Coffea arabica cultivars with resistance to nematode Meloidogyne exigua originated from Costa Rica
Mainor Rojas Barrantes, Daniel Ramírez Valerio, Luis Salazar Figueroa, Tumoru Sera, Gustavo Hiroshi Sera*
Instituto del Café de Costa Rica (ICAFE), Heredia, Costa Rica Laboratorio Nemafito, San José, Costa Rica
Instituto Agronômico do Paraná (IAPAR)/ Plant Breeding Department. Rodovia Celso Garcia Cid Km 375. CEP 86047-902, Três Marcos, PO Box 481, Londrina, PR, Brazil
Abstract
The nematode Meloidogyne exigua causes moderate losses in almost all coffee plantations in Costa Rica. The objective of this research was to evaluate the resistance of Coffea arabica cultivars developed in Brazil to M. exigua native from Costa Rica. The trial was carried out in Heredia, Costa Rica. A randomized complete block design with five replications was used to evaluate the cultivars Caturra, Catuaí Vermelho IAC 99, IAPAR 59, IPR 98, IPR 99, IPR 100, IPR 102, IPR 103, IPR 106 and IPR 107. The plants were grown in pots and inoculated with 2500 eggs + J2 117 d after the transplant. The evaluation was performed 209 d after the inoculation considering the number of eggs + J2 in 100 g of roots and the estimation of gall index (GI) of each plant. The reduction in the reproduction factor showed resistance for the cultivars IPR 99, IPR 100, IPR 102, IPR 103 and IPR 107. This represents a great possibility to face M. exigua of Costa Rica in a sustainable way with varieties developed in Brazil.
Pages 1-6 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p1328
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Recovery and seeds germination of four important tropical forage legumes in bovine dung
Bruno Borges Deminicis*, Henrique Duarte Vieira, João Carlos de Carvalho Almeida, Tiago Neves Pereira Valente, Saulo Alberto do Carmo Araújo, Renata Vianna Lima
Universidade Federal do Sul da Bahia, Teixeira de Freitas, BA 45990-000 Brazil
Universidade Estadual do Norte Fluminense Darcy Ribeiro, Campos dos Goytacazes, RJ 28013-600 Brazil
Universidade Federal Rural do Rio de Janeiro, Seropédica, RJ 23890-000 Brazil
Instituto Federal Goiano, Posse Campus, GO 73900-000, Brazil.
Universidade Federal dos Vales do Jequitinhonha e Mucuri, Unaí, MG 38610-000 Brazil
Instituto Federal de Educação, Ciência e Tecnologia do Espírito Santo, Colatina, ES 9709-800 Brazil
Abstract
This experiment was conducted to evaluate the recovery and survival of tropical forage legume seeds (butterfly pea, stylosanthes, perennial soybean and macrotiloma) subjected through the digestive tract of cattle and to evaluate the germination of the seeds in feces of cattle. A 50 g of seed mixed with 150 g of mineral supplement offered to the cattle. Each cattle was considered as repetition. The bovine feces collected up to 60 hours after eating the seeds, where the seeds separated by sieves, using water, gloves procedure and tweezers. Later, they counted and divided into intact and swollen. For the germination test of the recovered seeds, 75 seeds per replicate were used (25 in natura, 25 intact and 25 swollen seeds, respectively). For the germination test in fecal plates, the bovine feces collected between 12 and 30 hours after eating the seeds. After 120 days, we evaluated the total amount of plants emerged within the study period (between 12 and 30 hours) and the average number of emerged plants per fecal signs. The results showed that cattle are facilitating the dispersion of butterfly pea, macrotyloma and perennial soybean, but not stylosanthes. The highest survival as the average number of germinated plants in fecal plates achieved by macrotyloma, followed by butterfly pea species and perennial soybean. The cattle were efficient in the pasture colonization process, due to the considerable dispersion of the seeds. This dispersion was not observed for seeds of stylosanthes.
Pages 7-12 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p1359
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Effects of drought stress and superabsorbent polymer on morpho-physiological and biochemical traits of Caper (Capparis spinosa L.)
Aminallah Bagherifard, Yousef Hamidoghli*, Mohammad Hasan Biglouei, Mehrorang Ghaedi
Department of Horticultural Science, University Campus 2, University of Guilan, Rasht, Iran
Department of Horticultural Science, Faculty of Agricultural Sciences, University of Guilan, Rasht, Iran
Department of Irrigation, Faculty of Agricultural Sciences, University of Guilan, Rasht, Iran
Department of Chemistry, Faculty of Sciences, University of Yasuj, Yasuj, Iran
Abstract
Capparis spinosa, commonly known as caper bush, is native to certain hostile growing conditions including sandy or gravelly soils, rocky hillsides, cliffs, stone walls and rock crevices in Mediterranean coastal regions. Caper plant is used for the prevention of soil erosion in sloppy areas. Synthetic superabsorbent polymer was developed as a soil conditioner to heighten plant establishment and growth in drought-prone growing area. During growing seasons of 2016-2017, the effects of soil amendment with the superabsorbent Polymer A200 in four levels (S1= 0, S2= 75, S3= 150 and S4= 225 g) were investigated for each caper plant, considering three levels of irrigation (I1=0, I2= One irrigation per month and I3= one irrigation every two months) on the physical properties of the soil as well as their physiological parameters (chlorophyll a, b and total chlorophyll, carotenoid, Tss, electrolyte leakage) and plant height, yield per hectare, WUE, Soil moister, RWC and leaf area of an established caper plant under drying conditions. Analyses of variance showed that the interaction effects of treatments were significant (p<0.01) in all the studied traits. The results showed that water stress significantly decreased the height of a plant, yield per hectare, WUE, Soil moister, RWC, leaf area, total Chlorophylla, Carotenoid and electrolyte leakage, whereas the application of superabsorbent polymer compensated for the negative effect of drought stress, especially in high rates of polymer application (150 g), where the maximum effect was attained for all the studied traits. These findings strongly suggested that the irrigation intervals of caper can lead to an increase in the application of the superabsorbent polymer.
