Seedling age and nitrogen application affect on dry matter accumulation, partitioning and nutrient status of rice under temperate conditions

Abstract

Rice is the most important crop at the global level, as it used as a staple food in most of the countries of the world. Transplanting aged seedlings of paddy has a detrimental effect on the crop performance, which needs to be overcome for sustaining the productivity. Leaf colour chart based nitrogen application is an efficient and economical tool for enhancing the rice productivity and nitrogen use efficiency. With this in mind, a field experiment was conducted during kharif 2011, at the Research Farm of SKUAST-K, Shalimar, Srinagar (Kashmir) to optimize the seedling age of rice (Oryza sativa L.) under late transplanting conditions and to assess the suitability of using leaf colour chart as a nitrogen management tool to improve the performance of rice. The experiment was established in Randomized Block Design, with three replicates, 3 seedling ages and 6 nitrogen application treatments. The analyses of data revealed that 35 days old seedling recorded significantly higher total dry matter accumulation and dry matter partitioning to panicle (8.2 t ha-1) and leaf (2.4 t ha-1); grain yield (7.4 t ha-1); N, P and K uptake (11.6, 3.1 and 11.3 kg ha-1, respectively) (p<0.05). Among nitrogen application treatments significantly higher dry matter accumulation; yield (8.6 t ha-1) and N, P and K uptake (14.1, 3.6 and 12.7 kgha-1, respectively) was found in ½ N as basal and remaining at LCC <4 @20 kg ha-1 (p<0.05). Age of seedling and time of nitrogen application did not affect N, P, K and protein content of grain and straw significantly (p>0.05). It is concluded that the yield of rice can be improved by transplanting 35-days old seedling under late transplanted conditions in temperate regions and by following LCC guided nitrogen management.