Identification of the adaptable Capsicum annuum L. varieties for low water availability under in vitro conditions

Abstract

Capsicum annuum L. (chilli) is a dominant crop cultivated in Kalpitiya peninsula where soil water availability is a major constraint. Introduction of commercial vegetable varieties adaptable to low water availability is a solution. Thus, 11 commercial chilli varieties including five exotic and six local varieties were screened using Polyethylene Glycol (PEG) 6000 supplemented Murashige and Skoog (MS) media to induce drought under in vitro conditions. Three PEG levels 20, 40 and 60 g/L were tested against the control medium without PEG. Experiment was repeated two times with 60 seeds per treatment. Seed germination and the early growth parameters of root and shoot length, root, and shoot dry weight and number of leaves after 30 days of culturing were assessed using ANOVA. Over 80% seed germination was recorded in five varieties namely Kodian Hot, Lanka Hot, Deluxe, Vijaya and MICHY1, where a significant drop was observed only at 60 g/l PEG. In all varieties the growth parameters showed a decreasing trend with increased PEG levels. Even though variety Deluxe showed the best performance in control, a significant decrease was observed with increased PEG levels in all the parameters. However, some varieties including Vijaya in shoot length, root dry weight and number of leaves, MI3 in root dry weight and number of leaves, Sera234 in root dry weight, MICHHY1 in shoot length and MICHHY2 and MI2 in shoot dry weight did not show a significant difference among all the PEG levels over the control. Vijaya in shoot dry weight and root length, Sera234 in shoot length, shoot dry weight and root length, MI3 in shoot length and root length and Lanka Hot in number of leaves showed a comparable growth in 0-40 g/l PEG levels. In Kodian Hot for four parameters and Galkiriyagama, Lanka Hot and MICHHY1 for three parameters showed a comparable performance in 0-20 g/l PEG supplemented media. Based on the results Vijaya, Sera234 and MI3 were selected as the adaptable varieties for low water availability