Australian Journal of Crop Science   AJCS

Selection of sugarcane clones via multivariate models using near-infrared (NIR) spectroscopy data

Luiz Alexandre Peternelli*, Mateus Teles Vital Gonçalves, Jaqueline Gonçalves Fernandes, Bruno Portela Brasileiro, Reinaldo Francisco Teófilo

Department of Statistics, Universidade Federal de Viçosa (UFV), 36570-900, Viçosa, Brazil
Departament of Exact Sciences, Universidade Federal de Lavras (UFLA), 37200-000, Lavras, Brazil
Department of Plant Sciences, Universidade Federal do Paraná (UFPR), 80035-050, Curitiba, Brazil
Department of Chemistry, Universidade Federal de Viçosa (UFV), 36570-900, Viçosa, Brazil

Abstract
Sugarcane production plays a fundamental role in the Brazilian economy, both for sugar production and renewable energy generation. The development of new cultivars to meet the current needs of the sugarcane industry sector requires efficient phenotyping methods, which should incorporate simplification, speed, accuracy, and consistency. In order to contribute to the development of new phenotyping strategies, this work aimed to develop multivariate regression models using Partial Least Squares (PLS) to classify sugarcane clones based on sugarcane biomass quality parameters, namely fiber (FIB) and apparent sucrose (SC) content. A NIR instrument was used to acquire the reflectance spectra of 196 sugarcane bagasse - collected in two different harvest seasons - and fresh stalk samples. The values predicted by these models allowed the construction of a vector using a confusion matrix that informs whether the clone should be selected or not. PLS models selected to predict each trait under study presented high accuracy and precision, besides small values of false-positive rate and good concordance indication by the Kappa statistic test. The results obtained indicate that the use of fresh stalk samples rather than bagasse samples for the prediction of SC and FIB is recommended as it delivered higher predictive power and is of a more straightforward usage. The utilization of NIR combined with multivariate techniques may help breeding programs in the classification of sugarcane clones based on biomass quality parameters.

Pages 889-896 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p2099
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A modelling assessment of the maize crop growth, yield and soil water dynamics in the Northeast of Brazil

Marshall Victor Chagas Santos*, André Luiz de Carvalho, José Leonaldo de Souza, Mauricio Bruno Prado da Silva, Rui Palmeira Medeiros, Ricardo Araújo Ferreira Junior, Gustavo Bastos Lyra, Iêdo Teodoro, Guilherme Bastos Lyra, Marco Antonio Maringolo Lemes

Department of Agricultural Engineering, Federal University of Viçosa, Viçosa-MG, Brazil
Department of Agrometeorology, Federal University of Alagoas, Maceió-AL, Brazil
Department of Rural Engineering – São Paulo State University, Botucatu-SP, Brazil
Department of Environmental Sciences, Federal Rural University of Rio de Janeiro, Seropédica-RJ, Brazil

Abstract
The present study aims to evaluate the APSIM-Maize model performance to use it as a decision-making tool to help improve production rates, reduce production costs and assess the potential impacts of climate change on crop yields in the Northeast of Brazil. The crop, soil and weather data used in the simulations were obtained from field experiments carried out in maize crops in 2008 and 2011 in two different edaphoclimatic regions in Alagoas State, Northeast Brazil. The approach we used explored the ability of APSIM to simulate growth variables and soil water dynamics of a maize variety (AL Bandeirante). During parametrization, we made some adjustments regarding the variety and soil organic matter to attain a better representation of the growth and soil water dynamics, respectively. The APSIM-Maize model predicted the leaf area index with a RMSE (Root Mean Square Error) ranging between 0.14 and 1.06 cm2 cm-2 and the biomass production with an RMSE between 2.30 and 3.34 Mg ha-1. The volumetric soil water content was satisfactorily predicted with RMSE ranging between 0.02 and 0.08 mm mm-1. Results showed that this model is a useful tool for decision-making, which can be potentially used as a support in climate risk management and policies, aiming to improve regional production, provided it has been previously validated with independent datasets.

Pages 897-904 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p1410
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Osmoprotectant in soybean seeds can increase the inoculation and co-inoculation time in pre-sowing

Glauber Monçon Fipke, Thomas Newton Martin, Tânia Maria Müller, Vinícius dos Santos Cunha, Janete Denardi Munareto, Alex Tagliapietra Schönell, Luiz Fernando Teleken Grando, Anderson da Costa Rossato

Department of Plant Science, Federal University of Santa Maria, Santa Maria, RS, Brazil
Department of Agronomy, University of Western Santa Catarina, Maravilha, SC, Brazil
Department of Plant Breeding, Monsanto Company, Rolândia, PR, Brazil

