Australian Journal of Crop Science   AJCS

JULY 2022 | 16(07):2022 | EARLY VIEW | 10.21475/ajcs.22.16.07


Optimization of water use in Coffea arabica L. grown under different agronomic practices

Dalyse Toledo Castanheira, Rubens José Guimarães, Tiago Teruel Rezende, Milene Alves de Figueiredo Carvalho, Caroline Abreu Knuppel, Raphael Comanducci da Silva Carvalho

Universidade Federal de Lavras / UFLA, Departamento de Agricultura / DAG, CP 3037, Lavras, MG, 37200-900 Brazil
Universidade José do Rosário Vellano, Instituto de Ciências Agrarias, Escola de Agronomia, Rodovia MG-179, Alfenas, MG, 37130-000 Brazil
Empresa Brasileira de Pesquisa Agropecuária / Embrapa Café, Parque Estação Biológica, Av. W3 Norte, CP 40315, Brasília, DF, 70770-901 Brazil


Abstract
Lower water availability due to climate change has dramatically affected coffee yields and quality. Characteristics related to plants and soil can be explored to obtain more productive and sustainable coffee production under adverse crop conditions. To this end, the objective of this study was to evaluate the potential for using different agronomic practices to optimize water use in coffee plants and to mitigate the effects of lower water availability to the crop. In the plots, three soil management systems (polyethylene film, brachiaria and bare soil) were used. In the subplots, two types of fertilizers were used (conventional and controlled-release fertilizer). Five soil conditioners (coffee husk, gypsum, water-retaining polymer, organic compost, and the control) were distributed throughout the sub-subplots. The plant growth, soil moisture, leaf physiology and anatomy, and soil chemical properties of coffee plants were analysed. The management of the soil cover using polyethylene film or brachiaria stood out as agronomic practices that can be combined with coffee husk applications to enable the better use of water by coffee plants and to favour soil conditioning. Controlled-release fertilizer and gypsum allowed for improvements in the anatomical and physiological characteristics of the plants. The use of organic compost favoured greater water availability; however, it caused losses in terms of coffee growth and physiological parameters due to nutritional imbalance. Therefore, based on results, the use of polyethylene film, brachiaria, controlled-release fertilizer, coffee husks, and gypsum are potential agronomic practices for optimizing water use and mitigating the effects of water deficit in coffee plants.

Pages 870-878 | Full Text PDF| doi: 10.21475/ajcs.22.16.07.p2355
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Soil physical attributes in an integrated crop-livestock system with pasture managed under different sward canopy heights and different timings of nitrogen application

Wilson Henrique Tatto*, André Brugnara Soares, Tangriani Simioni Assmann, José Ricardo da Rocha Campos, Regis Luis Missio, Pablo Antônio Beltran Barriga

Universidade Tecnológica Federal do Paraná, Brazil

Abstract
This study aimed to evaluate the physical attributes of soil in an integrated crop-livestock system with winter pastures managed under different N fertilization timings and canopy heights after winter and the soybean crop. The experimental design used was randomized blocks with the treatments in a 2 × 2 factorial arrangement (two canopy heights and two N application timings), with three area replications. The canopy heights were 11 and 24 cm kept by continuous stocking grazing method since May to November (175 days). Fertilization timings as N-pasture fertilization and N-corn fertilization (phase before the winter pasture). Treatments characterized as N fertilization inversion were applied with fertilization timings as N-pasture fertilization and N-corn fertilization (phase before the winter pasture). Soil density, total porosity, and moisture content were evaluated after winter pasture (black oat + annual ryegrass) and after the subsequent summer soybean crop. The sampling spots were georeferenced and analyzed using geostatistics, considering the position in the slope of landscape. Soil physical attributes were not influenced by canopy height nor N fertilization timing (P>0.05). Soil density was reduced by 13.3% (from 1.11 to 0.98 g cm-3), whereas total porosity (from 0.58 to 0.62%) and moisture content (from 32.73 to 35.73%) increased by 6.9% and 9.2% after the soybean crop in relation to the values obtained in the winter pasture. The higher elevation areas had higher moisture content, total porosity, and lower density than the lower elevation areas, regardless of the time of evaluation. Well-drained soils were more resistant to compaction by animal trampling than moderately drained soils. In well-managed integrated crop-livestock systems in humid subtropical climate regions, the surface compaction of clayey soils in winter pastures is light, non-limiting, and disappears after the subsequent summer crop.

