梨小食心虫不同寄主植物中苦杏仁苷含量的季节性变异

Seasonal Variation of Amygdalin Content in Different Host Plants of Grapholitha molesta

以4—8月的桃梢、梨梢、苹果梢、桃果、梨果和苹果为试材,采用超声波辅助提取和高效液相色谱等方法,研究了嫩梢和果实中苦杏仁苷含量的变化,以期为明确梨小食心虫寄主植物中苦杏仁苷的分布特点及其时间动态变化提供参考依据。结果表明:桃梢中的苦杏仁苷含量(3.14mg·g^(-1))远高于苹果梢(0.28mg·g^(-1)),而梨梢中未检测到苦杏仁苷。3种寄主植物果实中的苦杏仁苷含量均呈先增加后减少趋势,6月均达最大值,桃、梨和苹果分别为0.86、0.51mg·g^(-1)和0.43mg·g^(-1)。在5—6月,梨果和苹果中检测不到苦杏仁苷或含量显著低于桃果。7—8月,梨果和苹果中的苦杏仁苷仅少量存在,桃果中未检测出。桃梢中的苦杏仁苷含量显著高于桃果,苹果梢中的苦杏仁苷含量显著高于5、7月和8月的苹果。聚类分析可将寄主植物划分为3类,第一类仅包括4月的桃梢,第二类仅包括6月桃果,第三类包括其它寄主植物。不同寄主植物中测得的苦杏仁苷含量具有明显的季节性差异。在季节早期,桃树幼虫可食部位含有较多的苦杏仁苷。在季节后期,梨树和苹果树幼虫可食部位含有较多的苦杏仁苷,但低于季节早期的桃树。

The tender shoots and fruits of peach,pear and apple in April to August were used as materials,the ultrasonic-assisted extraction and high performance liquid chromatography were used to study change of the content of amygdalin in shoots and fruits,in order to provide reference for the distribution characteristics of amygdalin and its dynamic changes of content with time in the host plants of G.molesta.The results showed that the content of amygdalin in peach tender shoots(3.14mg·g^(-1))was much higher than that in apple tender shoots(0.28mg·g^(-1)),but amygdalin was not detected in pear tender shoots.The contents of amygdalin in fruits of different host plants increased at first and then decreased,and reached the maximum in June,which in fruits of peach,pear and apple were 0.86mg·g^(-1),0.51mg·g^(-1)and 0.43 mg·g^(-1),respectively.In May and June,amygdalin was not detected in pears and apples,or significantly lower than in peaches.In July and August,only a small amount of amygdalin was found in pears and apples,while amygdalin was not detected in peaches.The content of amygdalin in peach tender shoots was significantly higher than that in peach fruits,and the content of amygdalin in apple tender shoots was significantly higher than that in apple fruits of May,July and August.Host plants were divided into three groups by cluster analysis,the first group only included peach tender shoots in April,the second group only included peach fruits in June,and the third group included the rest of host plants.Therefore,the content of amygdalin measured in different host plants had obvious seasonal difference.In early season,larval edible parts of peach trees contained more amygdalin than pear and apple trees.In late season,larval edible parts of pear and apple trees contained more amygdalin than peach trees,but lower than peach trees of early season.