Abstract
The practice of soybean seed inoculation cannot exceed the 24-hour prior to sowing. The objective of this study was to assess the effects of inoculation and co-inoculation of osmoprotectant soybean seeds, performed at different times of sowing. The experiments were conducted during two crop seasons at "sandy clay loam Acrisol" and "Cfa climate" in Santa Maria, RS, Brazil. The experimental design consisted of completely randomized blocks with four replications. Nine distinct treatments of seeds inoculation were carried out with bacteria of the genus Bradyrhizobium were inoculated alone (conventional inoculation) or combined with Azospirillum brasilense (co-inoculation), associated with the use of osmoprotectants. The components of nodulation, leaf chlorophyll, plant growth and grain yield were evaluated. The number of nodules and pods per plant are the variables most correlated with grain yield. Number of grains per pod, mass of thousand grains, and A, B and total chlorophyll content were not influenced by inoculation, co-inoculation and nitrogen fertilization. All treatments that used osmoprotectant had an increased 30% (in the first year) at average number of nodules in V5 compared to the treatments that did not use it. Co-inoculation provided an increase of 31% and 16% of yield, respectively, compared to the no-inoculation treatment, for the first and second experimental years. Inoculation and co-inoculation when carried out seven days before sowing and associated with the use of the osmoprotector, provides grain yield similar to the inoculation performed at the time of sowing.

Pages 905-912 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p1696
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Spatial arrangement of plants on leaf growth and development and the yield potential of soybean

José Eduardo Minussi Winck, Thomas Newton Martin*, Marlo Adriano Bison Pinto, Lucas Allan Bruning, Guilherme de Almeida Arismendi

Universidade Federal de Santa Maria (UFSM), Av. Roraima, n° 1000, Cidade Universitária, Camobi, Santa Maria – RS, Brasil

Abstract
This study aimed at determining the effect of a variety of plants arrangements on foliar growth and development as well as the productive potential in soybean. The field experiment was performed over two agricultural years (2015/16 and 2016/17) on argisoil in the environmental subtropical. The two cultivars selected, viz., BMX Tornado RR and FPS Urano RR were sown in four types of spatial distribution of the plants, viz., conventional spacing (0.45 m spacing between rows), reduced spacing (0.225 m spacing between rows), paired spacing (two rows with 0.225 m and 0.45 m spacing from the other rows) and crossed spacing (0.45 m spacing between the rows with crosses of two rows, at a 90° angle). The randomized block design was adopted for the experiments, with the treatments in a 2x4 factorial distribution, and four replications; the first factor included the cultivars and the second the four types of plant distribution. Plant arrangement affected the plant profile with respect to the behavior of the ecophysiological variables like the plastochron, leaf life time and yield distribution. Leaf life in each stratum was caused by the foliar senescence rhythm, explained by a 4th degree polynomial model, revealing two peaks in the senescence rate, one during pre-flowering stage and the other when the grain filling stage was completed. Changes in conventionally used spacing are not recommended.

Pages 913-922 | Full Text PDF| Supplementary Data PDF| doi: 10.21475/ajcs.20.14.06.p1721
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Ecophysiology of cowpea (Vigna unguiculata L.) cultivated under different saline and biofertilizer levels

Rafael Santiago da Costa*, Letícia Kenia Bessa de Oliveira, Aiala Vieira Amorim, Fred Denilson Barbosa Silva, Albanise Barbosa Marinho, Sebastião Medeiros Filho, Rosilene Oliveira Mesquita

Department of Agronomy/Plant Science, Federal University of Ceará, Fortaleza, Ceará, Brazil
Institute of Rural Development, University for the International Integration of Afro-Brazilian Lusophony, Redenção, Ceará, Brazil

Abstract
The objective of this study was to evaluate the growth, physiology, and production of cowpea plants grown under different levels of salinity and doses of mixed biofertilizer. The experiment was set in a completely randomized 3 x 4 factorial design, corresponding to three levels of irrigation with saline water (ECw: 0.5, 2.5 and 4.5 dS m-1) and four doses of biofertilizer (0, 800, 1600 and 2400 milliliters - mL), with five repetitions. The biofertilizer was obtained by means of an aerobic process, using a mixture of water, goat manure, and wood ashes, and it was applied in the liquid form, once a week, and directly into the soil. After 70 days, gaseous exchanges were evaluated, and the length of the main stem, the diameter of the stem, and the leaf area were measured. Furthermore, the number of pods produced, mean pod size, total pod weight, total seed weight, hundred seed weight, and yield were estimated. It was observed that the application of mixed biofertilizer promoted increments of 28.98% in leaf area, 32.78% in length of the main stem, and 21.55% in total dry mass. Weekly doses of 1600 mL promoted significant increases in gas exchanges. The application of weekly doses of 1600 mL of mixed biofertilizer promoted growth increases in physiological and productive parameters when the plants were irrigated with saline water up to 2.5 dS m-1, suggesting that the biofertilizer reduces the deleterious effects of salinity.

