Genotypic and environmental interaction in advanced lines of wheat under salt-affected soils environment of Punjab

Wheat cultivars of diverse origin including approved varieties of different provinces of Pakistan i.e. Punjab, NWFP and Sindh were tested against different salinity levels in laboratory as well as in naturally saline fields in different ecological zones. Initially, 16 genotypes were studied for germination test at 6 different salinity levels ranging from 0-25 dS/m (2, 5, 10, 15, 20, 25, EC= dS/m). Then, out of 16 cultivars, 11 were studied for the relative growth rate at different levels of salinity and after their study in the laboratory, 9 genotypes were selected for testing in the naturally saline areas of Punjab province. Under germination percentage study, the varieties viz. Pasban-90, Sarsabz, Bakhtawar, 93032 and 933118 were less affected than other varieties. As regards the relative plant growth, varieties viz. Sarsabz, Bakhtawar, and Pasban-90 were tolerant to salinity at seedling stage while Inqlab was graded as sensitive to salt stress. Regarding field performance, significant differences were observed in the varieties grown under different saline environments and varieties x environment interaction. Varieties x environment (Lin) interaction was non significant while nonlinear interaction (pooled deviation) was significant. Based on overall yield performance, the Sarsabz variety produced the highest seed yield (4.37 T/ha) followed by Bakhtawar (4.24 T/ha) and Pasban-90 (3.93 T/ha). Regression coefficient values showed non significant differences to unity while standard deviation to regression showed significant differences to zero. These results indicated that the genotypes viz. Sarsabaz, Bakhtawar and Pasban-90 are better tolerant to saline environment as compared to others. The two genotypes, Marvi and 25219 had low regression values and can fit under stress environment.