Response of Nutrition on Growth and Flowering of Dendrobium Orchids under Eastern Himalayan Region

A study on response of nutrition on growth and flowering of Dendrobium orchids under low cost poly house at Instructional farm, Department of Floriculture, College of Horticulture & Forestry, Pasighat, Arunachal Pradesh was conducted during April 2011 to March 2012. Three levels of nutrient mixtures (NPK 19:19:19) viz. 2g/l, 4g/l and 8g/l with commercial micronutrient mixture at 0.2 per cent and four varieties namely, TSG, Sonia, Thongchai Gold and Singapore White were selected for their evaluation. Significant response of nutrition, varieties and their interaction was observed. Cultivar Singapore White showed maximum plant height (65.09cm), number of leaves per cane (10.40), leaf length (19.75cm), cane girth (16.68mm) and minimum internodal space (4.82cm), while, highest number of canes per clump (6.93) and leaf width (6.19cm) was observed with cultivars Sonia and TSG, respectively. Earliness in flowering (93.45 days), increased flower diameter (8.12cm), number of florets per spike (13.57), number of spikes per plant per year (3.24) and fresh weight of spikes (34.07g) was associated with cultivar Sonia. However, cultivar TSG showed increased spike length (45.65cm) and rachis length (30.81cm). Higher dose of nutrition (8g/l) enhanced growth and flowering characters of all varieties as compared to lower dose. In interaction, significant response was noticed with higher dose of nutrition in cultivar Sonia, TSG and Singapore White, respectively.