Pages 923-931 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p2048
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Soil humidity as a productive conditioner of soybean culture through inoculation, co-inoculation and rooting

Evandro Ademir Deak, Thomas Newton Martin*, Glauber Monçon Fipke, Jessica Deolinda Leivas Stecca, Vinícius dos Santos Cunha

Department of Crop science, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil

Abstract
In the soybean crop, the practice of inoculation is crucial for producing high yields. This is because biological nitrogen fixation (BNF) is the main supplier of the nutrient demand for this crop. However, a few environmental variables can also greatly influence the survival of the bacteria that control this process. In this context, the present work was performed to confirm the many ways in which soil moisture affects this process. In the field, we conducted two experiments at the times of the two sowing dates, 11/24/2015 and 12/17/2015, adopting the factorial 7 x 2 design, with four replications. The inoculation treatments included, non-inoculated (NI); not inoculated along with the nitrogen supplied at the 200 kg ha-1 (NI+N) dosage; inoculation with Bradyrhizobium [I (Brady)]; root enhancers (R); inoculation with Bradyrhizobium + root enhancers (I+R); co-inoculation with Bradyrhizobium + Azospirillum brasilense (I+Azo); co-inoculation with Bradyrhizobium + Azospirillum brasilense + root enhancers (I+Azo+R). The second factor included was the use or absence of a water jet (200 L ha-1) directed onto the seeds in the sowing furrow. Then estimations of the initial establishment of the plants, nodulation, and productivity components were measured. Water supplied to the sowing furrow had no effect on soybean nodulation and yield components. Co-inoculation promoted nodulation in soybean plants, particularly in dry mass of the nodules and number of nodules per plant.

Pages 932-939 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p2133
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Antagonistic potential and histopathology of Meloidogyne javanica on Macrotyloma axillare cv. Java

Angélica Miamoto, Andressa Cristina Zamboni Machado, Orazília França Dorigo, Thaísa Muriel Mioranza, Heriksen Higashi Puerari, Beatriz Almeida e Silva, Vítor Vargas Schwan, Cláudia Regina Dias Arieira

State University of Maringá, Post Graduate in Agronomy, Maringá, PR, Brazil
Agronomic Institute of Paraná, Londrina, PR, Brazil
State University of Maringá, Department of Agronomic Science, Umuarama, PR, Brazil

Abstract
Root-knot nematodes are obligate parasites, so changes at their feeding sites can limit their development. Alterations to feeding sites is one of the main actions taken by antagonistic plants. The aim of this study was to assess the response and histopathology of interactions between Meloidogyne javanica and the roots of Macrotyloma axillare cv. Java. The penetration and development of the nematode was assessed from 8 to 30 days after inoculation (DAI) with 3000 eggs + second-stage juveniles (J2) of M. javanica. The reproduction factor (RF) was assessed at 60 DAI, with two inoculation levels, 700 and 1000 eggs + J2, and the changes in the development and histopathology of M. javanica was assessed at 10, 15 and 30 DAI. Suscetible soybean was used as a control. The development of nematodes at the third (J3) and fourth juvenile (J4) stages was delay, despite the presence of J2 inside the roots, and no adult females were found in the M. axillare cv. Java roots. RF was 0.31 and 0.39 for M. axillare cv. Java and 3.40 and 4.52 for soybean at inoculation levels of 700 and 1000 eggs + J2, respectively. The feed cells in M. axillare cv. Java could not effectively nourish the nematode, which led to deformed females 30 DAI. The feed cells and nematode development, however, were normal in soybean. M. axillare cv. Java was resistant to M. javanica and had an antagonistic potential, because it did not prevent the nematode from penetrating the roots but had a negative effect on M. javanica due to the inefficiency of the feeding site.

Pages 940-946 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p2153
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Sweet corn in no-tillage system on cover crop residues in the Brazilian Cerrado

Kaiê Fillipe Guedes Miranda, José Luiz Rodrigues Torres*, Hamilton Cesar de Oliveira Charlo, Valdeci Orioli Junior, João Henrique de Souza. Favaro, Zigomar Menezes de Souza

Plant Production, Federal Institute of Education, Science and Technology, Triângulo Mineiro (IFTM), Campus Uberaba. St. João Batista Ribeiro, 4000. Zip code 39064-790. Uberaba, Brazil
IFTM. Campus Uberaba, Brazil
Agronomy, IFTM (Agrisus Foundation Scientific Initiation Scholarship). Campus Uberaba
University of Campinas (UNICAMP), School of Agricultural Engineering (FEAGRI). Av. Cândido Rondon, 501. Zip code: 13.083-875. Campinas, Brazil

