0023-6152

AA00697606

24443

査読無

0023-6152

AA00697606

A field research was conducted at the research farm of Wheat Research Centre, Dinajpur, Bangladesh for the two consecutive years of 1999-2000 and 2000-2001 to find out the appropriate management of nitrogen fertilizer in surface seeded wheat and to identify the wheat genotype preferable to surface seeding in rice-wheat alternative cropping system. The experiment was executed in split-plot design assigning three wheat genotypes namely Kanchan, Protiva and Gourab in main plots and Seven different management of nitrogen fertilizer in subplots. Nitrogen content in grain and straw of wheat was determined; root growth was studied at post anthesis stage of the crop. Both the genotype and N management have created a significant impact on the root length density (RLD), N uptake, N use efficiency and grain yield of surface seeded wheat. Three equal split application of N fertilizer as basal during seeding, top dress at crown root initiation stage （20 days after sowing） and at first node stage （35 days after sowing) was found best that produced significantly higher grain yield by increasing spikes m^<-2> and number of grains spike^<-1>. RLD at the active root zone （0-15 cm）, N uptake and nitrogen use efficiency （NUE） of wheat was the highest under the same N management. Among the wheat, genotypes Kanchan produced higher grain yield that was attributed from higher number of spikes m^<-2> and number of grains spike^<-1>. Agronomic NUE, Grain N, total N uptake and RLD of Kanchan was higher compare to other genotypes.