Suitable Rice Variety and Fertilizer for Beneficial Return in Rainfed Lowland Coarse Texture Soils at Phitsanulok

Abstract

Comparison of beneficial return between KDML105 and high yielding rice variety grown in coarse texture of unfertiled lowland rice soils under rainfed condition. The experiments were conducted in two phases : the first one was to compare the beneficial return KDML 105 and RD 23 rice at different rates of fertilizer applications, in both transplanting and pregermined direct-seeded rice at Phitsanulok Rice Research Centre. The second phase was the study beneficial return of two rice varieties namely KDML 105 and the high yielding varieties : Phathumthani 1, Phitsanulok 2, Chainat 1 with fertilizer at the rates of 6- 3 -1.5 and 12 – 6 -3 kg N- P2 O 5 – K2 O/rai in farmers fields at Phitsanulok Rice Research Centre. KDML 105 gave higher yield than RD 23 from the lower rates of fertilizer applications at 0 – 4 kgN/rai in transplanted rice. Increasing of fertilizer, the yield gaps were narrow. In pre-germinated direct – seeded rice, application of high fertilizer rates at 12 - 16 kg N/ rai, RD 23 gave higher yield than KDML 105. However, the beneficial return KDML 105 obtained was higher than RD 23 in both planting methods. In shallow water relief, KDML 105 tended to give higher yield than another; but in the flat areas, the reverse results were found. In case of the beneficial returns, KDML 105 was found to be more suitable variety than the others.