Abstract:

In this study, we determined the content of soluble sugar, total sugar, soluble protein, total nitrogen, free amino acids and crude fat in needles of various masson pine families, which have different resistance to Hemiberlesia pitysophila, to investigate the relationship between this nutrient content and the resistance of masson pines against the scale. The result showed that: 1)The content of total nitrogen in needles of high resistant families was lower than that in middle resistant families and low resistant families; 2) After being induced with injury by the scale, the content of soluble sugar and total sugar reduced, and the induced reaction was not correlated with families’ resistance; 3) The content of soluble protein, total nitrogen and total amino acids reduced with the soale injury. The induced reaction was positively correlated with families’ resistance, that is, the content reduction in high resistance families was greater than that in low resistance families, so that the content of soluble protein, total nitrogen and total amino acids in needles of high families was lower than that of low families after being injured by the scale; 4) The content of 16 amino acids in needles of high families was lower than that of low families after being damaged by the scale; 5) The content of crude fat and the ratio of total sugar to total nitrogen were not correlated with the resistance of masson pine against the scale.

Key words: ^{Pinus massoniana,} Hemiberlesia pitysophila, insect resistance, nutrient