5种矿物源药剂对苹果树腐烂病菌室内防效评价

Evaluation of the control efficacy of five mineral source pesticide against the plant pathogen of Valsa mali

为了筛选高效低毒且对苹果树腐烂病防效较佳的矿物源农药,本试验采用菌丝生长速率法、玻片孢子萌发法和离体枝条烫伤接种法,测定了5种矿物源药剂对苹果树腐烂病菌菌落生长和分生孢子萌发的抑制作用,以及其在离体枝条上的防治效果。结果表明,5种矿物源农药对苹果树腐烂病菌菌落的生长和分生孢子萌发均具有显著的抑制作用,当70%腐植酸钠GR、77%氢氧化铜WP、80%波尔多液WP、86.2%氧化亚铜WG和77%硫酸铜钙WP质量浓度分别为5、257、400、123和385μg/mL时,其对苹果树腐烂病菌菌丝生长的抑制率分别为97.55%、97.67%、98.94%、95.48%和98.43%,其EC_(50)分别为2.60、71.15、159.60、77.40和95.73μg/mL;对苹果树腐烂病菌分生孢子萌发的抑制率分别为96.33%、97.67%、98.67%、91.01%和95.58%,其EC_(50)分别为1.38、69.3、145.41、65.48和102.98μg/mL。离体枝条防效测定表明,5种矿物源农药中70%腐植酸钠GR对苹果树腐烂病防效最佳,为86.83%。因此,腐植酸钠可作为防治苹果树腐烂病的最佳矿物源农药。

The aim of our present study was to screen the highly effective and low toxicity mineral source pesticide for control of apple tree valsa canker disease. In this study, the inhibitory effects of five mineral source agents on colony growth and conidial germination of Valsa mail pathogens, and their control effect on detached shoots were determined by the colony growth rate, spore germination on slides and shoot scalding inoculation methods. The results showed that five kinds of mineral pesticides had significant inhibitory effects on the growth of V. mail and the germination of conidia. When the mass concentration of sodium humate 70% GR, copper hydroxide 77% WP, bordeaux mixture 80% WP, cuprous oxide 86.2% WG and copper calcium sulfate 77% WP were 5, 257, 400, 123 and 385 μg/mL, the inhibition rate on mycelial growth were 97.55%, 97.67%, 98.94%, 95.48% and 98.43%, and the EC50 values were 2.60, 71.15, 159.60, 77.40 and 95.73 μg/mL, respectively. The inhibitory rates on conidia germination were 96.33%, 97.67%, 98.67%, 91.01% and 95.58%, and their EC50 values were 1.38, 69.3, 145.41, 65.48 and 102.98 μg/mL, respectively. Among the five kinds of pesticides, sodium humate 70% GR had the best preventive effect on detached shoots with the efficacy of 86.83%. Therefore, sodium humate can be used as the mineral biological pesticides for controlling valsa canker disease on apple trees.