Pages 879-885 | Full Text PDF| doi: 10.21475/ajcs.22.16.07.p3226
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Evaluating the adaptability and stability of common peanut varieties (Arachis hypogaea L.) in Northern Mozambique using the AMMI Bayesian model

Joel Jorge Nuvunga, Cristian Tiago Erazo Mendes*, Alessandra Querino da Silva, Luciano Antonio de Oliveira, Carlos Pereira da Silva, Lídia Andarusse, Júlio Sílvio de Sousa Bueno Filho

Chibuto College of Business and Entrepreneurship, Eduardo Mondlane University, Chibuto, Gaza, Mozambique
Department of Statistics, Federal University of Lavras, Lavras, Minas Gerais, Brazil
Faculty of Exact Sciences and Technology, Federal University of Grande Dourados, Mato Grosso do Sul, Brazil
Instituto de Investigação Agrária de Moçambique, Nampula-Moçambique


Abstract
This study evaluated the stability and adaptability of common peanut cultivars (Arachis hypogaea L.) in three locations across northern Mozambique over four years, using the additive main effects and multiplicative interaction model (AMMI) under a Bayesian approach. The multi-environmental data consisted of 20 genotypes evaluated in three locations. We analyzed grain yield in tons per hectare in a complete randomized block design for each location. The results indicated that genotypes with higher marginal yield contribute to the genotype by environment interaction (GEI) and thus are not largely recommended for the entire target environment. The Namapa (NMP) location showed consistent behavior and did not contribute to the GEI effect, and in this sense, G6 and G7 would be the best indications for this location. Moreover, genotypes considered stable, with emphasis on the G20 genotype, did not have a good average yield. Mapupulo (MPPL) and Nampula (NLP) had a significant contribution to GEI, and the best genotypes for these locations were G7 and G3, respectively. In this sense, the results of the analysis specified that using genotypes in specific environments would be the best strategy to decrease the effect of GEI and increase peanut productivity in the environments considered.

Pages 886-892 | Full Text PDF| doi: 10.21475/ajcs.22.16.07.p3442
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Phosphorus fertilizer with increased efficiency affects soybean yields

Carlos Henrique Eiterer de Souza, Victor Gustavo Soares Ribeiro, Lara Lúcia Gonçalves, Mateus Gonçalves de Borba, Roberto dos Anjos Reis Jr

University Center of Patos de Minas, Patos de Minas, MG, Brazil
Federal University of Viçosa, Viçosa, MG, Brazil
University Center of Patos de Minas, Patos de Minas, MG, Brazil
University Center of Patos de Minas, Patos de Minas, MG, Brazil
Wirstchat Polímeros do Brasil, Londrina, PR, Brazil


Abstract
Phosphate fertilization is an important tool for achieving high yields in soybean, especially in tropical soils where phosphate fertilization efficiency is low. Fertilizers with improved efficiency, such as polymer-coated fertilizers, are one of several strategies to increase P fertilization efficiency. The objective of this study was to evaluate plant growth, leaf P content, soybean yield, and P fertilization efficiency in different seasons in response to P rates and sources. A factorial experiment (2 x 4) + 1 using two P sources (monoammonium phosphate (MAP) and Policote-coated MAP), four P rates (40, 80, 120, and 160 kg P2O5 ha-1), and the control (no P fertilization) was conducted with soybean in the 2016-2020 seasons. Phosphate fertilization increased soybean yield and was affected by P rates and sources. Soybean yield increased from 1464.7 kg ha-1, 468.4 kg ha-1, and 2297.3 kg ha-1 without P fertilization to 3,638.5 kg ha-1, 3,682.1 kg ha-1, and 3,856.7 kg ha-1, respectively, when MAP was applied at 158.0, 125.3, and 160 kg ha-1 P2O5, while when Policote coated MAP, the maximum productivity was 3,950.3 kg ha-1, 4,380.5 kg ha-1 and 4,343.0 kg ha-1 with 159.0, 160.0 and 140.1 kg ha-1 P2O5, respectively, in 2017/2018, 2018/2019 and 2019/2020 seasons. Increasing phosphate fertilizer rates decreased agronomic P use efficiency (APUE), which was mitigated by P-coated fertilizer (fertilizer with improved efficiency). Lower APUE was observed in the 2019/2020 season, likely as a result of residual effects from previous phosphate fertilizer applications.

