钾肥对黄花梨产量与品质的影响

以十年生黄花梨为试材,采用田间试验研究不同水平钾肥对黄花梨叶片物质代谢、果实产量与品质的影响.结果表明,在株施K2SO40.27kg～0.81kg范围,黄花梨叶片钾含量、chl.a、chl.b,chl.总量和chl.a/chl.b比值,游离氨基酸、可溶性糖和可溶性蛋白质含量均不同程度提高,丙二醛含量降低;黄花梨产量、果实硬度、维生素C、还原糖含量和糖/酸比值分别提高23.9%～68.6%,5.1%～11.3%,8.1%～11.7%,4.9%～12.6%和4.8%～22.2%,总酸量约下降,硝酸盐含量降低0.8%～4.7%.以株施K2SO40.81kg效果最好,显著提高了黄花梨叶片叶绿素、可溶性糖、游离氨基酸、可溶性蛋白质和钾含量,显著提高了果实硬度、Vc含量、还原糖含量和糖/酸比值,显著降低了叶片丙二醛.适宜增施钾肥能促进黄花梨生长发育,提高果实产量和改善品质.

Effects of Potassium Application on the Yield and Quality of Huanghua Pear

Ten-year-old Huanghua pear plants were used to study the effect of application of potassium on their leaf metabolism, yield and quality. The results indicated that application of potassium sulphate at rates of 0. 27 kg-0. 81 kg/tree increased, to different extents, the content of potassium, chlorophyll a, chlorophyll b, total chlorophyll, chl. a/chl, b ratio, total free amino acids, water-soluble sugar and water- soluble protein, and decreased MDA in the leaves; frult yield, flesh firmness, the contents of vitamin C and reducing sugar and the sugar-acid ratio were improved by 23.9%-68. 6%, 5.1%-11.3%, 8. 1%- 11.7%, 4.9%-12.6% and 4.8%-22.2%, respectively, while the total acid decreased and nitrate decreased by 0. 8%--4. 7%. The best treatment was application of K2SO4 at 0.81 kg/tree, which remarkably enhanced the chlorophyll content , total free amino acids, water-soluble sugar, water-soluble protein and potassium content of the leaves, improved flesh firmness, vitamin C content, reducing sugar content and the sugar-acid ratio of Huanghua pear, and obviously decreased MDA content of its leaves. It is hence concluded that potassium application at appropriate rates can improve the growth and development of Huanghua pear and enhance its yield and quality.