Estratégia de melhoramento para tolerância ao estresse de calor em trigo

• Autor(a) principal: Ribeiro, Guilherme
• Data de Publicação: 2012
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/1347
• topic: Triticum aestivum L.; Temperatura; Ganho de seleção; Triticum aestivum L.; Temperature; Selection gain; CNPQ::CIENCIAS AGRARIAS::AGRONOMIA::FITOTECNIA::MELHORAMENTO VEGETAL

The extent of wheat production for the Central Brazil is a strategy to increase production of wheat. In this region the excess heat during the summer is a major factor in reducing yield potential. In the present study established the objective of identifying promising segregating populations for the development of lines with heat tolerance in wheat, selecting genotypes tolerant to heat stress and to estimate the genetic correlation coefficient between characters studied with grain yield. Two experiments were conducted in the summer of 2010 and 2011 in Coimbra / MG at the Experimental Station of Quartéis, belonging to the Universidade Federal de Viçosa (UFV) in the summer of 2010 were evaluated 36 segregating populations with varying number of families per population, determining the yield grain, plant height and cycle. In the summer of 2011 were evaluated 217 families selected in the previous year, for traits such as plant height, cycle, yield, the temperature depression of the flag leaf and ear. The occurrence of genetic variability for heat tolerance among populations of wheat and between selected families. The most promising segregating populations were IAC364/BRS207, IAC24/Aliança IAC24/Pioneiro and demonstrating the possibility of selecting families tolerant to heat stress with high yield potential. Selection of plants tolerant to heat can be successfully accomplished by selection based on the average grain yield and also by indirect selection by depression of the temperature of the flag leaf and ear.