| 1. | Wm in no - tillage corn in wheat - corn double cropping system in north china 免耕制度中的杂草动态 |
| 2. | Continuous double cropping 两熟连作 |
| 3. | Losing irrigation water may mean either abandoning land or less double cropping 灌溉用水短缺的直接影响不是废弃农田,就是减少一年两作。 |
| 4. | Situation , potential and strategies of grain production in double cropping region of china 北方农牧过渡带农户农业生产系统模式评价与优化研究 |
| 5. | Experimental study on technology system of soybeans rotary tillage and seeding of double croping one year 一年两作旋播大豆技术体系的试验研究 |
| 6. | Theroy and techniques of vigorous root - strong culm - weighty panicle cultivation method for double cropping rice 双季稻旺壮重栽培法的理论与技术 |
| 7. | Jin et al . ( 1990 ) has used this systematic approach successfully in guiding maximum yield research in wheat - corn double cropping systems 金继运等人1990年用该方法成功地指导了小麦-玉米一年两熟种植制度的最高产量研究。 |
| 8. | Dissemination of rice water weevil lissorhoptrus oryzophilus kuschel to the coastal area in north of zhejiang province where the single and double cropping rice were mixed cropped 稻水象甲传入浙北沿海水稻单双季混栽区 |
| 9. | Wheat - maize rotation is one of the major double cropping systems , taking an important place in grain production in shandong province , about 2 . 36 million ha accounting for 54 . 5 % of the total cultivated acreage , producing 21 . 7 million tonnes grain , 57 . 9 % of the total in 1990 小麦-玉米轮作是主要一年两作制之一,在山东省粮食生产中起重要作用,大约236万公顷,占总耕地面积的54 . 5 % ,生产2170万吨粮食,为1990年粮食总产的57 . 9 % 。 |
| 10. | Some demonstration and extension work based on existing scientific results have been done such as developing grain in large area of land using comprehensive cultivation measures in zibo city in 1987 and research on response of highly yielding crops to potassium and proper distribution of potash fertilizers in double cropping systems supported by ppic in 1990 已根据现有科技成果作出一些示范推广工作,如1987年在淄博市用综合栽培措施在大面积土地上开发粮食生产,以及1990年在ppic资助下研究一年两作制下高产作物对钾的反应和钾肥合理分配。 |