Pages 893-898 | Full Text PDF| doi: 10.21475/ajcs.22.16.07.p3538
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Spatial relation of weed competition and soil fertility in soybean farming

José Augusto Lima Furtado, Edmilson Igor Bernardo Almeida*, Leonardo Bernardes Taverny de Oliveira, Antonio Clementino dos Santos, Tiago Vieira da Costa, Marcelo de Sousa da Silva, Jarlyson Bruno Costa Souza, Washington da Silva Sousa, Islana Silva Ponte, José Roberto Brito Freitas

Universidade Federal do Maranhão, CEP 65.500-000, Chapadinha-MA, Brazil
Universidade Federal do Tocantins, CEP 77.804-970, Araguaína-TO, Brazil
Universidade Estadual Paulista Júlio Mesquita Filho, CEP 14.884-900, Jaboticabal-SP, Brazil


Abstract
Soybean is one of the main crops in Brazil, with a significant share of national agribusiness exports. Nonetheless, several factors such as weed competition and soil fertility directly affect soybean yield and productivity. This study aimed to analyse the spatial distribution of weeds as a function of soil fertility and soybean yield in farming fields. We carried out the experiment on a farm located in Brejo, Maranhão state, Brazil, through a geostatistical analysis of 60 sampling points on a regular grid of 10.0 m x 50.0 m. At these points, we collected phytosociological information on the weed community, soil fertility, and soybean yield. We performed principal component analysis (PCA) to determine the most responsive variables and to group them. We determined spatial dependence through geostatistical procedures, with the interpretation and adjustment of variogram components. We identified seven weed species, distributed across seven genera and six botanical families, of which 76.78% were eudicotyledons. In the cluster analysis, we grouped monocotyledonous species separately from eudicotyledons as explained by the morphophysiological contrasts between these botanical classes. Soybean yield did not correlate with soil fertility or weeds. These two factors can be considered only as a share of soybean productivity because their individual variations do not directly influence production factors. The efficient management of weeds and soil fertility should result in a more uniform and potencially more soybean yield when other conditioning factors are also effective.

Pages 899-906 | Full Text PDF| doi: 10.21475/ajcs.22.16.07.p3548
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Production and availability of good quality seed potatoes in the East African region: A review

Jane Muthoni, Hussein Shimelis, Jacob Mashilo

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
Limpopo Department of Agriculture and Rural Development, Towoomba Research Station, Crop Research Division, Private Bag X1615, Bela-Bela, South Africa


Abstract
Demand for potatoes has grown rapidly in eastern Africa due to rapid population growth, urbanisation and life style changes. This has made potato an important commodity crop in the region contributing to food security and enhanced livelihoods. However, potato productivity in the region is low; ranging from 6 to10 t/ha against potential yields of over 30 t/ha. One of the major causes of low yields is the chronic shortage of good quality seed potatoes for planting, which also limits adoption of new and improved varieties. Therefore, the objective of this paper is to highlight the opportunities and progresses in the production and availability of good quality seed potatoes in the East African region to bolster the productivity and commercial value of the crop. The first section of the paper discusses the status of good quality seed potatoes production and availability in the East African region. The second section looks at the farmer-based seed potato production technologies while the third section focuses on the efforts of both the private and public sector in production of good quality seed potatoes. Availability of good quality seed potatoes constitutes < 1% of the requirement in eastern Africa. These seeds are mainly produced by public research institutions as well as some private players. Consequently, most farmers opt to plant seed potatoes from informal sources. However, seeds from informal sources are mostly of poor quality and often accelerate the spread of tuber-borne diseases, especially viruses and bacterial wilt. To improve seeds from informal system, some technologies have been identified and promoted to enhance farmer-based seed production and distribution. These include seed plot technology (SPT), positive selection techniques (PST) and Quality Declared Seed (QDS) systems. In addition, there has been adoption and promotion of rapid multiplication techniques (RMT) such as stem/shoot cuttings, aeroponics, sandponics, and hydroponics among others. Other measures that have been taken include importing seeds of new potato varieties. The imports increase the quantity of seeds and the number of potato varieties available to farmers. Despite these efforts, the quantity of good quality seeds available is still far below the requirements. There is need for the governments, private sector players as well as farmers to enhance their efforts and save the situation. Governments need to invest seriously in local breeding activities and multiplication of early generation seeds. These and other measures may increase availability of good quality and affordable seed potatoes in East African region.

Pages 907-915 | Full Text PDF| doi: 10.21475/ajcs.22.16.07.p3566
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Comparison between Matheron and Genton semivariance function estimators in spatial modeling of soybean yield

Gustavo Henrique Dalposso*, Miguel Angel Uribe-Opazo, Marcio Paulo de Oliveira

Federal University of Technology – Paraná (UTFPR), Toledo, Paraná, Brazil
Western Paraná State University – (UNIOESTE), Cascavel, Paraná, Brazil


