Growth and yield of three high-yielding varieties of lowland rice as affected by application of inorganic fertilizers

Abstract

The need for rice in Indonesia currently increases linearly along with the soaring of population. However, the rice production tends to be levelling-off. This study evaluates the yield potential of three lowland rice varieties under different rate of fertilizer. The varieties of Mekongga, Ciherang and Inpari30 sub1 were grown under five fertilizer treatments: 90 %, 100 % served as a control, 110 %, 115 %, and 120 % of recommended rate with three replications and laid out in a factorial block design. The study was located on a silty loam and irrigated soil. ANOVA was applied and followed by a Tukey test at a 5 % level. Among three varieties, Mekongga and Inpari-30 sub1 produced more yield than Ciherang by 6.71 and 6.77 t ha−1, respectively. Increasing the rate of fertilizers caused the increase of the yield significantly. The highest grain yield was recorded by the application of 120 % of recommended rate by 7.82 t ha−1. Fertilizer rate was positively correlated with grain yield (r=0.97). The result shows the importance of cropping system pattern in order to prevent the soaring of harmful attacks of pest and disease as well as the evaluation of fertilizer recommendation that had been used a dozen consecutive years.