Pages 13-20 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p1418
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Induction of seed coat darkening in common beans (Phaseolus vulgaris L.) and the association with cooking time after storage
Renata C. Alvares, Helton S. Pereira, Leonardo C. Melo, Phillip N. Miklas, Patrícia G. S. Melo*
Empresa Caraíba, Rodovia GO-174, Km 4,9, S/N-Fazenda Lagoinha, Rio Verde, GO, Brazil
Embrapa Arroz e Feijão, Rodovia GO-462, km 12, Santo Antônio de Goiás, GO, 75375-000, Brazil
USDA-ARS Research Geneticist. USDA-ARS 24106 N Bunn Rd. Prosser, WA 99350-8694 USA
Universidade Federal de Goiás, Rodovia GO-462, km 0, Campus Samambaia, Goiânia, GO, 74001-970, Brazil
Abstract
Carioca is the most important edible dry bean (Phaseolus vulgaris L.) grown in Brazil. It represents the largest dry bean market class in the world. The seed coat of carioca beans will darken under adverse harvest conditions and with the increasing of storage time. In general, darkened seeds are associated with older seeds that suffer from prolonged cooking times. A relatively new ‘slow darkening’ trait is available in carioca that delays seed coat darkening under storage. However, its effect on cooking time is unknown. The objective of this work was to evaluate two induction methods of seed coat darkening and to examine the effect of slow darkening trait on cooking time after storage. Lines derived from four segregating populations resulting from crossings between cultivar BRSMG Madrepérola with slow seed coat darkening, and the parents BRS Estilo, BRS Cometa, BRS Notável and BRS Sublime with normal darkening were evaluated. An experiment inlcuding 220 lines, 55 per population and the five parents, in a 15x15 triple lattice was conducted in the winter growing season in Brasilia. Seed coat darkening and cooking time traits were evaluated. Two methods for inducing seed coat darkening were compared: an accelerated aging test using UV light for 72 hours, and an extended storage for 90 days under ambient conditions. The correlation between the induction methods ranged from 0.77 to 0.85 for the different populations indicating either method could be used to discriminate lines with normal versus slow darkening trait. The percentage of light-colored grain lines was identified by both induction methods of seed coat darkening ranged from 75 to 85.7% in the populations. The genetic correlation between seed coat darkening and cooking time varied from -0.06 to -0.48, indicating that in some populations there is no significant genetic correlation between seed coat darkening and cooking time. Thus, light colored grains are not indicative of low cooking time, when they are considered genotypes with genetic variation for the seed coat darkening.
Pages 21-27 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p1500
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Meteorological conditions and their associations with the productive performance of wheat
Thomas Newton Martin*, José Eduardo Minussi, Jessica Deolinda Leivas Stecca, Giovani Mathias Burg, Marlo Bison Pinto
Department of Crop Science, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil
Abstract
This study aimed at assessing the effect of the photothermal quotient, meteorological variables and their effects on the grain production and yield of the wheat cultivars in terms of hectoliter mass in Santa Maria, Rio Grande do Sul state, Brazil. The experiments were carried out in the same experimental area in different years. Four experiments were performed in the experimental field during the agricultural years of 2013 (10 cultivars), 2014 (16 cultivars), 2015 (15 cultivars) and 2016 (15 cultivars) with the principal cultivars in the Rio Grande do Sul state, during each of these years. The meteorological factors (mean air temperature, solar radiation, insolation and accumulated precipitation) showed wide fluctuations over these years. They induced instability in the production. The grain yield and the hectoliter mass were compared in each of the agricultural years (Scott-Knott, α≤0.05) and are related in dispersion plots according to the climatic variables for the set of years and cultivars (regression analysis). The available solar radiation (number of sunshine hours), quality (photothermal quotient) and average air temperature were the determinant factors for wheat productivity. However, the hectoliter mass was influenced more by the effect of genetic variability, lack of precipitation during crop maturation, and photothermal quotient around the time of anthesis. Wheat crop investments can be expanded to maximize wheat grain yield when average cycle temperatures remain near 16.5 oC, high solar radiation and low rainfall. Better quality trains (hectoliter mass) will be obtained when smaller precipitations are observed at harvest and higher photothermal quotient.
Pages 28-35 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p1704
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Integrated management of Striga hermonthica and S. asiatica in sorghum: A review
Emmanuel Mrema*, Hussein Shimelis, Mark Laing, and Learnmore Mwadzingeni
University of KwaZulu-Natal, African Centre for Crop Improvement, Private Bag X01, Scottsville 3209, Pietermaritzburg, South Africa
Tanzania Agricultural Research Institute, Tumbi Center, P.O. BOX 306, Tabora, Tanzania
Abstract
Potential yield of sorghum [Sorghum biocolor (L.) Moench] in the semi-arid agro-ecologies of East Africa is curtailed by several biotic, abiotic and socio-economic constraints. Striga is one of the major biotic constraints that causes up to 90% yield losses in sorghum in the region. In these regions Striga hermonthica and S. asiatica, are widely distributed, and severely affecting sorghum production and productivity. Several Striga management strategies are available that can be integrated to synergistically combat the weed. The use of resistant sorghum genotypes that are compatible with Fusarium oxysporum f.sp. strigae (FOS), a biocontrol agent of Striga, together with host plant resistance could promote integrated Striga management (ISM). This strategy is yet to be explored in most SSA countries where sorghum serves as a staple food crop for millions of households. This review discusses the management options available to control S. hermonthica and S. asiatica in sorghum. Breeding sorghum for Striga resistance and compatibility to FOS are highlighted as key components of integrated Striga management.
