Study On The Age Standard And Quality Parameter Of The Plug Seedling Of Cucumber

As an advance technology, the technology of plug seedling which met the need of the industrialization of the seedling had a plentiful development in our country. To guiding the produce of the seedling and making progress in the technology of plug seedling, it is necessarily to do research on the quality standard of the plug seedling of cucumber, to give some stabile and feasible quantitative parameters which can evaluate the quality of the plug seedling exactly.In this article, the effect of three different densities on the growth of plug seedlmg of cucumber under artificial conditions was researched and the relations among 8 simple index, 4 relative index and 6 complex index regarded as seedling healthy index was analyzed with the Correlation Analysis and Path-coefficent Analysis, and some parameters about the quality of plug seedling was concluded. At the same time, the effect of 3 different seedling ages and 4 group same age seedlings with different quality on the growth of cucumber seedling after transplanted was researched to check the efficiency of the parameters. The conclusion was followed:1) Density had significant effect on the growth on the plug seedling of cucumber. With the increase of density, the distant between the seedlings was closer, the expanding of leaf was restrained, so the dry weight of seedling was decreased. The more light to get, the more dry matter was distributed to the stem and the petiole, the longer the stem and the petiole was.2) It is appropriate that the leaf area index of the plug seedling of cucumber was 1.60. To a flat with 72 plug, when the value of leaf area index was 1.60, the seedling age is the second true leaf was folded. After transplanted, compared with seedling with two leaves and seedling with tree leaves, the seedling with second true leaf folded had a better growth and a higher total output. So it is rational the seedling with the second true leaf folded is enough for transplant.3) The seedling healthy index used to evaluate the quality of seedlings in the past also can be used to evaluate the quality of the plug seedling, but considering the convenience and practicality of the index, X₁₄( (diameter of stem/height of stem)xfresh weight of shoot ) would be more suitable. With the value of complex index increase, the height of the stem, the diameter of stem, the number of the leaf and the largest area of the leaf increased too. The result of the correlation analysis between the value of seedling healthy index and the output was noticeable. It can indicate exactly the growth after transplanting. So it can be use to evaluate the quality of the plug seedling.4) The diameter of the stem and the fresh weight of shoot had a direct function on the quality of the plug seedling, the height of the stem had negative on the quality of the plug seedling. One the one hand, we can evaluate the elementary quality of cucumber seedling just by the status of the stem diameter, shoot size and stem height. On the other hand, we can efficiently improve the quality of plug seedling of cucumber through increasing the diameter of stem and the fresh weight of shoot and restraining the height of stem.