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it de- pends on the type of mulch and color of the plastic ?lm. Plastic ?lm mulching is more effective for reducing soil-water con- sumption/loss compared to straw mulching. While black plastic mulch increases soil temperature (Ibarra et al., 2012), silver color plastic mulch reduces it (Lamont, 1993). The color of the plastic mulch affects microclimate around the crop by modifying radia- tion budget (absorptivity vs. re?ectivity) of the surface (Filipovi? et al., 2016) that can reduce soil-water consumption (Deng, Shan, Zhang, &

Turner, 2006) and increase water use ef?ciency (Kumar &

Dey, 2011). However, use of plastic ?lms for mulching is often limited due to their high cost as well as high cost of their collection and recycling of their residues (Qin, Wang, Guo, Yang, &

Oenema, 2015). Selection of appropriate mulching materials for green soy- bean production under rain-fed conditions in hot summer, like at central Japan, is very important. This study investigated the effects of organic and inorganic materials on soil hydrothermal regimes, which in?uence growth, yield and water-use ef?ciency of green soybean under rain-fed condition in central Japan. 2. Materials and methods 2.1. Description of study site and treatments The ?eld experiment was conducted at Gifu University farm in Japan (35° 27'

N and 136° 44'

E,

12 m above sea level) by culti- vating soybean (Glycine max) during

20 May to

27 August 2015. The long-term (2000C2014) temperature and precipitation data of the site, collected from a nearby weather station (Gifu WMO sta- tion ID: 47632), are illustrated in Fig. 1. The mean air temperature during the soybean growing season increased from 22.0 °........