在实验室条件下,测试了不同温度处理对离体南方根结线虫存活的影响,结果表明,在25、30、35℃和40℃下,杀死90%以上离体南方根结线虫分别需要30d(100%)、26d(96.6%)、24d(94.1%)和9d(99.6%),而45、50℃下则需要15min和2.3min。同时测试了不同温湿度处理对土壤中南方根结线虫存活的影响,结果表明,25、30℃是土壤中根结线虫的适宜温度,当土壤含水量为14%时,40d死亡率分别为91.1%、90.4%;35℃线虫处于抑制状态,40d死亡率为85.3%;而线虫对40℃以上的高温敏感,随着处理温度升高,杀死线虫所需时间缩短。根结线虫在不同温湿度下的死亡情况不同,土壤温度为25~35℃,土壤含水量为6%是线虫的适宜湿度;土壤温度达到40℃且含水量为6%和14%时,杀死100%根结线虫仅需4d,不利于其存活;而50℃的高温和含水量达18%的高湿更不利于其存活。
The effects of different temperatures on the survival of Meloidogyne incognita in vitro were tested in the laboratory. The results showed that the durations of over 90% nematode death at 25 ℃, 30 ℃, 35 ℃ and 40 ℃ were 30 d (100%), 26 d(96.6%), 24 d(94.1%) and 9 d(99.6%), respectively, while at 45 ℃ and 50 ℃, 15 min and 2.3min, respectively. The influences of different teleratures and moisture on the survival of M. incognita in soils were also evaluated. The results showed that the optimal temperature of M. incogn/ta in soils ranged from 25 to 30 ℃ and the mortality rate treated for 40 d with 14 % soil moisture were 91.1% and 90.4 %, respectively. The nematode was in inhibited state at 35 ℃ and the mortality rate was 85.3% after treated for 40 d. M. incognita was very susceptible to higher temperature when temperature was over 40 ℃. The time of killing nematodes was shortened with increasing treatment temperature; the mortality rate of M. incognita was different at different temperatures and moistures. The optimal survival conditions for M. incognita in soils were with 6% soil moisture content and temperature variation ranging from 25 to 35 ℃. In addition, the nematodes failed to survive when temperature in soil reached 40 ℃ and soil moisture under 6% and 14%. Besides, temperature over 50 ℃ in soil and soil moisture content over 18% were the worst conditions for M. incognita.