Compared with conventional cultivation, high yielding cultivation had better economic effect. It obtained double effects on net income per 1/15 ha and labor productivity; and showed increasing by about 50% in per100-yuan investment profit and cost profitability. Regressional analysis of technical economics shows that highyielding cultivation has more technical containings, and higher output is closely related to better scientific technology. There is different effect among the technical components on high yielding cultivation.
The different collocation patterns of double-cropping rice cultivars in the rape-rice-rice system areahave demonstrated the following results: it is easy for reaching high yield to collocate the late-maturing early rice(LME), Xiangzaoxian 19 and 810 S/D100 with the late-maturing late rice (LML),Pei’ai 64S/Teqing;while the midmaturing early rice (MME) with the LML or the LME with the mid-maturing late rice (MML) gives the loweryields, and the early-maturing early rice (EME) with LML gives the lowest output. In order to produce high yield indouble-cropping rices and develop the yield potential for the early rice, it is necessary to make the collocation be"full capacity", and adopting the matching skills of the seedling raising is the key technique to let "full capacity" butnot "over capacity" of the collocations.