Australian Journal of Crop Science   AJCS

October 2020 | EARLY VIEW | 14(10):2020 | 10.21475/ajcs.20.14.10


Can different soil fertilization regimes modify soil fauna to interfere in maize grain yield?

Ana Luiza Privado Martins*, Glécio Machado Siqueira, Emanoel Gomes de Moura, Raimunda Alves Silva, Francisca Ferreira Farias, Alana das Chagas Ferreira Aguiar

Federal Institute of Maranhão, Povoado Poraquê, Zona Rural s/n, 65400-000, Codó – MA, Brazil
Geoscience Department – Federal University of Maranhão, Av. dos Portugueses 1966, Bacanga, 65080-805, São Luís – MA, Brazil
Graduate Program in Agroecology, State University of Maranhão, 65054-970, São Luís – MA, Brazil
Federal University of Maranhão, Av. dos Portugueses 1966, Bacanga, 65080-805, São Luís – MA, Brazil
Biology Department – Federal University of Maranhão, Av. dos Portugueses 1966, Bacanga, 65080-805, São Luís – MA, Brazil


Abstract
Soil fauna activities transform the soil, but soil organisms are also influenced by changes in the land. We hypothesize that different soil fertilization regimes modify soil fauna and in this way affect maize grain yield. The aim of this study was to evaluate the effects of different soil fertilization regimes on the structure of the soil fauna and the association between these organisms and the maize grain yield. The experiment was conducted in Maranhão State (Brazil), in an alley crop system which was divided into 32 plots of 4×10 m, with four replicates and the following treatments: Gliricidia sepium – gliricidia (G), potassium (K), humic acid (HA), humic acid + potassium (HA + K), potassium + gliricidia (K + G), humic acid + potassium + gliricidia (HA + K + G), humic acid + gliricidia (HA + G) and uncovered soil (US). Soil fauna dominance, abundance, richness, Shannon–Wiener diversity index, and Pielou evenness index and maize grain yield were determined. Fertilization with humic acid and potassium caused the dominance of isopods. The dominance of ants was also related to soil potassium (K treatment). The only taxon associated with yield was Araneae. Although fauna abundance did not show differences between treatments, it was related to yield. This study does not confirm the hypothesis that different soil fertilization regimes affect soil fauna and consequently influence maize grain yield. Nevertheless, we confirm that maize grain yield may be improved by the presence of specific groups and by the increased abundance of soil fauna.

Pages 1541-1548 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p1485
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Influence of nitrogen rates on the persistence of ryegrass (Lolium multiflorum L.) forage production

Diógenes Cecchin Silveira, Juliana Medianeira Machado, Luiz Pedro Bonetti, Ivan Ricardo Carvalho, Vinícius Jardel Szareski, Maurício Horbach Barbosa, Tiago Corazza da Rosa, Afonso Henrique Schaeffer, Eder Alexandre Minski da Motta, Natâ Balssan Moura

University of Passo Fundo, Passo Fundo, RS, Brazil
University of Cruz Alta, Cruz Alta, RS, Brazil
Federal University of Pelotas, Pelotas, RS, Brazil
Federal University of Porto Alegre, Porto Alegre, RS, Brazil.
Northwestern Regional University of the State of Rio Grande do Sul, Ijuí, RS, Brazil


Abstract
This work aimed at evaluating the influence of nitrogen rates on the persistence of ryegrass forage production during four agricultural years. The experiment was performed in the experimental area of the University of Cruz Alta, Brazil. The experimental design was complete randomized blocks, with four agricultural years (2013, 2014, 2015 and 2016) × four harvesting times (first, second, third and fourth) × seven nitrogen doses (0, 50, 100, 150, 200, 250 and 300 kg ha-1), arranged in four replicates. The application of nitrogen on natural re-sowing ryegrass promotes the increase in dry biomass production across agricultural years. The use of nitrogen as topdressing showed little effect on the persistence of ryegrass plants in the four years of study. The efficiency of nitrogen utilization was inversely proportional to the increment of the nitrogen doses used. It is fundamental to understand the behavior of nitrogen fertilization in pastures with natural re-sowing and its effects on the persistence of the plants throughout agricultural years, as well as their participation in the sustainability of agricultural activity.

Pages 1549-1554 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p1633
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Cropping system to produce lettuce in autumn season at different elevations

Luiz Fernando Favarato, Maurício José Fornazier, Frederico Jacob Eutrópio, Rogério Carvalho Guarçoni, Lidiane Mendes

Research Center, Development and Innovation Serrano, Instituto Capixaba de Pesquisa, Assistência Técnica e Extensão Rural, Br 262, Km 94, 29375-000 Venda Nova do Imigrante, Espírito Santo, Brazil
Multivix College Vila Velha, Rua Sete de Setembro - Centro de Vila Velha, Vila Velha - ES, 29100-301, Espírito Santo, Brazil
Research Center, Development and Innovation Serrano, Instituto Capixaba de Pesquisa, Assistência Técnica e Extensão Rural, Br 262, Km 94, 29375-000 Venda Nova do Imigrante, Espírito Santo, Brazil
Graduate student in Food Science and Technology, Instituto Federal do Espírito Santo, Campus Venda Nova do Imigrante, 29375-000 Venda Nova do Imigrante, Espírito Santo, Brazil


Abstract
Lettuce is an annual herbaceous plant, native to the mild climate regions of the northern Mediterranean. Lettuce varieties can likely be developed well in mild temperatures, but the cold and frosty winds of the autumn/winter season may damage the leaves. Their cultivation under low tunnels is an alternative to reduce this problem. This study was carried out with the aim of evaluating the influence of different cropping systems on the productive performance of lettuce in the autumn/winter cropping season. The experiments were installed following a split plot scheme with three cropping systems: (i) Open field with black polyethylene mulching (BPM); (ii) low tunnel (LT); (iii) Open field cropping (OFC) system without BPM. Three lettuce varieties of different groups were used in the subplots, with a total of nine treatments. The experimental design was of randomized blocks with four replications, at two altitudes (700 and 950 m). The number of leaves per plant, stem length, head diameter, fresh and dry matter mass per plant, leaf area index, and specific leaf area were evaluated. LT should be used for lettuce cultivation at an altitude of 950 m, as it provided higher productive performance in the autumn season. The use of the low tunnel provided for the production of lettuce plants with thinner leaves and better visual appearance, at an altitude of 700 m.

