陆良县位于云南东部,南盘江中游上段,海拔1,840—2,600米,是高原平坝兼山区的县。年平均气温15℃,年降雨量1,000毫米左右,无霜期260天。气候特点是:冬春两季干旱不雨,夏秋两季降雨集中,夏无酷暑,冬无严寒。当地广大贫下中农创造了一年三季马铃薯栽培经验,有效地防止了马铃薯种薯退化。一、什么叫一年三季马铃薯栽培 Luliang County is located in the eastern part of Yunnan, the upper reaches of Nanpanjiang River, 1,840-2,600 meters above sea level, is the plateau and mountain counties. The annual average temperature of 15 ℃, the annual rainfall of about 1,000 mm, 260 days frost-free period. Climatic characteristics are: winter and spring drought does not rain, summer and autumn rainfall concentrated, no summer heat, no winter cold. The vast majority of poor and middle-income peasants in the area have created potato cultivation experiences in three seasons a year, effectively preventing the degradation of potato seed. First, what is the year three quarters of potato cultivation