RESPONSE OF VERMICOMPOST AND BIOCHAR ON YIELD AND QUALITY OF FRAGRANT RICE THROUGH MINIMIZATION OF NITROGEN

Abstract

The pot experiment was conducted at the experimental field of Sher-e-Bangla Agricultural University, Sher-e-Bangla Nagar, Dhaka during the period from July to December 2019 to assess the response of vermicompost and biochar on yield and quality of fragrant rice through minimization of nitrogen. Fragrant rice cultivars BRRI dhan80 was used as planting material. The experiment consisted of three factors: Factor A: Three levels of vermicompost as- Vm 1 ii

: 2.5 t ha -1 , Vm 2 : 5 t ha -1 , Vm 3 ; Factor B: Three levels of biochar as- Bc 1 : 2.5 t ha -1 , Bc 2 : 5 t ha -1 , Bc 3 ; and Factor C: Two levels of nitrogen as- N 1 : 37 kg N ha -1 and N 2 (recommended dose). The three factors experiment was laid out in Randomized Complete Block Design with three replications. The result revealed that amendment of vermicompost, biochar and nitrogen had significant effect on most of the yield and quality contributing parameters. Plant height, tillers number, effective tillers, panicle length, filled grains, total grain yield, 1000-grain weight and protein content increased with increasing vermicompost, biochar and nitrogen. But in case of nitrogen lower level 37 kg N ha -1 showed slightly higher grain 2-AP content in fragrant rice. The highest grain yield plant -1 (65.21 g) was recorded from Vm 3 Bc 3 N 2 treatment combination and the lowest grain yield plant -1 (41.49 g) was observed from Vm 1 treatment combination. The highest protein content in grain (11.03%) was recorded from Vm 3 Bc 3 N 2 treatment combination whereas the lowest protein content in grain (7.06%) was observed from Vm 1 Bc 1 N 1 treatment combination. The highest grain 2-AP (1.53 µg g -1 ) was recorded from Vm 3 Bc 3 N 1 treatment combination and the lowest grain 2-AP (0.34 µg g -1 ) was observed from Vm 1 Bc 1 N 1 treatment combination. So it may be concluded that applications of vermicompost at 7.5 t ha -1 exhibited the best performance on most of the traits studied under present study which was at par with 5.0 t ha 1 . Application of biochar at 7.5 t ha -1 also exhibited the best performance studied under present experiment. Soil application of nitrogen with 42 kg ha -1 exhibited the best performance on most the yield and quality traits studied under present experiment except, in case of grain 2-AP content the application of nitrogen with 37 kg ha

performed the best one.