Pages 1555-1562 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p1769
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Qualitative characterization of secondary metabolites of Paspalum virgatum weed under different water conditions

Paulo Cesar Laurindo Silva*, Oscar Mitsuo Yamashita, Ivone Vieira da Silva, Adriano Maltezo da Rocha, Bruna Zonta de Brito, Vanessa de Andrade Royo, Keyla Laisa Araújo Saldanha, Marco Antonio Camillo de Carvalho, Aureane Cristina Teixeira Ferreira Cândido, Ricardo Adriano Felito, Maria Carolina da Silva Andrea, Ana Aparecida Bandini Rossi

Federal Institute of Mato Grosso, Campus of Confresa, MT, Brazil
Postgraduate Program in Amazonian Biodiversity and Agroecosystems, Mato Grosso State University, Campus of Alta Floresta, MT, Brazil
Postgraduate Program in Biotechnology, Montes Claros State University, Montes Claros, MG, Brazil


Abstract
The presence of weeds amid pastures has caused significant damage to cattle farmers due to the difficulty in controlling these species. Paspalum virgatum stands out as an aggressive weed in Amazonian agroecosystems. Proper management of weed species is threatened by their aggressiveness, adaptation to low fertility soils and morphological, physiological and biochemical similarities with the grasses used as fodder. It is also possible that part of these characteristics of aggressiveness occur due to the ability of weeds to produce allelochemicals, resulting in damage to surrounding plants. The objective of this study was to qualitatively verify the presence of secondary metabolites in P. virgatum species under different water availability. The analyzed species were initially grown separately under three conditions of water availability: water deficit, field capacity and flooded environment. The water deficit treatment was conducted to verify weed ability to develop under conditions of extreme water shortage. This is a characteristic related to its rusticity, as found in grasses in the Amazon region. Excess water treatments were also conducted, since this is a common condition found in areas with partial flooding of a few months during the rainy season in the Amazon. After 120 days, weeds were collected and separated into roots, stems and leaves. The material was subsequently dried, ground and subjected to procedures to determine secondary metabolites. Phenolic compounds, flavonoids and alkaloids were identified in all conditions of plant development. The flavonoid detection test presented an intense yellow color. This is a strong indication of the presence of this class in stems and leaves of plants under flood and in leaves of plants under field capacity soil conditions. An intense presence of phenolic compounds was verified in stems and leaves, regardless of treatment. General alkaloids were found in great intensity in all samples. Saponins were found in leaves of P. virgatum under water stress (flooding and water deficit). All the metabolites were found in the plants, diverging between treatments and parts of the plant. It was concluded that the species presented higher steroid content in the roots when growing in places with excess of water. In conditions of full water supply, the presence of steroid was less intense in the roots, leaves and stems, result also found in roots and leaves of plants under water deficit. Alkaloids were less intensely present in the roots, regardless of the water treatment in which the plant was submitted. Results demonstrated that there are secondary metabolites responsible for some physiological ability of the weed to withstand excess or water deficit, indicating the need for further studies.

Pages 1563-1567 | Full Text PDF| Supplementary PDF| doi: 10.21475/ajcs.20.14.10.p2200
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Distribution of corn plants in a pneumatic system with different vacuum pressure adjustments and seed sieves

José Carlos Casaroto Madaloz, Alcir José Modolo*, Juan Paulo Xavier de Freitas, José Ricardo da Rocha Campos, Murilo Mesquita Baesso, Lucas Dotto, Emerson Trogello

Federal Technological University of Paraná, Pato Branco, Paraná, Brazil
University of São Paulo, Pirassununga, São Paulo, Brazil
Goiano Federal Institute, Morrinhos, Goiás, Brazil


Abstract
The use of seeders with pneumatic distribution systems is increasingly demanding for plantation of corn crop. Knowledge about the operation and adjustments of the components of agricultural machines is fundamental to increase the good distribution of plants and to ensure higher productivity. The main goal of this research was to evaluate the influence of the size of the corn seed sieve under different vacuum pressure regulations on a pneumatic distribution system, to understand the longitudinal uniformity of the plants, as well as the final and individual productivity per plant. The vSet® (Precision Planting®) pneumatic distribution system equipped with 4 corn seed sieves (C1, C4, R1, and R4) subjected to 4 different vacuum pressure adjustments (7, 12, 17 and 22 in H2O-1) was applied as treatments on corn hybrid 30F53VYH. The design used was that of randomized blocks, with subdivided plots and 4 replications. The main plot presented the vacuum pressures and the subplots presented the sieves, each composed of two sowing lines of 20 m in length. The results showed that low vacuum pressure resulted in increased unevenness between corn spacings and consequently lower yield. Smaller sieves showed less gaps and higher percentages of normal spacing. The larger sieves showed higher standard deviation and more gaps. Regular and uneven gaps provided a higher number of grains per row, higher number of grains per corn spike and a higher grain yield per corn spike.

Pages 1568-1574 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p2316
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Identifying morphological diversity and superior germplasm of Citrus reticulata Blanco (Mandarin) in Sikkim and Darjeeling Himalayas, India: an application of DIVA-GIS and cluster analysis

Subhankar Gurung, Arun Chettri*, Meera Tamang and Mamta Chettri

Taxonomy and Biodiversity Laboratory, Department of Botany, Sikkim University, Gangtok, Sikkim, 737102, India

Abstract
Citrus reticulata is an important cash crop for the farmers in the Sikkim and Darjeeling Himalayas, India. The lack of knowledge of its diversity has only resulted in the lack of uniformity in the fruit quality. It has become imperative to identify superior varieties that meet the demands of the market to improve the citrus industry. Hence, a total of 105 accessions of mandarin were collected randomly from different locations to assess the morphological diversity using cluster analysis and DIVA-GIS. The orchards were randomly visited in each district of the state of Sikkim and two hilly districts of the state of West Bengal (WB). A sample tree was selected from each orchard and the quantitative and qualitative characters of its leaves, flowers, and fruits were measured. A significant variation was observed in the quantitative characters with a positive correlation between fruit weight and length, fruit diameter and weight, total soluble solids (TSS) /acidity and fruit diameter. The first 6 components of Principal component analysis (PCA) exhibited 69.34% of the total variation. DIVA-GIS showed the highest diversity index for fruit weight, fruit diameter and TSS/acidity in East district, Sikkim. The highest coefficient variation for fruit diameter was observed in the East district and Darjeeling district, WB and TSS/acidity and fruit weight in East district. The dendrogram generated divided the accessions into two major clusters. The grid maps generated identified diverse accessions in the East district and Darjeeling district, which can be a source of superior germplasm.

