JIA-2019-11

2485 Hafiz Ghulam Muhu-Din Ahmed et al. Journal of Integrative Agriculture 2019, 18(11): 2483–2491 further investigated for correlation and analysis (Ogunbayo et al . 2005). 3. Results A total of 105 spring wheat genotypes were screened in the green house using factorial under completely randomized design. Highly significant differences were exhibited among accessions under normal and drought conditions for all studied traits (Table 1). The summary statistics of five seedling traits (Table 2) and means performance of 105 genotypes under both conditions. All the studied characters exhibited fluctuations in mean value under drought conditions for most of the genotypes. 3.1. Morphological attributes Recorded data for root length of wheat seedling varied significantly, ranged from 7.22 to 23.00 cm under normal condition while in water stress condition ranged from 5.31 to 17.65 cm as shown in Table 2. The genotypes G11 and G61 had the maximum root length 23.00 and 17.65 cm under normal and drought conditions, respectively, while the lowest root length with the mean values of 7.22 and 5.31 cm observed in G98 and G105 under normal and stress conditions respectively as displayed in Fig. 1. Shoot length of wheat is an important character and is also affected by drought stress. The phenotypic behavior of any character is due to the environment and genotype (G×E) interaction. Shoot length varied significantly, ranging from 13.16 to 29.17 cm under normal and under drought conditions ranging from 11.00 to 25.19 cm (Table 2). The G105 and G3 had the maximum shoot length 29.17 and 25.19 cm under normal and stress conditions, respectively, while the lowest shoot length with the values of 13.16 and 11.00 cm was observed in G32 and G51 under normal and drought conditions respectively (Fig. 1). 3.2. Photosynthetic attributes All studied wheat genotypes behaved differently in terms of seedling’s photosynthetic pigments against drought conditions. Chlorophyll a for studied genotypes varied significantly ranging from 1.37 to 1.64 mg g –1 under normal condition and under water stress conditions ranged from 1.35 to 1.62 mg g –1 as shown in Table 2. The G21 and G6 had the maximum chlorophyll a with the values of 1.64 and 1.62 mg g –1 under normal and stress conditions, respectively, while the lowest chlorophyll a with the values of 1.37 and 1.35 mg g –1 observed in G91 and G105 under normal and stress conditions, respectively (Fig. 2). Data collected for chlorophyll b for all genotypes (Table 2) varied significantly ranging from 0.46 to 0.64 mg g –1 under normal environments while under drought conditions ranged from 0.39 to 0.57 mg g –1 . The genotypes G39 and G26 had the maximum chlorophyll b with the values Table 1 Analysis of variance (ANOVA) mean square of 105 spring wheat genotypes at seedling stage under normal and drought conditions Trait Genotype (G) Environment (E) G×E Error Total SoV/ df 1) 104 1 104 420 629 Root length 61.15 ** 1 749.07 ** 6.86 ** 3.13 Shoot length 39.51 ** 3 792.76 ** 8.55 ** 2.1 Carotenoid 0.00669 ** 3 792.76 ** 8.55 ns 2.1 Chlorophyll a 0.02483 ** 0.01939 ** 0.00074 ns 0.00151 Chlorophyll b 0.00701 ** 0.76442 0.00007 ** 0.0005 1) SoV, sources of variation; df , degree of freedom. ** , significance at P =0.01; ns, non significant. Table 2 Mean summary statistics of five seedling traits of 105 spring wheat genotypes under normal and drought conditions Trait Environment Minimum Maximum Mean SD Root length (cm) Normal 7.22 23.00 11.66 4.005 Drought 5.31 17.65 8.32 2.542 Shoot length (cm) Normal 13.16 29.17 22.69 2.965 Drought 11.00 25.19 17.79 2.755 Carotenoid (mg g –1 FW) Normal 0.32 0.49 0.40 0.034 Drought 0.24 0.41 0.33 0.034 Chlorophyll a (mg g –1 FW) Normal 1.37 1.64 1.48 0.066 Drought 1.35 1.62 1.47 0.065 Chlorophyll b (mg g –1 FW) Normal 0.46 0.64 0.54 0.034 Drought 0.39 0.57 0.47 0.034