关键词: 红椿, 红椿, 半同胞家系, 光合特性

Abstract: The maize-late rice rotation is a recently developed cropping system in the middle reaches of Yangtze river. It is important to study the seasonal dynamics of soil nutrient after fertilization in maize season and their effect on late rice growth for optimization of fertilization strategy in maize-rice system. This paper studied the no-till system of maize-rice rotation with three fertilization treatments, including no fertilizer application in the two crop seasons (MR0), conventional fertilization in maize season and no fertilization in rice season (MR1), conventional fertilization in both crop seasons (MR2). In comparison with MR0 treatment, soil available nitrogen in MR1 and MR2 plots was significantly decreased, while the soil available phosphorus content was significantly increased, and the content of available potassium in the soil was not significantly changed at the harvest of maize. The annual apparent balance of soil N and K in maize-rice system showed in the status of deficiency. However, the soil P was in the apparent surplus under MR2 treatment, the apparent equilibrium under MR1, and the obvious deficit in MR0 plots. Possibly due to deficiency in soil available nitrogen and potassium, dry matter accumulation and yield of rice under MR1 treatment were not significantly higher than those under MR0 treatment, while significantly lower than those of MR2 treatment. Accordingly, the nitrogen and potassium fertilizer should be applied in each crop season, while, more phosphorus fertilizer could be considered to apply in maize season, and less or no P fertilizer was applied in the rice season.