Pages 36-45 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p1749
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Resistance of Arabica coffee cultivars to leaf wounds and Pseudomonas syringae under field conditions
Lucas Eduardo Fernandes, Willian Gabriel dos Santos, Fernando Cesar Carducci, Inês Cristina de Batista Fonseca, Lucas Mateus Rivero Rodrigues, Luís Otávio Saggion Beriam, Carlos Theodoro Motta Pereira, Luciana Harumi Shigueoka, Gustavo Hiroshi Sera*
Instituto Agronômico do Paraná (IAPAR), Plant Breeding Department, Rodovia Celso Garcia Cid, km 375, 86047-902, Londrina-PR, Brazil
Universidade Estadual de Londrina (UEL), Agronomy Department, Rodovia Celso Garcia Cid, km 380, 86057-970, Londrina-PR, Brazil
Instituto Agronômico (IAC) Centro de Café Alcides Carvalho, CP 28, CEP 13001-970, Campinas-SP, Brazil
Instituto Biológico, CP 70, CEP 13012-970, Campinas-SP, Brazil
Abstract
The aims of this study were: (a) to evaluate the resistance of coffee cultivars to Pseudomonas syringae (PS); (b) verify if there are coffee genotypes that present less wounds on the leaves; (c) to study the correlation between amount of wounds and PS severity. The field trial was installed in April 2014 at the IAPAR’s experimental station (Londrina, Paraná, Brazil). 18 Arabica coffee cultivars were evaluated. The cultivars Mundo Novo IAC 376-4 and Catuaí Vermelho IAC 81 were the susceptible controls and IPR 102 was the resistant control. After 32 months of planting the field trial, resistance to PS was evaluated in December 2016. The evaluation of the PS severity was carried out under conditions of natural infections of P. syringae pv. garcae and P. syringae pv. tabaci based on the symptoms, using a grading scale from 1 to 5. The number of wounds on the leaves of the eight cultivars were counted. The results showed that IPR 102 was resistant to Pseudomonas syringae, whereas IPR 99, Arara, IPR 107, Acauã, Sabiá, Catucaiam 24137, Japy and Catuaí Vermelho IAC 81 were susceptible. Mundo Novo and Catucaí Amarelo 2SL were more susceptible than Catuaí Vermelho. IPR 106, Japiam, Catiguá MG 2, Catiguá MG 1 and IBC Palma 2 showed moderate resistance, while IPR 103 and Catucaiam 2015479 were moderately susceptible. The cultivars IPR 102 and IPR 106 presented resistance to wounding because they had lower wounds than other cultivars. Increased leaf wounds was associated with increased P. syringae severity.
Pages 46-50 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p1781
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Root traits and carbon input by sweet sorghum genotypes differs in two climatic conditions
Ibrahim. A. M. Ahmed, Ibrahim Ortaş*, Celal Yucel, Abdullah Oktem, Derya Yucel, Md Toufiq Iqbal*
Department of Soil Science and Plant Nutrition, University of Cukurova, Adana, Turkey
Eastern Mediterranean Agriculture Research Institute, Adana, Turkey
University of Harran, Department of Field Crops, Faculty of Agriculture, SanliSanlıurfa, Turkey
Department of Agronomy and Agricultural Extension, University of Rajshahi, Rajshahi 6205, Bangladesh
Abstract
Response of sweet sorghum [Sorghum bicolor (L.) Moench] root traits and carbon (C) input under two different climatic condition is not well understood. The aims of this study were to characterize and compare root biomass and root traits of several sweet sorghum genotypes at field condition and to estimate their C input to into soil. Roots and shoots were analyzed for C concentration and CO2 was calculated. Root samples were collected through monolith root sampling techniques. Root morphological characteristics like root surface area and root volume were differed between locations as well as locations × genotypes interactions. Root surface area varies from 423,800 to 887,800 m2 ha-1 in Mediterranean soil and 339,100 to 579,600 m2ha-1 for Harran soil. All sweet sorghum genotypes inputs root and shoot C as well as CO2 higher in Mediterranean than Harran soil. Root C input varies from 140 to 386 Mg ha-1 in Mediterranean soil and 112 to 224 Mg ha-1 for Harran soil. A greater diversity of root traits was found on several sweet sorghum genotypes irrespective to plant biomass C inputs into the soil. However, compared to several sweet sorghum genotypes, their lower C input to soil needs to be recognized to ensure a balanced C budget. This study concluded that several sweet sorghum genotypes can be a good source of soil C sequestration under different climatic conditions of Turkey.
51-63 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p1782
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Simulation of scenarios considering different stump and pre-bucking disc heights in mechanized timber harvesting operations in Pinus spp. stands after the fourth thinning
Gustavo Silva Oliveira*, Philipe Ricardo Casemiro Soares, Jean Alberto Sampietro, Maycon Thuan Saturnino da Silva, Marcos Felipe Nicoletti, Chaiane Rodrigues Schneider, Thiago Floriani Stepka, Julio Peretti da Silva
Department of Forestry Sciences, Federal University of Paraná – UFPR, Curitiba, Paraná, Brazil
Department of Forest Engineering, University of the State of Santa Catarina – UDESC, Lages, Santa Catarina, Brazil
Abstract
This study aimed to quantify scenarios, considering different stump and pre-bucking disc heights, in order to search for alternatives to optimize the mechanized timber harvesting process in a Pinus spp. forest. In this way, the simulation of six scenarios was carried out after the fourth thinning. The situation defined by the company in its planning was considered and applied to scenario 1 (S1), with stump heights and pre-bucking disc heights of up to 15 cm and 10 cm, respectively. The scenario 2 (S2) included the real situation, that is, the measurements made in sample units installed on the field, scenario 3 (S3) included stump heights of 10 cm and pre-bucking disc heights of 5 cm and, in the other scenarios (S4, S5 and S6), stump and pre-bucking disc heights with values higher than the ones specified by the company were included. To that end, taper functions were used to quantify the assortments and the economic returns for each scenario. Results showed that scenario 3 presented the highest economic gain (5434.27 USD ha-1) followed by scenario 2 (5431.97 USD ha-1), surpassing the production expectations (S1). Therefore, the company must seek to improve and optimize the mechanized harvesting process by increasing investments for improvements in the planning of the operations, establishing measures throughout the production process and training the employees. These changes can reduce the non-conformities, expand revenues and result in better use of natural resources.
Pages 64-70 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p1843
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Can silicon (Si) influence growth, physiology and postharvest quality of lettuce?
Hozano de Souza Lemos Neto*, Marcelo de Almeida Guimarães, Italo Marlone Gomes Sampaio, Janiquelle da Silva Rabelo, Caris dos Santos Viana, Rosilene Oliveira Mesquita
Federal University of Ceará, Center for Agrarian Sciences, Departament of Plant Science. 60356-001, Fortaleza, Ceará, Brazil
Federal Rural University of Amazonia, Institute of Agrarian Sciences, Department of Soils, Belém, Pará, Brazil
Abstract
Although it is not considered an essential element for plants, silicon (Si) provides benefits for several species, especially grasses, such as increase in yield and resistance to pests and diseases, reducing the effects of salt and water stress, among others. The aim of this study was to evaluate the effect of silicon on the performance of lettuce in hydroponic system. The experiment was carried out in a completely randomized design, with five doses of silicon (0, 2, 4, 6, 8 mM) in the nutrient solution. Shoot fresh and dry mass, gas exchanges, photosynthetic pigments and post-harvest were evaluated. It was observed that from the dose of 2 mM, there was a reduction in most variables. The dose of 0.4 mM [(-0.572)/(2*-0.7055)] provided a greater increase in shoot fresh mass. The highest photosynthetic rate was at the dose of 3.19 mM. Soluble solids, titratable acidity and pH were higher at the 4 mM dose. Silicon provides better lettuce production, with a dose of 0.4 mM allowing a greater shoot fresh mass, being the most indicated for lettuce cultivation in hydroponic system.
