Executive Summary : | Melons of Cucurbitaceous family are one of the important horticultural crops of economic and nutritional importance. In melon improvement, the snap melons of Indian origin have played a significant role in providing disease resistance genes for major diseases throughout the world. Linkage maps are developed using Snapmelon as one of the parents and QTLs have been mapped for disease resistance (majority for powdery mildew) genes but for fruit characters of Snapmelon the information is scanty. Though Snapmelon could be a potential crop for large scale cultivation as in Kerala state, where snapmelon is being used in juice industry, very short post-harvest life and fruit bursting limits its cultivation, storage and transportation. There is a necessary to breed non-cracking or splitting type snapmelon varieties and to understand the inheritance of melon fruit bursting/cracking. Snapmelon from the Karnataka state is an unexplored germplasm for breeding. Our previous studies have shown that it is multiple diseases resistant and can cross freely with other melons. Snapmelon crosses easily with other melons like Kashi Madhu of chandalak type. Kashi Madhu is one of the Indian desert purpose melons with superior fruit and nutritional qualities as observed in our previous studies. Through crossing Snapmelon and Kashi Madhu of different botanical group of melons and developing their recombinant inbred lines through single seed descent method gives an opportunity to create genetic variation and selection of superior lines or transgressive segregants. Genotyping-by-sequencing has been developed as a rapid and robust approach in marker discovery and genotyping. DNA bulk from extreme phenotypes like bursting fruit type and non bursting fruit type from RILs along with parents will be sequenced at F5 generation. Next generation sequencing (NGS) data analysis and identification of the potential single nucleotide polymorphism (SNPs) from the raw sequence information will be done to detect high quality SNPs. Map will be constructed to identify QTLs related to fruit bursting and other traits. Transcriptome analysis of fruits from contrasting parents/RILs will be carried out. The phenotyping and genotyping of RIL and mapping the markers give marker- QTL/gene relationship and helps in locating QTL position on linkage groups. The results of this study can help in better understanding the inheritance of fruit bursting/cracking and other fruit quality traits of snapmelon. |