【摘要】 由松针褐斑病菌Lecanosticta acicola(Th(?)m)sydow引起的松针褐斑病在我国南方引种的国外松林中为害严重,1982～1983年在福建沙县官庄林场的研究表明,病菌在病叶及病死叶中越冬,分生孢子只有在雨天才能释放。但日降雨量低于1.7mm时也不能释放。用人工模拟降雨淋洗病叶时,不论雨势大小和病叶上孢子形成的数量如何,都以淋洗开始15～30min时孢子释放量最大,1h后急剧减少,2h后继续缓慢下降。1983年3～11月,每隔5天采集感病湿地松针叶,用人工模拟降雨(6mm/h)淋洗30min,计算淋洗雨水中孢子数,结果表明在湿地松林分中,试验时间内病叶上都有孢子形成,但以4月下旬至5月中旬为最多,9～10月较多。分生孢子的寿命较短,在载玻片上室温下不超过45d,在5℃下不超过70d。更多还原

【Abstract】 Slash pine (Pinus elliottii) is severely damaged by brown spot disease fungus (Lecanosticta acicola) in southeast China. Observations in northern region of Fujian province show that the fungus passes winter on affected needles and died needles hanging on branches or fallen to the ground. Spore traping with slids indicate that conidia release only in raining days but won’t release days on when rainfall is less than 1.7mm. Examinations of rainwater collected under diseasetrees show the same result. Washing sporulated needles of slash pine with artificial rainfall (2.6 or 12mm/h.) indicated that maxium conidia releasing occurs during the first 15~30 min. of washing. Washing diseased slash pine needles collected from a plantation with artificial rainfall (6mm/h.) for 30 min. to ex amine sporulations of the fungus in nature from March to November in 1983 with 5℃ days intervals showed that conidia develop all the time with the maxium appearing from late April to middle May. The longivity of conidia on slids is not more than 70 days at 5. and 45 days at room temperature.更多还原