Pages 71-77 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p1848
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Phosphorus fertilization with enhanced efficiency in soybean and corn crops
Luiz A. Zanão Jr, Orivaldo Arf, Roberto dos A. Reis Jr, Natalia Pereira*
Agronomic Institute of Paraná, Soils Area, Santa Tereza do Oeste, Paraná, Brazil
São Paulo State University (UNESP), Department of Plant Science, Food Technology and Social Economy, Ilha Solteira, State of São Paulo, Brazil
Wirstchat Polímeros do Brasil, Londrina, PR, Brazil
Western Paraná State University, Department of Agricultural Engineering, Cascavel, Brazil
Abstract
Due to the low natural availability of phosphorus (P) in tropical soils and the plants’ need for P, the use of phosphorus fertilizers of increased efficiency is an important tool for achieving high yields. The aims of this study were to evaluate plant growth, foliar P content and yield of soybean and corn crops in different seasons and places, in response to P rates and sources. The monoammonium phosphate (MAP) and Policote coated MAP (Policote+MAP) were used as sources of P. Field experiments were carried out comparing MAP performance in relation to Policote coated MAP (MAP+Policote), an additive based on water soluble polymers. Experiments formed by P sources (MAP including 11% N, 52% P2O5 and MAP+Policote including 10% N, 49% P2O5) and rates were carried out in soybean and corn crops in different dates and sites. In the soybean crop, the factorial (2x4) +1 was used, being two sources, MAP and MAP+Policote, and four rates of P (30, 60, 90 and 120 kg ha-1 of P2O5), besides the control, while in the corn crop a factorial (2x5) was used, being two sources and five rates of P (0, 40, 80, 120 and 160 kg ha-1 of P2O5). Phosphorus fertilization increased soybean and corn plant heights and yields in different seasons and places. Soybean and corn yield and agronomic phosphorus use efficiency were higher with Policote coated phosphorus fertilizer than with conventional phosphorus fertilizer. Policote coated phosphorus fertilizer can be used as an enhanced efficiency fertilizer because it increased soybean and corn yields in different seasons and places.
Pages 78-84 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p1862
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Mixed production of Alexandergrass and sorghum under nitrogen fertilization and grazing intensities
André Brugnara Soares, Marcieli Maccari, Carine Lisete Glienke, Tangriani Simioni Assmann, Marcos Antonio de Bortolli, Denise Adelaide Gomes Elejalde, Regis Luis Missio
Technological Federal University of Paraná (UTFPR), Brazil
West Santa Catarina University (UNOESC), Brazil
Federal University of Santa Catarina (UFSC), Brazil
Abstract
Annual pasture species are used in southern Brazil to supply forage in the fall and spring when major forage species have their productivity diminished. Forage sorghum (Sorghum bicolor, (L.) Moench) is a suitable option that has been adopted by farmers due to its high quality as forage. It has been observed that in areas where forage sorghum is cultivated, alexandergrass (Urochloa plantaginea) usually appear as spontaneous specie. The aim of this study was to observe the effect of two grazing intensities (30 and 60 cm of sward height) and two nitrogen fertilization levels (0 and 200 kg N ha-1) on the quantity (forage mass), quality (CP, ADF, NDF, Lignin, Hemicellulose, Cellulose) and morphological components (stem, leaves, senesced material) of sorghum-alexandergrass mixed pasture grazed by beef cattle. Treatments were arranged in a completed randomized block design with three replications in a 2 x 2 factorial scheme. Forage mass was increased during the evaluation period. In the first period, production was 4,022 kg and it reached 5,233kg DM ha-1 in the third period. Treatments did not affect AG-sorghum mixed pasture botanical profile or quality. It was observed that Sorghum lowered its contribution from 63.4% in the first evaluation period to 21.5% in the third. In contrast, Alexandregrass (AG), contribution increased from 17.9 to 52.7% throughout the evaluation periods. Therefore, the addition of Alexandergrass to a planted sorghum pasture is encouraged because it can extend the grazing period into the fall by prolonging the pasture favorable sward structure and nutritive value.
Pages 85-91 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p1891
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Boron fertilization affects the physiological quality of soybean seeds, conventional and transgenic
Ivana da Silva Gomes, Cleiton Gredson Sabin Benett*, Ricardo Caldas Xavier, Katiane Santiago Silva Benett, Érica Fernandes Leão-Araújo, Anderson Rodrigo da Silva, Ademilson Coneglian
State University of Goias, Ipameri Campus, Ipameri, Goias, Brazil (Universidade Estadual de Goiás, Campus Ipameri, Goiás, Brasil)
Goiano Federal Institute, Urutai Campus, Urutai, Goias, Brazil (Instituto Federal Goiano, Campus Urutaí, Goiás, Brasil)
Abstract
High physiological quality soybean seeds are essential for a successful production, because they promote optimal plant density in the field. The objective of this work was to evaluate the effect of boron doses applied at different phenological stages of two soybean varieties on the physiological quality of the seeds. Two field experiments were carried out, one with each variety of soybean, conventional and transgenic. Five doses for boron were applied to the soil as boric acid (17%): 0, 1.0, 2.0, 3.0 and 4.0 kg ha-1, at three phenological stages (V6, V9 e R1). In R8 stage the seeds are harvested and then tested for physiological quality, through the tests of Germination, germination first count, germination speed index, accelerated aging and electrical conductivity. For the conventional variety, the boron doses promoted a quadratic effect on variables when the boron was applied near the reproductive stages. For the transgenic variety, the first-degree polynomial model presented the best fit, meaning that the higher the boron dose the better the physiological quality. The optimal boron application stage for producing high vigor seeds was R1 for both varieties. Four (4.0) kg ha-1 of boric acid is recommended for both varieties to produce high quality seeds.
Pages 92-97 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p1894
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Exogenous salicylic acid modifies gas exchange and biomass production of Mentha x piperita L.
