Effect of Salt Stress on Proline Accumulation in Various Varieties of Maize

Abstract

                        Maize is third largest crop in the world and in Pakistan it is fourth most cultivated crop. Soil salinity is a severe danger to its production worldwide. Modern molecular biology tools are now used to elucidate the process of salt stress resistance and how particular stress-related gene expression is exploited to create crops that can withstand stress. In maize, when the salt stress increases in the soil it leads to osmotic imbalances and result in more proline accumulation in plant because it is the protector response against osmotic pressure. Objectives of this study were to observe the effect of salt stress on two different seed varieties of maize and to determine the proline content before and after the salt stress. The current study was conducted at National Institute for Genomic and Advanced Biotechnology (NIGAB), National Agriculture research Center (NARC) Islamabad. In the present study the effect of NaCl at different concentrations (i.e 0 mM, 50 mM and 80 mM) was observed on two maize cultivars (NARC-white and Agaiti-2002) at early growth stages. Statistical analysis was done by using Statistic 8.1 software by using Completely Randomized Factorial Design (ANOVA). The results showed that both cultivars were salt resistant but Agaiti-2002 showed more salt resistance than NARC-white. Moreover, the proline accumulation is increased in all varieties and showed that Agaiti-2002 produces 14% more proline than NARC-white which retards the growth of maize plant due to salinity. The study has shown that advanced maize breed is more resistant to salt stress and found that Agaiti-2002 variety is more resistance to salt stress than NARC-white. The approval of these breed as commercial varieties will increase genetic diversity in terms of salt resistance.