中文摘要：

在紫外辐射（UV-B）增强条件下,采用盆栽的方式,研究了苗期和开花期喷施不同浓度LaCl3溶液对大豆东农47蛋白质含量、脂肪含量和蛋脂总量的影响,并筛选出LaCl3溶液的最佳喷施浓度和喷施时期。结果表明：在UV-B辐射增强条件下,苗期所有浓度镧处理的蛋白质含量和蛋脂总量都减少,脂肪含量增加;其中30 mg.L-1LaCl3处理脂肪含量（22.80%）最高,较对照显著增加3.78%。开花期所有浓度镧处理的蛋白质含量和蛋脂总量都增加,除40 mg.L-1LaCl3处理外脂肪含量也都增加;其中40 mg.L-1LaCl3处理,大豆蛋白质含量（42.13%）和蛋脂总量（63.80%）最高,分别较对照增加4.46%和2.24%;60 mg.L-1LaCl3处理的脂肪含量（22.40%）最高,较对照增加1.50%。苗期和开花期各喷施60 mg.L-1LaCl3的大豆籽粒蛋白质含量（42.57%）最高,较对照增加0.64%;20 mg.L-1LaCl3处理脂肪含量（22.03%）最高,较对照增加0.46%。综合考虑,在UV-B辐射增强条件下,开花期喷施40 mg.L-1LaCl3溶液有利于提高大豆的品质。

英文摘要：

Enhanced ultraviolet-B （UV-B）radiation may have side effects on plant quality and,lanthanum（La） is reported to have protective potential on plants under adverse environment. In this study, soybean cv. Dongnong 47 was planted in green- house,24 h after sprayed with LaC13 solutions （ 0,20,30,40,50,60 mg·L^-1 ） at seedling, flowering and both stage, soybean plants were exposed to supplementary UV-B radiation. Seed protein content （ PC ）, fat content （ FC ） and their total content （PFC） were determined after harvest. All LaC13 sprayed at seedling decreased PC and PFC, while increased FC and, 30 mg·L^-1LaC13 significantly increased FC by 3.78%. LaC13 applied at flowering promoted PC, FC and PFC, except that of FC under 40 mg·L^-1LaC13 ,highest increment of PC（4.46% ） ,FC（ 1.50% ） and PFC （2.24%）were obtained at 40,60 and 40 mg·L^-1 LaC13 , respectively. At both seedling and flowering, spraying 60 mg·L^-1 LaCI3 increased PC by 0.64%, and 20 mg·L^-1 LaG13 increased FC by 0.46%. Results suggest under elevated UV-B irradiation, applying 40 mg·L^-1LaC13 at flower- ing will contribute to the improvement of total content of protein and fat in soybean.