Open Access Original Research Article

Nematodes Associated to Tropical Forages in Pasture Areas

Bruna Nogueira Marques, Leimi Kobayasti, Giovani de Oliveira Arieira, Dayana Aparecida de Faria, Anne Caroline Dallabrida Avelino, Joadil Gonçalves de Abreu, Luciana Alves Martins, Gabriela Cristina Silva Moreira, Lucas Dias de Oliveira, Bruno Giuseppe Terzi

Journal of Experimental Agriculture International, Page 1-10
DOI: 10.9734/jeai/2019/v36i430239

The quantification of soil nematodes is of great importance for the management and evaluation of the efficiency of control methods, considering the damages caused in crops of economic interest. The present work aimed to quantify and identify plant parasitic nematodes in pasture areas in the municipality of Santo Antônio do Leverger, Mato Grosso state, Brazil. For that purpose, 25 soil and root samples were collected in four plots, consisting of the following forage grasses: Brachiaria humidicola cv. Common (Plot 1), Panicum maximum cv. Tanzania (Plot 2), Brachiaria brizantha cv. Marandu (Plot 3) and Panicum maximum cv. Massai (Plot 4). The nematode extraction from the soil and root samples was performed, followed by the quantification and identification of nematodes genera. The nematodes classified as free-living were observed in all plots, with population densities varying from 230 to 1180 specimens. The genus Pratylenchus presented the lowest population level, with 40 specimens, in the area where the Brachiaria humidicola cv. Common is cultivated. The following phytoparasitic nematodes genera were observed: Pratylenchus and Paratrichodorus associated to the Humidicola grass, and Heterodera and Criconemoides associated to the Tanzania grass.

Open Access Original Research Article

Fluorescence and Growth of Eggplant under Irrigation Levels and Silicon Doses

Reynaldo Teodoro de Fatima, Jackson Silva Nobrega, Daniel de Almeida Carreiro, Amaralina Celoto Guerrero, Adriana Silva Lima, Francisco Romário Andrade Figueiredo, Jean Telvio Andrade Ferreira, Marcos Eric Barbosa Brito

Journal of Experimental Agriculture International, Page 1-10
DOI: 10.9734/jeai/2019/v36i430240

Aims: The study was conducted to evaluate the fluorescence and growth of eggplant under influence of water deficit and silicon doses.

Study Design: The design was a randomized complete block design, in a 5 x 2 factorial arrangement, with four replications and one plant per plot, totaling 40 experimental units.

Length and Place of Study: The research was implemented between September and November 2016, in a greenhouse of the Center of Science and Technology Agrifood, at the Federal University of Campina Grande (UFCG / CCTA), Campus of Pombal-PB, Brazil.

Methods: Doses of 0, 75, 150, 225 and 300 mg L-1 of silicon and the irrigation slides of 50 and 100% of real evapotranspiration - ETr were used, which were obtained by weighing the pots daily in order to keep the weight close to the field capacity.

Results: The use of 50% level of the ETr provides reductions of 5.58; 7.92 and 6.84% of fluorescence in the initial, maximum and quantum yield of the photosystem. The fresh and dry mass of the stem presented the maximum productivity (140.8 and 48.1 g) in the plants irrigated with 100% Etr and treated with doses of 106 and 110 mg L-1 of Si.

Conclusion: The fluorescence and biomass of the eggplant plants is reduced with the decrease in irrigation level; while the application of silicon does not result in increment in the fluorescence and dry mass of the leaf. The 100% irrigation level of the ETr associated with the application of 108 mg L-1 of silicon resulted in the best results in stem mass accumulation.

Open Access Original Research Article

Vegetative Development and Productivity of the Watermelon under Different Irrigation Depths in the Northwest Region of Espírito Santo

Robson Prucoli Posse, Elio José dos Santos, Francielly Valani, Vinicius de Souza Oliveira, Sheila Cristina Prucoli Posse, Raphael Magalhães Gomes Moreira, Geilson Silva Costa

Journal of Experimental Agriculture International, Page 1-11
DOI: 10.9734/jeai/2019/v36i430241

Brazil is one of the main producers of watermelon crops (Citrullus lanatus), which present great water requirement and offer in their irrigated cultivation, when well managed, the possibility of productive gains and fruit quality. The objective of this study was to evaluate the productivity and the vegetative development of the plant and the watermelon fruits of the ‘Top Gun’ cultivar submitted to different irrigation depths in the Northwestern region of Espírito Santo. The experiment was carried out in the horticulture sector of the Federal Institute of Espírito Santo-Campus Itapina, from September 30, 2017 to December 15, 2017. A completely randomized design was used consisting of six treatments corresponding to 50%, 75%, 100%, 125%, 150% and 175% of the reference evapotranspiration (ETo) calculated daily, with four repetitions of each treatment. The length of the branches of all the selected plants and the longitudinal and transverse lengths of their fruits were evaluated weekly. In the last analysis, the fruit weight was also collected and the productivity was estimated. Development and differentiated production responses were verified with the different depths applied. Water replacements corresponding to the 125% ETo leaf gave the best vegetative and productive development of the watermelon ‘Top Gun’ cultivar, cultivated in the northwestern region of Espírito Santo.

