EFFECT OF SALT STRESS ON SEED GERMINATION AND EARLY SEEDLING GROWTH OF SELECTED SPECIES OF GREEN CHILI (Capsicum) SPECIES

Abstract

Salinity is a major and increasing problem worldwide that needs to be addressed in order to increase agricultural production. The experimental materials were five selected green chili species, such as Capsicum annuum, Capsicum frutescence, Capsicum chinense, Capsicum baccatum, and Capsicum pubescence and four NaCl concentration levels (0, 60, 120 and 180mM) for laboratory and greenhouse experiments. The experimental design was a completely randomized design in factorial combination with three replications. The following parameters such as, germination percentage, seedling shoot length, seedling root length, seedling root dry weight and number of branches per plant, shoot fresh weight and root fresh weight under greenhouse experiments were evaluated. All obtained data for germination and early seedling growth from laboratory and green house experiment were organized, analyzed, interpreted and computed statistically by one way analysis of variance (one way ANOVA) for the complete random design using SPSS version 20 windows and comparisons of means were made using list statistically significant difference (LSD).The analysis of the data showed that highly significant (p<0.05) variation among green chili variety, and treatments. At 180mMNaCl level Capsicum annuum (69.44%), exhibited the highest germination percentage while variety pubescence (46.2%) had the lowest value. In all the selected salinity levels, the highest seed germination percentage was observed in Capsicum annuum. Among the selected green chili species, Capsicum annuum (0.27cm) and Capsicum frutescence (0.16cm) species showed the highest shoot length in 180mMNaCl treatment. The number of branches per plant ranged from 4.22 to 9.11, 3.13 to 5.22, 3.12 to 3.83, and 16.0 to 11.00 in 60mM, 120mM, 180mM and control respectively. At the highest salinity level (180mM), all species had drastically reduced shoot length compared to the control group. In the greenhouse experiment mean seedling shoot fresh weight ranged from 0.06-0.10 in control, 0.05-0.09 in 60mM, 0.03-0.07 in 120mM and 0.02-0.04 in 180mM salt concentrations. In this study, the Capsicum annuum and Capsicum frutescence chili species showed the highest fresh root weight in all the treatments compared with the control group. According to results, Capsicum annuum and Capsicum frutescence have shown strong performance in all traits with different salinity levels. Therefore, these two species are considered as salt tolerant and have agricultural significance in future breeding of chili pepper for salt tolerance. This study was carried out in the laboratory as well as greenhouse, so further investigation in the field is recommended.