Pages 1575-1582 | Full Text PDF| Supplementary PDF| doi: 10.21475/ajcs.20.14.10.p2351
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Sexual propagation of common Bahia cocoa seedlings (Theobroma cacao L.) influenced by irrigation depths and the planting seasons

Robson Prucoli Posse, Vinicius de Souza Oliveira, Francielly Valani, Stefany Sampaio Silveira, Sophia Machado Ferreira da Silva, Carlos Alberto Spaggiari Souza, Sheila Cristina Prucoli Posse, Geilson Silva Costa, Edilson Romais Schmildt

Federal Institute of Espírito Santo – Campus Itapina, Colatina, Espírito Santo, Brazil
Federal University of Espírito Santo – Center Noth of Espírito Santo, São Mateus, Espírito Santo, Brazil
Cacao Research Station “Filogônio Peixoto” - CEPLAC, Linhares, Espírito Santo, Brazil
Capixaba Institute for Research, Technical Assistance and Rural Extension, Vitória, ES, Brazil


Abstract
Cocoa (Theobroma cacao L.) is one of the most economically important species due to its use in the production of chocolate, honey, pulp, animal feed, fertilizers, jellies, butter and cocoa powder. The production of seedlings such as through sexual propagation is the essential stage for the establishment of new cocoa crops, in which the seedlings are produced by seeds. This is the most commonly used method in cocoa. Several factors interfere with the final quality of the seedlings, such as the planting season and the irrigation management. Thus, the objective of this study was to evaluate the effects of different irrigation depths and planting seasons on the quality and growth of Bahia genotype cocoa seedlings produced through sexual propagation. The study took place at the Federal Institute of Espírito Santo, Campus Itapina, in Colatina, located in the Northwest region of the State of Espírito Santo, Brazil. The experimental design was completely randomized in a split-plot scheme. The plots consisted of six different irrigation depths: 4, 6, 8, 10, 12 and 14 mm d-1 and the subplots, of three different planting seasons: autumn, winter and spring. At 50 days after sowing, the seedlings were evaluated for the following morphological characteristics: plant height, stem diameter, leaf area, length of the root system, dry mass of the aerial part, dry mass of the root system, total dry mass and Dickson quality index. The production of Common Bahia genotype cacao seedlings is more effective in the irrigation depth of 9.44 mm d-1, demonstrating better development and higher plant quality.

Pages 1583-1588 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p2364
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Genetics of angular leaf spot (ALS) resistance in South African market class dry bean (Phaseolus vulgaris) cultivars

Josephine T. Pasipanodya*, Rob Melis, Deidre Fourie

Department of Plant Breeding, University of KwaZulu-Natal, Pietermaritzburg, South Africa
Department of Crop Science, University of Namibia, Oshakati, Namibia
African Centre for Crop Improvement, University of KwaZulu-Natal, Pietermaritzburg, South Africa
ARC-LNR, Grain crops Institute, Potchefstroom, South Africa


Abstract
Angular leaf spot (ALS) caused by Pseudocercospora griseola (Sacc.) is one of the serious fungal diseases affecting dry bean in Africa, including South Africa. Host plant resistance is the best management strategy, of which its effectiveness requires knowledge of the genetics underlying the resistance in guiding breeding efforts. In this study, the inheritance of ALS resistance was studied through the generation mean analysis biometrical procedure. Six generations consisting of the two parents Ukulinga and Gadra, and its cross derived filial progenies (F1), second-generation (F2), and backcrosses of F1 to Ukulinga (BCP1) and Gadra (BCP2) were planted in a net-house and later inoculated using a mixture of P. griseola isolates. Leaf lesions (% disease severity) were rated using a CIAT 1-9 scale and analysed using SAS macros in Proc GLM of SAS version 9.3. Results of ANOVA for a full model displayed significant additive effects (P<0.05) and highly significant (P<0.001) additive x dominance effects. Segregation analysis indicated a 9:7 ratio, implying the involvement of complementary gene effects. The number of genes was estimated to be 1.79; however, due to epistasis two or more genes possibly govern the resistance in this cross. Broad and narrow sense heritabilities were 0.40 and 0.33, respectively. Therefore, the estimated narrow-sense heritability, additive gene effects, and epistatic interaction imply that it is prudent to delay selections until later stages, in which homozygosity could be achieved and additive effects fixed.

Pages 1589-1594 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p2370
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Growth and production of colored fiber cotton (Gossypium hirsutum L) subjected to salt stress and potassium fertilization

Jéssica Dayane Capitulino, Carlos Alberto Vieira de Azevedo, Geovani Soares de Lima, André Alisson Rodrigues da Silva, Luana Lucas de Sá Almeida Veloso, Hans Raj Gheyi, Raul Araújo da Nóbrega, Lauriane Almeida dos Anjos Soares, Vera Lúcia Antunes de Lima

Federal University of Campina Grande, Academic Unit of Agricultural Engineering, Campina Grande, 58.109-970, Paraíba, Brazil
Federal University of Campina Grande, Academic Unit of Agricultural Science, Pombal, 58.840-000, Paraíba, Brazil
Federal University of Recôncavo of Bahia, Nucleus of Soil and Water Engineering, Cruz das Almas, 44.380-000, Bahia, Brazil


Abstract
Temporal and spatial variation of rainfall in semiarid regions may lead to an increase in the concentrations of salts present in irrigation water, and it is necessary to adopt techniques to reduce the negative effects of salts on plants. Thus, the present study aimed to evaluate the growth and production of colored cotton cv. BRS Topázio as a function of irrigation using water with different levels of salinity and potassium doses. The experiment was carried out in pots adapted as lysimeters under greenhouse conditions, using a non-saline Neossolo Regolítico (Entisol) of sandy texture. The experimental design was randomized blocks, with 4 replicates, with treatments distributed in a 4 x 4 factorial scheme, corresponding to four levels of saline irrigation water electrical conductivity (1.5; 3.0; 4.5 and 6.0 dS m-1) and four potassium doses (50; 75; 100 and 125% of the recommendation), with a dose of 100% corresponding to 150 mg K2O per kg-1 of soil. Irrigation using water of electrical conductivity (saline) above 1.5 dS m-1 negatively affected the growth and production of cotton cv. BRS Topázio, and cotton seed weight was the most sensitive variable. Potassium doses above 50% of the recommendation in interaction with salinity reduced the height and leaf area of cotton cv. BRS Topázio.

