Genetic diversity and relationship assessment of Lilium lancifolium × Asiatic hybrid ‘Chianti’ progeny by ISSR markers

In Lilium crossing, old cultivars and wild germplasm have been utilized as valuable sources of genetic material for the development of new cultivars. The aim of the present study was to examine the genetic variation, diversity, and phylogenetic relationship in the F₁ and BC₁ progeny in the Lilium lancifolium × Asiatic hybrid ‘Chianti’ by ISSR analysis. The primers yielded a total of 69 highly reproducible ISSR bands. The results indicated a range of Nei’s genetic diversity index (He) between 0.2913 ± 0.17 and 0.3932 ± 0.16. The Shannon’s information index (I) showed the highest (0.5650 ± 0.14) and lowest (0.4441 ± 0.22) values for primers ‘FBLISSR-10’ and ‘FBLISSR-8’, respectively. A genetic similarity matrix showed that F₁ hybrids exhibited greater genetic similarity (0.6087 and 0.6667) than BC₁ hybrids, except BC_1-2 (0.6232) and BC_1-10 (0.6377) in relation to the L. lancifolium parent. Among the progeny, genetic distance expressed a significant variation ranging from 0.2638 to 0.8001. The closer phylogenetic relationship between L. lancifolium and BC_1-2 (group 1) and BC_1-10 (group 2), compared to other backcross progeny, revealed that these hybrids extensively inherited the L. lancifolium genome to build their genetic structure. This genetic distance, similarity, and relationship among hybrids helped in identifying the variation in the genetic make-up of the progeny. ISSR markers discriminated the closely related and distant progeny from the parental genotypes to understand the crossing effect on the genetic structure of the progeny.