Fabrício Custódio de Moura Gonçalves*, Nathália de Souza Parreiras, Felipe Girotto Campos, Luís Paulo Benetti Mantoan, Carmen Sílvia Fernandes Boaro
Universidade Estadual Paulista, Faculdade de Ciências Agronômicas, Botucatu, SP, Brasil
Universidade Estadual Paulista, Instituto de Biociências, Botucatu, SP, Brasil
Abstract
Peppermint (Mentha x piperita L.) is a medicinal plant that produces an essential oil used as an additive in food and pharmaceutical formulations. Salicylic acid is a phenolic compound widely distributed throughout the plant kingdom, being able to modify plant physiological and metabolic responses. The objective of this study was to evaluate the effects of the application of salicylic acid on the production of biomass, pigments, as well as gas exchange of peppermint plants. For this purpose, a completely randomized design composed of four replications was applied. Pigment evaluations were carried out in a 4x4 factorial scheme, consisting of the application treatments: 0 (control), 75, 150, and 225 mg L-1 of salicylic acid and four harvest periods. Gas exchange and physiological growth rates were evaluated in a 4x3 factorial scheme. Data were submitted to analysis of variance and regression. The application of salicylic acid increased CO2 assimilation and use, stomatal conductance, water use efficiency, and transpiration, which in turn, resulted in increased height, and dry stem and root mass production. It is concluded that the application of salicylic acid influences the primary metabolism, increasing gas exchange and biomass production of peppermint plants.
Pages 98-107 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p1900
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Response of bermudagrass to enhanced-efficiency fertilizers, application strategies and release under tropical conditions
Bernardo Melo Montes Nogueira Borges*, Fernanda Ribeiro Peixoto, Marilena de Melo Braga, Barbara de Brito Brunozzi, Maria Lucia Silveira, Edson Luiz Mendes Coutinho
São Paulo State University (Unesp), Campus Jaboticabal, Dep. of Soil Science, Via de Acesso Prof. Paulo Donato Castellane s/n, 14884-900, Jaboticabal, SP, Brasil
University of Florida, Range Cattle Research and Education Center, Ona, FL, USA, 33865.
Abstract
Nitrogen fertilization is an important input for crop yield; however, it can result in detrimental environmental effects due to low use efficiency of regular N sources. This study evaluated the effects of N fertilizers and application strategies (single vs. split application) on bermudagrass (Cynodon spp.) responses and release pattern and rate in controlled and field incubations. The bermudagrass study was arranged in a two-way factorial scheme of 6 N fertilizers, urea, Polymer Coated Urea (PCU), PCU-6 (6 months), PCU-4 (4 months), PCU-2 (2 months) and urea + urease inhibitor (U-NBPT) applied as a single (400 kg N ha-1 yr-1) or two split applications of 200 kg N ha-1 (400 kg N ha-1 yr-1). The controlled experiment was a two-way factorial of PCU-6, PCU-4, PCU-2 and 15, 45 and 90% water hold capacity (WHC), sampling period of 170 days, the field incubation used the same sources sampled up to 220 days. Enhanced-efficiency fertilizers (EEF) increased herbage accumulation (HA) by 1.3 Mg ha-1 compared to untreated urea, on average. Nitrogen use efficiency (NUE) was greater for EEFs (44%) than urea (36%). Results showed that increased soil moisture inferred positive responses in release pattern and a minimum of 45% WHC was necessary for optimum release. Fertilizers at field conditions resulted in an earlier release than expected, ~20 days.
Pages 108-115 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p1929
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Morphological and physiological responses to drought stress in a set of Brazilian traditional upland rice varieties in post-anthesis stage
Leandro Martins Ferreira*, Orlando Carlos Huertas Tavares, Cristiana Maia de Oliveira¬, Sonia Regina de Souza, Manlio Silvestre Fernandes, Leandro Azevedo Santos
Universidade Federal Rural do Rio de Janeiro, Departamento de Solos, Instituto de Agronomia, Rodovia BR 465 Km 7 Seropédica-RJ 23890-000, Brazil
Universidade Federal Rural do Rio de Janeiro, Departamento de Fitotecnia, Instituto de Agronomia, Rodovia BR 465 Km 7 Seropédica RJ 23890-000, Brazil.
Universidade Federal Rural do Rio de Janeiro, Departamento de Química, Instituto de Ciências Exatas, Rodovia BR 465 Km 7 Seropédica-RJ 23890-000, Brazil
Abstract
Among the abiotic stresses that can affect the growth and development of the crop, drought is considered one of the main factors that can reduce the global food production. The goal of this study was to analyze the effect of drought stress on several morphological and physiological parameters in ten traditional upland rice varieties. The experimental design set up in a factorial scheme 10 x 2 (varieties x treatments) with four replicates under greenhouse conditions. At the start of the reproductive stage, rice varieties were submitted to control and drought conditions during 30 days and evaluated for physiological and morphological parameters. Rice varieties were considered as tolerant and susceptible to drought stress based on the classification proposed by five different stress tolerance indices (SSI, TOL, SSSI, DYI and DTE). The results suggest that the adopted indices associated with multivariate analysis from the parameters analyzed are efficient to discriminate between tolerant and susceptible rice varieties to the drought stress. Catetão and Piauí were considered as the most tolerant, while Quebra Cacho and Mira were the most susceptible. The analysis of morphological and physiological parameters through multivariate analyses revealed as an important tool to assist breeders in the identification of tolerant and susceptible varieties and to characterize how the varieties alter their metabolism to withstand the drought stress.
Pages 116-123 | Full Text PDF| Supplementary Data PDF| doi: 10.21475/ajcs.20.14.01.p1944
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Impact of mixing treated industrial water with olive mill wastewater on vetch (Vicia sativa L.) germination and early seedling growth
Naji K. Al-Mefleh*, Maher J. Tadros, Jalal A. Al-tabbal
Department of Natural Resources, Jordan University of Science and Technology, P.O. Box 3030, Irbid, Jordan
Department of Nutrition and Food Processing, Al-Huson University College, Al-Balqa Applied University, Irbid, Jordan
Abstract
Vetch is a forage crop that is widely grown in high rainfall areas in Jordan for forage production and grazing. Growing vetch species out of the season will need irrigation, which is very expensive. In here, we propose application of wastewater or olive mill wastewater as alternative to the fresh water. An experiment was carried out to evaluate the effect of diluting the industrial water (IND) with olive mill wastewater (OMWW) on the vetch germination (GR) and early seedling growth under controlled conditions. The water treatments consisted of T1 (pure IND100%), T2 (mix of IND75% + OMWW25%), T3 (IND50% + OMWW50%), T4 (IND25% + OMWW75%) and T5 (pure OMWW100%) and tap water (control). This experiment was designed in a CRD with three replications for each treatment. Several measurements on the morphological and biochemical analysis were taken during this study such as seed germination (GR), as well as the seedlings fresh weight of shoot (FWS), dry weight of shoot (DWS), fresh weight of shoot (FWR), dry weight of root (DWR), shoot length (SL), root length (RL) and the ratios of DWS/DWR and SL/RL. The water treatments had a significant influence on data taken, in which the highest mean values of morphological characteristics were obtained under the T1, while the lowest were obtained under the T5 due to high phenols concentrations. The OMWW treatment showed an adverse effect on GR, DWS, DWR, SL, and RL due to low pH values (4.5) and high phenols concentration (1700 mg/L). In contrast, the industrial water showed low to moderate effect on the vetch seed germination. The means of DWS and DWR under T3 and T4 were not significantly different from each other but were different comparing with control. It is recommended that the use of a mixture of OMWW and the Industrial water will have a positive effect on Vetch growth.
