J. Sci. Technol. (Dinajpur) Vol. 8: 142-149 (2010) ISSN 1994-0386 INFLUENCE OF NITROGEN FERTILIZATION AND IRRIGATION ON TI{E GROWTH AND SEED YIELD OF LENTIL M.A. Salaml, M.S.Islam2, M.K.Islam3,M.A. Kawochara and M.S.I. Sikdars ABSTRACT An experiment was conducted at the Sher-e-Bangla Agricultural University farm, Dhaka to study the influence of nitrogen fertilization and irrigation on the growth parameters of lentil (Lens culinaris) cv. BARI mashur-4 during the period from November 2006 to March 2007. Ten treafinent combinations of 20, 30, and 40 kg N ha-1 applied at sowing and 2 equal split at sowing and flowering stage with and without irrigation were tested. Irrespective of treatment differences the tentil plant as a pulse crop showed a lag phase in early growth stage (up to 25 DAS) to produce number of leaves, leaf dry weight and stem dry weight per plant. Application of 20 kg N har as basal with 20 kg N ha-r as split application with one irrigation at flower initiation stage (55 DAS) of lentil improved the growth parameters significantly. Maximum dry matter eventually supported the plant to produce more number of branches and biological seed yield. Key words: Growth, lentil, irrigation, nitrogen INTRODUCTION Lentil (Lens cufin)rls) is one of the important pulse crops grown in Bangiadesh. Among the pulse crops, lentil ranks second in acreage and production but ranks first in market price. Lentil grain contains 59.8Vo carbohydrates, 25.8Vo protein, 107o moisture, 4Vo mineral and 3Vo vitamins (Khan, 1981; Kaul, 1982). The green plants can also be used as animal feed and its residues have manural value. Lentil grains contain high protein, good flavor and easily digestible component. It may play an important role to supplement protein in the cereal-based low-protein diet of the people of Bangladesh but the acreage and production of lentil are steadily declining (BBS, 2006). The average yield of lentil is 0.80 t ha-l which is very poor in comparison to lentil growing countries of the world (BBS,2006). There are many reasons of lower yield of lentil. The management of fertilizer is the important one that greatly affects the growth and development of this crop. Pulses although fix atmospheric N, there is evident that application of N fertilizers becomes helpful in increasing growth and yield (Patel et al., 1984 and Ardeshafla et al., 1993). N is essential for pulse crops because it is the component of protein (BARC, 1997). Lentil is a rain fed crop in most countries, grown either during the wet season or on the residual soil moisture in the post-rainy season. Hence, in most circumstances irrigation is not applied but most varieties respond favorably to added water resulting in higher yields, especially when irrigation is given at the time of water stresses or during short drought periods (Lawn, 1978, Miah and Carangal, 1981). Irrigation during flowering stage helps: for retention of flowers and pod development. Hence, the present study was carried out to determine the optimum N dose and appropriate time of N application'along with inigation for maximizing the seed yield of lentil. lResearch and Development Fxecutive, Green Bangla Agrovet Ltd.; 2Product Development Officer, Rajib Agro Chemicals Limited, Dhaka; 'Senior Scientific Officer, Department of Agronomy and 4Scientific Officer, Plant Genetic Resources Center, Bangladesh Agricultural Research Instit ;e; sDepartment of Agronomy, Hajee Mohammad Danesh Science and Technology University, Dinajpur- 5200, Bangladesh. 142