Heterosis, Combining Ability and Their Inter-Relationship for Morphological and Quality Traits in Yellow Maize (Zea mays L.) Single-Crosses Across Environments

Abstract

The research aimed to study heterosis, combining ability and performance along with their interrelationship across three environments. Variance due to general (GCA) and specific combining abilities (SCA) and their interaction with environment was found to be significant for most of studied traits. For all the studied traits but ASI (Anthesis-silking interval), HI (Harvest index) and starch content, additive gene action was highly important than non-additive gene action for their expression as reflected by Baker's ratio which was near to unity. CML439, R13-1-1 and Tarun83-1-3-2 were the best general combiner for starch, protein and oil, respectively. R13-1-17, CML439 and Tarun83-1-3-2 were good general combiner for maturity characters and harvest index while TSK 196 and TSK 197 were good general combiner for cob length, cob girth, number of grains/row and grain yield. DMR9047×R13-1-17 and POP31Q×Tarun83-1-3-2 showed desirable heterosis and SCA effect for maturity characters. Regarding to SCA and heterosis, the prominent hybrids for grain yield were TSK197×R13-1-10, TSK194×POP31Q, DMR9047×POP31Q and R13-1-1×DMR9047. SCA established stronger relationship with per se performance of grain yield and quality traits than mid-parent (MPH) and best-parent heterosis (BPH), reflecting that an improvement in selection of SCA will results in an indirect improvement of MPH and BPH of hybrids.

Genetic Parameters in Mesocotyl Elongation and Principal Components for Corn in High Valleys, Mexico

“…These results were the same as [47] in terms of CW, CL, NGR, weight of 100 grains (WHG), grain yield per plant (GYP) and de-kernelling index (DKI %). Other authors, such as [48,49], have obtained similar results, including those for grain yield. While, at the other extreme, Ref.…”

“…Likewise, there was a higher effect of SCA on LM and COP2. Later studies, such as [48], indicate that this could be useful to identify parents and combinations for a better yield, which could later be useful in recurrent-reciprocal selection or hybridization programs [65]. However, the SCA for LM-LC and TBWS (Table 1 and Figure 3) of some contrasts of mesocotyls could be underestimated and negatively affected by the variation in the air and soil temperatures during seedling emergence, which ranged between 13 and 31 • C and between 19 and 25 • C (Figure 5A), since corn is a crop that is sensitive to variation in air temperatures [66], where high and low temperatures can reduce the growth rate and seedling development [67].…”

Combining ability effects and heterosis estimates in maize (Zea mays L.)

“…These hybrids may be commercialized as early maturing maize hybrids after confirmation of their suitability for commercial cultivation. Good level of negative heterosis for maturity traits in maize genotypes have also been reported by Rajitha et al (2014), Talukdar et al (2016, Bhusal and Lal, (2020). The top five hybrids that showed highly significant standard heterosis in desirable direction for grain yield per plant were L1xT1 (51.26 %), L2xT1 (32.88 %), L5xT1 (31.11 %), L6xT2 (30.44 %) and L8xT3 (29.68 %).…”

Combining Ability of Indonesian Tropical Maize in Two Different Seasons

“…The best heterosis (MPH and HPH) for EL is positive, while TP is negative. Heterosis of ear diameter (ED) character shows a relatively positive value and combinatiion of pairs G5 x G3, G6 x G4 and G6 x G5 which have a significantly different SCA effect, also had significant variation on MPH (Bhusal & Lal, 2020). The same results were found in the research of Kamara, El-Degwy, & Koyama (2014).…”