Pages 124-132 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p1969
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Leaf composition and productivity of yellow passion fruit (Passiflora edulis Sims. “Guinezinho”) in soil with bovine biofertilizer and nitrogen
Adriana Araújo Diniz, Lourival Ferreira Cavalcante, Antônio Gustavo de Luna Souto*, Eudes de Almeida Cardoso, Patrícia Carneiro Souto, Rejane Maria Nunes Mendonça, Nildo da Silva Dias
State University of Maranhão, Departament of Agronomy, Balsas city, Maranhão State, Brazil
Federal University of Paraíba, Department of Soil and Rural Engineering, Areia city, Paraíba State, Brazil
Federal University of Paraíba, Departament of Plant Science, Areia city, Paraíba State, Brazil
Federal Rural Semiarid University, Agricultural Science Center, Mossoró city, Rio Grande do Norte State, Brazil
Federal University of Campina Grande, Forest Engineering Academic Unit, Patos city, Paraíba State, Brazil
Abstract
The use of alternative inputs, derived from the fermentation of fresh organic matter, exerts significant importance in the pasiculture in partial substitution to synthetic commercial fertilizers. An experiment was conducted in the period from 2013 to 2014 to evaluate the effects of bovine biofertilizer and nitrogen, on leaf mineral composition of macronutrients, micronutrients and sodium and productivity of yellow passion fruit. The treatments were arranged in randomized blocks with three replicates and nine plants per plot. We arranged a 5 × 2 factorial scheme, referring to the bovine biofertilizer applied to the soil in the liquid form (B) in the proportions in water (W) of 0 (0B + 4W); 25 (1B + 3W); 50 (2B + 2W); 75 (3B + 1W) and 100% (4B + 0W), in the soil without and with nitrogen. The seedlings were developed from fruit seeds with large size, oblique shape and mass. The bovine biofertilizer was applied at 4 L plant-1 in water, 7 days before and 90 days after transplanting of 50-day-old seedlings. The nitrogen was applied to the relevant plots every 30 days after transplantation of the seedlings until the end of the experiment. The resulrs showed that plants were adequately supplied in N, Mg, S, B, Cu and Zn, but deficient in P, K, Ca, Cu, Fe and Mn at the beginning of flowering. The highest fruit production of 30.75 t ha 1 was obtained from the plants in soil with 100% of bovine biofertilizer and with nitrogen. Due to the higher fruit productivity in plants with biofertilizer bovine + nitrogen, compared to those treated with only bovine biofertilizer, it is verified that the organic input does not substitute the nitrogen for the cultivation of the yellow passion fruit.
Pages 133-139 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p2013
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Yield potential of green maize from partially inbred lines in top crosses
Caique Machado e Silva, Willame dos Santos Candido*, Pedro Henrique Sousa Almeida, Maraiza Lima Costa, Bruna Elaine de Almeida Silva, Jefferson Fernando Naves Pinto, and Edésio Fialho dos Reis
Universidade Federal de Goiás – Regional Jataí, BR 364 km 194 n° 3800, zip code75800-000, Jataí municipality, Goiás State, Brazil
Abstract
Selecting potential progenies in early inbred generations is an essential step towards the success of breeding programs. Given this, the use of top crosses assists breeders in selecting progenies to generate lines with the potential for hybrid yield. Thus, the purpose of this study was to assess the behavior of partially inbred progenies (S1) of maize with potential for green maize yield in top crosses and to evaluate the hybrid performance. Seventy-five top cross hybrids were generated from the cross between 75 S1 progenies and the F2 generation of the hybrid AG 1051. The 75 hybrids, the male tester (F2 generation of the hybrid AG 1051 as a broad genetic base tester), and the hybrid AG 1051 were sown in a block design with four replicates. The following traits were evaluated: husked ear yield; commercial ear yield; flowering; plant height; strawing; mean weight of grain mass in green maize stage; tassel branch number; ear row number; ear length; and ear diameter. The analysis of variance was performed estimating the general combining ability, and, from the means, the Scott & Knott test was conducted. The top cross hybrids that were prominent for commercial ear yield were those composed of partially inbred progenies 19, 48, 6, 28, and 42 with high GCA, suggesting a potential for the production of open pollination population or synthetic production as well.
Pages 140-149 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p2020
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Evaluation of weed changes according to different fertilization management systems, through phytosociological analyzes in lettuce and carrot
Elis Marina de Freitas, Valter Carvalho de Andrade Júnior, Evander Alves Ferreira, Danielle Cristina Fonseca Santos Grazziotti, Amanda Gonçalves Guimarães*, Fernando Augusto da Silveira, Lidiane Rodrigues da Silva, Andreia Marcilane Aker
Federal University of Jequitinhonha e Mucuri Valleys, Campus JK - Rodovia MGT 367 - Km 583, nº 5000, Alto da Jacuba- CEP 39100-000, Diamantina/MG, Brazil
Lavras Federal University, Campus Universitário, Caixa Postal 3037, CEP 37200-000, Lavras/MG, Brazil
Federal University of Minas Gerais, Campus Regional de Montes Claros, Avenida Universitária, 1000, Universitário, CEP: 39404-547, Montes Claros/MG, Brazil
Vicosa Federal University, Campus Viçosa, Avenida Peter Henry Rolfs, s/n, CEP: 36570-900, Viçosa/MG, Brazil
Abstract
The population dynamics of weeds due to different fertilization management systems is essential in the agricultural areas for the understanding of their interference and possible damages. The objective of this study was to evaluate the influence of different fertilization management systems on the weed community through phytosociological analyzes in lettuce and carrot crops grown in succession. The experimental design was a randomized block design, with eight treatments and four replications in each plant, following the same experimental layout. The treatments, referring to different management of fertilization were: Conventional; With Weeds; No Weeds; Compound; Crotalaria; Crotalaria more Compound; Lab-Lab and Lab-Lab + Compound. During cultivataion of lettuce and carrot, we collected more than 3,000 weed specimens, representing 25 species distributed in 11 families, 88% dicotyledonous and 22% monocotyledonous. The weed families with the highest value of importance in all stages of collection were Asteraceae, Brassicaceae and Poaceae. The most representative species in the area were Eleusine indica, Cyperus rotundus L., Galinsoga parviflora, Richardia brasiliensis, Oxalis latifolia, Cynodon dactylon and Conyza canadensis. The different forms of fertilization and use of cover crops were able to promote changes in the weed community and decrease in the population density during the experimental period. The treatments contributed to reduce the daily amplitudes of thermal and water changes and the incidence of sunlight on the surface layer of the soil, delaying the emergence of these weeds and contributing to other soil benefits inherent to the use of each type of fertilization.
