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1974年,阳江林场大面积引种洪都拉斯加勒比松(Pinus caribaea var handurensis)。全阳江林场共种植一万多亩,仅田畔分场就引种八千多亩。然而由于缺乏菌根等原因,在栽植后数月之内,便陆续死亡,不到一年的时光,全部死亡。罗琴分场亦种有二百多亩,由于苗木茁壮,自然感染大量的彩色豆马勃菌根真菌,成活率达97.4％。1975年5月初,保存率仍有94％,5月底以后,由于高温高湿,开始感染叶枯病。死亡日渐增多,该年底,保存率只有53％,1976年4月后降到45％。
In 1974, a large area of Yangjiang Forest Farm was introduced with Pinus caribaea var handurensis. All Yangjiang forest altogether planted more than ten thousand acres, only the field of sub-field on the introduction of more than 8000 acres. However, due to lack of mycorrhizae and other reasons, within a few months after planting, they gradually died, less than a year’s time, all died. Luo Qin sub-field also has more than 200 acres, due to seedlings robust, naturally infected with a large number of color bean papaya mycorrhizal fungi, the survival rate of 97.4%. Early May 1975, the preservation rate is still 94%, after the end of May, due to high temperature and humidity, began to spread leaf blight. The death toll has increased steadily, with savings rates of only 53% at the end of the year and 45% after April 1976.