A comparative analysis of morphological and cellular impacts on polyploids and diploids in Lathyrus

Abstract

Lathyrus is the third most important cool season pulse crop of India, occupying an area 0.58 million ha with an annual production of 0.43 million tonnes. Enhancing vegetative growth might be a viable strategy for boosting fodder production. The goal of this experiment is to induce auto-polyploidy and then evaluate the polyploids to see how they compare to their diploid counterparts. The present experiment deals with inducing auto-polyploidy along with evaluation of obtained polyploids to check the polyploidy effect over the diploid counterparts. Induction of polyploidy was conducted in Grass pea (Lathyrus sativus L.) genotype, Ratan and Pusa 24; seed treatment method was conducted in Ratan using 3 different colchicine concentrations (control, 0.02%, 0.04% and 0.05%) and seedling treatment was conducted in Pusa-24 (3 days old and 7 days old seedlings) using 2 different colchicines concentrations (control, 0.20% and 0.50%). The effect of polyploidy was checked over their diploid counterparts. Polyploidy was determined using observations of stomata, nucleus size and morphological characteristics. Higher mortality rate was found in seedling treatment treatment than seed treatment. In all three Ratan treatments, polyploids were found in the populations. There were substantial changes in morpho-physiological parameters when Ratan genotype and colchicine treatments were combined. The same can be shown in a karyotypic analysis. Seed treatment method showed better result than seedling treatment, also out of three (0.02%, 0.04% and 0.05%) concentrations 0.04% showed the best result. Total 6 plants were confirmed through microscopy methods. The form of the leaflets, the size of the leaf area, and the number of leaves were all more variable. In both floral and seed dimensions, there are more variances. There were negative significant differences in seed number and stomatal number. Positive significant difference were observed in leaf dimensions including length (cm), width (cm) and leaf area (m2), size of the nucleus (μm2), stomatal length and width, flower length (cm) and width (cm), days to first flowering, no. of flowers plant-1, no. of seeds plant-1, seed length (mm), seed width (mm) and 10 seed wt.(g). Induction of polyploidy led in higher, more branched plant/ plant, with a 10 seed weight increase. This approach may be utilised in plant breeding projects to improve fodder production efficiency and in the selection of higher adaptable genotype.