Estimates of Heterosis, Combining Ability and Correlation for Yield and its Components in Bread Wheat

Abstract

In order to realize the heterosis, general and specific combining ability of wheat, 28 crosses were synthesised in a 8 × 8 by using half diallel mating system, without reciprocals. Analysis of heterosis over mid parents (MP) as well as better parents (BP) and combining ability were conducted for yield and its contributing traits. The experiment was conducted in 2011-2012 and 2012-2013 seasons at the Experimental Farm of Faculty of Agriculture, Sohag University, Egypt. Heterosis was estimated for grain yield per plant revealed maximum heterosis over the mid parents (68.58% and 81.47%) for the crosses P 5 × P 8 and P 5 × P 6, followed by harvest index (53.32%), No. of spikes per plant (33.38%), biological yield per plant (30.71%), spike length (17.29%), 1000 kernel weight (15.13%),grain weight per spike (14.38%) and plant height (5.96%) for the crosses P 7 × P 8 , P 5 × P 8 , P 4 × P 5 , P 4 × P 8 , P 3 × P 4 , P 1 × P 3 and P 7 × P 8 , respectively. The maximum heterobeltiosis was recorded for grain yield per plant (82.56% and 49.3%) for the crosses P 5 × P 8 and P 5 × P 6, followed by harvest index (40.12%), biological yield per plant (28.29%), No. of spikes per plant (16.9%), 1000 kernel weight (14.05%), grain weight per spike (12.9%), spike length (9.53%) and plant height (4.76%)%) for the crosses P 5 × P 8 , P 5 × P 6 , P 2 × P 5 , P 3 × P 4 , P 1 × P 3 , P 2 × P 6 , and P 5 × P 7 , respectively. The results indicated significant differences among the parents for general combining ability and crosses for specific combining ability for all studied traits, which indicated the importance of both additive and non-additive gene effects for these traits. General combining abilities were higher than those of specific combining abilities, then the GCA/SCA ratios were more than unity indicating the prepondorance of additive gene effect which have considerable roles in the inheritance of these traits. In general, The genotypes of P 5 ( Sonora 64 ) confirmed to be good general combiner for plant height, No. of spikes / plant, 1000 -kernel weight, grain weight / spike, biological yield / plant, harvest index, grain yield / plant , and P 4 ( Sahel 1 ) for plant height, spike length, No. of spikes / plant, 1000 -kernel weight, harvest index, grain yield / plant. The crosses P 6 × P 7 , P 5 × P 6 , P 7 × P 8 , P 5 × P 8 , P 2 × P 6 , P 4 × P 8 , were the best specific combiners for grain yield / plant and most of yield components. Grain yield had strong positive correlation with harvest index (0.85), biological yield per plant (0.65) and 1000 -kernel weight (0.59).

Heterosis for grain yield and its attributing traits in bread wheat (Triticum aestivum L.)

“…Out of 32, 11 hybrids registered significant and positive heterosis over standard check (Table 3). Similar findings were also reported by earlier worker Motawea (2017).…”

Combining Ability for Grain Yield and Some Agronomic Traits in Diallel Crosses of Bread Wheat Under Nitrogen Stressed Conditions

“…Such result indicates that inheritance of these traits was mainly controlled by non-additive gene effects under such conditions of nitrogen fertilization. These results are supported findings of (Motawea 2017;Farooq et al 2019;Kutlu and Sirel 2019). Mean squares for interactions of either GCA or SCA with nitrogen levels were highly significant for the all studied characters except of GCA x N levels for grain yield/plant, revealing the existence of sensitivity of both types of gene action to variation in nitrogen treatments.…”

“…These estimates can then be used to draw conclusions about the genetic systems controlling grain yield and the other important characters as well as the best breeding strategy to be used to improve them. Several researchers found that the additive gene action was important in the inheritance of grain yield (Motawea 2017), plant height (Nathan and Moubarak 2016) and number of spikes/plant (Kamaluddin et al 2007). On the other hand, other investigators mentioned that the non-additive genetic effects played the important role in the inheritance of grain yield (Farooq et al 2019;El-Said 2018;Ayoob 2020) and spike length (El-Hosary et al 2012; Kutlu and Sirel 2019).…”

Combining ability for quantitative traits related to productivity in durum wheat

“…It should be noted that the main structural elements of yield -spike length and in most cases thousand kernels weight are controlled by additive gene ef fects. Preponderance of additive gene effects in inheritance of plant height has been reported by a number of other researchers (Yao et al, 2011;Motawea, 2017;Ali et al, 2018;Hassan et al, 2018;Rajput, Kandalkar, 2018;Singh et al, 2018;Talha et al, 2018;Sharma et al, 2019;Ayoob, 2020); for spike length (Kandil et al, 2016;Motawea, 2017;Parveen et al, 2018;Rajput, Kandalkar, 2018;Sadeghzadeh-Ahari et al, 2018;Singh et al, 2018;Farooq et al, 2019;Sharma et al, 2019;Khaled et al, 2020;Shamsabadi et al, 2020); for thousand kernels weight (Hannachi et al, 2017;Motawea, 2017;Ali et al, 2018;Hassan et al, 2018;Ali, 2019;Amin, Towfiq, 2019;Farooq et al, 2019;Khokhar et al, 2019;Sharma et al, 2019).…”

“…ГЕНЕТИКА РАСТЕНИЙ / PLANT GENETICS et al, 2020); for thousand kernels weight (Topal et al, 2004;Akinci, 2009;Desale, Mehta, 2013;Brahim, Mohamed, 2014;Motawea, 2017;Ali et al, 2018;Hassan et al, 2018;Ali, 2019;Khokhar et al, 2019;Sharma et al, 2019).…”