Pages 150-160 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p2037
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Growth performance of Mission and Kyasuwa grasses (Pennisetum sp.) under different NPK ratios as potential slope cover
Afaff Emhemed Ettbeb, Zulfahmi Ali Rahman*, Wan Mohd Razi Idris, Jumaat Adam, Sahibini Abd Rahim, Tukimat Lihan, Siti Norhafizah Ahmad Tarmidzi, Nurul Atiqah Mohd Azlam
Center of Earth Science and Environment, Faculty of Science and Technology, University Kebangsaan Malaysia, 43600 Bangi, MALAYSIA
Environmental Science Program, Faculty of Science and Natural Resources, Universiti Malaysia Sabah, Jalan UMS, 88400 Kota Kinabalu Sabah, MALAYSIA
Abstract
The Mission (Pennisetum polystachio) and Kyasuwa (Pennisetum pedicellatum) grasses are common perennial plants found in tropical regions that tolerate low nutrient soils, easily spread by wind and colonization of new areas. It is a great challenge for researchers to select plant species in terms of their performance for vegetation cover to minimize the sloppy soil erosion. Therefore, this study aimed to evaluate the growth performance of selected Pennisetum sp. namely P. pedicellatum (PPd) and P. polystachio (PPl) under different NPK ratio. The studied species were treated with three different treatments, F1, F2 and NF under greenhouse conditions. Hydroseeding technique was adopted for germination of the selected species in the polybags and periodically monitored for a duration of six months. Parameters measured for the growth performance of the studied species were based on plant height, total biomass and chlorophyll content. After application of the treatment F1 and F2, the soil pH changed to slightly acidic (pH 5.45) while organic content of soil was slightly increased from 3.2% to 3.9%. A similar result was also found in N and P nutrient availability of the soil. Meanwhile, available K decreased from 29.76 mg/kg to 28.41mg/kg (F1) and 23.83 mg/kg (F2) for PPl species. This trend was also observed by the PPd species. The PPd species with F1 and F2 treatments showed higher value of plant height if compared to that of PPl species. In terms of total biomass and chlorophyll content, PPl species treated with both treatments showed higher value than PPd species. Species treated with F1 showed higher value in all growth performance variables (height, dry biomass and chlorophyll content), if compared to that of F2 and NF treatments. These findings discovered Pennisetum polystatchion (PPl species) as a potential biological material that can be used as a slope vegetation cover.
Pages 161-171 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p2057
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Selection of top cross hybrids for green maize yield via REML/Blup method
Willame dos Santos Candido, Caique Machado e Silva, Maraiza Lima Costa, Bruna Elaine de Almeida Silva, Pedro Henrique Sousa Almeida, Igor Ferreira Coelho, and Edésio Fialho dos Reis
Niversidade Federal de Goiás – Regional Jataí, BR 364 km 194 n° 3800, zip code 75800-000 municipality of Jataí, State of Goiás, Brazil
Universidade Federal de Viçosa, Av. Peter Henry Rolfs, s/n, Centro, zip code 36570-900 municipality of Viçosa, State of Minas Gerais, Brazil
Abstract
The purpose of this study was to select top cross hybrids of green maize for yield, derived from partially inbred S1 lines based on genetic values using the REML/Blup method, and to estimate important genetic parameters for green maize breeding programs. The experiment was conducted in an experimental area located between 17º53´ S and 52º43´ W, 680 m altitude. The evaluation of 75 top cross hybrids was performed in a randomized block design with four replicates. A sample of five plants/ears was used in each plot to evaluate grain mass trait (MASS). For commercial ear yield trait (CEYIELD), evaluations were carried out for the total number of plants per plot. Hybrids were selected via BLUP procedures using the Selegen-REML/Blup program. Based on the Restricted Maximum Likelihood (REML), we estimated the coefficients of genetic and residual variation and components of variance, by which a genetic variability between the top cross hybrids was observed. This shows the possibility of successful selection for the traits under evaluation. The estimated accuracy for the selection of top cross hybrids was 0.81 for commercial ear yield and 0.64 for grain mass, pointing to high and moderate precision levels for CEYIELD and MASS traits, respectively, corroborating the possibility of success in selecting top cross hybrids based on the CEYIELD trait. The predicted genetic gain from the selection was 20.12%, for CEYIELD, and 6.10%, for MASS. Therefore, the REML/Blup statistical tool was efficient in selecting top cross hybrids of green maize, providing significant genetic gains for the traits under evaluation. There was evidence that hybrids 19 and 48 were distinguished from others because of the high genetic effects obtained for the commercial ear yield and grain mass weight.
