Abstract
The effects of reflected light from the ground, using reflection sheets, on the seed yield and photosynthetic rates of middle and lower leaves of soybean canopy were investigated. The cultivar Suzukari was grown at three different planting desities in the field (i.e., 14.3(10cm plot), 9.5(15cm plot) and 5.7 (25cm plot) plants m<-2>). The light reflection treatment was carreied out from the floral bud differentiation stage to maturity by covering the field ground between rows with reflective sheets. Seed yields increased in both 15 and 25 cm plots as the result of reflection treatment. It depended on the number of pods and seeds at nodes lower than the 9th node. In the 10 cm plot, the number of pods increased at lower nodes, however, the total yield did not increase. Light intensities increased slightly between plants within a row on the cloudy day, however, it increased considerably between rows on both fine and cloudy days in both the 15 and 25 cm plots. The photosynthetic rates of middle and lower leaves on the main stem increased in all planting densities as the result of reflection treatment. During the period from flowering to the pod formation stage, CGR increased as the result of reflection treatment mainly due to the incrase in LAI. Whereas, during the period from pod formation to the seed development stage, CGR increased as the result of reflection treatment mainly due to the increase in NAR.
