Influence of weather parameters on the long-term yield and CO2 sequestration of high yielding lowland rice

A five-year experiment starting in 2011 was conducted to evaluate the effect of weather parameters on the yield of PSB Rc32, a modern high-yielding lowland rice variety. The contribution of rice production in reducing atmospheric CO2 concentration was also determined by calculating the amount of CO2 sequestered. Grain yield showed a continuous increase, except in 2015. Results of multiple regression analysis to predict grain yield based on solar radiation, mean temperature and total rainfall showed that the model significantly fits the data with p F = 0.0346 in dry season. Furthermore, each variable used were also significant with p = 0.039 (solar radiation), p = 0.032 (mean temperature), and p = 0.023 (rainfall). This implies that for every unit increase in solar radiation and rainfall, there is a decrease in grain yield of 1.3502 and 0.0253 tons/ha, respectively holding other factors constant. On the other hand, for every one unit increase in mean temperature the corresponding yield increases is 3.4 tons/ha. In contrast, the model from multiple linear regression was not significant using the same variables in the wet season. Biomass varies across seasons and years, but was generally higher during the wet season except in 2011 and 2013, when biomass was higher during the dry season. CO2 sequestration during the dry season ranges from 13.71 +- 1.86 to 20.38 +- 3.09 while 12.09 +- 4.07 to 18.33 +- 4.57 Mg/ha during the wet season. The trend in CO2 sequestration follows that of biomass production since biomass is the basis for calculating the amount of CO2 sequestered. In the absence of actual C content of the plant tissues. CO2 sequestration was calculated using coefficients from previously published research. Greater biomass production is desirable since this increases the amount of CO2 sequestration. To determine the actual CO2 sequestration in the experimental farm, plant tissue should be analyzed for C content.