Caráter stay-green e produtividade de grãos em trigo

Abstract

); GUILHERME RIBEIRO ( 3,6 ); CYRANO CARDOSO BUSATO ( 3 ) RESUMOO caráter stay-green é um dos fatores que poderá auxiliar o melhorista na obtenção de plantas mais produtivas, devido à permanência verde por um período mais prolongado favorecendo o enchimento de grãos. Desta forma, o objetivo do trabalho foi o de avaliar o desempenho de diferentes constituições genéticas de trigo com e sem a presença do caráter stay-green e verificar se a expressão de alelos que intensificam a coloração verde por um período mais prolongado, os quais auxiliam no incremento da produtividade de grãos. O trabalho foi desenvolvido em campo experimental com delineamento de blocos casualizados com três repetições, em dois anos de cultivo. A presença de constituições genéticas superiores facilita os benefícios expressos pelo caráter stay-green na produtividade de grãos. O caráter stay-green proporciona estabilidade na produtividade de grãos sob efeito de diferentes ambientes.Palavras-chave: Triticum aestivum L., permanência verde, melhoramento de plantas. ABSTRACT STAY-GREEN TRAIT AND WHEAT GRAIN YIELDThe stay-green trait is one of the factors that can aid the breeder in obtaining higher yielding plants due to a delay in leaf senescence, favouring grain filling. The objective of this study was to evaluate the performance of different wheat lines with and without the stay-green trait and investigate if longer green period; foster an increment of grain yield. The field experiment was conducted in randomized complete block design with three replications in two crop years. Genetically superior lines facilitate the benefits of the stay-green trait for grain yield. The stay-green trait promotes yield stability under different environments.

Recurrent selection as breeding strategy for heat tolerance in wheat

“…The estimate of h 2 for grain yield was > 56% in all cases, a rate considered relatively high (Silva et al 2008). For plant height, the lowest estimate was > 64%, and for flowering > 85% (Table 2).…”

Stay-green: a potentiality in plant breeding

“…Abiotic stress tolerance is a major feature of stay-green genotypes, giving stability to grain yield even in unfavorable environmental conditions (SILVA et al, 2008). Superiority of grain yield in staygreen lines when compared to synchronized sibling lines, was especially restrictive in environmental conditions such as low rainfall at the end of the cycle (LUCHE et al, 2013).…”

“…Stay-green is the term given to a variant in which senescence is delayed in comparison to a standard reference genotype (THOMAS; HOWARTH, 2000;JOSHI et al, 2007). The stay-green character is characterized by a longer green state of the plant in the late period of grain filling, establishing a senescence pattern in which leaves and stem are the last parts to loose photosynthetic ability, providing greater production of sugars from photosynthesis (SILVA et al, 2008). Based on the increase of grain filling ability and improvement of desirable traits, it is suggested that the character results in yield gains.…”

Prediction of parental combination for introduction of stay-green associated loci in wheat

“…In southern Brazil, a significant contribution of stay-green trait for grain yield and abiotic stresses tolerance has been observed (Luche et al 2013). The low complexity of stay-green i.e., its reduced number of genes can facilitate the breeder's work incorporate into elite genotypes, besides the great contribution involving high additive effects on inheritance (Joshi et al 2007), a condition that favors the selection pressure in early generations in achieving significant genetic gains (Silva et al 2008a).…”