Growth and yield of three high-yielding varieties of lowland rice as affected by application of inorganic fertilizers Darwis Suleman(*a), Hamirul Hadini(b), Didik Raharjo(c), Syamsu Alam(a), Dewi Nurhayati Yusuf(a)
a) Department of Soil Science, Halu Oleo University, Kendari 93232
b) Department of Agrotechnology, Halu Oleo University, Kendari 93232
c) Assessment Institute of Agricultural Technology, Kendari 93114
*Email: darwis_suleman[at]yahoo.com
Abstract
Currently, the need for rice in Indonesia increases linearly along with the soaring of population. However, the rice production tends to be levelling-off. This study evaluated 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 in 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). Our result suggest the importance of cropping system pattern to prevent the soaring of harmful attacks of pest and disease and the evaluation of fertilizer recommendation that had been used a dozen consecutive years.