Abstract
In precision agriculture, interpolations are performed to map soybean yield, which facilitates decision making. Among the existing methods, geostatistics prevails, which uses information from the data’s spatial structure to generate interpolated maps. The spatial dependence structure is modeled based on the semivariogram, with the Matheron semivariance estimator being the most commonly used function. However, studies show unreliability in the presence of outliers; therefore, other researchers propose an alternative use of the Genton semivariance function estimator. Despite several studies comprising comparative works involving both estimators of the semivariance function, there are only a few comparative studies considering theoretical semivariograms with cyclical behavior, such as the Wave model. This study, therefore, aims to compare these two estimators considering adjustments of the Wave model in soybean yield data, when containing an outlier. The spatial dependence measure index was used to measure the degree of the model’s spatial dependence and the weighted Kappa index to assess the similarity of maps generated through kriging. It was possible to verify that the outlier removal was more impactful in the modeling considering the Matheron semivariance function estimator, thus confirming the robustness of the Genton semivariance function estimator.

Pages 916-921 | Full Text PDF| doi: 10.21475/ajcs.22.16.07.p3568
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Intercrops of grass with legumes as green manure for agroecological systems

Guilherme Alexandre Pacheco Gut, João Virgínio Emerenciano Neto, Rodrigo da Silva Santos, Roseli Freire de Melo, Daniel Maia Nogueira, Gelson dos Santos Difante, Antonio Leandro Chaves Gurgel*, Ítalo Luís Oliveira Santana

Campus of Agricultural Science, Federal University of Vale do São Francisco, Petrolina, PE, Brazil
Academic Unit Specializing in Agricultural Science, Federal University of Rio Grande do Norte, Macaíba, RN, Brazil
Brazilian Agricultural Research Corporation, Petrolina, PE, Brazil
Faculty of Veterinary Medicine and Animal Science, Federal University of Mato Grosso do Sul, Campo Grande, MS, Brazil
University of de Pernambuco, Petrolina, PE, Brazil


Abstract
The stud article aimed to assess the accumulation and rates of nutrients in the biomass of the consortium of millet and leguminous plants for green fertilisation. The treatments were consortia of millet with four different leguminous plants: Cajanus cajan, Canavalia ensiformis, Mucuna aterrima, and Dolichos lablab. The treatments were distributed in a completely randomised design with four replications. The species of each consortium were planted in a line, at a distance of one metre apart. The aerial part of the plants was harvested after 90 days to determine the botanical composition, intercropping biomass, and the amount and accumulation of macronutrients in the biomass. The Millet mass did not differ among the consortia. However, among the legumes, M. aterrima has the highest mass (2806.31 kg/ha DM), which is reflected in the lower ratio of leguminous grasses in the millet consortium with M. aterrima (4.61). The consortia affected the rate and accumulation of P, B, and Fe. The biomass of the millet consortium with C. cajan presented the lowest rate. In addition, the accumulation of K, Mg, and Zn was low in this consortium. The biomass of millet intercrops with M. aterrima, D. lablab and C. ensiformis showed higher accumulations of K, Ca, and Mg. The highest accumulation of N was observed in the biomass of the consortium with M. aterrima (50.71 kg/ha). The rates and accumulations of Cu and Zn were higher in the consortium with M. aterrima. The consortium of millet with the leguminous plants is a sustainable alternative for fertilisation. The consortia with M. aterrima and D. lablab are the most promising ones, due to the higher proportion of plants.

Pages 922-927 | Full Text PDF| doi: 10.21475/ajcs.22.16.07.p3597
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Similarity networks in genotypes of Vigna unguiculata (L.) Walp for green-grain production

Angela Maria dos Santos Pessoa*, Cândida Hermínia Campos de Magalhães Bertini, Emanuel Magalhães da Costa, Tomil Ricardo Maia de Sousa, Anderson Rodrigo da Silva, Ana Kelly Firmino da Sillva

Federal University of Ceará, Fortaleza/CE, Brazil
Instituto Federal Goiano, Urutaí, Goiás, Brazil


Abstract
Cowpea is one of the most significant food and nutrient sources worldwide, with importance in three primary market sectors: dry grains, seeds, and the expanding green-grain sector. This study aimed to identify phenotypic patterns for selection in Vigna unguiculata (L.) Walp genotypes for green-grain production using similarity networks and identify its morpho-agronomic variables with greater discrimination ability. The rainfed experiment was conducted in the experimental area of the horticultural sector at the Plant Science Department of the Agricultural Sciences Center of the Federal University of Ceará, Brazil, with 42 treatments. Three seeds were sown per hole, and the plants were thinned to two plants per hole, 15 days after sowing. Characterization was performed based on quantitative and qualitative variables, and the data were subjected to multivariate analysis of variance based on an augmented block design. The conjugate distance matrix for the variables was graphically represented using similarity networks to identify phenotypic patterns. The results indicated that genotypes CE-164, 207, 999, 994, 1002, and 1007 should not be used in breeding programs for green-pod production since they show genetic similarity within commercial cultivars. The variables of days to fruiting, green-pod length, green-pod width, green-pod thickness, and green-grain thickness contribute to genetic divergence and have high heritability values. Crosses between cowpea genotypes CE-165, 244, 22, 96, and 98 can yield gains in green-grain production in advanced generations.