Abstract
In recent years, the growth of the cultivated area with sweet corn in conventional tillage system in Brazil expanded, although crops can be grown on different residues of cover crops, which improve nutrient cycling and crop productivity. The objective of this study was to evaluate the biomass production and to quantify the rate of plant residues decomposition of different cover crops, and correlate the results with the production and grain yield of sweet corn in an area located in the Cerrado biome. The experimental design used was randomized blocks with eight treatments: PM - pearl millet; SH - sunn hemp; SG - signal grass; PM + SH; PM + SG; SH + SG; PM+ SH + SG; FW - fallow (spontaneous vegetation), which preceded the cultivation of sweet corn. Fresh biomass (FB) and dry biomass (DB) of the cover crops were evaluated, as well as the rate of plant residue decomposition. Sweet corn productivity, straw and corncob weight, and grain yield were also determined. Pearl millet presented a better performance in FB production, decomposition rate, residue half-life (T½ life) in soil, yield, corn cob strawweight and yield of sweet corn. Pearl millet, when mixed with other plants, presented reduced rate of residue decomposition and increased residue T½ life. The FW presented the lowest biomass production, with great rate of decomposition and low T½ life. Cover crops grown before sweet corn in soils of good fertility did not affect crop agronomic characteristics. Pearl millet is the best cover crop adapted to Cerrado Brazilian climatic conditions to be used in monoculture or in mixtures with other plants.

Pages 947-952 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p2189
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Application of tamarind seed starch as edible coating in the post-harvest quality of grapes ‘Isabel’ (Vitis labrusca × Vitis vinifera L.)

Bárbara Genilze Figueiredo Lima Santos, Albert Einstein Mathias de Medeiros Teodosio, Railene Hérica Carlos Rocha Araújo, Elny Alves Onias, Agda Malany Forte de Oliveira, Elidayane da Nóbrega Santos, Rita Magally Oliveira da Silva Marcelino, Jaína Geovana Figueiredo Lima Santos

Federal University of Campina Grande, Pombal, Paraíba, Brazil
Federal University of Paraíba, Areia, Paraíba, Brazil

Abstract
The Isabel grape (Vitis labrusca × Vitis vinifera L.) is the most produced grape in Brazil, however, it has a short postharvest period due to rapid degradation during storage. The use of coating has been an alternative to prolong the shelf-life of fruits. The objective of this work was to evaluate the postharvest quality of 'Isabel' grapes coated with tamarind (Tamarindus indica L.) seed starch. The experimental design was completely randomized with five treatments with edible coating based on tamarind seed starch, at concentrations of 0, 0.5, 1, 1.5 and 2% and five replications. The grapes were immersed in the solutions with different concentrations and stored in B.O.D. at 12 ± 2 ° C and 85 ± 5% relative humidity for 12 days. Weight loss, color, pH, soluble solids, total titratable acidity, relationship between soluble solids and acidity, anthocyanins, flavonoids and vitamin C were evaluated. The 2% coating of tamarind seed starch was the most efficient, providing shelf life in 12-day grapes when stored at 12 ± 2 ° C and 85 ± 5% RH, and maintaining the main quality aspects, with higher SS / TA ratio and vitamin C.

Pages 953-958 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p2250
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Morphological and phytochemical analysis of leaves and stems of Tetrapterys multiglandulosa CAV.

Gilberto Gonçalves Facco*, Eloty Justina Schleder, Natalia Yoshioka de Vidis, Maristela Halverson, Rosemary Matias, Marcos Barbosa-Ferreira, Doroty Mesquita Dourado, Carlos Eurico dos Santos Fernandes

Graduate Program, Mestrado Profissional em Produção e Gestão Agroindustrial, Anhanguera – Uniderp University, Campo Grande, MS, Brasil
Anhanguera – Uniderp University, Campo Grande, MS, Brasil
Anhanguera – Uniderp University, Campo Grande, MS, Brasil
Graduate Program, Meio Ambiente e Desenvolvimento Regional, Anhanguera – Uniderp University, Campo Grande, MS, Brasil
FAMEZ/UFMS, Campo Grande, MS, Brasil

Abstract
This study aimed to carry out morphoanatomical, histochemical and phytochemical analysis of leaves and stems of Tetrapterys multiglandulosa Cav. (Malpighiaceae), a native plant responsible for abortion and sudden death in beef cattle. Plant specimens underwent anatomical study, in which leaves and stems were dried and ground with aqueous and ethanol extracts subjected to histochemical and phytochemical analysis. Anatomical observation of vegetative organs detected the presence of simple columnar cells in the adaxial epidermis, palisade mesophyll, parenchyma with a layer of cells and paracitic type stomata. Stem cross-sections presented circular section, single layer (uniseriate) epidermis with thick cuticle and Malpighi’s trichomes, the phelogen was in differentiation. The cortex showed angular collenchyma, parenchyma with exogenous channels and druse shaped calcium oxalate crystals. Phytochemical tests of aqueous and ethanol extracts of leaves and stems indicated the presence of phenolic compounds, tannins, flavonoids, saponins, alkaloids and cardiotonic heterosides. Potentially phytotoxic secondary metabolites evidenced in the leaves and stems, including saponins and cardiotonic heterosides were correlated with clinical signs observed in intoxicated animals.

