Study On The Occurrence And Control Methods Of Allium Chinense Root Mites In Jinshi City

Root mite was one of the main underground mites in the production process of Allium chinense in Baiyi Town,Jinshi City.It damages the underground bulbs of Allium chinense and causes death of Allium chinense,which has brought great losses to the local production of Allium chinense.Because of its small size,and the damage site is the underground bulb of Allium chinense,it was difficult to be found and controlled.Local farmers have no effective control measures,which seriously limits the development of local Allium chinense industry.This study systematically investigated the occurrence and control methods of root mites on Allium chinense in Jinshi,and identified that the root mites on Allium chinense in Jinshi were Rhizoglyphus robini.The occurrence of Robin mite in all growth stages of Allium chinense in Jinshi was investigated and the damage degree of Robin mite was graded according to the yield reduction ratio.The experiment of soil film combined with seed treatment to control Allium chinensis root mites in dryland was carried out in high temperature season,and the soil bacterial diversity index after film treatment and control treatment was detected and analyzed.The main results of this study are as follows:1.The root mites collected on Allium chinense in Baiyi Town of Jinshi City were made,and the accurate species could not be determined by microscopic examination.Through amplification and sequencing of the COXI gene of root mites,the similarity between the sequence and the R.robini sequence(KJ152745.1)was 100%,which was determined to be R.robini of Acaridae.2.Root mites were distributed irregularly in the field,and there was no obvious gathering point;damage can occur when the temperature reaches above 15°C,and the occurrence of root mites in the growth period of Allium chinense increases with the increase of temperature,in April local time,when the average temperature reached above 20°C,the occurrence trend was to increase,and in mid-May local time when the average temperature reached above 33°C,the occurrence of root mites in the field gradually leveled off;the occurrence amount and occurrence rate of the root mites in the dry field were higher than those in the paddy and drought rotation fields;the occurrence rate of root mites in the main producing areas of Allium chinense during the harvest period was 38.4%,and the serious occurrence rate was 40%.The humidity of storage area was closely related to the occurrence of root mites.The occurrence of root mites was serious in storage areas with high humidity,whereas on the contrary,it was lighter.The occurrence and incidence of root mites in dry field were higher than those in paddy-dry rotation field.The occurrence rate of root mites in the main producing areas of Allium chinense was 38.5% and the occurrence severity rate was 40%.The humidity of storage site is closely related to the occurrence of root mite.The occurrence of root mite in storage site with high humidity is serious,and vice versa.According to the yield reduction ratio of Allium Chinense caused by root mite damage in the field,the damage degree of root mite is rated as none(no occurrence),slight(yield reduction ratio of 5% and below),moderate(yield reduction ratio of 6%to 20%),severe(yield reduction ratio of 21% to 50%),serious(yield reduction ratio of 51% to 70%)and unusually serious(yield reduction ratio of 70% and above).3.The combination of blue film soil treatment and seed soaking treatment had the best control effect on the root mites of Allium chinense in dry land.The average carrying rate of Allium chinense planted in this combination was 0.08%,and the average number of mites per plant was 0.14;the root mite occurrence was the most serious in the planting combination of the control treatment soil and the control treatment seed.In this combination,the average mites carrying rate was 96.26%,and the average number of mites per plant was 29.40.There was no significant difference in field growth between chitosan coated seeds and other treatments(P > 0.05).There was no obvious advantage in the control effect of root mites compared with single soaking seeds.There were significant differences in soil bacterial Richness between the two mulching treatments and Shannon and control treatments.There was no significant difference in soil bacterial Richness and Shannon between the two mulching treatments.The soil treated with mulch film had an effect on soil bacteria Richness and Shannon.