Pages 1595-1600 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p2374
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Salinity management strategies and potassium fertilization in watermelon (Citrullus lanatus) cultivation

Saulo Soares da Silva, Geovani Soares de Lima, Vera Lúcia Antunes de Lima, Hans Raj Gheyi, Lauriane Almeida dos Anjos Soares, Rômulo Carantino Lucena Moreira, Pedro Dantas Fernandes, Elysson Marcks Gonçalves Andrade, Francisco Wesley Alves Pinheiro

Federal University of Campina Grande, Academic Unit of Agricultural Engineering, Campina Grande, 58.109-970, Paraíba, Brazil
Federal University of Campina Grande, Academic Unit of Agrarian Sciences, Pombal, 58.840-000, Paraíba, Brazil
Federal University of Recôncavo of Bahia, Nucleus of Soil and Water Engineering, Cruz das Almas, 44.380-000, Bahia, Brazil


Abstract
This study aimed to evaluate the gas exchanges and growth of ‘Sugar Baby’ watermelon under different strategies of irrigation with saline water and potassium fertilization, in an experiment conducted in a protected environment. The experiment was conducted in randomized blocks, in 8 x 3 factorial arrangement, corresponding to eight water salinity management strategies applied at the phenological stages of the crop (NS = no stress along the cycle; VE = salt stress during vegetative stage; VE/FL = salt stress during vegetative and flowering stages; FL = salt stress during flowering stage; FL/FR = salt stress during flowering and fruiting stages; FR = salt stress during fruiting stage; FR/MAT = salt stress during fruiting and maturation stages; MAT = salt stress during fruit maturation stage) and three potassium doses – KD (corresponding to 50, 100 and 150% of the recommendation), with three replicates. Two levels of water salinity were used, high and low values of electrical conductivity (ECw = 0.8 and 4.0 dS m-1). Watermelon growth and gas exchanges, especially transpiration, stomatal conductance, CO2 assimilation rate, instantaneous carboxylation efficiency, and absolute and relative growth rates of stem diameter were compromised by water salinity at the stages of flowering, fruiting and maturation. The potassium dose with 50% of K2O recommendation can be used in the cultivation of watermelon, without negatively affecting gas exchange and growth.

Pages 1601-1607 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p2388
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Tetradenia riparia (Lamiaceae) essential oil: an alternative to Rhipicephalus sanguineus

Giuliana Zardeto-Sabec, Renan Almeida de Jesus, Herika Line Marko de Oliveira, Caio Franco de Araújo Almeida Campo, Ezilda jacomassi, José Eduardo Gonçalves, Zilda Cristiani Gazim*

Programa de Pós-Graduação em Biotecnologia Aplicada à Agricultura. Universidade Paranaense - UNIPAR, Praça Mascarenhas de Moraes, 4282, CEP 87502-210, Umuarama-PR, Brasil
Mestrado em Tecnologia Limpas e 3Instituto Cesumar de Ciência, Tecnologia e Inovação – ICETI. Centro Universitário Cesumar-UNICesumar, Av. Guedner, 1610. Jardim Aclimação, Maringá, Paraná, 87050-900, Brasil
Mestrado Profissional em Plantas Medicinais e Fitoterápicos na Atenção Básica, Universidade Paranaense (UNIPAR), Praça Mascarenhas de Moraes, 4282, Umuarama, PR, 87502-210, Brasil


Abstract
In Brazil, Rhipicephalus sanguineus resistance to some pyrethroids have been detected, motivating research on new phyto-insecticides such as essential oil from Tetradenia riparia leaves (EOL) and flower buds (EOFB). The essential oils were obtained by hydrodistillation (3h) and identified by GC/MS. In addition, a multivariate exploratory analysis was done to determine the analysis of the major compounds (PCA). The bioassays on R. sanguineus larvae were done by immersion test at different EO concentrations which ranged from 50,000 to 0.47 mg/mL (v/v). The action mechanism of EOs were determined by bioautographic method evaluating the inhibitory potential on the acetylcholinesterase enzyme. The EO yield in leaves was 0.29±0.22 (%) and in flower buds 0.38±0.17 (%). The class projections showed oxygenated sesquiterpenes (43.62%) and diterpenes (15.60%) in EOFB, and hydrocarbon sesquiterpenes (26.44%) and oxygenated monoterpenes (16.44%) in EOL. Four components presented a greater distancing of mass flow: fenchone (11.57 and 6.01 %), α-cadinol (12.21 and 13.69 %), 14-hidroxy-9-epi-caryophyllene (8.56 and 15.38 %), and caryophyllene oxide (1.32 and 4.50 %) in EOL and EOFB, respectively. The lethal concentrations (LCs) to kill R. sanguineus larvae were (LC50: 2.18±0.24 and LC99.9: 9.98±0.10 mg/mL) for EOL, and (LC50: 5.36±2.50 and LC99.9: 20.12±0.54 mg/mL) for EOFB. The action mechanism of EOs by bioautographic methods indicated an inhibition of 0.70 mg/mL (EOL) and 1.40 mg/mL (EOFB) on the acetylcholinesterase enzyme (AChE). Therefore, this species can be considered promising to be part of the chemical larvicides to control this ectoparasite.

