Genetic Characterization in 5 × 5 Diallel Crosses for Yield Traits in Bread Wheat

Abstract

The seed of five parental cultivars alongwith their 10 F 1 hybrids of wheat were sown in a randomized complete block design with four replications during 2010 at Sindh Agriculture University, Tandojam, Pakistan. Genetic analysis of yield traits from half diallel crosses was carried-out. Mean squares due to GCA and SCA were significant for days to 75% maturity, tillers plant -1 , spike length, spike density, grains spike -1 , grain yield plant -1 , seed index and harvest index. Significance of GCA and SCA variances suggested that both additive and non-additive genes were controlling these characters. The magnitude of SCA variances were higher than GCA indicating pre-dominance of non-additive gene effects for spike length, spike density, seeds spike -1 , grain yield plantand harvest index, while GCA variances were greater for days to 75% maturity, tillers per plant. Parental cultivar TD-1 expressed maximum GCA effects for tillers plant -1 , spike length, grain yield plant -1 , seed index and harvest index; while negative and desirable GCA for days to 75% maturity. The SCA estimates revealed that F 1 hybrid TD-1 × TJ-83 manifested maximum SCA effects for tillers plant -1 , spike length, grains spike -1 and negative yet desirable for days to 75% maturity. The cross TJ-83 × Sarsabz recorded with higher estimates for grains spike -1 , grain yield plant -1 , seed index and harvest index. Thus both the F 1 hybrids may be choice breeding material for hybrid crop development to improve the yield traits.

Heritability estimates and traits association in wheat advanced lines

“…Highly significant differences (P≤0.01) were observed for all the studied traits except harvest index which display significant differences (P≤0.05) among wheat genotypes (table 1). Similar findings were reported by many researchers and confirmed our results [15,[16][17][18][19][20][21][22][23].…”

“…These results are in conformation with the findings of Al-Tabbal and Al-Fraihat, [28]. For grains per spike, other researchers also reported high heritability estimates [16,17]. Grain yield ha -1 exhibited high heritability (69.01%) among fourteen advanced lines and four checks (table 3).…”

“…Plant Significant positive associations were obtained by Uddin et al [31] between grain yield and grains spike -1 , 1000-grain weight, flag leaf area and plant height. Further, many previous studies also found positive association between grain yield and grains spike -1 [32,17,12]. Biological yield is positively associated with grain yield and suggests that grain yield increase parallel with biological as it assists to accumulate additional photosynthates in developing grain.…”

Ear metabolism and genotype-by-environment interaction in field-grown durum wheat: identification of novel traits for crop improvement

“…Our study showed a medium heritability (48.7%) for NKS (Table 4.4). High heritability wasalso reported for NKS by Mohammadi et al (2011) and Gerema (2021) in durum wheat and by Baloch et al (2016) in bread wheat. For PL, TKW, SDSS and GI, heritability was medium Similarly, in previous studies, it has been found that heritability for SDSS varied from moderate to high (Clarke et al, 2010, Taneva et al, 2019, Taghouti et al, 2010.…”

“…SL could be considered a key trait, as larger spikes will likely produce more grains and increase yield. Baloch et al (2016) reported highly significant variation for this trait among bread wheat varieties and high heritability. The number of kernels per spike (NKS) contributes considerably to grain yield by increasing sink strength.…”