【目的】研究1/4根域施用不同水平有机肥对西洋梨幼树生长量和光合特性的影响。【方法】用美国CID公司生产的Photosynthesis system CI-340型光合测定系统采用闭合式气路测定净光合速率;用日本MINOLTA公司生产的SPAD-502型叶绿素测定仪测定相对叶绿素含量SPAD值;10月下旬统计每株新梢的总数量、总叶片数及总长度;用叶面积仪测量叶面积,计算叶比重。【结果】20%有机肥处理新梢总叶面积、新梢生长量和净光合速率(Pn)均显著大于10%、30%处理和CK,而10%、30%处理和CK之间的差异不显著;新梢比叶重20%、30%的处理显著高于10%处理和CK,而两者之间差异不显著,10%处理的比叶重与CK差异不显著;3个处理的叶绿素含量略高于CK,但差异不显著,【结论】壤土局部施用适量有机肥可以提高西洋梨树体生长量和净光合速率(Pn),为西洋梨的高效栽培、果园土壤局部改良、集中营养供应等提供理论依据。
[Objective] The present study was conducted to evaluate the cold resis-tance of four cherry cultivars under different chil ing stresses. [Method] Four cultivars of Cerasus, Early-mahapphala, Red light, Lapins and Kashgar Kukan were selected as the experimental materials, and the changes of the relative electric conductivity （REC）, proline （PRO） content, malondialdehyde （MDA） content, superoxide dismu-tase （SOD） activity and peroxidase （POD） activity of dormant branches of the four cherry cultivars under low temperature stress were investigated. [Result] The REC of the four cherry cultivars was Kashgar kukan 〉 Red light 〉 Early-mahapphala 〉Lapins, while the MDA content was Kashgar kukan 〉 Early-mahapphala 〉 Red light 〉Lapins, both showed a rising trend in the four cultivars with the aggravating of the low temperature stress. The PRO content, POD and SOD activities of al cultivars were precisely contrary to their REC and MDA content, as al of them exhibited a sequence as Lapins 〉 Red light 〉 Early-mahapphala 〉 Kashgar kukan in al culti-vars, and got a trend of first rising and then declining. [Conclusion] Therefore, our final evaluation of cold resistance of the four cherry cultivars was Lapins 〉 Red light 〉 Early-mahapphala 〉 Kashgar kukan.