Pages 1608-1615 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p2389
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Vegetative growth of 28 genotypes of Coffea canephora at 850 meters of altitude

Madlles Queiroz Martins, Fábio Luiz Partelli*, Adelmo Golynski, Nivaldo de Sousa Pimentel, Adésio Ferreira, Weverton Pereira Rorigues, José Cochicho Ramalho

Programa de Pós-Graduação em Genética e Melhoramento, Centro de Ciências Agrárias e Engenharias, Universidade Federal do Espírito Santo, Alegre - ES, Brasil
Departamento de Agronomia, Centro de Ciências Agrárias e Engenharias, Universidade Federal do Espírito Santo, Alegre - ES, Brasil
Departmento de Ciências Agrárias e Biológicas, Centro Universitário Norte do Espírito Santo, Universidade Federal Espírito Santo, São Mateus - ES, Brasil
Instituto Federal Goiano, Campus de Morrinhos, Rodovia BR-153, Km 633, Zona Rural. Caixa Postal 92, CEP 75650-000 - Morrinhos – Goiás, Brasil
Centro de Ciências Agrárias, Naturais e Letras, Universidade Estadual da Região Tocantina do Maranhão, Estreito, MA, 65975-000, Brasil
Plant-Environment Interactions & Biodiversity Lab (PlantStress&Biodiversity), Linking Landscape, Environment, Agriculture and Food Unit (LEAF), Dept. Recursos Naturais, Ambiente e Território (DRAT), Instituto Superior de Agronomia (ISA), Universidade de Lisboa (ULisboa), Quinta do Marquês, Av. República, 2784-505 Oeiras, Portugal
Unidade de Geobiociências, Geoengenharias e Geotecnologias (GeoBioTec), Faculdade de Ciências Tecnologia (FCT), Universidade NOVA de Lisboa (UNL), Quinta da Torre, 2829-516 Caparica, Portugal


Abstract
Coffea canephora plants grown at low or elevated temperatures undergo changes in photosynthetic processes, which have a direct impact on vegetative growth. This species shows plants with distinct stress tolerance mechanisms and a great genetic diversity; however, there are no studies concerning the study of altitude on plant growth for these genotypes. The objective of this study was to evaluate the growth rates of orthotropic and plagiotropic branches from 28 Coffea canephora genotypes, ca. 3 years of age, cultivated at 850 m of altitude. The experimental design was a randomized complete block design with four repetitions. Each repetition was compounded by five plants. The period of the experimental evaluation was from 01/23/2013 to 07/07/2013. We selected and identified the orthotropic and plagiotropic branches, which were evaluated bimonthly according to their length (mm), assessing the growth rates. The results were associated with climatic factors that occurred during the experimental period. The genetic material of Coffea canephora evaluated in the study shows genetic diversity to the characteristics growth rate of orthotropic and plagiotropic branches, thus, it is possible to select genotypes with potential for cultivation at 850 m of altitude. In general, genotypes of Coffea canephora exhibited variations in growth rates, mainly in response to changes in temperature, with a sharp and constant drop in growth rates between the period from 05/05/2013 to 05/ 23/2013, when the recorded temperatures were always below 13 °C. Genotypes A1, NV2 and NV1 can be pointed as the ones which showed the best vegetative growth results at 850 meters of altitude.

Pages 1616-1622 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p2392
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Drying kinetics of Hyola 430 hybrid canola (Brassica napus L.) seeds

Lílian Moreira Costa, Osvaldo Resende, Daniel Emanoel Cabral de Oliveira, José Mauro Guimarães Carvalho, Sarah Gabrielle Sousa Bueno, Wellytton Darci Quequeto*

Instituto Federal de Educação, Ciência e Tecnologia Goiano, Campus Rio Verde, Goiás, Brazil
Instituto Federal de Educação, Ciência e Tecnologia Goiano, Campus Iporá, Goiás, Brazil


Abstract
This work aimed to study the drying kinetics of canola seeds, fit mathematical models and obtain the effective diffusion coefficient. Canola seeds with initial moisture content of 0.3653 (decimal, d.b.) were subjected to drying in a forced ventilation oven at temperatures of 40, 60, 80 and 100 °C and relative humidity of 37.15, 16.93, 8.35, 4.41 and 2.47%, respectively. The samples were dried on trays without perforations, containing approximately 77 g, in three replicates. A final moisture content of 0.080 ± 0.004 (decimal, d.b.) was established to determine the drying curves and fit the mathematical models. The mathematical models were selected considering the mean estimated error, chi-square, coefficient of determination, mean relative error, and Akaike (AIC) and Bayesian (BIC) information criteria. Drying time decreased with increasing temperature. Based on the best values of the statistical parameters and together with the Akaike and Bayesian information criteria, the Page model was selected to represent the drying kinetics of canola seeds. The effective diffusion coefficients showed magnitudes between 0.153x10-11 and 1.221x10-11 (m2 s-1), and their values increased with temperature increase, being described by the Arrhenius equation, with activation energy of 33.94 kJ mol-1, an important piece of information to consider when designing drying equipment.

Pages 1623-1629 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p2400
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Nutrient uptake analysis of black cohosh (Actaea racemosa L.) grown under shade in greenhouse

Julia Robinson, Guochen Yang, Sanjun Gu, Zhongge (Cindy) Lu, and Bryce Holmes

College of Agriculture and Environmental Sciences, North Carolina A&T State University, Greensboro, North Carolina, USA

Abstract
This research was determining optimal fertilizing strategies for Black cohosh, as an herbal alternative for menopause, to increase crop productivity. Nutrient uptake was analyzed on one-year old plants grown under 80% shade in a greenhouse and exposed to two nutrient application treatments: single and continuous exposures of fertilizer at 0%, 2%, 4%, 6%, 8% and 10% concentrations during a one-year study. Two respective experimental designs were used for growth data and nutrient uptake analysis. Growth data was using a Completely Randomized Split Plot Design, with two treatment groups, single exposure and continuous exposures of fertilizer, and six subplots for each concentration. Nutrient uptake analysis was using a Completely Randomized Design and conducted only on single exposure fertilizer treatment for total amount of calcium, iron, potassium, magnesium, manganese and zinc. Single exposure (5 replications) of fertilizer had one application of fertilizer solution per concentration, to soil, one week before planting, while continuous exposure (7 replications) of fertilizer had an initial application of fertilizer solution one week before planting and subsequent application of fertilizer solution per concentration, once a week for entire growing season. Continuous exposure led to a significant decrease in growth and rhizome weights, and a significant increase in stem number per plant as fertilizer concentration increased. No growth change was observed with a single exposure of fertilizer, except for a decrease in stem length. Black cohosh mainly utilizes calcium, potassium, magnesium and zinc as it fully matured, and manganese since initial growing stage. Calcium and magnesium accumulated primarily in leaves, while potassium accumulated in stem and iron in rhizome.

