Genetic diversity in Lentil (Lens culinaris Medikus subsp. culinaris)

Abstract

Lentil (Lens culinaris ssp. culinaris) important grain legume grown in rainfed areas of Central and Eastern India. The productivity of lentil in India is low in comparison to the global average. The main reason for low productivity is the narrow genetics base of cultivars and susceptibility to biotic and abiotic stresses. There is urgent need for broadening the genetics base utilizing Mediterranean germplasm. The present investigations were undertaken to identify the promising accessions for each trait, molecular characterization using SSR markers to understand the extent of genetic variability among the genotypes under study and characterization of lentil genotype for iron and zinc contents. 187 varieties/germplasm lines were characterized for 100 seed weight, no of pods/plant, filled pods/plant days to 50% flowering, duration of pod filling, days to maturity, primary branches, secondary branches, plant height, yield/plant, no. of seeds/pod, grain Fe concentration and grain Zn concentration. ANOVA revealed adequate variability for the studied traits. The important donors identified include EC 267591 and EC267634 for earliness, EC 78396, EC 78503 and EC 223210 (for no. of pods/plant). EC 78541-A exhibited 100 seed weight above 5 gms. EC 78393, EC 223207, EC 223150, EC 139824-A, EC 223219, EC 223211, EC 78391, EC 78513, EC 78459, EC 78510, EC 78515 exhibited 100 seed weight above 4 gm. Donors were identified for grain Fe and Zn concentration. Highest grain Fe concentration was recorded for EC 299587 (107.43 mg/kg)and maximum Zn was recorded for EC 78421 (75.92 mg/kg). The studied genotypes were grouped in 4 clusters. Indian varieties and Precoz were grouped in separate cluster (Cluster 4). Among the studied exotic genotypes, the maximum mean for grain iron concentration was recorded in obtained in EC 267636 (108.15 mg / kg) while maximum grain Zn concentration was recorded for EC 78441-B (83.21mg / kg). The population structure and diversity analysis was done for 158 genotypes using 40 SSR markers. The high PIC value (above 0.3) of studied SSR markers indicated their suitability for diversity studies. Neighbour joining (weighted average) based tree classified lentil genotypes into four clusters. Here also five Indian released varieties (DPL 62, L 4594, L 4147, L 830 and L 4076) and Precoz were grouped in separate group. The population structure analysis revealed six subpopulations (highest peak value at k = 6). The study confirms narrow genetic base of released varieties. Mediterranean germplasm lines can be utilized for broadening the genetic base of Indian cultivars.