Pages 959-964 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p2284
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Root biomass and production of cotton cultivars subjected to saline water irrigation

André Alisson Rodrigues da Silva*, Márcia Cristina de Araújo Pereira, Luana Lucas de Sá Almeida Veloso, Ronaldo do Nascimento, Elka Costa Santos Nascimento, Carlos Vailan de Castro Bezerra, Mateus Costa Batista, Robson Felipe de Lima

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

Abstract
Water scarcity and high levels of salinity in irrigation water limit irrigated cotton cultivation in the semiarid region of Northeast Brazil. So, it is necessary to adopt cultivation strategies that make the production system feasible. In this context, the present study aimed to evaluate the biomass and production of cotton cultivars subjected to different levels of saline water irrigation. The experiment was carried out under greenhouse conditions, with treatments distributed in a completely randomized design, in a 5 x 2 factorial arrangement, corresponding to five levels of irrigation water electrical conductivity - ECw (1.5, 3.0, 4.5, 6.0 and 7.5 dS m-1) and two cotton cultivars (BRS 368 RF and BRS Safira), with 4 replicates. Treatment effects were measured by the number of bolls per plant, lint weight, number of seeds per plant, total weight of seeds and dry and fresh biomass of stem, roots and leaves. Irrigation using water with electrical conductivity from 1.5 dS m-1 negatively affects the production of the cotton cultivars BRS SAFIRA and BRS 368 RF, causing reductions in all production variables analyzed. The cultivar BRS Safira has better production performance than BRS 368 RF when exposed to water salinity.

Pages 965-970 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p2301
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Effect of biochar and inoculation with Trichoderma aureoviride on melon growth and sandy Entisol quality

Erika Valente de Medeiros*, Marcele de Cássia Henriques dos Santos Moraes, Diogo Paes da Costa, Gustavo Pereira Duda, Julyana Braga de Oliveira, Jenifer Sthephanie Araujo da Silva, José Romualdo de Sousa Lima, Claude Hammecker

Laboratory of Microbiology, Federal Rural University of Pernambuco, Garanhuns, PE, Brazil
IRD/UMR Eco & Sol, place Pierre Viala, 2, 34060 Montpellier, France

Abstract
The melon belongs to the family of commercially important cucurbitaceous in the world. However, the production of this crop can be very problematic in some places due to management practices and the climatic instability. Amongst the different options available to overcome these obstacles, the use of biochar often promoted for providing multiple benefits to crops, could contribute in holding more water and nutrients in soil and therefore improve the plant growth. A second way to try to improve the plant development was to use Trichoderma (TRI) known as aiding in seed germination, and being an excellent biological control agent against plant pathogenic pests. So, the objective of this study was to evaluate the benefits of the association of biochar and TRI on the initial growth of melon and the effects on the quality of a sandy Entisol. We quantified the effects of these associations through biometric growth in melon plants and chemical, microbial, and enzymatic activities of the biogeochemical cycles in the soil. An experiment in a completely of randomized design was performed in a factorial scheme (3 x 2 + 1) with three sources of biochar (bean husk (BH), coffee ground (CG), and coffee husk (CH)) inoculated with (T+) or without (T-) TRI and additional controls When the coffee grounds (CG) and bean husks (BH) biochar with T+ soil was inoculated, the fresh weight (number of leaves), dry weight, length (of roots and branch), soil acid and alkaline phosphatase, total organic carbon, phosphorus, magnesium, potassium, and pH were all increased. Moreover, T. aureoviride inoculated CG biochar compared to the control increased the shoot length and dry biomass of the melon plant in 30 and 22% between 22 and 30 %. The soil that received coffee husks (CH) biochar and T+ showed higher microbial biomass carbon. However, the melon plants responded more to the type of biochar than to the T. aureoviride inoculation, possibly due to the short growth time of melon. Results of BH biochar inoculated with T. aureviride in sandy soil showed improved efficiency on melon growth and increased soil quality.

Pages 971-977 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p2302
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Nitrogen fertilisation in tropical pastures: what are the impacts of this practice?

