NITRATE REDUCTASE ACTIVITY AND NITROGEN CONTENT IN RELATION TO SEED SOURCE VARIATION IN <em>DALBERGIA</em> <em>SISSOO</em> SEEDLINGS
Keywords:Nitrate reductase, nitrogen, seedlings, seed source, variation, Dalbergia sissoo
ln vivo nitrate reductase activity and total reduced nitrogen content were estimated in different plant parts, i.e. leaf, stem, root and nodule, Dalbergia sissoo seedlings. These seedlings were raised from six different seed sources, viz. Sibsagar (Assam) , Chiriyapur (Uttaranchal) , Tulsipur-Gonda (UP-East) , Hissar (Haryana) , Simblewala (Jammu and Kashmir) and Kankai (Nepal) , from across a distributional range in India and Nepal and assessed at the Forest Research Institute, Dehra Dun, India. The Gonda seed source showed the highest nitrate reductase activity and nitrogen content followed by seed sources from Nepal, Chiriyapur, Jammu, Hissar and Assam. Assam seed source was observed to be the poorest in nitrate reductase activity as well as total nitrogen content. Among different plant parts, maximum nitrate reductase and nitrogen contents were recorcted in root nodules followed by leaves, roots and stems. The maximuiti variation among seed sources was recorded during the rainy season in September. The statistical analysis of various characteristics of the six D. sissoo seed sources provides a base for the selection of provenances using more evenly distributed samples from the whole range of the species.