Magnitude of hybrid vigor retained in double haploid lines of some heterotic rice hybrids

Abstract

Sixty one double haploid (DH) lines were evaluated for yield components and yield and compared with the three corresponding hybrids from which they were derived through anther culture. Analysis of a 6×6 diallel experiment led to the selection of these hybrids based on their high heterosis and revealed the nature of gene action of the characters under evaluation. The DH lines along with the hybrids and parents were planted following a simple lattice design with two replications. The results show that in DH lines the values of the characters expressing predominantly additive genetic effects could reach the heterotic level of the hybrids. For characters including yield showing predominantly dominance effects, values in the DH lines were significantly lower than those of the corresponding hybrids. The promising DH lines, however, possess a higher yield potential than the better parents.

Haploids: Constraints and opportunities in plant breeding

“…Furthermore, Polok et al (1997) isolated heterotic DH lines with yield potential similar to control cultivars, indicating the suitability of DH technique for the exploitation and fixation of heterosis. This approach was also used to select for heterotic DH lines from mutant crosses in rice, which out-yielded the better parents but with comparable performance to the heterotic F 1 s (Ba Bong and Swaminathan, 1995;Maluszynski et al, 2001). It was, however, noted the importance of dominance and additive genetic effects controlling grain yield parameters in the investigated populations.…”

Doubled Haploids in Crop Improvement: Unraveling Strategies, Advancements and Prospects for Enhanced Genetics

“…By comparing the performance of DHs with their corresponding parental lines, breeders can evaluate the degree of heterosis and select the most promising hybrids for commercial production. Understanding and harnessing heterosis can lead to the development of high-performing hybrid varieties with superior traits [48].  Genetic Stability: Double haploids offer genetic stability since they are homozygous and exhibit fixed genetic traits.…”

Meta-Analysis of Influence of Diversity of Parental Forms on Heterosis and Specific Combining Ability of Their Hybrids

“…Heterosis is the increased exuberance, vigor, and fertility of hybrids compared to the initial parental forms, as a result of the crosses from which they were derived [4]. Underlying heterosis are phenomena of gene interaction that, for example, through the occurrence of heterozygous systems and, in particular, through dominant systems result in better adaptation of hybrids to the environment or outright greater productivity [5][6][7]. Heterosis plays a key role in plant breeding and is important in both agriculture and research.…”