Abstract: Changes of nutrient components in roots and shoots of rice for tolerant and susceptible varieties to Nilaparvata lugens (Stål) infestation were detected by using H₂SO₄ -H₂O₂ method at the tillering stage. For Xie you 963, N, P and K contents in roots and shoots at 3 d after 60 and 120 nymphs/plant infestation and N contents in roots and shoots at 6 d at the tillering stage did not show significant reduction. P contents in roots and shoots at 6 d, K contents in roots at 6 d, P contents in shoots at 9 d and K contents in roots and shoots at 9 d after 120 nymphs/plant infestation decreased significantly but 60 nymphs/plant infestation did not result in significant reduction of P and K contents; K contents in shoots at 6 d and N contents in roots at 9 d after 60 and 120 nymphs/plant infestation showed significant reduction. For Xie you 63, N contents in shoots at 3 d, P contents in roots and shoots at 3 d, N and P contents at 6 d and 9 d after 60 and 120 nymphs/plant infestation did not show significant reduction. N and P contents in roots at 6 d, K contents in roots and shoots at 6 d and N contents in roots at 9 d after 120 nymphs/plant infestation decreased significantly, but 60 nymphs/plant infestation did not result in significant reduction. K contents in roots and shoots at 3 d and 9 d and P contents in roots at 9 d after 60 and 120 nymphs/plant infestation showed significant reduction. The results showed that nutrient components in rice plants under N. lugens infestation varied with rice variety. Xie you 63 was more sensitive than Xie you 963. Reduction of K content was the highest, the next was P and the last was N. Roots were more sensitive to N. lugens infestation compared with shoots.

Key words: Nilapavata lugens, rice varieties, roots, shoots, nutrient components