Pages 1630-1636 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p2436
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Combining ability analysis of yield and resistance to late blight disease caused by Phytophthora infestans in Uganda

Prossy Namugga*, Julia Sibiya, Rob Melis, Alex Barekye

African Centre for Crop Improvement, University of KwaZulu-Natal, School of Agricultural, Earth and Environmental Sciences, Private Bag X01, Scottsville 3209, Pietermaritzburg, South Africa
National Agricultural Research Organisation (NARO), P.O.Box 421 Kabale, Uganda


Abstract
Breeding for resistance to late blight disease caused by Phytophthora infestans (Mont.) de Bary in potato is the most economically, effective and ecologically sustainable method to control the disease and boost productivity. The study estimated combining ability effects of yield, yield related traits, late blight resistance and gene action controlling resistance to Phytophthora infestans. Eighteen F1 families generated from two sets of 12 parents, using a North Carolina Design II, were evaluated for relative area under disease progress curve (rAUDPC), yield and yield related traits in two late blight hotspot locations of Kachwekano and Kalengyere research stations. Trials were established using an alpha lattice design (6 x 5) with two replications. Both additive and non-additive genetic effects were important in controlling yield and late blight resistance. However, additive gene action was dominant. The general combining ability (GCA) to specific combining ability ratio (SCA); (GCA/SCA) for total tuber weight and late blight resistance was 0.53 and 0.62 respectively. Broad-sense heritability estimates were 0.78 for total tuber weight and 0.68 for relative area under disease progress curve (rAUDPC). This study showed some evidence of maternal effects for rAUDPC (1.45) and average tuber weight (ATW) (1.56), although these were not significant at P<0.05. Parents Kinigi, 392657.8, 396034.103, 396038.107, 395011.2, NKRK19.17, NKRN59.58 and 395017.14 had good GCA effects for both late blight resistance and yield related traits. Crosses of 392657.8 x 395017.14 and 396038.107 x NKRN59.58 had the highest SCA effects for yield related traits, while families Kinigi x NKRK19.17and 392657.8 x NKRN59.41 had the lowest SCA effects for rAUDPC. The relatively high heritability estimates and predominant additive genetic effects imply that genetic advances in resistance to Phytophthora infestans and tuber yield among these genotypes can be realized by selecting superior clones.

Pages 1637-1644 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p2437
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Effects of photoperiod, potassium, and growth regulators on micropropagation of Ocimum basilicum L. ‘Genovese’

Vanessa F. F. Welz, Jéssica R. Trettel, Andressa B. Nascimento, Leticia N. Barbosa, Hélida M. Magalhães

Programs in Biotechnology Applied to Agriculture, Paranaense University, Mascarenhas de Moraes Square, 4282, 87502-210 Umuarama, Paraná, Brazil
Paranaense University, Umuarama, Mascarenhas de Moraes Square, 4282, 87502-210 Umuarama, Paraná, Brazil


Abstract
Medicinal plants are important in the pharmaceutical, cosmetic, and food industry owing to the diversity of their chemical composition. Basil (Ocimum basilicum L.) is a medicinal plant that is frequently used to produce cosmetics and food. However, the effects of factors such as photoperiod, growth regulators, and nutrients on growth during micropropagation are not comprehensively understood. The objective of this study was to assess the effect of different photoperiods and growth regulators on in-vitro growth and biochemical activity of the O. Basilicum 'Genovese' cultivated using a potassium-supplemented culture medium. The experiments were carried out in a completely causalized design and were conducted using a Murashige and Skoog culture medium plus sucrose and agar. In the first experiment, seeds were inoculated at three different photoperiods in the presence or absence of growth regulators. In the second experiment, growth media containing five different concentrations of potassium iodide (KI) (0, 25, 50, 75, and 100 μM) were used. Basil seedlings grown at photoperiods of 16h and 24h produced more leaves and larger length and shoot mass, and addition of growth regulators showed no effect. However, the root systems produced the highest average values at a photoperiod of 16 h and when growth regulators were supplemented (0.23 g ±0.08). Antioxidant activity and the concentration of ascorbate peroxidase were higher under the 16 h light treatment and with addition of growth regulators. Addition of potassium to the growth medium had no beneficial effects on seedlings. Antioxidant activity was not affected by potassium concentrations, but it remained high (above 13.5%) when compared with the previous treatment. Catalase activity was the highest in seedlings grown at the highest concentrations of KI. The catalase enzyme is considered a stress indicator, so in higher concentrations of KI there is evidence that the basil plants may have had oxidative damage.

Pages 1645-1653 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p2447
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Rhizobacterium Serratia sp. and phosphorus fertilization rates affect aerobic rice development

Adriano Stephan Nascente*, Marta Cristina Corsi de Filippi, Thatyane Pereira de Sousa, Amanda Abdallah Chaibub, Alan Carlos Alves de Souza, and Anna Cristina Lanna

Brazilian Agricultural Research Corporation (EMBRAPA), Rice and Beans Research Center, P.O. Box 179, Highway 462, km 12, Santo Antônio de Goiás, State of Goiás, 75.375-000, Brazil
Escola de Agronomia, Universidade Federal de Goiás, Goiânia - GO, Brazil
Departamento de Fitopatologia, Universidade de Brasília, Brasília - DF, Brazil
Departamento de Fitopatologia, Universidade Federal de Lavras, Lavras - MG, Brazil


Abstract
Beneficial microorganisms participate in different processes that affect transformation of soil nutrients, including phosphorus (P), making them available for plants. However, there are few studies about the use of beneficial microorganism and P fertilization in the development of aerobic rice. The objective was to determine the effect of Serratia spp. isolate BRM 32114 and doses of P at sowing on the production of biomass, gas exchange, nutrient content in leaves and grain, grain yield and its components of aerobic rice. The field experiments were conducted over two growing seasons, 2015/16 and 2016/17, under a no-tillage system in the Brazilian Cerrado. The experimental design was a complete randomized block in a factorial 4x2x2 scheme, with four replications. The treatments consisted of four P2O5 doses (0, 40, 80 and 120 kg ha-1) with or without rhizobacterium (2) in two growing seasons (2). Phosphorus rates increased the number of panicles and grain yield of aerobic rice, and the grain yield was higher in Serratia inoculation compared to no inoculation. The Serratia spp. strain BRM 32114 inserted in the production system of aerobic rice, under no-tillage, promoted gas exchange activity; enriched the K+, Ca+2 and Mg+2 content in leaves; enhanced biomass accumulation (13%), and resulted in a higher number of panicles per plant (11%) and grain yield (19%) than untreated plants. Therefore, this beneficial microorganism is a promising technology for potential incorporation into cropping systems in Tropical regions of the world.