Antonio Leandro Chaves Gurgel*, Gelson dos Santos Difante, Denise Baptaglin Montagner, Alexandre Romeiro de Araújo, Alexandre Menezes Dias, Juliana Caroline Santos Santana, Jéssica Gomes Rodrigues, Marislayne de Gusmão Pereira

Faculty of Veterinary Medicine and Animal Science, Federal University of Mato Grosso do Sul, Avenida Senador Filinto Müller, 2,443, Campo Grande, CEP 79074-460, Mato Grosso do Sul, Brazil
Embrapa Beef Cattle, Campo Grande, Brazil, Av. Rádio Maia, 830 - Vila Popular, CEP. 79106-550, Campo Grande, Mato Grosso do Sul, Brazil
Academic Unit Specialized in Agricultural Sciences, Federal University of Rio Grande do Norte, Rodovia RN 160, Km 03, s/n - Distrito de Jundiaí, Macaíba - RN, CEP 59280-000, Rio Grande do Norte, Brazil

Abstract
It is estimated that approximately 47% of the world’s ruminant meat and milk is produced in tropical and subtropical regions, with pasture comprising the main food base of these animals. Nitrogen fertilisation is an essential practice for the maintenance of pasture productivity, considering that a deficiency of this nutrient is a primary factor in triggering pasture degradation. In addition to directly influencing the photochemical and biochemical phases of photosynthesis, nitrogen stimulates enzyme activity and the synthesis of enzymes responsible for fixing CO2 (Rubisco in C3 plants and phosphoenolpyruvate carboxylase in C4 plants), thus increasing the efficiency of atmospheric CO2 capture. All of these physiological processes are easily observed macroscopically in the characteristics of forage plants. This review examines the impact of nitrogen fertilisation in tropical pastures on the main components of production systems (soil, plants and animals), describes the results obtained in different situations and highlights the most efficient ways of producing meat without environmental impacts.

Pages 978-984 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p2357
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Productive performance and quality of arugula (Eruca sativa) under different doses of cassava wastewater containing potassium source

Anderson Vitor Lins da Silva, Aldair de Souza Medeiros, Giordano Bruno Medeiros Gonzaga, Ivomberg Dourado Magalhães, Renato Américo de Araújo Neto, Rener Luciano de Souza Feraz*, Sebastião de Oliveira Maia Júnior, Luan Danilo Ferreira de Andrade Melo, Patrícia da Silva Costa, Thiago Alves Pimenta, Joicy Lima Barbosa, Mariana de Oliveira Pereira

Department of Plant Production, Federal University of Alagoas, Rio Largo, Brazil
Department of Engineer, "Mauricio de Nassau" University Center, Maceio, Brazil
Department of Agroecology and Agriculture, State University of Paraíba, Lagoa Seca, Paraíba, Brazil
Agricultural Engineering Academic Unit, Federal University of Campina Grande, Campina Grande, Paraíba, Brazil
Department of Plant Protection, Federal University of Alagoas, Rio Largo, Brazil
Fellow of CAPES Postdoctoral, PNPD, Brazil
Fellow of CNPq Postdoctoral, PDJ, Brazil

Abstract
Cassava wastewater has high organic load and concentration of nutrients and can cause damage to the environment when discarded indiscriminately. However, the residue can help agricultural production. Therefore, this study aimed to determine the appropriate doses of cassava wastewater to enable the highest production and quality of arugula. The experiment was conducted in a greenhouse, in a completely randomized design, consisting of eight treatments composed of the following doses: D1 = 0, D2 = 6.5, D3 = 13, D4 = 19.5, D5 = 26, D6 = 32.5, D7 = 39 and D8 = 45.5 m3 ha-1 of cassava wastewater with four replicates each. We used the arugula cultivar “Cultivada”, and samples of plant height, fresh matter, and shoot dry matter were performed at 15 and 30 days after emergence. The quality of arugula was evaluated through pH, total soluble solids and titratable total acidity. Cassava wastewater had a significant effect on plant height, fresh matter and dry matter of above ground part, pH and total soluble solids of arugula. However, titratable total acidity was not affected by treatments. Our results show that cassava wastewater is a good alternative fertilizer for arugula cultivation but at proper doses up to 26 m3 ha-1 applied through the crop cycle to avoid the deleterious effect of some nutrients in excess, such as potassium.

Pages 985-990 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p2391
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Assessment of insecticide mortality on fall armyworm (Spodoptera frugiperda) between locations and modes of insecticide entry

Karina da Silva*, Márcia A. Smaniotto, Jefferson G. Acunha, Monique D’Agostini, Ariel Rizzardo, Luis E. Curioletti, Larissa Pasqualotto, Ricardo Froehlich, Clerison R. Perini*

Department of Entomology, Federal Institute of Education, Science and Technology of Rio Grande do Sul - Campus Sertão, Rodovia RS 135 - km 25, Dt. Engenheiro Luiz Englert, Sertão – RS, Brazil
Department of Entomology, Federal Institute of Education, Science and Technology of Rio Grande do Sul - Campus Bento Gonçalves, Osvaldo Aranha Av 540, Bento Gonçalves – RS, Brazil
Department of Plant Protection, Federal University of Santa Maria, Roraima Av 1000, CCR, 44G, Santa Maria - RS, Brazil