Pages 928-932 | Full Text PDF| doi:10.21475/ajcs.22.16.07.p3599
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Productive characteristics and economic analysis of tropical forage grasses cultivated under different sowing methods in intercropping production systems

Rosane Cláudia Rodrigues, Clésio dos Santos Costa, Maciel Costa Teixeira, Bruno Eduardo de Caxias Miranda, Izakiel Reis Marinho, Eduarda Castro da Silva, Kátia Aparecida de Pinho Costa, Yara Lima de Souza, Dhiéssica Morgana Alves Barros, Ivo Guilherme Ribeiro de Araújo, Ana Paula Ribeiro de Jesus, Michel Oliveira Rocha, Pedro Lucas Oliveira Rocha

Department of Animal Science, Federal University of Maranhão, Chapadinha, MA, Brazil
Federal Institute of Education, Science and Technology Goiano - Campus Rio Verde, Brazil


Abstract
This study aimed to evaluate sowing methods of different tropical grasses in integrated production systems on morphogenic and structural characteristics, chemical composition, and corn yield. The experiment was carried out in a completely randomized design, with a 3 x 3 + 1 factorial arrangement, with three forages: andropogon grass (Andropogon gayanus Kunth cv. Planaltina), massai grass (Megathyrsus maximum cv. Massai) and ruziziensis grass (Urochloa ruziziensis), three ways of sowing intercropped with corn (one row, two rows and broadcast) with four replications and corn in monoculture. Soil preparation, corrective practices and monitoring were carried out as recommended by the species. The results revealed that the sowing methods did not interfere with the interaction for morphogenic and structural characteristics of the grasses. Leaf elongation rate (LER) did not differ among grasses and sowing forms for Andropogon, Massai, and Ruziziensis grasses. There was an interaction effect (P<0.05) for leaf production (LP); the massai grass exhibited higher production compared to other grasses. The spread sowing method produced less leaf availability for the massai grass. There was no effect (P>0.05) of interaction for the variables of the chemical composition of grasses. Maize production was not altered due to the different consortia; however, a much lower value was found when producing corn in monoculture. The average production of intercropped corn was 3420 kg and ha-1, against 1680 kg of single cultivated corn. Massai grass and Ruziziensis grass is an attractive alternative for intercropping with corn in integrated systems.

Pages 933-940 | Full Text PDF| 10.21475/ajcs.22.16.07.p3603
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The density and sowing time of buckwheat in organic and conventional growing system

Juliana Aozane da Rosa, José Antonio Gonzalez da Silva, Raul Vicenzi, Ana Paula Cecatto, Angélica Reolon Costa, Cibele Luisa Peter, Natiane Carolina Ferrari Basso, Ivan Ricardo Carvalho, Francine Lautenchleger, Jaqueline Sgarbossa, Denize da Rosa Fraga, Willyan Júnior Adorian Bandeira

Regional University of the Northwest of Rio Grande do Sul, Ijuí, Brazil. Street of Comércio 3000, Universitário, Ijuí/RS, Brazil
Educational Society Três de Maio (Setrem), Avenue Santa Rosa, 2405, Center, Três de Maio/RS, Brazil
State University of Central-West - Street Presidente Zacarias, 875, Guarapuava/PR, Brazil
Federal University of Santa Maria (UFSM), Avenue Roraima, 1000, City Universitária, Camobi, Santa Maria/RS, Brazil


Abstract
The adjustment of buckwheat density and sowing time in an organic growing system guarantees satisfactory productivity with better environmental quality. The objective of the study is to adjust the sowing density and the best growing season of buckwheat, comparing the organic and conventional growing system. In the study, two experiments were conducted in 2017 and 2018. Experiment one, in a randomized block design with eight replications in a 4 x 2 factorial, for sowing density (40, 80, 120 and 160 kg ha-1) and growing location (Augusto Pestana and Três de Maio, RS, Brazil), respectively. Experiment two, in a randomized block design in a 2 x 2 factorial with eight replications, for sowing time (September and December) and growing system (conventional and organic), respectively, carried out in Augusto Pestana, RS. Grain yield and other characters of agronomic interest of the species were evaluated, with means analysis and regression adjustment. The sowing density around 110 kg ha-1 brings benefits in the buckwheat growing in reaching maximum grain yield in conventional and organic systems. Sowing in September and December is possible regardless of the production system, however, grain yield is maximized under the milder temperature conditions of September. The grain yield in an organic system, although statistically inferior to the conventional one, proves to be advantageous due to the reduced variation in yield due to add value of the product without the use of pesticides and fertilizers.

