Effect of several management factors on the overwintering ability of Napier grass in southern Kyushu.

摘要

To maintain a high overwintering ability of Napier grass [Pennisetum purpureum] in S. Kyushu, Japan, the final cut needed to be carried out just before the first frost at about 20 cm height. The effects of sowing date were small. Differences in thepercentage of overwintered plants (POP) among years and altitudes were large. Cv. Merkeron had a superior overwintering ability to Wruk wona. The relationship between the minimum daily temperature during overwintering and POP was positive and logarithmicin Merkeron and Wruk wona. Analysis of meteorological data for Miyazaki Prefecture showed that Merkeron had POP exceeding 50% in more than half the areas in Miyazaki, even under the coldest winter of the seven years examined, suggesting its stable overwintering ability in S. Kyushu.