Abstract
Spodoptera frugiperda is a major pest of maize and plants expressing insecticide proteins from Bacillus thuringiensis. Control programs based on Bt maize events have increased inefficacy for this pest, often demanding insecticide sprays as a complementary measure. The aim of this work was to evaluate larval mortality in two S. frugiperda populations submitted to different insecticide sprays and modes of entry into the insect’s body. Experimental design was completely randomized with a factorial scheme 4×2×2, plus one check. Four insecticides [azadirachtin (12 g a.i. L-1), lambda-cyhalothrin (50 g a.i. L-1), teflubenzuron (150 g a.i. L-1), flubendiamide (480 g a.i. L-1)], two modes of entry for each insecticide (topic contact and ingestion) and two S. frugiperda populations (from Constantina and Sertão) were tested. The mortality of individuals was assessed daily for 15 days after treatment spraying. The insecticides teflubenzuron and flubendiamide presented the highest mortality levels of S. frugiperda, disregarding the differences between tested populations and modes of entry. Contamination by ingestion resulted in higher mortality, especially for teflubenzuron and flubendiamide. The results suggest that S. frugiperda from Constantina are less susceptible to the insecticides evaluated.

Pages 991-996 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p2403
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Sustainability of cocoa production in Indonesia

Muhardi*, Abdul Rahim, Effendy, Made Antara, Rustam Abdul Rauf, Arifuddin Lamusa, Christoporus, Hadayani, Dian Safitri, Jangkung Handoyo Mulyo

Department of Agrotechnology, Tadulako University, Palu, Indonesia 94118
Department of Agriculture Economics, Tadulako University, Palu Indonesia 94118
Department of Agricultural Socio-Economics, Gadjah Mada University, Yogjakarta, Indonesia 55281

Abstract
The objective of this study was to present empirical evidence about the sustainability of cocoa farming in Indonesia and how decisions are made in producing cocoa beans. This study used a survey method involving a questionnaire for collecting data. The results showed that the sustainability of cocoa farming was determined by weak sustainable ecological factors (46.07%), moderately sustainable socioeconomic factors (54.43%), moderately sustainable technological factors (55.95%), moderately sustainable factors that help farmers in cocoa farming (59.60%), and weak sustainable factors in cocoa farming families' futures (47.52%). To increase the sustainability of cocoa farming, the current study found that farmer education, cocoa crop rejuvenation, cocoa pest and disease control, cleanliness and quality of cocoa beans, cocoa productivity, institutions, extension, technology, credit availability, and stability of cocoa bean prices are the most important factors to be improved.

Pages 997-1003 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p2510
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Strategy of nitrogen fertilizer application to increase growth and yield of rice in ratoon system at tidal swampland

Gribaldi Gribaldi*, Nurlaili Nurlaili, Firnawati Sakalena, Nurmala Dewi, Ardi Asroh

Departemen of Agrotecnology, Faculty of Agriculture, University of Baturaja, Jl. RatuPenghulu No. 02301 Karang Sari Baturaja 32115, South Sumatra, Indonesia

Abstract
This study aims to determine the effect of regulating the provision of nitrogen fertilizer on several rice varieties on the growth and yield of rice in ratoon system at the Tidal swampland. A split plot design was employed in this experiment. The main plot was nitrogen fertilizer application (N) consisting of N1, N2, N3, and N4. The subplot is rice varieties (V) consisting of Inpari 30 (V1), Inpara 3 (V2), Inpari 33 (V3), Inpari 43 (V4) and Hipa 5 Ceva (V5). The results showed that ½ dose nitrogen fertilization given at planting + ½ dose at primordia had a good effect on the growth and yield of the main crop, whereas 1/3 dose nitrogen fertilization given at planting + 1/3 dose at primordia + 1/3 dose at harvest tends to have a good effect on ratoon yield. Variety Hipa 5 Ceva produced highest yield of unhusked rice (i.e. 4.9 tons ha-1 for the main crop and 2.71 tons ha-1 for ratoon) at (N3): 135 kg N ha-1 fertilizer, when ½ dose was given at planting + ½ dose at primordia. The variety Hipa 5 Ceva with various nitrogen fertilization strategies provided the highest total grain yield in the ratoon system at tidal swampland.

Pages 1004-1010 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p2524
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Performance of arabica coffee accessions from the active germplasm bank of Minas Gerais – Brazil as a function of dry and wet processing: a sensory approach

Larissa de Oliveira Fassio, Marcelo Ribeiro Malta*, Gilberto Rodrigues Liska, Gladyston Rodrigues Carvalho, Cesar Elias Botelho, Antônio Alves Pereira, Rosemary Gualberto Fonseca Alvarenga Pereira

Empresa de Pesquisa Agropecuária de Minas Gerais/EPAMIG - Avenida José Cândido da Silveira, 1647 - Bairro União - 31170-495 - Belo Horizonte, MG, Brasil
Department of Agroindustrial Technology and Rural Socioeconomics, Federal University of São Carlos, Araras, SP, 13600-970, Brazil
Universidade Federal de Lavras/UFLA - Departamento de Ciência dos Alimentos/DCA - Caixa Postal 3037 - 37200-000 – Lavras, MG, Brasil

