Morphological and Molecular Assessments of Sphenostylis stenocarpa (Hochst. Ex A. Rich.) Harms. Accessions Induced Using Sodium Azide

Abstract

Sphenostylis stenocarpa is a valuable, highly nutritious and adaptable crop. The main drawback towards its cultivation and utilization is narrowness of the germplasm available to plant breeders for its genetic improvement due to low seed yield, hard seed coat, and presence of antinutritional factors. There is limited information on its genetic improvement through mutation induction, hence the study was conducted to evaluate molecular characteristics as well as vegetative and yield performances of two accessions of S. stenocarpa in response to treatments. Seeds of two accessions (TSs 10 and TSs 86) of S. stenocarpa were sterilized, and induced with (0, 0.01, 0.03, 0.05, 0.07, 0.1, and 0.2%) concentrations of sodium azide. Treated seeds were washed, planted in Petri dishes and subsequently transferred to appropriately labeled pots. Increases in plant heights, number of leaves and number of branches were observed in both accessions while reductions were observed in plant heights, days to peduncle initiation as well as days to first and 50% flowering. Reduction observed in days to first and 50% flowering and days to peduncle initiation can lead to early maturing varieties. Twelve randomly selected primers were tested and 7 polymorphic ones were used. The number of amplicons varied from 7 to 19. The highest PIC was observed in primer OPT-07 (92%). Hence, these markers can be explored in S. stenocarpa breeding programs. Sodium azide at 0.07% induced increase in vegetative characters such as plant height, number of leaves as well as number of branches/plant in TSs 10 while in TSs 86 dosage of 0.01% induced reductions in reproductive characters such as peduncle length as well as days to first and 50% flowering. These concentrations can be used in future for inducing variability in these accessions. The test crop can further be genetically improved for utilization and conservation in future.