Abstract:
Two field experiments were conducted in Maha season, 2020 at Batalagoda (BG) and Maha
illuppallama (MI)) to evaluate the effects of several Eco-Friendly Fertilizer Technologies (EFTs)
on growth, yield, and plant health of rice variety Bg 352. These EFTs were developed using site specific fertilizer recommendations, biofertilizers containing locally isolated phosphate
solubilizing bacteria and cyanobacteria and biochar-urea based slow-release fertilizers (SRF),
individually or in combination to minimize the present usage of synthetic fertilizers. Number of
tillers/hill and panicles/hill, plant height at maturity, root volume and root dry weight after
harvesting, incidence of brown spot disease and leaf eating and leaf rolling pest damage in
different EFTs were compared with the fertilizer recommendation by the Department of
Agriculture (T2) which is completely based on synthetic Nitrogen (N), Phosphorous (P) and
Potassium (K) fertilizers and, a control treatment (T1), which contained no N and P. All the tested
growth and yield parameters significantly differed (P<0.05) between the two locations and among
treatments. Compared to the plants grown without N and P (T1), tillers/hill, panicles/hill, plant
height, root volume and root dry weight were significantly higher (P<0.05) in the rest of the
treatments at both locations, with the exception of the number of tillers/hill and root dry weight
in MI-grown plants. In BG-grown plants, tillers and panicles/hill showed no significant difference
between T2 and T3 treatments (i.e., 100% N in the form of urea as a site-specific
recommendation). T4 and T5 treatments at MI have resulted in significantly higher number of
tillers and panicles/hill and root volume and dry weight. T4 and T5 treatments contained 65% of
site-specific N recommendation in the form of SRF. T1 reported the highest brown leaf spot
incidence at both locations. No significant difference was reported in the incidences of leaf rolling
and leaf eating pest damage between the locations and among treatments. Results revealed the
possibility of implementing EFTs, especially T3, T4 and T5 in a location specific manner without
compromising the tested growth and yield parameters and susceptibility to studied pest and
diseases and most importantly by reducing the present usage of urea by about 30%.