Abstract
The post-harvest processing of coffee is one of the most important factors in obtaining a superior quality product with differentiated attributes in the cup. The objective of this study was to evaluate the influence of wet and dry postharvest processing on beverage quality and on the sensory profile of 49 Coffea arabica accessions from the Active Germplasm Bank of Minas Gerais. For this purpose, the sensory analysis was applied based on the protocols of the Specialty Coffee Association, and the data were analyzed by Principal Component Analysis. Some coffee accessions were separated by the final score according to the type of processing used. However, the influence of the processing method was most evident in the individual scores for sensory attributes. Regardless of the processing method, some accessions presented stability for the notes of taste, acidity, fragrance, body, aftertaste, balance, global impression as well as for the final score. The Coffea arabica accessions of the Active Germplasm Bank of Minas Gerais presented variability in the sensory profile of the beverage according to the type of postharvest processing used.

Pages 1011-1018 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p2528
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Determination of raw biomass, yield and income from intercropping models of coffee (Coffea canephora Pierre) compare with perennial trees in tropical climate

Phan Van Tan*, Huynh Van Quoc and Dang Thi Thuy Kieu

Agriculture and forestry faculty, Taynguyen Uni., Buonmathuot city, Daklak province, Vietnam

Abstract
This is the first report of evaluation of 4 Robusta coffee intercropping models (Coffea canephora Pierre var. Robusta) with perennial trees (Siamese cassia and durian) on Rhodic ferrasol soil and tropical climate. The models were: T0 - sole coffee, T1 - intercrop of coffee with Siamese cassia (Cassia siamea Lam.), T2 – intercrop of coffee with durian (Durio zibethinus Murr.) at 9 x 9 m distance and T3 – intercrop of coffee with durian at 9 x 6 m distance. The results showed that the raw biomass increased from 71.6 tons ha-1 (T0) to 101.4 tons ha-1 (T1) or to 176.4 tons ha-1 (T2) or to 178.6 tons ha-1 (T3). The yield of dry coffee beans in T2 model was reduced by 300 kg ha-1 and by 1,000 kg ha-1 in T3 model, respectively, compared with T0 (4,120 kg.ha-1). However, they are in the same level with T1 (4,202 kg ha-1). The T2 and T3 models produced 22 and 23 tons ha-1 of durian fruits, respectively. Currently, planting of coffee solely or intercropping with forestry trees are popular methods of growers. We recommend that farmers should intercrop coffee with perennial fruit trees, which creates higher total-income and larger raw biomass.

Pages 1019-1023 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p2534
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Greenhouse gas emission from the soils fertilized with liquid pig slurry (LPS) in Tifton 85 bermudagrass pasture in tropical savanah

Adilson Amorim Brandão*, Eduardo Guimarães Couto, Renato de Aragão Ribeiro Rodrigues, Oscarlina Lúcia Santos Weber, Osvaldo Borges Pinto Júnior

Federal Institute of Mato Grosso do Sul, Naviraí, 79950-000, Mato Grosso do Sul, Brazil
Federal University of Mato Grosso, Department of Soils and Rural Engineering, Cuiabá, 78060-900, Mato Grosso, Brazil
Embrapa Soils, Rio de Janeiro, 22460-000, Rio de Janeiro, Brazil
University of Cuiabá, Cuiabá, 78065-900, Mato Grosso, Brazil

Abstract
Soils have important roles in the global budgets of the greenhouse gases. The liquid pig slurry (LPS) in pastures has high potential as a fertilizer but could have a direct influence on emission of greenhouse gasses. This study evaluated the effects of the application of LPS and inorganic mineral fertilization during the rainy and dry seasons on the emissions of CO2, CH4 and N2O in pastures planted with Tifton-85. The following treatments were tested: Control - no fertilization; LPS30 - 30 m3 ha-1; LPS60 - 60 m3 ha-1; LPS90 - 90 m3 ha-1 and inorganic mineral fertilization. Gasses were sampled using static chambers first during the months of March and April, then in June and July. Fertilization with LPS caused an increase in the flux of CO2 and CH4 during the first hours after its application, and CO2 emissions are greater during the rainy than in the dry season. However, the application of LPS in Tifton-85 pasture during rainy periods did not show high potential for emission of CO2, in contrast to application during the dry season. Fertilization with LPS increases the emission of N2O, and this varies as a function of the volume of LPS applied and the experimental conditions experimental conditions. The application of LPS in Tifton-85 pasture has a high potential for N2O emission during the rainy season, but the magnitude is similar to that resulting from inorganic mineral fertilization.

Pages 1024-1031 | Full Text PDF| doi: 10.21475/ajcs.20.14.06.p2582