Studies On Resistance Identification And Control Of Rice Varieties To Rice False Smut (Ustilaginoidea Virens)

The resistance identification and effect of the kinds of fungicide, the time of spray,the kinds of sprayer, etc. to false smut disease (Ustilaginoidea virens(Cooke)Tak.) ofrice were studied.1 The resistance degree of false smut disease were tested on 59 varieties of flee.The results showed that: the varieties amount of disease index＜0.1 were 13; 0.1≤disease index＜1 were 18; 1≤disease index＜2 were 12 and disease index≥2 were16.2 Two-line hybrid rice were susceptible than other rice. The disease was severityif the density of tassel grain or the angle of the top leaf with the stem were bigger. Thedisease severity was positive relation with the resistance of father line.3 The effect of 30%Armure EC 20ml/667m~2, 43% Horizon SC 15ml/667m~2,30%Armure EC 15ml/667m~2, 43%Horizon SC 12ml/667m~2 were 91.88%, 89.57%,86.24% and 85.84% respectively to fales smut disease of rice when the rice wastasseled before 6 days. Using Horizon 9,12,15ml/667m~2, could increased output25.6, 43.4and 55.5kg/677m~2 and extent of increased output were 4.72%, 8.01% and10.24% than CK respectively.4 The best time of spraying to false smut disease was when the leaf base distanceof top leaf and second leaf were zero. The different sprayer for control fales smutdisease were tested, the effect of machine sprayer was the best, the second wasWeishi-16P sprayer, the third was Gongnong-16 sprayer.5 The integration effect of growth density, nitrogen amount, using time ofnitrogen, spraying time and amount of fungicide to fales smut disease of rice weretested. The results showed that the best importance factor was spraying time, andsecond was using time and amount of nitrogen, the amount fungicide and growthdensity was unimportance.