Effect of Different Levels of Inorganic Fertilizer on Filled Grain Percentage of 50 Sri Lankan Traditional Rice Cultivars

Aims: To study the different levels of inorganic fertilizer on filled grain percentage of fifty Sri Lankan traditional rice cultivars.
Study Design: RCBD with four replicates. Twenty plants of each replicate were evaluated.
Place and Duration of Study: A field experiment was carried out during 2011/2012 Maha season and 2012 Yala season at Faculty of Agriculture, University of Ruhuna, Mapalana, Kamburupitiya, Sri Lanka
Methodology: Four levels of inorganic fertilizers were used: No fertilizer, half of the recommended dose, recommended dose and twice the recommended dose. Ten day old seedlings were transplanted in rows with 15 cm X 20 cm spacing according to the randomized complete block design. Data were collected from 80 plants of the middle row. Filled grain percentage/panicle and total biomass (g/plant) were measured after harvesting. ANOVA was performed to see the significant effect of fertilizer on filled grain percentage.
Results: The highest filled grain percentage (89.94%) was observed at twice the recommended dose in cultivar Palasithari 601 while the lowest filled grain percentage was 13.737% in rice cultivar Murunga wee at x ½ recommended dose. Hondarawala recorded the highest filled grain percentage at no fertilizer condition (86.3%). Under half recommended dose Kotathavalu, Herath Banda, Kottakaram, Karayal, Kirinaran recorded the highest filled grain percentages. Dewaredderi performed well under the recommended dose of fertilizer
Conclusion: Traditional rice cultivars respond differently to fertilizer in grain filling.