Open Access Original Research Article

Evaluation of Physiological Quality of Seeds of Improved Snap Bean Lines under Different Storage

Camila Queiroz da Silva Sanfim de Santan, Luana Barros Freitas, Tâmara Rebecca Albuquerque de Oliveira, Jocarla Ambrosim Crevelari, Derivaldo Pureza da Cruz, Lilia Marques Gravina, Richardson Sales Rocha, Mário Euclides Pechara da Costa Jaeggi, Israel Martins Pereira, Márcia Teresinha Ramos Oliveira, Pedro Amorim Berbet, Geraldo de Amaral Gravina

Journal of Experimental Agriculture International, Page 1-10
DOI: 10.9734/jeai/2019/v36i430242

Seed quality is a key factor to succeed in a yield generation and storage is an important activity to control the physiological seed quality, as it preserves seed viability while maintaining its robustness at a reasonable level between planting and harvest. On this basis, the goal of this study was to evaluate the physiological quality of snap bean seeds stored in different types of packages and storage conditions. Eight genotypes comprising six lines and two controls were analyzed. It was applied a completely randomized block design with four replicates in a factorial scheme (8×2×2×7).Seed storage was performed in permeable and impermeable packages under controlled and uncontrolled conditions. The physiological seed quality was evaluated by means of germination and vigor tests. The different types of package and storage conditions influenced the physiological seed quality. Under controlled storage conditions, the permeable and impermeable packages were more efficient in controlling the physiological quality of snap bean seeds.

Open Access Original Research Article

Evaluation of the Insecticidal Potential of Six Plants Leaves Powders against Acanthoscelides obtectus Say on Stored Phaseolus vulgaris L.

A. I. Nta, A. A. J. Mofunanya, V. B. Ogar, P. A. Azuike

Journal of Experimental Agriculture International, Page 1-12
DOI: 10.9734/jeai/2019/v36i430243

Most plant powders possess insecticidal properties and can be used to control insect pests on stored products. This study was conducted to evaluate insecticidal properties of Solanum melongena, Parkia biglobosa. Ipomoea batatas, Colocasia esculenta, Tridax procumbens and Terminalia catappa   against Acanthoscelides obtectus Say, an insect pest of stored Phaseolus vulgaris L. The leaves powder of these plants were assessed for aduticidal and reproduction inhibition potential as well as effect on seed weight in a completely randomized design at three treatment concentrations of 0.5%, 1.0%, 1.5% and 0 as the control. All the test plants investigated exhibited insecticidal activity against A. obtectus. Results showed a trend of variation in adult A. obtectus mortality according to post-treatment days and plants powder concentrations. Results analysis revealed that at 14 days after treatment, T. catappa at 1.5% had the highest significant (P=0.05) mortality of 40.21±0.71i. This was followed by S. melongena which had a similar effect of 39.41± 0.52i at the same concentration (1.5%). The least significant mortality was observed in the control. At 0.5% T.  procumbens, 0.5% Parkia biglobosa, 1.0% I. batatas and 1.0% C. esculenta, leaves powder had comparable effects. It was observed that the control had the highest number of progeny emergence of 181.33 ± 0.88g after six weeks while T. catappa significantly (P=0.05) inhibited progeny at 1.5% followed by 1.5% S. melongena and 1.5% C. esculenta.  Seeds of P. vulgaris treated with 1.5% T. catappa also had the least significant weight loss of 0.93 ± 0.17 g compared to the control which had the highest significant weight loss of 55.68 ± 0.79 g. Though all the plants studied caused significant increase in adult A. obtectus mortality, reduction in progeny emergence and P. vulgaris seed weight loss than the control. Terminalia catappa however, exhibited the best insecticidal potential. Terminalia catappa and Solanum melongena were very effective in inhibiting the reproduction and progeny emergence of A. obtectus, but increased adult mortality resulting in weight loss suggesting their potential in controlling A. obtectus on stored P. vulgaris.