Performance of Some Bread Wheat Genotypes Under New Valley Condition

This study aimed to assess the performance of six bread wheat genotypes introduced by a national wheat research program. These genotypes were sown at four planting dates 20 th October, 10 th November (recommended), 30 th November and 20 th December during two winter seasons of 2019/2020 and 2020/2021. The separate experiments were arranged in a randomized complete block design with four replications in each environment. The combined analysis of variance showed that mean squares due to environments were highly significant for number of spikes m -2 , 1000-kernel weight as well as grain yield (ard/fed) this result indicated that the studied genotypes exhibited different effect from environment to other. Mean squares due to genotypes x environments were highly significant for all studied traits except number of spikes/m 2 . Parameters of phenotypic stability indicated that wheat genotypes Giza 171 and Misr3 are considered a stable verity for studied environments for grain yield (ard/fed), respectively, where had a coefficient of regression don’t significantly differ from one and less amount of S 2 di and adapted.


INTRODUCTION
Wheat (Triticum aestivum L.) is the most important cereal crop and significant staple food in the world.Its total cultivation area in 2021was 244.3 million hectares produced 907.8 million tons.Egypt was involved in these values with cultivation area 1.39 million hectares (3.32 million fadden) produced 9.0 million tons.In spite of this, Egypt is considered one of the biggest wheat importers, imports annually around 5.77 million tons where, the annual consumption of wheat is 14 million tons (FAOSTAT, 2021).In addition, the gap between production and consumption is increasing due to population growing.For this reason, cultivated areas and productivity should be increased to reduce the gap.This can be achieved by developing high yielding varieties and cultivating wheat in newly reclaimed soils.Evidently, the main production constraints of such areas are the low fertility and moisture deficiency of the sandy soils with the ensuring drought and heat stress Yousef (2009).
To improve this crop, breeders used the phenotypic stability for selection of wheat varieties in their breeding programs.Narrowing the adaptation of cultivars aim to maximize yield in particular areas by exploiting genotype (G) × environment This study aims to examine the performance and stability of grain yield of six bread wheat genotypes under New Valley conditions.

MATERIALS AND METHODS
The New Valley desert has been defined with hot and dry climate with temperatures is ranging in winter between 20 to 35 o C, and in summer rise between 40 to 45 degrees, with extremely rare annual rainfall (Table 1).
Six bread wheat genotypes were tested at the experimental farm, Agricultural Research Station of El-Kharga, the New Valley under four planting dates 20 th October, 10 th November (recommended), 30 th November and 20 th December during two winter seasons of 2019/2020 and 2020/2021.The pedigree and origin of the studied bread wheat genotypes are presented in Table 2.
The experiment was laid out in a randomized complete block design (RCBD), with four replications for each planting date.The plot size was 3.6, each plot consisted of 6 rows, 3 m long and 20 cm apart.Wheat grains were hand drilled at the rate of 70 kg fed -1 .All agricultural practices were adopted as recommended for wheat production over the two growing seasons.
Analysis of variance was conducted according to Gomez and Gomez (1984) using SAS software (Version 9.2).Stability parameters were estimated by the methods described by Eberhart and Russell (1966) from the regression analysis.These parameters i.e., regression coefficient (bi) and deviations from regression (s 2 di) were estimated.

Analysis of variance
Combined analysis of variance revealed highly significant differences among environments and genotypes for most studied traits (Table 3).These results explained the effect of climatic differences due to planting dates with growing seasons.Genotyped Showed different responses to different environmental conditions that point out the importance of the evaluation of genotypes under different environments to identify the best genotype for a certain environment.
The interaction of environments x genotypes was highly significant effect for 1000-kernel weight and grain yield, and insignificant effect was showed for number of spikes m -2 , indicating the different influences of climatic conditions on planting dates.and the mean performance ( X � ) of the individual genotypes are presented in Table 6.