Pages 941-948 | Full Text PDF| doi: 10.21475/ajcs.22.16.07.p3604
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Photosynthetic light response curves in Eucalyptus benthamii and Eucalyptus dunnii clones

Marcio Carlos Navroski*, Mariane de Oliveira Pereira, Enéas Ricardo Konzen, Letícia Miranda, Regiane Abjaud Estopa, Clenilso Sehnen Mota

Departamento de Engenharia Florestal, Universidade do Estado de Santa Catarina, Lages, Santa Catarina, Brazil
Universidade Federal do Rio Grande do Sul, Estudos Costeiros Limnologicos e Marinhos. Imbé, RS. Brazil
Klabin Florestal, Telêmaco Borba, PR, Brazil
Instituto Federal Catarinense, Campus Rio do Sul. Rio do Sul, SC, Brazil


Abstract
The photosynthetic light-response curve reflects the instantaneous response of the net photosynthetic rate to different gradients of photosynthetically active radiation. Genetic materials can respond differently to light and consequently alter productivity. Thus, this work aimed to compare clones of Eucalyptus benthamii and Eucalyptus dunnii by checking the CO2 assimilation rate due to the increase in photosynthetically active radiation. The evaluations were carried out in mini-stumps implanted in a clonal mini-garden system. The CO2 assimilation rate curves were determined with the aid of a portable photosynthesis meter. The curves of CO2 assimilation rate (A) in response to the increase in photosynthetically active radiation (PAR) were evaluated at values of 1500, 1000, 700, 450, 250, 120, 50 and 0 μmol m-2 s-1 for clones of E. benthamii and E. dunnii. The three Eucalyptus clones evaluated showed a similar behavior of the A/PAR curve, showing a high demand for photosynthetically active radiation. In general, the three clones were very similar in terms of CO2 assimilation rate due to the increase in photosynthetically active radiation.

Pages 949-954 | Full Text PDF| doi: 10.21475/ajcs.22.16.07.p3625
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Analysis of optimum age and maximum increment of forest stands for developing community forests

Imran Rachman*, Indrianto Kadeko, Andi sahri Alam, Adam Malik, Effendy

Forestry Studies Program, Forestry Faculty of Tadulako University, Palu, 94118, Indonesia
Department of Agriculture, Agriculture Faculty of Tadulako University, Palu 94118, Indonesia
Department of Agriculture Economics, Agriculture Faculty of Tadulako University, Palu 94118, Indonesia

Abstract
The community forests are one of the main suppliers of wood needs in the future. They require careful attention to the wood type to be planted, preferably choosing plants that have a short cycle. The demand for wood for the community is increasing, while the supply of timber from state forests to the wood processing industry is decreasing. This research aimed to analyze the optimum age and maximum increment of community forest stands and which species were more profitable. This research was done in a community forest with tropical environmental type. This research was quantitative, calculating the maximum volume cycle and Mean Annual Increment (MAI) values in community forest stands. The results show that the maximum volume increment was found in jabon (Anthocepalus sp) stands, namely at the age of 8 years, with a total of 600 trees/ha, an average diameter of 30 cm, an average height of 13 m, a total volume of 330.64 m3/ha, and a mean annual increment (MAI) of 41.33 m3/ha/year. Jabon stands at the age of 8 years were suitable for harvest because they reached the maximum volume increment in the soil types of Hapludults Dystrudepts, Haplustepts Haplustalfs, and Endoaquepts Udifluvents.

Pages 955-963 | Full Text PDF| doi:10.21475/ajcs.22.16.07.p3639
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Zinc and methyl jasmonate modulate the growth and the volatile compounds of the 'Albahaca Dante' basil cultivated in vitro

Felipe Gomes Claudino, Natalia Caroline Anastacio Souza, Felipe Górski, José Eduardo Gonçalves, Zilda Cristiani Gazim, Hélida Mara Magalhães

Postgraduate Programs in Biotechnology Applied to Agriculture, Paranaense University, Mascarenhas de Moraes Square, 4282, 87502-210 Umuarama, Paraná, Brazil
Cesumar Institute of Science, Technology and Innovation - ICETI, Av. Guerdner, 1610, Jd. Aclimação, Maringá, Paraná, Brazil

