EFFECT OF NITROGEN SOURCES AND SPACING ON THE GROWTH AND YIELD OF T-AMAN RICE CV. BRRI dhan 31

A Thesis Submitted to the Department of Horticulture Sher-e-Bangla Agricultural University, Dhaka in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE (MS) IN AGRONOMY

The experiment was conducted at the Agronomy Field, Sher-e-l3angla Agricultural University. Ohaka from June to November 2007 to evaluate the effect of nitrogen sources and spacing on the growth and yield of T-a,nan rice of BRRJ dhan 31. The experiment comprised of three nitrogen sources viz. prilled urea (PU). Urea super granules (USC) and foliar application of area, and five spacing viz. 15 cm 20cm x 15 cm, 25cm x lS cm, 3Ocm x l5cm and 35 cmx IS em.Theexperiment was laid out in a split plot design with three replications assigning nitrogen sources in the main plot and spacing in the sub-plots. Nitrogen sources significantly changed all growth characters and yield attributes except I 000-grain weight. The highest plant height (105.70cm at harvest), number of tillers hill" (11.03 at 60 DAT), di7' weight plant' (101.95 g at harvest) were obtained from IJSG. The maximum grain yield (4.58 ha") was obtained from USC. which was attributed of higher number of effective tillers hillt (7.55), the highest number of filled grains panicle" (92.60) and highest panicle length (26.19 cm). The minimum grain yield (3.53 t ha") was obtained from foliar application of urea. The effect of spacing was significant for all the crop characters except 1000-grain weight. Plant height, number of tillers hill 1 , dry weight plant", effective tillers hill'. straw yield and biological yield were higher with widest spacing (35 cm x 15 cm). But number of filled grains panicle" (102.2), panicle length (27.17cm), grain yield (4.76 t ha") and harvest index (45.97%) were maximum in 25 cm x IS cm spacing. The interaction between nitrogen sources and plant spacing had significant effect of crop characters except 1000-grain weight. Plant height, number of tillers hill" and dry weight showed higher with the interaction of uSC and 35cm cm spacing. Number of effcctive tillers hill" . number of filled grains panicle", panicle length, grain yield, biological yield and harvest index were found highest with the combination effect of USC and 25 cm x IS cm spacing. On the other hand, lowest grain yield and straw yield was obtained from the interactions effect of foliar urea with 35cm x 15 cm spacing and USC with 15 cm x 15 cm spacing, respectively.