Planting Methods Affecting Soybean Yields Grown after Rice

Abstract

Soybean cultivation in dry season is mostly done in irrigated areas and was planted in the field after harvesting rice. There are various of soybean planting methods. Different methods are suitable for areas with different plot preparations. The objective of this experiment was to investigate the most suitable planting method of soybean after rice production to obtain the highest yield and value for investment. The experiments were conducted at the Chiang Mai Field Crops Research Center in the dry season during 2018 - 2020. Chiang Mai 60 variety was used in this experiment. Randomized complete block design with 4 replications was set and different planting methods were arranged as treatments; 1) recommended method (pushing planting hole method), 2) pecking wheel method, 3) sowing method, 4) recommended + rice straw mulching methods, 5) pecking wheel + rice straw mulching methods, and 6) sowing + rice straw mulching methods. The results from combined analysis of yield from 3 years revealed that different planting methods was significantly affected soybean yield and growth. It was found that recommended + rice straw mulching methods, pecking wheel + rice straw mulching methods and sowing + rice straw mulching methods gave no difference in yields (447-449 kg/rai). These three methods, however, attained a significantly higher yield than the other methods tested. The increasing of number of pods/plant was a major yield component responsible for yield increase. The worth investment (benefit cost ratio, BCR) of all treatments were 1.06-1.66. The method of sowing followed by rice straw mulching had the highest value in terms of investment.