Combining Ability and Heterosis in Diallel Analysis of Maize (Zea mays L.) Lines

Abstract

<jats:p>A sound breeding program for maize improvement is very important to meet the demands of the growing population. Therefore, combining ability and heterosis were studied in a 4 x 4 full diallel cross in maize for growth attributes, yield and its contributing traits. Randomized Complete Block Design (RCBD) with four replicates was used to study the general combining ability of parents, specific combining ability of F1s (including reciprocals) and heterosis of the F1s over commercial check variety on selected agronomic characters. Genotype was highly significant for all the traits studied. The combining abilities (GCA and SCA) and reciprocal mean squares were highly significant for most studied characters. The ratio of GCA/SCA was not less than unity for studied traits excepted for days to anthesis and ear height. The results indicated that the additive genetic effects were more important and played major role in studied traits. Thus, results revealed GCA effects for the parental lines (PL). Where ‘PL2’ was excellent combiner for number of tassels and cob circumference and ‘PL3’ was good combiner for days to silking and grain yield (t.h-1). While ‘PL4’ for short height. Majority of the F1s from the GCA effects showed high SCA effects. This F1 (PL2 x PL3) performed best amongst. However, several reciprocals were not desirable. Heterosis estimation was carried out using a commercial check, Oba super II. When commercial check was used, the percent heterosis especially on grain yield varied from -8.89 to 22.62%. Among the twelve F1s, nine of the crosses exhibited significant positive heterosis for grain yield (t.h-1). Those F1s that showed significant positive and/or negative desirable traits for SCA effects and significant positive heterosis could be used for varietal development in maize breeding. And conservation of those parents that exhibited high GCA effects be considered as well.</jats:p>

Combining Ability and Gene Action Using 10 X 10 Diallel Crosses of Ten Maize Inbred Lines (Zea mays L.)

“…The results showed that the general combining ability (GCA) and specific combining ability (SCA) variances were significant or highly significant for all the studied traits, indicating that both additive and non-additive gene action were important in the inheritance of these traits. The present results were inconsistence with those obtained by Rezaei and Roohi (2004) for EH, Srdić et al (2007) for GY, Aly and Mousa (2011) for DTS, PHT, EHT, EP % and GY, Bisen et al (2020) for DTS and PHT and Onejeme et al (2020) for DTS, PHT, EHT and GY traits. The ratio of GCA/SCA was more than unity for all the studied traits, revealing the importance of additive gene action in the genetic control of these traits.…”

“…The ratio of GCA/SCA was more than unity for all the studied traits, revealing the importance of additive gene action in the genetic control of these traits. Similar results were obtained by Dawood et al (1994) and Amer (2002) for DTS, PHT and EHT, Bello and Olaoye (2009) for DTS, PHT and GY, Aly and Mousa (2011) for DTS, PHT, ED and GY, Haydar (2020) for GY, El-Hosary (2020) for DTS and Onejeme et al (2020) for DTS, PHT traits. The mean squares due to GCA x Loc and SCA x Loc were highly significant for all the studied traits, meaning that both additive and non-additive gene effects were affected by environmental.…”

“…General, the superiority% crosses than the check hybrid should be considered in breeding programs for higher yielding and other agronomic traits. These results were confirmed with the results by Uddin et al (2006), Aly and Mousa (2011), Mohammed et al (2016) and Onejeme et al (2020).…”

“…Meanwhile, seven crosses positive and not significant superiority% over check hybrid; Sd.3118 x Gm.6052, Sd.3180 x Sk.1, Sd.3180 x Sd.15, Sd,3180 x Sd.21, Sk.1 x sd.21, Mall.5035 x Sd.21 and Gz.658 x Sd.21. Numerous researchers were obtained similar results such as Amiruzzaman et al (2010), Aly and Mousa (2011), Abebe et al (2020) and Onejeme et al (2020). General, the superiority% crosses than the check hybrid should be considered in breeding programs for higher yielding and other agronomic traits.…”

Identification of promising parental lines and hybrids in sweet corn (Zea mays L. saccharata)

“…Most of the authors reported combining ability and heterosis studies in normal corn (Amegbor et al, 2020;Bisen et al, 2020;Elmyhun et al, 2020;Gramaje et al, 2020;Kamara et al, 2020;Keimeso et al, 2020;Khamphasan et al, 2020;Onejeme et al, 2020;Patil et al, 2020;Scaria., 2020;Upreti et al, 2020;Yu et al, 2020;Abdulazeez et al, 2021;Maphumulo et al, 2021;Nyombayire et al, 2021;Riacheet al, 2021) and very few authors ( Dermail et al, 2020;Ravikesavan et al, 2020;Vanipraveena et al, 2021) pertaining to sweet corn. Keeping up with the demand of sweet corn in the market, development of sweet corn hybrids is need of the hour.…”