In order to research effects of the nitrogen top-dressing levels on carbon-nitrogen metabolism and yield of Desmodium styracifolium, a field experiment was conducted on the research farm of Guangxi University in 2007....In order to research effects of the nitrogen top-dressing levels on carbon-nitrogen metabolism and yield of Desmodium styracifolium, a field experiment was conducted on the research farm of Guangxi University in 2007. Some physiological indexes and yield ofD. styracifolium were compared among five nitrogen top-dressing levels （0, 37.5, 75.0, 112.5 and 150.0 kg N. hm-2）. Results showed that the nitrogen top-dressing could significantly increase the contents of chlorophyll, soluble protein, sucrose and nitrogen as well as nitrate reducase activity. However, there were no significant differences in most of these indexes under high nitrogen levels. Consistently, there was no significant difference in yield among nitrogen top-dressing levels of 75 kg N.hm-2, 112.5 kg N. hm-2 and 150 kg N-hm-2. Therefore, the optimum nitrogen top-dressing level ofD. styracifolium was 75 kg N. hm-2.展开更多
The effect of different formula of NPK and twice topdressings on rice growth in typical double cropping rice area, which located at Kaihui, Ganshan, Matang and Xinqiang towns, were studied on field experiment in order...The effect of different formula of NPK and twice topdressings on rice growth in typical double cropping rice area, which located at Kaihui, Ganshan, Matang and Xinqiang towns, were studied on field experiment in order to select the formula of compound fertilizer and top dressing mode for double cropping of rice production in Hunan. The results showed that the optimized formulated fertilizer treatment, which increased the proportion of phosphorus and potassium and reduced its nitrogen fertilizer by 7.5 kg/hm2 can ensure early rice stable. Fpr example, the yield of late rice increased by 187.5-378.0 kg/hm2 compared with the conventional complex fertilizer （N-PO5-K2O formula of 20-10-10 for early rice and 26-10-13 for late rice）. The N-P2O5-K2O formula 18-14-16 of optimized formulated fertilizer which was suitable for early rice production, and the other N-P2O5-K2O formula 18- 9-16 was suitable for late rice production. The rice yields for top-dressing at tiller- ing stage and booting stage can increased by 187.5-382.5 and 258.0-415.5 kg/hm2 for eady and late rice and the nitrogen use efficiency advanced 10.9-24.2 percent- age points （31.5%-51.1%） for eady rice and 8.3-13.4 percentage points （36.2%- 64.9%） for late dce compared with the top-dressing at tillering stage.展开更多
基金Supported by Scientifi c Research Foundation of Guangxi University (x061106)
文摘In order to research effects of the nitrogen top-dressing levels on carbon-nitrogen metabolism and yield of Desmodium styracifolium, a field experiment was conducted on the research farm of Guangxi University in 2007. Some physiological indexes and yield ofD. styracifolium were compared among five nitrogen top-dressing levels （0, 37.5, 75.0, 112.5 and 150.0 kg N. hm-2）. Results showed that the nitrogen top-dressing could significantly increase the contents of chlorophyll, soluble protein, sucrose and nitrogen as well as nitrate reducase activity. However, there were no significant differences in most of these indexes under high nitrogen levels. Consistently, there was no significant difference in yield among nitrogen top-dressing levels of 75 kg N.hm-2, 112.5 kg N. hm-2 and 150 kg N-hm-2. Therefore, the optimum nitrogen top-dressing level ofD. styracifolium was 75 kg N. hm-2.
基金Supported by the Project in the National Science&Technology Pillar Program(2011BAD11B05)the Project in the National Science&Technology Pillar Program(2012BAD15B04)~~
文摘The effect of different formula of NPK and twice topdressings on rice growth in typical double cropping rice area, which located at Kaihui, Ganshan, Matang and Xinqiang towns, were studied on field experiment in order to select the formula of compound fertilizer and top dressing mode for double cropping of rice production in Hunan. The results showed that the optimized formulated fertilizer treatment, which increased the proportion of phosphorus and potassium and reduced its nitrogen fertilizer by 7.5 kg/hm2 can ensure early rice stable. Fpr example, the yield of late rice increased by 187.5-378.0 kg/hm2 compared with the conventional complex fertilizer （N-PO5-K2O formula of 20-10-10 for early rice and 26-10-13 for late rice）. The N-P2O5-K2O formula 18-14-16 of optimized formulated fertilizer which was suitable for early rice production, and the other N-P2O5-K2O formula 18- 9-16 was suitable for late rice production. The rice yields for top-dressing at tiller- ing stage and booting stage can increased by 187.5-382.5 and 258.0-415.5 kg/hm2 for eady and late rice and the nitrogen use efficiency advanced 10.9-24.2 percent- age points （31.5%-51.1%） for eady rice and 8.3-13.4 percentage points （36.2%- 64.9%） for late dce compared with the top-dressing at tillering stage.