Pages 1654-1661 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p2522
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Spatial arrangement of maize plants aiming to maximize grain yield in the hybrid BRS-3046

Marcus Willame Lopes Carvalho, Edson Alves Bastos, Milton José Cardoso, Aderson Soares de Andrade Junior, Carlos Antônio Ferreira de Sousa

Center of Agrarian Sciences, Federal University of Piaui - UFPI, 99997-8911, Teresina, PI, Brazil
Embrapa Mid-North, 3198-0500, Teresina, PI, Brazil


Abstract
The objectives of this study were to: (i) evaluate the effect of different spatial arrangements on morpho-physiological characteristics and (ii) determine the optimal spatial arrangement to maximize grain yield of the maize hybrid BRS-3046 grown in the Mid-North region of Brazil. We tested two row spacings (0.5 and 1 m) and five plant densities (2, 4, 6, 8, 10 plants m-2), which corresponded to 10 different plant spatial arrangements. Different morphophysiological variables, gas exchange rates and grain yield were measured. The increased planting density led to a linear increase in LAI, regardless of row spacing, while the net CO2 assimilation rate increased until the density of 4 and 6 plants m-2, under a row spacing of 0.5 and 1.0 m, respectively. On the other hand, we found a linear reduction in the stomatal conductance with increasing planting density. The intercellular CO2 concentration and the transpiration rate were higher in the widest row spacing. The instantaneous efficiency of carboxylation, in turn, showed a slight increase up to the density of six plants m-2, then falling, regardless of row spacing. Increasing plant density resulted in a linear increase in plant height and ear insertion height, regardless of row spacing. However, it had an opposite effect on stem diameter. Grain yield, in turn, increased up to 7.3 plants m-2 at a row spacing of 0.5 m and 8 plants m-2 at a row spacing of 1.0 m. This spatial arrangement was considered as ideal for achieving maximum yield.

Pages 1662-1669 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p2525
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Sustainable alternatives for post-harvest strawberry conservation

Léo Omar Duarte Marques*, Jorge Atílio Benati, Josiane Duarte de Carvalho, Paulo Mello-Farias, Tâmara Foster Acosta, Flavio Gilberto Herter, Mateus da Silveira Pasa

Federal University of Pelotas, Capão of Leão Campus, Pelotas, RS, Brazil

Abstract
Strawberries show a short post-harvest conservation period. To improve it, the effect of different post-harvest storage temperatures, conservation methods and three different storage periods were tested on ‘San Andreas’ strawberry, right after harvest. The experiment consisted of a three factorial 2 x 5 x 3 (temperatures x methods x storage periods), arranged in a completely randomized design (CRD). Four replications were used for each treatment, each with five sampling units. The treatments tested were: storage temperatures - 1°C and 18°C (T1 and T2); conservation methods - sodium hypochlorite 0.5% (C1), potato starch film 6% + sodium hypochlorite 0.5% (C2), cassava starch film 6% + sodium hypochlorite 0.5% (C3), UV-C radiation (C4), and control (no treatment) (C5); Storage period - 3, 6, and 9 days (D1, D2, D3, respectively). The parameters assessed were flesh firmness, color (hue angle, chroma, and luminosity), soluble solids (SST) and mass loss. Fruit kept at a temperature of 1°C showed better traits than those stored at 18°C, regardless of the method and storage period. Among the conservation methods tested, only UV-C and sodium hypochlorite improved some attributes (firmness and SST) when associated with refrigeration at 1°C. The use of potato and cassava starch is not as expected since they do not improve conservation and the total soluble solids contents.

Pages 1670-1674 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p2550
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Intercropping of beet with salad rocket (Eruca sativa) using hairy woodrose (Merremia aegyptia) plus manure goat in loam argisol yellow red latosol

Lunara de Sousa Alves, Paulo César Ferreira Linhares*, Roberto Pequeno de Sousa, Janilson Pinheiro de Assis, Thiago Jardelino Dias, Joaquim Odilon Pereira, Eudes de Almeida Cardoso, Robson Pequeno de Sousa, Mateus de Freitas Almeida dos Santos, Walter Martins Rodrigues, Geovanna Alícia Dantas Gomes, Anderson Bruno Anacleto de Andrade, Maria Fernanda de Oliveira Soares

Federal University of Paraiba, Campus Areia, Areia-PB, 58397-000, Brazil
Federal Rural Semi-Arid University, Department of Agronomic and Forestry Sciences, Jitirana Research Group, Mossoró-RN, 59625-900, Brazil
Departamento de Engenharias e Ciências Ambientais, Universidade Federal Rural do Semi Árido, Mossoró, Brazil, Mossoró-RN, 59625-900, Brazil
Computing Department, State university of Paraíba, Campina Grande-PB, 58429-500, Brazil


Abstract
The crop intercropping is a viable option for family farmers who grow in small spaces and need to take advantage of all the available area. The objective of this study was to evaluate the agronomic viability of the intercropping of beet with salad rocket (arugula) under different amounts of Merremia aegyptia plus goat manure. The experiment was conducted at Rafael Fernandes Experimental Farm, in the Alagoinha district, rural area of Mossoró-RN, from August to December 2016. The experimental design was a randomized complete block with treatments arranged in a 2 x 4 factorial scheme, with three repetitions. The first factor was the single beet and second intercropped cultivation of beet and arugula. The second factor was the amount of Merremia aegyptia plus goat manure (0.0, 1.5, 3.0 and 4.5 kg m-2). For the sugar beet crop the following characteristics were evaluated: plant height, fresh leaf mass, commercial root yield and root dry mass. For arugula culture the following characteristics were evaluated: plant height, number of leaves per plant, yield, number of sauces and dry mass. The best agronomic performance of the beet and rocket intercropping was obtained in the amount of 4.5 kg m-2 of M. aegyptia beds and goat manure. The consortium presented an area ratio equivalent to over 1.0, with an average value of 1.81 in the amount of 4.5 kg m-2 of M. aegyptia flowerbed plus goat manure. The consortium contributed to better use of available resources without compromising the commercial quality of the vegetables.

