Inheritance Pattern of Earliness and Yield Related-Traits in Spring Barley (Hordeum vulgare L.)

Abstract

To understand the genetic patterns of the physio-morphological traits for barley grain yield, six-generations (P 1 , P 2 , F 1 , F 2 , BC 1 , and BC 2 ) were used to determine the type of gene action in the four barley crosses. Grain yield showed a strong positive association (r = 0.83 and 1) with Grain Filling Rate in Giza121/RIL1 and Giza126/RIL2 crosses, respectively. The relationship between yield and earliness was not consistent with crosses and positive (r) values were quite low. It should be possible to select early-maturing and high-yielding segregates with high 100-kernel weight. The results indicated that the dominance effect [dd] was more important and greater than the additive effect [aa] and [ad] for most traits. Positive heterosis over the mid-and better-parent was quite similar for the most traits, except for heading and maturity dates, that showed negative heterotic effects. The inbreeding depression was high significant and positive for Grain Filling Rate, chlorophyll contents, Flag Leaf area and 100-kernel weight. On the other hand, it was a negatively significant for the earliness trait (HD, MD, and GFP). The lack of uniformity for estimates of inbreeding depression can be explained by environmental variation and to its influence on the type of gene action. Narrow-sense heritability ranged from 13.3% for Grain Filling Period in Giza12/RIL1 to 66.6% for heading dates in Giza121/RIL2 crosses. Genetic advance estimates were low due to lack of additive variance. The crosses Giza121/RIL1 and Giza126/RIL2 would be of interest in a breeding program, for improving characteristics of earliness, yield, and its components.Keywords: Hordeum vulgare L., type of gene action, heterosis, heritability IntroductionBarley (Hordeum vulgare L.) is a crop with great adaptive potential in many regions of the world. In areas which have only a brief rainy season, growers can obtain a harvest mainly because this crop has advantages in aspects such as salt tolerance, frost tolerance in the early period of development, drought tolerance, etc. Breeding for quantitative traits in early generations is impeded by several factors such as polygenic nature and low heritability of a trait (grain yield, the number of spikes per plant, etc.), linkage, non-additive gene effects and environmental effects (Harlan, 1976).In order to overcome these difficulties, it is necessary to get as much information as possible about the genetic structure of breeding population undergoing selection (Sharma et al., 2003). This means identifying the gene effects that control the inheritance of a trait of interest and contributing to the exploitable genetic variance of the population.Grain yield increase would be effectively rested with the basis of the capabilities of yield components and other closely associated traits. In cereal crops, the upper three leaves on the stem, especially the uppermost leaf, i.e., flag leaf, are the primary source of carbohydrate production. The flag leaf could contribute a large proportion of the carbohydrates...

Genome‐wide transcriptomic and functional analyses provide new insights into the response of spring barley to drought stress

“…To realize these goals, the barley program has developed several breeding strategies, including the screening of exotic and local materials in field trials and utilizing elite materials as parents. Giza 134 is a promising spring cultivar on the recommended list of barley varieties for the newly reclaimed lands in Egypt (Elakhdar et al, 2023). In the current study, we used the high-throughput RNA-seq approach to investigate the potential regulatory factors/ genes that may control drought tolerance in barley and could be utilized for developing drought-resilient and high-yielding barley cultivars.…”