Open Access Original Research Article

Effect of Priming on Physiological Quality of Handroanthus serratifolius (Vahl.) Seeds

Girlânio H. Silva, Anderson C. José, Fabrício P. Teixeira, Luciana M. Gonzaga, Raul R. Molina, Jordânia X. Medeiros, Maurício H. Okada, Larissa Chamma

Journal of Experimental Agriculture International, Page 1-8
DOI: 10.9734/jeai/2019/v31i330071

This work aimed to evaluate the effect of different priming treatments in the longevity of H. serratifolius seeds. Seeds were osmo-conditioned in PEG -1.0 MPa at 10, 15 and 20°C or hydro-primed at 5, 10 and 15°C. Final germination, speed and uniformity of germination were assessed. Priming did not affect the final percentage nor uniformity of germination; however, the germination speed was increased after hydropriming at 15°C and osmo-conditioning at 15°C compared to the control. Primed and not primed seeds were placed into an incubator (25°C, dark, 100% RH) until they reached 15% moisture content. Then, seeds were incubated in a container at 40°C for 0 to 144 hours, so, samples were taken in each period for determination of viability. The results suggest that priming increases longevity of H. serratifolius seeds.

Open Access Original Research Article

Nitrogen Nutrition in Dry Tropical Forest at Different Times of Regeneration

Ágatha Maria de Oliveira Silva, Fernando José Freire, Mozart Duarte Barbosa, Rinaldo Luiz Caraciolo Ferreira, Maria Betânia Galvão Dos Santos Freire, Francisco Tarcísio Alves Júnior, Clarissa Soares Freire, Ane Cristine Fortes da Silva

Journal of Experimental Agriculture International, Page 1-7
DOI: 10.9734/jeai/2019/v31i330072

The management of forest species requires the quantification of various nutrients flows in the ecosystem. Specifically for N this aspect is even more important because many species in dry forests, as Brazilian Caatinga, are legumes and in symbiotic association with diazotrophic bacteria, fix N2 from the atmosphere. This study aimed to evaluate the N nutrition of forest species in Caatinga fragments with different regeneration times in the semi-arid region of Brazil. The study areas had different historical uses: the first one (53 ha) had no exploitation in the last 44 years; the second (32 ha) was in regeneration for 25 years; and the third (25 ha) had been in regeneration for five years. Four common tree species were evaluated in the three evaluated areas. Leaves were collected from each species to determine N contents. The legume species in the preserved area presented higher N content, decreasing with the regeneration time. The results showed a greater ecological balance in the most preserved sites, favoring the biological N fixation. N acquisition by legumes was not influenced by the disturbance of the site, suggesting the recommendation of these species as restorers of degraded areas.

Open Access Original Research Article

Variability in Morpho-biochemical Traits Associated with Pod Borer (Helicoverpa armigera) Resistance in Pigeonpea Pods

J. J. Cheboi, P. K. Kimurto, M. G. Kinyua

Journal of Experimental Agriculture International, Page 1-7
DOI: 10.9734/jeai/2019/v31i330073

Pigeonpea contributes to food and nutrition security among poor households in urban and rural areas. Globally it is characterized by stagnant and unstable yield due to its susceptibility to various stresses including the pod borer (Helicoverpa armigera) which causes substantial damage to the crop and may result in absolute economic yield loss. The existing cultivated pigeonpea are susceptible to pod borer with only a few genotypes reported to be tolerant based on pod and seed damage. Limited information is available on morphological and biochemical traits associated with pod borer resistance among the existing genotypes. This study was therefore carried out to identify diversified sources of resistance against pod borer damage. The study was set up to assess traits that may contribute to pod borer resistance among 12 selected elite pigeonpea genotypes in three replicates and means were separated based on LSD test using Genstat software. The field study was carried out in Kerio Valley during the long rains of April-September of 2017. The genotypes varied significantly for all the parameters measured at P≤0.05 with a mean of 608.33 g/100 g (crude protein), 175.61 mg/100 g (total phenol), 19.85 mg/100 g (total flavonoid), 0.448 mm (trichome length), 210.6 / 4 mm2(trichome density) and 0.353 mm(depth of locules). Significant negative correlation was also observed between total phenol, total flavonoid, depth of locules, trichome length and trichome density with pod damage. However, a positive correlation was recorded between crude proteins with pod damage.  These results reveal that, host plant resistance is an association of several morphological and biochemical traits. Therefore, these genotypes with elevated levels can be selected and utilized in breeding towards improving resistance to pod borer in pigeonpea.

