Response of Some Rice cultivars to Plant Spacing and Nitrogenous Biofertilization

Abstract

Two field experiments were carried out at the experimental farm, Rice Researchand Training Center, Agricultural Research Center, Egypt, during the two growing seasons, 2010and 2011. The experiments were conducted to investigate the effect of different nitrogenbiofertilizers and plant spaces on some growth characters, yield and its attributes and grain qualitycharacters of some Egyptian rice varieties. A split split-plot design with three replications was used.The main plots were devoted to the rice cultivars namely Giza 178, Sakha 103 and Sakha 105,while the combination of five nitrogen fertilizer sources was arranged in the sub plots (i.e. control,nitrogen recommended rate of, micorrhiza +50% N rate, blue green + 50% N rate and microrrhiza+blue green + 50% N rate) were assigned to the sub plots and three plant spacings (i.e. 10x150,10x20 and 10x25) were assigned to sub sub plots.The obtained results could be summarized as follow:Sakha 105 cultivar recorded the highest panicle weight, No. of filled grains/panicle, 1000-grainweight, and grain yield followed by Giza 178 while, Sakha 103 recorded the lowest values. On theother hand, Giza 178 rice cultivar gave the largest No. of panicles/m2 in both seasons and the bestharvest index (HI). Rice cultivar Sakha 103 gave the highest straw yield followed by Sakha 105.Rice cultivar Sakha 103 gave the highest hulling % while, Giza 178 recorded the lowest value inboth seasons. But Sakha 105 cultivar surpassed significantly the other two cultivars in head riceand milled rice %.Plant received half of the recommended rate of mineral nitrogen combined with micorrhiza+ blue green recorded the greatest panicle grain weight, no. of filled grain/panicle, no. ofpanicles/m2, weight of 1000-grain, grain yield and harvest index. The application of recommendedrate of nitrogen out yielded the other nitrogen sources and control in rice straw.Highly significant differences were recorded between the three different plant spacing. Rice plantswhich planted at 10 x 20 cm gave the highest values in panicle weight, no. of filled grains/panicle,No. of panicles/m2, weight of 1000-grain, grain yield . While, the narrow plant spacing 10 x 15 cmgave the highest value for straw yield among the other plant spaces. The greatest HI was recordedwhen rice cultivars were planted at 10 x 20 cm while no differences was found between the othertwo plant spacing.Analysis of variance indicated that the differences in hulling % among the plant spacingwere significant. The highest means of hulling, milling and head rice % comes from planting at 10 x20 cm followed by 10 x 25 cm.The highest values on most traits, except straw yield, were obtained from the combinationof Micorhiza + Blue green + 50% of recommended nitrogen rate /ha under the medium spacingconditions with Sakha 105 rice cultivar.