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Porto Velho, Brazil

Silva S.M.M.,Federal University of Acre | Martins K.,Federal University of Sao Carlos | Mesquita A.G.G.,Federal University of Acre | Wadt L.H.O.,BR 364
Ciencia Florestal

The loss of diversity in tropical regions has been focus on several governmental and non-governmental discussions, focusing mainly on the fragmentation and destruction of natural ecosystems. However, decisions about the conservation of genetic resources must be guided by population genetic parameters, especially for species with economic interests that are subject to greater human interference. This study aimed to define and evaluate genetic parameters for the conservation of populations of Hymenaea courbaril in southwestern Amazon. This species is one of the most valuable and intensively exploited wood species in the Brazilian Amazon. We studied three forest areas prepared for logging in the background of sustainable management. It was calculated with eight microsatellite loci, genetic diversity, intra-population conservation estimators and genetic divergence among populations. Genetic diversity and fixation index were higher in the low density populations (< 0.08 ind.ha-1). The most density population (0.25 ind.ha-1) showed the lowest genetic diversity and no inbreeding. The Minimum Viable Area for species conservation was consistent with the reality of the studied areas, with a proviso for one of the populations where there is a need for a much larger area than the other to conserve populations. The genetic divergence was high (G'ST = 0.344) and the populations were considered Independent Management Units. Source

Morello C.L.,C.P. 179 | Pedrosa M.B.,Fundacao Bahia | Suassuna N.D.,Fundacao Bahia | Chitarra L.G.,Av. das Jacarandas | And 7 more authors.
Crop Breeding and Applied Biotechnology

Cotton cultivar BRS 335 is a midseason high-yield cultivar and has adaptation to the Northeast Brazilian savanna, yield stability, desirable resistance to main cotton diseases and good fiber quality. The cultivar BRS 335 meets growers' demands for competitive lint yield as well as fulfilling industrial textile requirements. Source

Partelli F.L.,Federal University of Espirito Santo | Espindula M.C.,BR 364 | Marre W.B.,Av. Vitoria | Vieira H.D.,State University of Norte Fluminense
Revista Brasileira de Ciencia do Solo

The period between anthesis and fruit ripening varies according to the Conilon coffee (Coffea canephora) genotype. Therefore, the time of the nutritional requirements for fruit formation may differ, depending on the formation phase and the genotype, and may directly affect split application of fertilizer. The aim of this study was to quantify the accumulation of dry matter and N, P, K, Ca, Mg and S at several stages in the fruit of the Conilon coffee genotype with different ripening cycles, which may suggest the need for split application of fertilizer in coffee. The experiment was carried out in the municipality of Nova Venecia, Espírito Santo, Brazil, throughout the reproductive cycle. The treatments were composed of four coffee genotypes with different ripening cycles. A completely randomised experimental design was used. with five replicates. Plagiotropic branches were harvested from flowering to fruit ripening at 28-day intervals to determine the dry matter of the fruits and the concentration and accumulation of the nutrients they contained. The behavior of dry matter and macronutrient accumulation during the study period was similar and increasing, but it differed among genotypes sampled in the same season. Early genotypes exhibited a higher speed of dry matter and nutrient accumulation. Split application of fertilizer should differ among coffee genotypes with different ripening cycles (early, intermediate, late and very late). Source

The objective of that work was to evaluate the influence of different soil mulching and doses of organic compost in the culture of the rocket. The experimental design was used in randomized blocks, in splitplot arrangement with four replications. The plot corresponded to the soil mulching (no-tillage with living mulch of Arachis pintoi, living mulch of native weed, straw mulch of native weed and conventional tillage without mulching). The plots represent the doses of organic compost (10, 20 and 30 t ha-1 in the dry compost). The variables analyzed were yield, commercial fresh matter, and dry matter of the aerial part. The dose of 30 t ha-1 provided the largest yield values and commercial fresh mass for the conventional system and straw mulch. The dose 20.49 t ha-1 increased yield and commercial fresh mass for A. pintoi mulch. The dose 20.85 t ha-1 showed greater increase in yield and commercial fresh mass for the live native weed. The tillage and straw mulch presented higher yield values for all the studied doses. The dose of 23.1 t ha-1 it promoted the largest dry mass of the aerial part. The tillage and no-tillage with straw mulch it contributed with the largest dry matter of the aerial part. Source

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