Open Access Original Research Article

Selection in Base Population of Ornamental Peppers (Capsicum annuum L.)

José Ayron Moraes de Lima, Elizanilda Ramalho do Rêgo, Mirelly Miguel Porcino, Glauber Henrique Nunes da Silva, Michelle Gonçalves de Carvalho, Ângela Maria dos Santos Pessoa, Mailson Monteiro do Rêgo

Journal of Experimental Agriculture International, Page 1-7
DOI: 10.9734/jeai/2019/v31i330074

Aims: The aim of this study was to characterize and select plants with ornamental potential and resistant to pathogens in generation F2.

Study Design: For genetic divergence analysis, Tocher's grouping method was used, based on the standardized Euclidean distance. Analyses were carried out for the quantitative and qualitative data separately and also for the data together. In addition, the relative importance of the characteristics evaluated for genetic divergence was calculated using SINGH's Methodology (1981). All analyses were performed using the computational Genes program.

Place and Duration of Study: The experiment was conducted in a greenhouse of the Plant Biotechnology Laboratory of the Center of Agrarian Sciences (CCA) of the Federal University of Paraíba (UFPB). The treatments consisted of 354 progenies, an F2 generation of ornamental peppers (Capsicum annuum L), belonging to the Germplasm Bank of UFPB, derived from the controlled self-fertilization of F1 and obtained from the crossing between the parents UFPB390 X UFPB137. Plants grown in vessels of 900 mL filled with commercial substrate. There was variability among genotypes for the evaluated characters.

Methodology: Genotypes were characterized according to the descriptors for Capsicum suggested by IPGRI. 20 quantitative characters and 4 qualitative in ornamental peppers were evaluated. Leaves identified from an optical microscope using the illustrated descriptor of imperfect fungus.

Results: The variability between genotypes was higher for qualitative characters related to disease resistance. It is possible to select individual plants for opening lines in Generation F3. 7 plants; 7; 15; 50; 69; 120; 155; 157; 196; 314; 326; 331; 347 should be selected for not presenting symptoms of fungi diseases.

Conclusion: Greater diversity among genotypes was detected when the incidence of diseases in the plants was evaluated. The plants 7; 15; 50; 69; 120; 155; 157; 196; 314; 326; 331; 347 should be selected because they do not present symptoms of fungal diseases.

Open Access Original Research Article

Inter-relationships of Resistance to Penetration, Moisture and Soil Organic Matter with Irrigated Bean Yield in Mato Grosso do Sul, Brazil

Job Teixeira de Oliveira, Cassiano Garcia Roque, Rubens Alves de Oliveira, Rafael Montanari, Claudinei Martins Guimarães, Edcássio Dias Araújo

Journal of Experimental Agriculture International, Page 1-12
DOI: 10.9734/jeai/2019/v31i330075

The common bean (Phaseolus vulgaris L) can be cultivated practically throughout the year in different regions of Brazil, provided there are no water and temperature limitations. This study was carried out in a Quartzarenic Neosol, in the municipality of Cassilândia, state of Mato Grosso do Sul (MS), Brazil, in the 2016/2017 agricultural year. This study aimed to establish the linear and spatial interrelations of the penetration resistance (PR), gravimetric moisture (GM), and organic matter content (OM) with bean grain yield (GY) in the 0.00-0.10 and 0.10-0.20 m soil layers, collected in a mesh of 117 georeferenced points [81 points of the base mesh (6 m spacing among points)] and 36 mesh points with higher density (2 m spacing among points). Data analysis was carried out by statistical and geostatistical techniques that enabled to note that the organic matter content correlates linearly and negatively with penetration resistance, indicating that soil management practices aiming to increase its profile improve its physical conditions and therefore the bean grain development and yield. The gravimetric moisture and soil organic matter content correlate spatially, directly, and linearly with bean grain yield, proving to be the best properties among those surveyed to estimate and increase its agricultural productivity.