Study the effect of nanoparticles for growth in in-vitro regeneration and molecular characterization under drought stress conditions in Banana Plants (Musa spp.)

Abstract

Banana plants are susceptible to a wide range of abiotic stresses. Drought stress is one of the most prevalent abiotic stresses that threaten the plant growth and development processes plants have shown several responses against drought conditions. These responses include changes in cellular metabolism which leads to retarded growth and development of plants. A significant reduction was observed in morpho-physio and biochemical traits within drought conditions such as plant height, the number of leaves, leaf area, chlorophyll content, relative water content, membrane stability index, catalase activity, peroxidase activity, and nitrate reductase activity. In the present study Karibale monthan, Alpan, Musa balbisiana, Poovan, Elakkie, and Matti genotypes of banana were found drought tolerant based on the cluster analysis of the pooled data, these genotypes performed better under water deficit conditions. In in-vitro micropropagation of bananas, different sterilants were tested to optimize the best combination of sterilants to get healthy growth within two banana genotypes Grand Naine and Karibale monthan. The effect of various auxins and cytokinins was assessed on two genotypes. Different combinations of plant growth regulators were formulated for shoot regeneration and rooting purpose. 21 combinations were used for shoot regeneration from which optimum results were achieved with 5mg/L BAP+1mg/l IAA and highest rooting were observed in MS media fortified with 0.5 mg/l IAA + 1.5mg/l IBA alone in Grand Naine and Karibale monthan genotype showed highest root frequency on half-strength MS media supplemented with 1.5mg/l IBA. Further, we investigated the effect of PEG concentration on growth and development parameters in invitro and ex-vitro conditions and further assessed their cumulative effect with the application of ZnO and SiO2 nanoparticles at different concentrations. i.e., 100ppm, 200ppm, 300ppm and 400ppm. Results revealed that nanoparticles have the potential to mitigate the deleterious effect of PEG within banana plants at optimum concentration. In this study, molecular characterization of 10 banana genotypes was carried out by using SSR and RAPD markers. 10 SSR and 10RAPD primers were used to distinguish genetic variation among selected genotypes. Out of 10 primers, two (SSR1 and SSR 10.1) showed 100 percent polymorphism and in the case of RAPD primers, OPL-14 and OPD-8 were highly informative as they recorded maximum PIC. The primers revealed a high degree of variation among the ten genotypes of bananas.