Annual Wheat Newsletter

Pakistan falls into arid and semi-arid regions of climatic conditions. Areas receiving a rainfall less than 100 to 250 mm to less than 500 mm are called semi-arid lands. These lands constitute about 88% of the country’s total geographic area of 79.6 x 106 ha and are prone to occasional drought resulting in low or no production. Drought is one key constraint that influences our national wheat yield. For breeding targets to be achieved, unique diversity is paramount. Synthetic hexaploid (SH) wheats may provide this diversity. Earlier, international screening under reduced irrigation conditions led to the identification of 53 SH wheats. Twenty-seven of these SH wheats have been tested now under Pakistani conditions for the first time along with three standard, global, drought-tolerant check wheat cultivars. The germ plasm evaluation was done under in vitro conditions by giving a drought stress of 30% PEG to the SH wheats and checks. Their proline, protein, sugar, chlorophyll, and SOD content were assessed by comparing with the control lines. We observed that the degree of drought tolerance varied in all 27 SH wheats and thr checks, because of their genetic variability. SHDR 17, SHDR 18, SHDR 45, SHDR 46, SHDR 49 SHDR 50, SHDR 51, SHDR 52, and SHDR 53 were drought tolerant, whereas three lines, SHDR 29, SHDR 43, and SHDR 21, were sensitive. introduction. Drought stress remains an ever increasing problem that severely limits crop production by preventing crop plants from expressing their full genetic potential (Rampino et al. 2006; Karmer 1980) and can cause yield losses greater table 22. Means for SOD contentof different wheat genotypes tested for drought in vitro (the LSD (0.05) of interaction (G×T) = 8.624, LSD (0.05) of genotypes (G) = 6.098, and LSD (0.05) of treatments (T) = 1.200, genotypes with different letters are significantly different). genotype control drought mean genotype control drought mean F4 719 30.13 C-T 39.69 B-D 34.91 B-D Landrace 7 17.65 X-b 24.69 K-a 21.17 L-Q F4 786 28.70 D-X 32.18 C-P 30.44 D-J Landrace 8 18.87 U-b 20.80 Q-b 19.84 M-R F4 826 37.24 B-H 38.96 B-F 38.10 A-C Landrace 9 30.39 C-T 32.20 C-P 31.29 C-I F4 834 21.81 N-b 26.10 I-Z 23.96 I-Q Landrace 12 33.82 B-M 34.50 B-L 34.16 B-E F4 841 26.94 H-Y 34.44 B-L 30.69 D-J Landrace 14 21.25 O-b 29.43 D-V 25.34 G-P F4 883 20.14 Q-b 25.30 J-a 22.72 K-Q Landrace 15 20.83 Q-b 21.75 N-b 21.29 L-Q F4 922 30.59 C-S 39.07 B-E 34.83 B-D Landrace 16 27.57 G-Y 32.57 C-N 30.07 D-K F4 925 20.85 Q-b 21.12 P-b 20.98 L-R Landrace 17 19.75 S-b 19.83 R-b 19.79 M-R F4 1992 32.47 C-N 36.48 B-I 34.48 B-E Landrace 18 32.91 B-N 35.12 B-K 34.01 B-F F4 2011 39.54 B-D 40.53 A-C 40.03 AB Landrace 20 13.39 b 14.31 ab 13.85 R Inqilab-91 25.41 I-a 27.87 G-Y 26.64 F-N Landrace 24 28.41 E-X 36.44 B-J 32.43 C-G Baviacora 32.11 C-P 32.59 C-N 32.35 C-G Landrace 26 24.75 K-a 26.70 H-Y 25.72 G-O Opata M 85 23.78 L-b 26.54 H-Y 25.16 G-P Landrace 27 25.33 I-a 26.61 H-Y 25.97 G-O Sitta 19.57 S-b 25.67 I-Z 22.62 K-Q Landrace 28 16.74 Y-b 20.67 Q-b 18.70 O-R Suleman 96 19.19 T-b 22.47 N-b 20.83 L-R Landrace 29 27.31 G-Y 29.50 D-U 28.41 D-L Weebill 18.26 V-b 20.22 Q-b 19.24 N-R Landrace 30 23.86 L-b 25.33 I-a 24.60 H-P Nesser 25.04 K-a 25.82 I-Z 25.43 G-P Landrace 31 19.51 S-b 28.17 E-X 23.84 I-Q Dharwar 28.98 D-W 29.12 D-V 29.05 D-K Landrace 32 22.98 M-b 23.76 L-b 23.37 J-Q Zarghoon 32.67 C-N 34.78 B-L 33.73 B-F Landrace 33 17.89 W-b 18.80 U-b 18.35 O-R Chakwal 86 31.08 C-Q 32.33 C-O 31.71 C-H Landrace 34 24.76 K-a 29.28 D-V 27.02 E-M Margalla 99 38.33 B-G 43.37 AB 40.85 AB Landrace 35 14.98 Z-b 18.78 U-b 16.88 QR Marwat 37.48 B-H 49.37 A 43.43 A Landrace 36 25.06 K-a 30.98 C-R 28.02 D-L Landrace 1 23.67 L-b 31.18 C-Q 27.42 D-M Landrace 37 27.92 F-Y 34.82 B-L 31.37 C-I Landrace 2 15.24 Z-b 20.55 Q-b 17.89 P-R Landrace 39 24.55 K-a 26.83 H-Y 25.69 G-O Landrace 3 17.49 X-b 27.94 F-Y 22.72 K-Q Landrace 40 19.43 S-b 30.98 C-R 25.20 G-P Landrace 5 22.02 N-b 29.37 D-V 25.70 G-O Mean 25.07 B 29.13 A