Pages 172-178 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p2061
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Potassic and nitrogen fertilization in a modern hybrid of sorghum for biomass production cultivated in an Oxisol
Franciele de Freitas Silva, Thomas Jefferson Cavalcante, Kassia de Paula Barbosa, Gustavo Castoldi*, Mariângela Brito Freiberger, Fabiano Guimarães Silva
Goiano Federal Institute. Rio Verde, GO, Brazil
Abstract
Biomass sorghum [Sorghum bicolor (L.)] is a promising option for the supply of dedicated biomass for energy cogeneration in Brazil. However, it is still necessary to better understand gaps around the nutrient requirement and fertilization management, especially for modern materials. The aim of this study was to evaluate the effect of nitrogen (N) and potassium (K) doses on dry matter (DM) and nutrient accumulation in a modern hybrid of biomass sorghum cultivated in an Oxisol. For that, two separate trials were carried out with the hybrid Palo Alto 2562, grown in 2015/16 summer season in the central-western region of Brazil. Both trials were carried out in a randomized block design with four replicates and five doses: 0, 70, 140, 210 and 280 kg ha-1 (of N or K). The hybrid Palo Alto 2562 responded positively to N fertilization. The DM production and N accumulation hybrid of Palo Alto 2562 was increased as N fertilization added, reaching, respectively, values of 24.6 Mg ha-1 and 206 kg ha-1 at dose of 280 kg ha-1 N. Also, in order to avoid depletion of N levels in the soil we required a fertilization of at least 140 kg ha-1 N. The Palo Alto 2562 hybrid has a high absorption capacity of K, which is the most absorbed nutrient by the plant, reaching values of 316 kg ha-1. However, in this study due to high levels of K in the soil and high K saturation in CEC, the K fertilization may be not necessary to produce sorghum biomass.
Pages 179-186 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p2163
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Yield index of crops grown under no-tillage after superficial application of micronized liming materials (MLM) on the soil
Jessica Alves Nogaroli*, Adriel Ferreira da Fonseca
State University of Ponta Grossa, Carlos Cavalcanti avenue, Ponta Grossa, Paraná, Brazil
Abstract
The development of strategies for the control of soil acidity in production systems using micronized liming material (MLM) could be a strategy in areas under no-till (NT) to produce high crops yield. The micronized liming material (MLM) have faster reaction on the soil surface even without incorporation to the soil. The experimental design used was completely randomized blocks in split-plot with four replications in a Typic Distrudept under NT treated with MLM. In the main plots the dolomitic limestone (DL) and MLM (granulated micronized calcite (GMC); granulated micronized dolomite (GMD) and carbonated suspension (CS) were studied. In the subplots, four doses of liming materials aiming were assigned to increase soil base saturation (BS) to 50, 70 and 90 %, besides of control treatment. We measured the relative yield (RY), relative yield change (RYC) and production efficiency (PE) of wheat, soybean, black oat and maize during four consecutive years (2012 to 2016). The MLM presented major RY and PE along experimental period than DL. Besides, the major relative yield change of MLM refers to lower responsiveness, major residual effect as well as major or maintenance crops yield. Better results were found in the BS dose aiming to 61 % for all the liming materials studied for production efficiency (PE), showing that it is the adequate BS for control of acidity in Typic Distrudept.
Pages 187-195 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p2199
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Reaction of Avena spp. to different concentration levels of Meloidogyne javanica and M. incognita inoculum
Cláudia Fernanda Carraro-Lemes*, Carolina Cardoso Deuner, Simone Meredith Scheffer-Basso, Valéria Cecília Ghissi Mazzetti, Jaqueline Huzar Novakowiski
University of Passo Fundo, Passo Fundo, RS, Brazil
Abstract
The objective of this study was to evaluate the resistance reaction of Avena spp. after inoculation of different concentrations of juveniles and eggs of M. javanica and M. incognita. Ten oat genotypes (Avena sativa: UPFPS Farroupilha, UPFA Ouro, IPR Afrodite, AF1345 Ucraniana; A. strigosa: Agro Quaraí, Agro Esteio, Embrapa 139, Iapar 61 Ibiporã, UPFA 21 Moreninha, AF 12202) were evaluated in bioassays for resistance against the root-knot nematodes, Meloidogyne javanica and M. incognita. Susceptible (Solanum lycopersicum and Glycine max) and resistant (Crotalaria spectabilis) species were used as control treatments. Depending on the inoculum level, the oats showed a different response to nematodes. All genotypes of oats were resistant to M. javanica when a high inoculum level (5,000 eggs and J2 per plant) was used but under low inoculum level (1,500 eggs and J2 per plant), AF 12202, Iapar 61 Ibiporã, Agro Esteio and Agro Quaraí were susceptible. All genotypes of oats were resistant to the inoculation of 2,900 eggs and J2 of M. incognita, except for ‘Iapar 61’ that showed susceptibility in this concentration. At lower inoculum level (1,500 eggs and J2) Agro Quaraí, Agro Esteio and Iapar 61 Ibiporã were susceptible. The reaction of oats to M. javanica and M. incognita depends on the inoculum level. The resistance reaction at low inoculum density of A. sativa ‘AF 1345 Ucraniana’ and ‘IPR Afrodite’ allows its use in breeding programs in oats and suggests the possibility of management tool in areas infested with both root-knot nematode species.
Pages 196-203 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p1960
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Stochastic modeling of reference evapotranspiration in arid and semi-arid zones
Janilson Pinheiro de Assis, Roberto Pequeno de Sousa, Walter Rodrigues Martins, Paulo César Ferreira Linhares, Eudes de Almeida Cardoso, José Aluísio de Araújo Paula, Mateus de Freitas Almeida dos Santos, Isadora Lorrayne Basilio de Sousa, Misael Bruno de Araújo
Federal Rural Semi-Arid University, Department of Agronomic and Forestry Sciences, Jitirana Research Group, Mossoró-RN, 59625-900, Brazil
Center of Exact and Natural Sciences, Federal Rural Semi-Arid University, Mossoró-RN, 59625-900, Brazil
Plant Science, Brazilian Service to Support at Micro and Small Enterprises of Rio Grande do Norte (SEBRAE-RN), Mossoró, RN, Brazil
Abstract
The objective of this work was to estimate the probabilities of the reference evapotranspiration (mm), as well as its accumulated values during 10 days (decendial), in Mossoró, RN, Brazil. It wass done through the daily records of evapotranspirations obtained at the Meteorological Station of the Federal Rural University of Semi-Arid (UFERSA), in Mossoró, RN, using the Penman-Monteith method. No previous transformation of the data was necessary since the construction of the tables was based on the approximation of the variable to the Normal distribution. The odds were estimated by the Normal distribution for the confidence levels of 1% to 95% in the data period from 1970 to 2007, taking into account the results of the chi-square and Kolmogorov-Smirnov tests at 10% probability. From the adequacy of the process of construction of the tables, it can be conclude and that studied values have important subsidies for planning of agricultural activities in the region, where the maximum benefits of their benefits are taken, avoiding their harmful effects.
Pages 204-211 | Full Text PDF| doi: 10.21475/ajcs.20.14.01.p2334