Abstract
The species Ocimum basilicum has many cultivars with different chemotypes. The basil cultivar ‘Albahaca Dante’ has great economic potential. Nevertheless, there is little data about the production of volatiles and the growth using elicitors. This study aims to evaluate growth, physiological disorders, enzymatic activity, biochemistry, stomatal analysis, and the volatile compounds of Ocimum basilicum L.' Albahaca Dante' cultivated in vitro under different concentrations of zinc sulfate (ZnSO4) and methyl jasmonate (MeJa). The experiment was conducted in a completely randomized design (CRD). Five treatments were evaluated based on the combination of MeJa x Zinc Sulfate, using a Murashige and Skoog medium. The results demonstrate that MeJa reduced the formation of abnormal seedlings. Nevertheless, the growth and the number of leaves were not incremented compared in half without elicitors. The number of volatile compounds was lower in the treatment without elicitors and with 25µM ZnSO4 + 1µMMeja. Methyl chavicol was the main compound in both treatments. In this case, the seedlings had smaller stomata with higher density. The seedlings that were developed under unfavorable conditions (75µM ZnSO4 + 1µM MeJa and 75µM ZnSO4 + 5µM MeJa) produced compounds such as Eugenol, Linalool, Methyleugenol, α-Bergamotene, and showed a reduction in the stomatal density, but larger size. The elicitors influenced the activity of antioxidant enzymes, except for 75µM ZnSO4 + 1µM MeJa, which occasioned an acute decrease of all enzymes. The elicitors altered the volatile composition of this basil cultivar and its biochemical responses.

Pages 964-973 | Full Text PDF| doi: 10.21475/ajcs.22.16.07.p3642
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Recovery of three different varieties of tobacco (Nicotiana tabacum L.) under waterlogging stress

Ismul Mauludin Al Habib, Sri Hartatik, Sobir Ridwani, Sholeh Avivi

Biology Education Department, Argopuro PGRI University, Jember, East Java, Indonesia
Departement of Agronomy, Faculty of Agriculture, University of Jember, Jember, East Java, Indonesia
Department of Agronomy and Horticulture, Faculty of Agriculture, Bogor Agricultural University, Bogor, West Java, Indonesia


Abstract
Tobacco plant is one of the high commercial crops that give the largest foreign exchange sources in Indonesia. It also contributes to providing employment not only for farmers but also industrial sectors. Tobacco plant experiences growth failure due to excessive rain, which causes waterlogging to the plants so that the plants become submerged and show hypoxia. A hypoxia tolerant variety is needed to reduce losses in tobacco cultivation. The research was conducted in a greenhouse and biology laboratory at the University of PGRI Argopuro Jember. This research aimed to study the post-hypoxic stress recovery ability in three previously studied varieties of tobacco plants such as sensitive, moderate, and tolerant varieties. The results showed that the treatment of hypoxic stress on tobacco plants significantly affected the parameters of stomatal activity, transpiration rate, and the amount of reducing sugar. In the sensitive and moderate tobacco varieties, the greater percentage of waterlogging resulted in decreased stomatal activity, transpiration rate, and percentage of sucrose. The tolerant tobacco varieties (Bojonegoro var.) show a tendency to increase stomatal activity (76.203, 79.735, 86.963, and 92.227, respectively, for waterlogging 100%, 120%, 140%, and 160% field capacity), transpiration rate (0.139, 0.124, 0.130, and 0.146, respectively, for waterlogging 100%, 120%, 140%, and 160% field capacity), and percentage of sucrose (3.45, 3.64, 3.73, and 4.31, respectively, for waterlogging 100%, 120%, 140%, and 160% field capacity) with a higher percentage of waterlogging. Three varieties of tobacco with tolerant, moderate, and sensitive categories to hypoxia developed different metabolisms to cope with energy crises caused by waterlogging stress comprised of the stomatal conductance, transpiration rate, and sucrose percentage.

Pages 974-981 | Full Text PDF| doi: 10.21475/ajcs.22.16.07.p3645
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Cover crops biomass yield grown as a 2nd summer crop in relation to sowing periods

Karine Fuschter Oligini, Vanderson Vieira Batista, Carlos André Barhy, Paulo César Conceição, Laércio Ricardo Sartor, Paulo Fernando Adami*

Department of Agronomy, Technological University of Paraná, Via do Conhecimento, s/n - km 01 - Fraron, Pato Branco - PR, Brazil, Zip Code 85503-390
Department of Agronomy, Technological University of Paraná, Estrada para Boa Esperança, km 04 - Zona Rural, Dois Vizinhos - PR, Brazil, Zip Code 85660-000


