库尔勒香梨叶片组织结构对PP333的响应（英文）

Response of Leaf Tissue Structure to PP333 in Korla Fragrant Pear

[目的]探讨不同浓度的PP333处理对库尔勒香梨叶片组织结构的影响,为库尔勒香梨的栽培调控奠定基础。[方法]采用石蜡切片法观察不同浓度的PP333处理后库尔勒香梨叶片解剖结构的变化,测量其叶片厚度、表皮厚度、栅栏组织厚度和海绵组织厚度,计算栅海比、叶片组织结构紧密度和叶片组织结构疏松度,分析不同生长抑制剂处理后叶片组织结构的变化。[结果]与对照相比,PP333处理后,叶片厚度、栅海比和栅栏组织厚度显著增加。PP333处理对叶片表皮的影响不明显。2 500mg/L PP333处理使叶片厚度和栅栏组织厚度增加最多。1 500 mg/L PP333处理后,叶片组织结构紧密度最高。生长抑制剂处理后,叶片海绵组织和叶片组织结构疏松度降低,2 000mg/L PP333处理的SR最低。[结论 ]不同浓度生长抑制剂处理均增大了叶片厚度、海绵组织厚度、叶片组织结构紧密度和栅海比,减小了海绵组织厚度和叶片组织结构疏松度。喷施1 500 mg/L PP333可应用于库尔勒香梨的栽培。

[Objective] This study was performed to explore the effect of different concentrations of PP333 on leaf tissue structure of Korla fragrant pear and to lay the foundation for the cultivation and regulation of Korla fragrant pear. [Method] The leaf tissues treated with different concentrations of PP333 were dehydrated with al- cohol, embedded in paraffin and sliced into 10-μm slices. The thicknesses of leaf blade, upper epidermis, lower epidermis, palisade tissue and sponge tissue were measured, and the ratio of palisade to spongy layer thickness, cell tightness （CT） and cell looseness （CL） were calculated. [Result] The thickness of leaf blade, the ratio of palisade to sponge layer thickness and the thickness of palisade layer were all significantly increased after treatment with PP333. Treatment with 2 500 mg/L PP333 showed no obvious effect on the thickness of leaf epidermis, but increased the thicknesses of leaf blade and palisade tissue. Leaf CL was the highest in the treatment of 1 500 mg/L PP333. [Conclusion] PP333 can increase the leaf thickness, palisade tissue thickness and CT, reduce spongy tissue thickness and CL of Korla fragrant pear. Additionally, 1 500 mg/L was the optimal concentration for the application of PP333 to improve the cold resistance of Koda fragrant pear.