Coupling relationships of nursing seedling densities and finger sticking area by mechanized hybrid rice transplanter

In order to obtain the good quality of planted hybrid rice, nursing seedling density and finger sticking area were selected as two factors, and the tests of two factors with three levels were designed with hybrid rice 1596 as tested rice seed. The results showed that main indexes of qualities of nursing seedling, young seedling and field planted rice had significant correlations at level 0.05. T-test results of paired samples at level 0.05 showed that blank space ratios(or missing plant ratios) had significant differences for young seedling to nursing seedling, and for field planted rice to nursing seedling. Eligibility ratio of equality degree (ERED) for young seedling had significant differences to that of nursing seedling, and ERED for field planted rice had no significant differences to that of young seedling. The optimum test set nursing seedling density as 73 g per nursing tray and finger sticking area as 2.38 cm2, in this situation, blank space ratios (or missing plant ratios) and ERED of qualities of nursing seedling, young seedling and field planted rice were 1.1% and 92.5%, 2.6% and 90.2%, 5.1% and 88%, respectively, and target field rice plant was 541 665 per hectare.