Abstract
In order to clear study the characteristic of seedling growth of Zoysia japonica as compared with Dactylis glomerata, the pot experiment was conducted under day/night temperature regimes of 34/29, 29/24, 24/19 and 19/14℃, respectively. 1. The rate of leaf appearance of Zoysia japonica was the highest at 34/29℃ plot and that of Dactylis glomerata was the highest at 29/24℃ plot. Comparing the growths of both grasses under these temperatures, the results obtained were shown as below. 1) The leaf appearance on main stem of Zoysia japonica was later than that of Dactylis glomerata untill the 3rd leaf of main stem appeared. After the 4th leaf appeared, the rate of leaf appearance was more rapid in tae. former. 2) The first tiller of Zoysia japonica appeared from the second leaf axil at 35 days after germination when 6 leaves expanded on main stem. On the other hand, that of Dactylis glomerata appeared from the first leaf axil at 25 days after germination when 4 leaves expanded on main stem. 3) C/F ratio of Zoysia japonica indicated 2.5 times as much as that of Dactyils glomerata. 2. Comparing the growths of Zoysia japonica among the temperature treatments, the results obtained were shown as below. 1) With a lowering the temperature from 34/29℃ to 19/14℃, the first tiller appeared more slowly and tiller numbers per plant decreased remarkably. 2) In 34/29℃ plot, the first elongated internode was observed in the 6th internode on the main stem at 49 days after germination, but appearance of the first elongated internode was markedly late with a decreasing temperature. The number of compound nodes and length of the stolon per plant were the most at 29/24℃ plot, however, they were markedly reduced at 24/19℃ plot. 3) The dry weights of leaf, stem and root were the heighest at 29/24℃ plot respectively, but all of them decreased with a decreasing temperature. Especially, the root weight was reduced, markedly. 3. Based on these results, we have discussed about the advisable method to make the seedling establish, survive and expand for the improvement of Zoysia type grassland.
