Salinity tolerance and site of K + accumulation in four maize varieties grown in Khyber Pakhtoonkhwa region of Pakistan

Abstract

Crops face different types of biotic and abiotic stresses. Among abiotic stresses, salinity is very harmful and adversely affects the yield and production of crops. In Pakistan, maize is the third most important cereal crop after wheat and rice. In this research work, salt stress was applied to four maize varieties. The experiment was conducted in glass house. The effect of salinity on some physiological parameters that is, fresh and dry biomass of whole plant, above ground part and root of maize (Zea mays L.) was observed and the site of plant which accumulates K+ was determined. Five salinity levels of 30, 60, 110, 160 and 240 mmol each for NaCl and KCl were checked. The results showed that NaCl had significant effect on fresh and dry whole plant biomass, above ground biomass and root biomass. KCl had significant effect on whole plant fresh biomass and above ground dry biomass while its effect on above ground, root fresh biomass, whole plant and root dry biomass was insignificant. The combined effect of NaCl and KCl was also insignificant on fresh as well as dry biomass. With increasing salinity however, the cultivar Azam followed by Pop-2006 were the most tolerant to salinity. Contrarily, Pahari and Sarhad white were the least salinity tolerant varieties. Flam photometric analysis indicate that K+ accumulates in roots and above ground biomass (shoot), accumulation is more in the shoot than in the root. Azam and Pahari cultivars accumulated less K+ than Pop-2006 and Sarhad white. Key words: Maize, salinity, stress, Pakistan, biomass.