Abstract:
A field experiment was conducted during the Maha season from August
2019 to May 2020 at Regional Rice Research and Development Center,
Bombuwala, Sri Lanka to investigate nitrogen response of promising
rice line of Bw 12-574 compared at growth and flowering stages of
that recommended rice variety (Ld 368). Growth parameters and yield
components of both treatments were compared under five different
nitrogen levels i.e., 0, 50, 100, 150, and 200% recommended by the
Department of Agriculture. The experimental design was a Randomized
Complete Block Design with three replicates. Two varieties were tested
under 5 nitrogen levels. Data were analyzed by analysis variance (ANOVA)
and mean separation procedure by LSD using appropriate SAS procedures.
Plant height, number of productive tillers, panicle length, leaf colour intensity, and chlorophyll content of leaves in both Bw 12-574 and Ld 368
showed an increasing trend against added nitrogen. The higher nitrogen
dosages were influencing the increase of flowering days. The yield
parameters including length of panicle and number of grains per panicle
have shown significant differences (p=0.05) between the tested line and
recommended variety. However, no significant difference was observed
between the tested line and recommended variety with respect to filled
grain percentage and grain yield. Hence, the response to nitrogen of Bw
12 – 574 was found to be similar to the recommended variety, Ld 368. The
study concludes that the same nitrogen recommendation applied for Ld
368 would be recommended for promising rice line Bw 12-574. However,
further investigations are needed to confirm the findings.
