Screening of efficient drought tolerant accessions of Terminalia arjuna plant for sustainable Tasar sericulture production based on biochemical tools

Abstract

Aim: Tasar silkworm, Antheraea mylitta, feeds on the foliage of many plant species belonging to different families, but it prefers the foliage of Terminalia arjuna, T. tomentosa and Shorea robusta. The aim of the present study was to screen the drought-tolerant accessions of Arjuna for the successful and sustainable rearing of the Tasar silkworm. Methodology: An investigation was undertaken at the Central Tasar Research and Training Institute, Ranchi during 2016–17 and 2017–18 to study the "screening of fast-growing drought tolerant accessions of Arjuna for raising block plantations" by using biochemical tools. Ten accessions (40 saplings from each accession) were selected and allowed to grow for one year. Then, drought treatments were imposed. The experiment was laid out in a factorial completely randomised design (FCRD) with two factors. Two factors were accessions and moisture levels, i.e., control and stress. Results: The experimental result revealed that the T. arjuna accessions differed significantly for total chlorophyll contents under drought stress. Accn. 523, 525 and 135 significantly recorded higher chlorophyll content under drought-stress conditions. Water stress increased the proline concentrations in all accessions of T. arjuna, reaching 3–16 fold over the non-stressed control. Proline level was significantly increased in Accn. 525 followed by 523 and 135 at 7 and 14 days after treatment was imposed. Interpretation: Accessions of T. arjuna plant 525, 523, 123 and 135 can be used as the most drought tolerant accessions under drought conditions with limited leaf yield and quality loss. Key words: Biochemical tools, Chlorophyll, Drought, Proline, Tasar silk, Terminalia arjuna