Abstract
The aim of this study was to evaluate cover crop precocity and biomass yield growth as a 2nd summer crop after soybean at different sowing periods (January 2nd; February 2nd and March 2nd at 2019 and January 27th and March 3rd at 2020). Experiment was laid out as a randomized block design in a 3x3 factorial for each sowing period, in the 2019 and 2020 off-seasons, being factor A represented by the cover crops (Urochloa brizantha cultivar Xaraés, Crotalaria juncea cultivar IAC-KR-1 and Pennisetum glaucum cultivar ANm 38,) and factor B by the evaluation periods along cover crops development cycle. There was an interaction between cover crops and evaluation period for plant height and dry matter yield for both years. C. juncea and P. glaucum showed faster growth, regardless of the evaluation period and sowing periods, compared to U. brizantha in both years. Cover crop biomass yield reduced as sowing period is delayed from January to March to an extend that P. glaucum yield dropped from 14.6 to 4.2 t DM ha-1 at 2019 and from 14.4 to 6.9 t DM ha-1 at 2020 as a result shorter photoperiod and lower temperature. The same was noticed to U. brizantha and C. juncea which showed yields of 11.676 and 8.800 and 2.220 and 2.555 kg ha-1 at April 29th of 2019 and 12.507 and 7.812 and 3.041 and 2.346 kg DM ha-1 at June 18th 2020 respectively for January and March sowing periods. U. brizantha and C. juncea are more viable 90 days, while P. glaucum showed the fastest dry matter accumulation rate. All species are viable due to the benefits they provide to the productive system, which becomes more diversified and therefore more sustainable.

Pages 982-989 | Full Text PDF| doi: 10.21475/ajcs.22.16.07.p3652
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Spatial distribution of acidity components and oxidizable carbon fractions in a silvopastoral system

Simone Cândido Ensinas Maekawa, Giselle Feliciani Barbosa, Jefferson Rogério Marques da Silva, Izadora Araujo Oliveira, João Victor Oliveira Rezende, Alan Mario Zuffo*, Fábio Steiner

Department of Crop Production, State University of Mato Grosso do Sul, Glória de Dourados, Mato Grosso do Sul, Brazil
Department of Crop Production, State University of Mato Grosso do Sul, Cassilândia, Mato Grosso do Sul, Brazil
Postgraduate Program in Agronomy, State University of Mato Grosso do Sul, Cassilândia, Mato Grosso do Sul, Brazil
Graduate in Agronomy, State University of Mato Grosso do Sul, Cassilândia, Mato Grosso do Sul, Brazil
Department of Agronomy, State University of Maranhão, Balsas, Maranhão, Brazil
Department of Crop Production, State University of Mato Grosso do Sul, Cassilândia, Mato Grosso do Sul, Brazil


Abstract
The silvopastoral system (SPS) stands out as an agroecological production system that has improved the soil's chemical quality. However, these chemical properties may have distinct changes with greater or lesser distances from the tree row tracks of the silvopastoral system. The objective of this study was to investigate the effects of the distance of the soil sampling points from the eucalyptus tree rows in a 2-year silvopastoral system on acidity components and oxidizable organic carbon fractions of the soil, as well as to compare these chemical properties with the conventional pasture system and native Cerrado vegetation. In the silvopastoral system (SPS), the soil samples were collected at 2.5, 5.0, 7.5, and 10 m of transverse distance from the eucalyptus tree row tracks. Soil samples collected in a conventional pasture area (CP) and a native Cerrado vegetation area (NV) were used as reference treatments. Soil samples were collected at depths from 0.0–0.10, 0.10–0.20, and 0.20–0.30 m. The acidity components (pH, Al3+ and H + Al) and oxidizable organic C fractions (F1: labile fraction; F2: moderately labile fraction; and F3: poorly labile fraction) were determined. The results showed that the lowest soil acidity level was observed at 2.5 and 10.0 m distances from the eucalyptus tree rows. However, the spatial distribution of soil sampling points to the eucalyptus tree rows in a 2-year silvopastoral system did not change the oxidizable fractions of the soil organic carbon. The 2-year silvopastoral system and native Cerrado vegetation area had the highest concentrations of organic carbon in the labile (F1) and poorly labile (F3) fractions in the soil profile compared to the conventional pasture system. A 2-year silvopastoral system in a low fertility tropical soil from the Brazilian Cerrado has not yet been able to improve the soil's chemical quality; therefore, further research should be carried out to investigate the medium and long-term effects of the silvopastoral system on the acidity components and oxidizable organic carbon fractions of the soil.

Pages 990-996 | Full Text PDF| doi:10.21475/ajcs.22.16.07.p3671