil
Abstract
The continuous monitoring of dendrometric variables provides estimates that assist in conducting fast-growing stands. In this study, we aimed to investigate the performance of generic models and artificial neural networks to estimate total height of Tectona grandis in a forest stand in the Eastern Amazon. Continuous forest inventory was performed in this population, where total height and diameter at breast height were measured. The variables such as age and the square root of the average diameter (dg) of the plots were used to compose the methods adopted to estimate the height of the trees. The accuracy of these methods was assessed using the residual standard error of the estimate, the coefficient of correlation, and the graphical analysis of residues. The aggregated difference and ANOVA were calculated to compare the methods. The independent variables mentioned were able to describe the height behavior of individuals. We concluded that the methods have good residual dispersion, normal distribution of errors and little tendency to overestimate height. It was found that the generic models and the ANNs do not differ significantly from each other and are efficient to estimate the height of individuals. We also concluded that the ANNs, especially those that included dg, presented superior statistical indicators.
Pages 1243-1252 | Full Text PDF| doi: 10.21475/ajcs.22.16.11.p3736
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The morphological and molecular variability of Sporisorium scitamineum isolates from Eswatini
Bongani Z. Nkhabindze*, Diana M. Earnshaw, Elijah M. Ateka, Harrison N. Wanyika
Department of Molecular Biology and Biotechnology, Pan African University Institute for Basic Science, Technology and Innovation (PAUISTI), Nairobi, Kenya
Department of Horticulture and Food Security, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
Crop Production Department, Faculty of Agriculture, University of Eswatini, Luyengo, Eswatini
Department of Chemistry, Jomo Kenyatta University of Agriculture and Technology, Nairobi, Kenya
Abstract
Sugarcane smut is a disease of economic importance in the sugarcane industry, occasioning losses of up to 50%. Current management practices have been ineffective in controlling the fungal disease, and hence the understanding of the pathogen and the development of appropriate control measures are required. This study investigates the morphology, virulence and molecular variability of Sporisorium scitamineum isolates from Eswatini to understand its pathogenicity for effective control. Fungal isolates were collected along the Sugarbelt in the Lowveld of Eswatini. The isolates were verified by polymerase chain reaction using the bE4 and bE8 specific primers with amplification of a 459bp fragment. The identity was further verified by DNA sequencing. The teliospores from the isolates were uniform in brown colour, spiny texture and circular shape. The teliospore sizes were significantly (P=0.05) different among the isolates. The isolate from Big-Bend had a mean spore diameter of 5.55µm, while Simunye, Nsoko and Mhlume had average diameters of 4.69µm, 4.98µm and 4.87µm, respectively. The documentation of the developmental stages revealed that the samples were of variable virulence with significantly (P=0.05) different rates of promycelium development. The variable virulence of the isolates was further confirmed by the in-vivo pathogen biomass quantification by RT-qPCR. Genetic distance matrix analysis and cluster analysis showed high homology (99-100%) among the local isolates which indicate that there is a low variability among the strains that are found in the selected sugarcane growing areas of Eswatini.
Pages 1253-1260 | Full Text PDF| doi: 10.21475/ajcs.22.16.11.p3769
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Cover crops and concentrations of carbon and nitrogen in Amazonian soil
Érica de Oliveira Araújo, Vitório Macieski Neto, Daniele Jesus Venturim, José Vanor Felini Catânio, Diogo de Souza Freitas, Jiovane Anderson da Silva Ribeiro
Department of Agriculture, Federal Institute of Education, Science and Technology, Rondonia State, Campus Colorado do Oeste, Brazil
Agronomic Engineering, Department of Agronomy, Federal Institute of Education, Science and Technology, Rondonia State, Campus Colorado do Oeste, Brazil
Animal Production, Department of Integration, Teaching, Research and Extension, Federal Institute of Education, Science and Technology, Rondonia State, Campus Colorado do Oeste, Brazil
Abstract
The present study aimed to evaluate the potential of dry matter production by cover crops and their effects on the dynamics of organic matter, organic carbon and nitrogen in the soil. This study contributes to minimize the effect of climate change and improve agricultural production systems. The experiment was conducted under field conditions, in the experimental area of the Federal Institute of Education, Science and Technology of Rondônia, Colorado do Oeste Campus, in the municipality of Colorado do Oeste, RO, Brazil. The experimental design was completely randomized, arranged in a factorial scheme, with four replications, consisting of six species of cover crops cultivated in pre-season (Crotalária ochroleuca, Crotalária spectabilis, Mucuna pruriens, Cajanus cajan, Canavalia ensiformis and Lablab purpureus) and four sampling depths (0-10 cm, 10-20 cm, 20-30 cm and 30-40 cm). The production and macronutrient contents in the dry mass of shoots of the different cover crops were evaluated, as well as the dynamics of organic matter, organic carbon and N in the soil at different sampling depths. The species Crotalaria ochroleuca and Crotalaria spectabilis showed great potential for dry matter production, while Lablab purpureus bean stands out in the extraction of nutrients such as P, K and Ca at full flowering. Lablab bean and Jack bean as cover crops were the most efficient strategies to promote the increase in the input of OM, C and N forms in the soil. NH4+-N and NO3--N contents were higher in the surface layers of the soil. Management with cover crops promoted gradual accumulation of SOM, which made it possible to influence the maintenance and increase of C and N concentrations in the soil and contributed to minimizing environmental impacts and increasing the quality and sustainability of soils and agricultural production systems.
Pages 1261-1269 | Full Text PDF| doi: 10.21475/ajcs.22.16.11.p3787