Number of spike/m 2
There was significant genotypic variation for number of spike/m 2 among the 6 bread wheat cultivars used in the stability analysis.The results showed that Sakha 95 had the highest mean number of spikes/m 2 (457.53spikes/m 2 ), while the lowest mean number of spikes/m 2 was obtained from Giza 171 (363.69 spikes/m 2 ) with an average 417.57spikes/m 2 (Table 6).According to Eberhart and Russell (1966), two cultivars (Sakha 95 and Masr 3) were stable due to their bi's and S 2 di's did not differ from a unit and the zero, respectively.Out of them, one cultivar (Sakha 95) have the highest number of spikes compared with the grand mean over environments conditions.Moreover, Gemmiza 12 and Shandwel 1 performed consistently better in favorable environments because the regression coefficient (bi) was more than one plus showing the highest mean number of spikes compared with mean over all cultivars.Meanwhile, Sids 14 and Giza 171 was relatively better in stress environments because bi was less than one (bi<1) (Table 6 and figure 1).Means of 1000 kernel weight (g) ranged from 46.96 g for Shandaweel 1 to 53.51 g for Giza 171 with an average 49.46 g.Three cultivars (Sids 14, Masr 3 and Giza 171) were stable under favorable environments because the regression coefficient (bi) was more than one and S 2 di was insignificant from zero, one of them (Giza 171) had a high mean of performance when compared with the mean overall cultivars.Meanwhile, Gemmeiza 12, Shandweel 1 and Sakha 95 was relatively better in stress environments because bi was less than one (bi<1) (Table 6 and figure 2).The studied cultivars appeared to have a wide range of variability in average grain yield over environmental condition (two growing seasons and four planting dates) as shown in Table 6 and fig performance and has a major role in assessment of performance stability of the breeding materials Salous (2019).

Fig
Fig. 1.Present graphically the relationships between the stability parameters (bi) and its mean performance of each genotype for number of spike m -2

Fig. 2 .
Fig. 2. Present graphically the relationships between the stability parameters (bi) and its mean performance of each genotype for 1000-kernel weight . 3. Mean grain yield ranged from 13.32 ard./fed.(Masr 3) to 17.85 ard./fed.(Sids 14) with an average of 15.34 ard./fed..According to Eberhart and Russell (1966), three cultivars (Gemmeiza 12, Shandweel 1 and Giza 171) were stable over all the studied environments because the regression coefficient (bi) of these cultivars closed one and the deviation from regression (S 2 di) was insignificant from zero.one of them (Gemmeiza 12) had a high mean of performance when compared with the mean overall cultivars.Moreover, Sids 14 performed consistently better in favorable environments because the regression coefficient (bi) was more than one plus showing the high yield.Meanwhile, Sakha 95 was relatively better in stress environments because bi was less than one (bi<1) plus showing the high yield compared with mean over all cultivars.These results are in line with those reported by Seleem (2007) and Ali et al. (2020).

Fig. 3 .
Fig. 3. Present graphically the relationships between the stability parameters (bi) and its mean performance of each genotype for grain yield (ard fed -1 )

Table 2 . Pedigree, selection history and origin of the six bread wheat genotypes evaluated at this study No Genotypes Pedigree and selection history Origin
1 Gemmeiza 12 OTUS

Table 3 . Combined analysis of variance for studied traits of 6 bread wheat genotypes evaluated at
NVJAS. 3 (10)

Table ( 5): Stability analysis for number of spikes m -2 , 1000-kernel weight and grain yield of 6 bread wheat varieties evaluated at 8 environments under New Valley condition
,** indicate significant differences at 0.05 and 0.01 levels of probability, respectively. *

Table 6 . Stability parameters of number of spikes m -2 , 1000-kernel weight and grain yield of 6 bread wheat genotypes evaluated at 8 environments under New Valley condition Genotypes No of spike m -2 1000-kernel weight (g) Grain yield (ard fed -1 )
* indicate highly significant differences at 0.01 level of probability. *