Pages 1675-1681 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p2723
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The effects of a QTL for root development under hypoxia on yield of soybean exposed to 7-day waterlogging at seedling stage

Dang Thi Thu Hien, Nguyen Van Loc, Tomomi Abiko, Toshihiro Mochizuki

Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 744, Motooka, Nishi-ku, Fukuoka, 819-0395, Japan
Faculty of Agronomy, Vietnam National University of Agriculture, Trau Quy, Gia Lam, Hanoi, 131000, Vietnam
Faculty of Agriculture, Kyushu University, 111 Harumachi, Kasuya-cho, Kasuya-gun, Fukuoka, 811-2307, Japan


Abstracts
In humid parts of the world, waterlogging is a major environmental stress limiting the yield of soybean and its root development is an important indicator of tolerance. Recently, quantitative trait loci (QTLs) for this trait were detected on the chromosome 12 of soybean through the analyses of recombinant inbred lines (RILs) developed from a cross between a hypoxia-sensitive cultivar, Tachinagaha, and a tolerant landrace, Iyodaizu. In this study, in order to get a detailed understanding of these QTLs, NIL-9-4-5, a near-isogenic line (NIL), was selected from Tachinagaha/Iyodaizu BC6F2 population through marker assisted selection (MAS). NIL-9-4-5 was then tested for yield performance under waterlogging conditions exposed at the seedling stage. The test was conducted in a greenhouse in 2015 and 2018 at the Experimental Farm of Kyushu University, Fukuoka, Japan. Soybean plants were grown in pots containing loam soil. From six days after germination, seedlings were grown for 7 days under two treatments: drained (control) and waterlogging conditions. Pots were kept in containers where the water level was maintained at 2.0 cm depth from bottom in the control and at 2.0 cm above the soil surface in waterlogged condition. Experimental results consistently showed that seed yields of both Iyodaizu and NIL-9-4-5 were not reduced under waterlogging. Compared to Tachinagaha, NIL-9-4-5 showed higher root development and increased seed yield under waterlogging. These indicate that the tested QTLs are able to increase yield by stimulating root development under waterlogging.

Pages 1682-1687 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p2739
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Fallow periods on a secondary forest with Platonia insignis Mart. in western Brazilian Amazon

Larissa de Paula Viana da Silva, José Ribamar Gusmão Araujo, Ariadne Enes Rocha, Raudielle Ferreira dos Santos, Wyayran Fernando Sousa Santos, Mário Luiz Ribeiro Mesquita*, Francisca Helena Muniz

Universidade Estadual do Maranhão, Programa de Pós Graduação em Agroecologia, CEP 65055-310, São Luis, Maranhão Brasil
Universidade Estadual do Maranhão, Departamento de Fitotecnia e Fitossanidade CEP 65055-310, São Luis, Maranhão Brasil
Universidade Estadual do Norte Fluminense Darcy Ribeiro, CEP 28.013-602, Campos dos Goitatazes, Rio de Janeiro, Brasil
Universidade Estadual do Maranhão, Programa de Pós Graduação em Agricultura e Ambiente, CEP 65055-310, São Luis, Maranhão Brasil


Abstract
Changes in the structure of the vegetation reflect on the biodiversity and dynamics of the ecosystem. The objective of the study was to characterize and compare the structure of fragments of vegetation with the occurrence of Platonia insiginis, in different stages of regeneration, with 6, 10, 25 and 100 years of fallow period in western Brazilian Amazon. The study was conducted in a completely randomized design, with four treatments, consisting of 6, 10, 25 and 100 years of fallow period, and five replications, consisting of demarcated temporary plots for each fallow period, with dimensions of 2 m x 2 m for the regenerating stratum of vegetation and 10 m x 10 m for the adult stratum of vegetation. Phytosociological parameters evaluated were number of individuals and species, total density, total height, stem diameter and Shannon DiversityIndex (H’), Pielou Equability (J) and Jaccard Similarity Index (JSI). The data were subjected to the Analysis of Variance, followed by the Tukey Test (p <0.05) and Principal Component Analysis. There was low species diversity for the sampled areas, with (H’) rates ranging from 0.65 to 2.46 nats ind-1. The vegetation fragments with 100 years of fallow period showed a floristic similarity of 10% with the others, while those of 6 and 10 years of fallow period, reached similarity of 40%. For the regenerating strata only, the number of individuals and total density differed, with the lowest averages, respectively, of 5 and 1,400 individuals ha-1 at 100 years of fallow period. For the adult strata, there was a difference between all parameters corroborating the results obtained in the Principal Component Analysis, at 100 years of fallow period, a lower average was obtained for the number of individuals (7), and higher averages of plant height (22.1 m) and diameter at breast height (36.45 cm). As conclusion, the time required for the complete natural regeneration of secondary vegetation fragments in the Brazilian Amazon is over 100 years.

Pages 1688-1694 | Full Text PDF| Supplementary PDF| doi: 10.21475/ajcs.20.14.10.p2811
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Growth and quality of SJ-02 cocoa seedlings (Theobroma cacao L.) under different irrigation depths and cultivation containers

Vinicius de Souza Oliveira, Stefany Sampaio Silveira, Robson Prucoli Posse, Laís Gertrudes Fontana Silva, Valeria Pancieri Sallin, Gabriel Sossai Pancieri, Matheus Pancieri Sellin, Victor Luchi Guerra, Carlos Alverto Spaggiari Souza, Geilson Silva Costa, Moisés Zucoloto, Edilson Romais Schmildt

Federal University of Espírito Santo - Center for Agricultural Sciences and Engineering, Alegre, Espírito Santo, Brazil
Federal Institute of Espírito Santo – Campus Itapina, Colatina, Espírito Santo, Brazil
Federal University of Espírito Santo – Center Noth of Espírito Santo, São Mateus, Espírito Santo, Brazil
Cacao Research Station “Filogônio Peixoto” - CEPLAC, Linhares, Espírito Santo, Brazil


Abstract
The study aimed to evaluate the growth and quality of SJ-02 cocoa seedlings under different irrigation depths and cultivation container sizes. The experiment was arranged as a completely randomized design, in a factorial scheme (4x3), where the first factor consisted of the application of four different irrigation depths (6, 10, 12 and 14 mm d-1) and the second one was composed of three different cultivation containers (small, medium and large). Twelve treatments were evaluated with eight repetitions, totaling 96 plants in the experimental field. At 74 days after sowing, the leaf area, stem diameter, plant height, dry mass of the aerial part, dry mass of the root system, total dry mass and Dickson's quality index of all seedlings were analyzed. The 10.32 mm d-1 irrigation depth and the medium and large cultivation containers provided the highest quality in seedling production, being the most suitable ones. However, there was no interaction between the factors.

Pages 1695-1700 | Full Text PDF| doi: 10.21475/ajcs.20.14.10.p2848