1沤根1.1症状表现。该病发生后,芹菜不再长新根,幼苗生长缓慢,幼根外皮变成锈褐色,以后逐渐腐烂。茎叶生长受抑制,最后枯死,枯死幼苗很容易从土中拔起。1.2发病条件。在冬季、早春季节,芹菜苗期遇长期阴雪天气,苗床温度过低(低于10℃),湿度过大,导致根系发育不良,吸收能力下降 1 沤 root 1.1 symptoms. After the disease, celery is no longer new roots, seedlings grow slowly, the root sheath becomes rusty brown, and then gradually decay. Stem and leaf growth inhibition, the last dead, dead seedlings easily from the soil uprooted. 1.2 onset conditions. In winter and early spring, when celery seedling encounters long-term overcast and snowy weather, the seedbed temperature is too low (below 10 ℃) and humidity is too high, resulting in poor root development and decreased absorption capacity