Effect of Ridging Using an Up-cut Rotary Tiller on Soil Temperature and Yield of Winter-cropped Lettuce

Abstract

In this study of the cultivation of winter-cropped lettuce following paddy rice, a tendency for higher ridge surface temperature was observed when mulching was performed after ridging with an up-cut rotary tiller, compared to that with a down-cut rotary tiller. Further investigation revealed that the rate of surface soil pulverization was higher in up-cut rotary tiller ridges than down-cut ridges, leading to the observed increase in soil temperature. Furthermore, this increased temperature related to increased lettuce yield associated with use of an up-cut rotary tiller.