The field experiment was located in Dengjiapu State Rice
Cropping Farm, Yujiang County, Jiangxi province in southeast
China (N28
15
0
,E116
55
0
). The research site is representative of a
typical subtropical moist climate with an annual mean temperature of about 17.6
C; a minimum monthly mean temperature of
5.9
C in January and a maximum monthly mean temperature of
30.0
C in July; an average of 269 frost-free days and a rainfall of
1727 mm, about 50% of which falls from March to July. The studied
soil was a loamy Fluvisol derived from river alluvial deposits,