摘要：
In order to investigate the effects of different cultivating densities on the growth and fruit quality of Malus pumila in northwestern Hebei Province,experimental plots with different cultivating densities were established in low mountainous area of Chicheng,Zhangjiakou municipality of Hebei.The results showed as follows.1) The plant height and current increment of density M5 (840 plant · m-2) was the largest and the weight of single fruit was the heaviest.Variations of the fruit longitudinal and transverse diameters,fruit shape index and fruit weight were basically the same with the changes of density.The crown and ground diameters and M4 (1 665 plant · m-2) were the largest.2) The fruit firmness of M3 (2 220 plant · m-2) was the highest,lowest for M5.Fruit titratable acid content of M1 was the largest,lowest for M5.Fruit vitamin C content of M2 was the highest,lowest for M4.The firmness,titratable acidity,and vitamin C content of the inner fruit were greater than those of the periphery part.Soluble sugar of M5 was the highest,lowest for M1.The sugar content of periphery fruit in each density was obviously higher than those of the inner part.Soluble solids content of M3 was the highest,lowest for M2.3) Correlation analysis indicated that the single fruit weight had a positive correlation with the fruit longitudinal and transverse diameters,and a negative correlation with titratable acidity and firmness.There was a positive correlation between titratable acidity and firmness.Through principal component analysis and comprehensive evaluation on fruit quality of different densities the fruit quality ranked as M5 inner ＞ M5 periphery ＞ M4 periphery ＞ M4 inner ＞ M2 inner ＞ M2 periphery ＞ M3 periphery ＞ M3 inner ＞ M1 inner ＞ M1 periphery.The results would provide the basis for determining the optimum cultivating density.%为了揭示密度对冀西北地区金红苹果生长及果实品质的影响规律,以张家口赤城县低山区不同密度金红苹果为对象,对其生长指标及其果实品质进行研究.结果表明:1)密度M5(840株·m-2)的金红苹果株高和当年生长量最大,M5单果重最大,果实纵横径、果形指数与果重随密度变化基本一致;密度M4(1 665株·m-2)的金红苹果冠幅和地径最大.2)密度M3(2 220株·m-2)的硬度最高,密度M5的硬度最低;密度M1(4 170株·m-2)的可滴定酸含量最高,密度M5的最低;密度M2(3 330株·m-2)的维生素C含量最高,密度M4最低;普遍内膛果实硬度、可滴定酸和维生素C都＞外围,而密度M5的可还原性糖最高,密度M1的最低,各密度外围含糖量明显＞内膛;密度M3的可溶性固形物含量最高,密度M2最低.3)通过对各项品质的相关性得出单果重量和果实纵、横径呈正相关的关系,和可滴定酸、硬度是负相关的关系;可滴定酸与硬度呈正相关;通过对不同密度金红苹果果实品质的主成分分析与综合评价得出综合品质排名:M5内膛＞M5外围＞M4外围＞M4内膛＞M2内膛＞M2外围＞M3外围＞M3内膛＞M1内膛＞M1外围,从而为确定最佳密度提供依据.
