Abstract:
Rice production in the Vavuniya district has increased over the last three decades
due to high-yielding varieties, the use of plant nutrients and irrigation. The Sri Lankan
government has supported stimulating rice production by introducing new policies on
fertilizer subsidies. On May 6, 2021, the government restricted and banned the import
of fertilizers and agrochemicals; however, the government lifted the restriction and ban
before the onset of the Maha season of 2022/2023. This study attempted to evaluate
the comparative effect of organic and inorganic applications on rice cultivation in
Vavuniya district over two consecutive Maha seasons: Maha season of 2021/2022 and
Maha season of 2022/2023. A paired t-test was used to analyze and compare the yield
of rice estimated by the crop cut survey conducted in Vavuniya district. Meanwhile,
GPS location was recorded, and locations were locked in the GIS system. The results
of paired t-test showed that there was a significant (p< 0.01) difference between yield
under the organic application during Maha season of 2021/2022 (Mean yield = 1049.4
kg, SD = 263.2) and the inorganic application during Maha season of 2022/2023 (Mean
yield = 1429 kg, SD = 298.6). This study also found that the farmers faced 4% loss to
produce 1 kg of rice during the Maha season of 2021/2022 and the farmers received 4%
to 19% profit to produce 1 kg of rice during Maha season of 2022/2023.
