Selection indices for identifying heat tolerant of maize (Zea mays)

Drought and heat stress have become the most prevailing problems for maize (Zea mays L.) crop production. Therefore, development of tolerance has an essential goal in a breeding programme. Hence, experiment was conducted at Punjab Agricultural University, Ludhiana, to identify tolerant DH lines during spring season, 2016 2017. A total 32 were evaluated under non-stress conditions. Five indices such as Tolerance Index (TOL), Mean Productivity (MP), Geometric (GMP), Stress Susceptibility (SSI) (STI) calculated based on grain yield (Ys) conditions (Yp). Grain condition showed negative significant association with TOL SSI while positive correlation MP, GMP STI. Similarly, non TOL, Based two years data using STI, line DH_4_23 DH_4_47 found be tolerant. These may used potential source can further