EFFECT OF DIFFERENT LEVELS OF NITROGEN FERTILIZER AND TIMES OF APPLICATION ON GROWTH AND YIELD OF PEANUT (Arachis hypogaea L.)

Abstract

A field experiment was carried out at the experimental farm of the College of Agriculture , University of Baghdad during the 2005 summer season in loam soil. The objective of this study was to investigate the effect of different levels of nitrogen fertilizer and time of application of timings on some growth characteristics yield and quality of peanut (Arachis hypogaea L.) RCBD Asplit plot design in arrangement with four replication was used Time of application (at the beginning of vegetative growth 23/5/2005 , at the beginning of flowering 18/6/2005 and at Full flowering 11/7/2005) were assined in the main plot , while nitrogen levels (0 , 100 , 200 and 300 kg N.ha-1) were assined in the sub – plot . The results could be showed the following.the level 100 Kg N.ha-1 level gave the highest values of plant height (30.5 cm) , No :of branches (11.3) and total dry weight (94.6 gm) compared with (24.4 , 10.1 and 63.8) of zero level of N (control treatment) , respectively . The same level of nitrogen also gave the highest values of yield components. No. of pods plant-1 (49.2) , No. of seed plant-1 (65.1) and weight of 100 seeds (70.9 gm) compared with control . These highest values reflected into higher pods and seeds yield (3727 and 2168 kg.ha-1) with increase percentage (38.19 and 69.11%) respectively , compared with the control treatment .The applied levels 200 and 300 Kg N.ha-1 were gave higest plant height and total vegetative dry weight (34.8 , 36.0 cm , 110.4 and 114.5 g) , respectively compared with 100 kg N. ha-1 level . Timing of application at the beginning of flowering gave the highest values of plant height (32.4 cm) , total dry weight per plant (104.3 g) , No. of pods (46.4) , No. of seeds per plant (63.5) and 100 seed weight (66.6 gm) , respectively , these higher values were reflected into a higher pods and seeds yield (3624 and 2003 kg. ha-1) withe increasement percentage(19.48 and 24.79%) compared with the application at the beginning of vegetative growth . The interaction of nitrogen levels and timings of Application influenced significantly in seed and pod yield. the nitrogen level 100 Kg N.ha-1 at the beginning of flowering gave pod yield (4230 Kg.ha-1) and seeds yield (2513 Kg.ha-1) respectively with the increasement percentage about (60.34 and 94.50 %) as compared with control treatment.