美国黑李引种试验

对美国黑李进行引种试验，结果表明。美国黑李适应本地区气候条件生长，并筛选出早熟品种李王、中熟品种黑琥珀、晚熟品种黑宝石和皇家宝石等4个优良品种，其3年平均树高、地径、冠幅、单株产量和产量分别达到3．40m、5．18m、1．74m^2、22．3kg、1255kg／667m^2，比对照提高1．3倍、1．48倍、1．6倍、7．88倍和7．94倍，充分显现出良种的优势，值得推广。

An Experiment of the Introduction of American Plums

The experiment indicates that the growth of American plums are suitable to the local climate, the 4 varieties including the American plums early-maturing variety King of Plum, the medium-maturing variety Black Amber, the late-maturing varieties Black Precious Stone and Royal Precious Stone are screened out. The three-year-old average high, diameter at foot, crown diameter, single output and output per mu reach 3.4 m, 5.18 cm, 1.74 m~(-2), 22.3 kg, 1 255 kg and is 1.3 times, 1.48 times, 1.6 times, 7.88 times and 7.94 times higher than the control group respectively. The varieties are worth extending because of the fine performance.