Genetic variability studies on bread wheat (Triticum aestivum L.) genotypes

Abstract

Thirty bread wheat genotypes were tested to assess the genetic variability, among studied genotypes using alpha-lattice design at Tongo sub-center of Assosa Agricultural Research Center and Kulumsa Agricultural Research Center in 2015. Analysis of variance revealed that there were statistically significant differences among the genotypes for most of the traits at individual and across locations. From the combined analysis of variance, significant (p≤0.05) effect due to location, varieties and G×E was observed for most of the traits. The varieties showed wider variability in mean grain yield of 1284.4-3788.7 kg ha-1 , 2588.3-4683.3 kg ha-1 and 1936.4-4095.6 at Tongo, Kulumsa and across location, respectively. Moderate PCV values (>10%) were obtained for grain yield, 1000 kernel weight, harvest index, tillers per plant and spikes per plant at individual location and across location including days to heading, above ground biomass yield, spike length and kernels per spike at Tongo and above ground biomass yield at Kulumsa. Similarly, moderate GCV values (>10%) were obtained for grain yield, 1000 kernel weight, tillers per plant and spikes per plant at individual location including days to heading, harvest index and kernels per spike at Tongo and above ground biomass yield at Kulumsa. Lower (<10%) was obtained for all traits across location. High heritability estimates (>80%) were obtained for days to heading (86.0%) and days to maturity (85.1%) at Tongo and days to heading (86.2 and 82.69%) and spikes length (80.1 and 82.85%) at Kulumsa and across location. But relatively high genetic advance (>20%) was obtained for grain yield (28.5%) and harvest index (24.3%) at Tongo. Moderate genetic advance (10-20%) was observed for 1000 kernel weight, spikes length and days to heading at individual location and across location including spikelets per spike, tillers per plant, above ground biomass, spikes per plant and plant height at individual location. Generally, it has been observed the presence of variability among the genotypes, heritability in the tested traits of the genotypes studied. Hence, Selection and hybridization on those genotypes based on the trait with high GCV, heritability and genetic advance can be recommended for farther yield improvement of bread wheat at respective location.

Assessment of genetic variability among bread wheat genotypes for agronomic and morphological traits under optimum and stress condition

“…The result was in agreement with the previous findings of Dargicho et al (2015b) and Jamil et al (2017) Low GCV coupled with low PCV values were noted for days to heading, days to maturity, grain filling period, harvest index, plant height and number of spikelets spike -1 under optimum condition. The present result is in agreement with the finding of Alemu et al (2019) who reported low GCV and PCV values for days to heading, days to maturity, Harvest index, plant height and spikelets spike -1 . A low GCV value was recorded for number of kernels spike -1 and thousand kernel weight (Table 4).…”

“…Fifty genotypes exhibited mean performance superior to check (Fentalle-2) for thousand kernel weight. Different authors reported similar range of variations for spike length, spikelet spike -1 , number of kernels spike -1 and thousand kernel weight in their study (Gezahegn et al 2015;Dargicho et al 2015b;Alemu et al 2019;Ashebir et al 2020).…”

“…Four genotypes had mean performance higher than check (Fentalle-2), while twenty nine genotypes had mean performance lower than standard check (Kingbird) for harvest index. Wide ranges of variations were reported for biomass yield and harvest index in bread wheat previously by Dargicho et al (2015b), Girma (2018) and Alemu et al (2019).…”

“…Nine genotypes had mean values lower than standard check (Kingbird=3.22 t ha -1 ) for grain yield. Similarly, several authors reported wide range of variation in bread wheat for grain yield (Dargicho et al 2015b;Alemu et al 2019;Sohail et al 2019;Ashebir et al 2020).…”

“…Forty five genotypes had mean value shorter than check (Fentalle-2) for plant height and nineteen genotypes had low number fertile tiller plant -1 than standard check (kingbird). Girma (2018), Alemu et al (2019) and Mihratu et al…”