Forty isolates of endophytic bacteria isolated from banana tree roots were assessed as to their capacity to solubilize phosphate in a solid culture medium supplemented with different inorganic and one organic source of phosphorus. The amount of phosphorus (P) in each liquid medium was quantified, and an indirect assessment of acid phosphatase activity was performed. All assays had a fully randomized design, with three repetitions. Approximately 67.5% of the 40 isolates assessed in solid medium solubilized phosphorus from tricalcium phosphate and 7.5% of the isolates solubilized phosphorus from soy lecithin; no isolates exhibited P solubilization capacity in medium supplemented with iron phosphate . Acid phosphatase activity was detected in 65% of the isolates; Aneurinibacillus sp. and Lysinibacillus sp. isolates presented with the best solubilization indexes. All of the assessed isolates exhibited a capacity to reduce the potential of hydrogen in liquid medium supplemented with tricalcium phosphate. Isolate EB. 78 (Bacillus sp.) exhibited P solubilization capacity in solid media when Ca 3 (PO 4 ) 2 and soy lecithin were used as P sources; this isolate significantly reduced the pH of the liquid medium and exhibited acid phosphatase activity. The results of the present study highlight isolates that exhibit variations in their capacity to solubilize P. These isolates should be used in future tests to assess their field performance.

O presente trabalho visa discutir como o emprego da biotecnologia moderna,no que concerne o desenvolvimento de variedades geneticamente modificadas, tornou-seestratégia importante para o fortalecimento do agronegócio brasileiro e mundial. Nessesentido, aborda-se o histórico dos avanços do agronegócio mundial e brasileiro, coma implantação e comercialização dos produtos vegetais derivados da biotecnologia.O Brasil, um país rico em biodiversidade, considerado também celeiro mundial dealimentos tem se destacado no cenário internacional pelas pesquisas e desenvolvimentode produtos no campo da engenharia genética e genômica. Além disso, esse trabalhodemostra como o emprego da biotecnologia tem sido importante para o desenvolvimentode sistemas agrícolas mais produtivos e sustentáveis, beneficiando pequenos e grandesprodutores, aumentando assim a competitividade brasileira no mercado internacional.Por fim, as perspectivas do mercado biotecnológico para o agronegócio brasileirosão discutidas e analisadas buscando soluções para se desenvolver um país com altaprodução agrícola agregando as recentes ferramentas biotecnológicas.

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Drought is one of the main abiotic factors limiting agricultural productivity, capable of having a major impact on the yield of most crops. The knowledge of the physiological and biochemical mechanisms that differentiate resistance and susceptibility to water deficit among soybean strains can be used in the generation of more tolerant cultivars. In this sense, the objective of this study was to characterize physiologically, two soybean cultivars with different patterns of tolerance to drought in the field, by determining photosynthetic rates, lipid peroxidation levels and antioxidant enzyme activity under three levels of water potential. Upon reaching the V4 development stage, the irrigation of the plants was suspended and three data collection were performed: full irrigation (control); moderate water deficit (Ψ = -1.5 ± 0.2 MPa) and severe deficit (Ψ = -3.0 MPa ± 0.2 MPa). Variations in perspiration rate, stomatal conductance, as well as decrease in photosynthetic rate were significant between the two cultivars, where the water potentials in cultivar BR 16 anticipated on average two days achieving the same water potentials in Embrapa 48 cultivar, thus presenting better efficiency in water use. In addition, the increased activity of enzymes and lipid peroxidation were more significant in the cultivar BR 16, demonstrating that this cultivar is less tolerant to drought than Embrapa 48 cultivar, corroborating to agronomic data previously found in the field.

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The low number of ornamental pepper cultivars available in the market, combined with a high demand for this ornamental product, has boosted breeding programs for this crop. The objective was to morphologically characterize, estimating the genetic parameters of the main variables of ornamental importance in an F2 population of pepper (C. annuum). The experiments were conducted in a greenhouse at the experimental area of the State University of Montes Claros, Janaúba campus, MG, Brazil. The accessions Uni01 and Uni07 were used as parents to obtain F1 generations and, subsequently, a F2 population; 333 genotypes from the F2 generation were evaluated using 19 qualitative and five quantitative descriptors correlated to important characteristics for varietal description and ornamental use. Five fruits per plant were used to evaluate fruit characters: mean fruit weight, mean fruit length, mean fruit diameter, mean peduncle length, and mean pericarp thickness. The genetic parameters of quantitative descriptors were estimated using mean square expected values obtained through Anova. The genetic variability found can be explored for most evaluated characteristics. The quantitative descriptors related to fruit characteristics, based on heritability estimates, can be considered for selection.

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