การผสมข้ามชนิดและการถ่ายทอดลักษณะด้วยวิธีการผสมกลับในพริก

Abstract

Chili is one of the world's most economically and agriculturally important vegetables in terms of cultivation area, production, commercial value, and consumption. They were classified into the genus Capsicum which is a highly diverse genus. Thirty eight species are currently recognized, 5 of which are domesticated: C. annuum L., C. chinense Jacquin, C. frutescens L., C. baccatum L. and C. pubescens Ruiz & Pavon. C. annuum produces solitary flowers, while C. chinense produces multiple flowers per node. C. frutescens shows 2 flowers per node. Interspecific hybridization is the only way to transfer genes that control multiple flowers and their transfer from C. chinense to C. annuum and C. frutescens to increase fruit yield. Forty four varieties of chilies were grown for selection. Ten varieties were selected. They were classified into 3 species; C. annuum, C. chinense and C. frutescens. It was demonstrated that viability and germination of pollen of all varieties were viable and there was no differences among the varieties. However, % seed germination was significantly different. Bhut Jolokai showed the lowest% and CA1449-6-19, F-3-8 and M1116 showed the highst % seed germination. However, M1116 showed the lowest% of fruit setting and F-3-8 and Bhut Jolokai showed the highst %. Interspecific hybridization and backcrossing was observed among C. annuum, C. chinense and C. frutescens. Chili plant height, bush width, fruit width, fruit length, and average fruit of all 10 varieties significantly different. Among the F1 hybrids, CA1449-6-10-1 × 35-5-3-1 demonstrated the highest fruit width which was significantly different from other F1 hybrids, BC1F1, BC2F1 and most of the parents. Among the F1 hybrids, PJ07-1 × Bhut Jolokai-1 demonstrated the highest fruit length which was significantly differently longer than other F1 hybrids, BC2F1 the parents and most of BC1F1. Among the F1 hybrids, M1116-2 × PJ07-1 demonstrated the highest average fruit weight which was significantly differently higher than most of BC1F1, BC2F1, the parents. However, the average fruit weight was significantly different higher and lower than other F1 hybrids and the parents. Interspecific hybridization between C. annuum × C. chinense did not increase fruit weight per plant of C. annuum. However, the hybridization between C. chinense × C. frutescens increased fruit weight per plant of variety JD01-2. The hybrid 35-5-3-1 × Bhut Jolokai-3 and 35-5-3-2 × Bhutjolokai-1 increased fruit weight per plant of 35-5-3-1, eventhough, the fruit size was decreased. Interspecific hybridization between C. frutescens (35-5-3-1) with many varieties of C. annuum. It increased fruit weight per plant, higher than the parents and decreased average fruit weight lower than the parents. Good potential hybrids were 35-5-3-1 × F-3-8-2, 35-5-3-1 × PJ07-2, 35-5-3-1 × PJ05-2, 35-5-3-3 × J-10-3-2 and 35-5-3-2 × CA1449-6-10-2. 35-5-3-1 was the best parent among the group. Molecular marker technique, start codon targeted (SCoT), was used to observe the bandings of PJ07-1 × Bhut Jolokai-2 and its parents. The bandings of both parents and extra one were demonstrated in the agarose gel electrophoresis of PJ07-1 × Bhut Jolokai-2.