Residual Film Pollution in the Eighth Division of the Xinjiang Production and Construction Corps

This study investigated the residual film content and distribution at different soil depths in the Eighth Division of the Xinjiang Production and Construction Corps.Before spring plowing in 2019,representative fields in four areas(Anjihai,Shihezi suburbs,Mosuowan and Xiayedi)were selected for residual film collection.The average content of residual film in the Eighth Division was 104 kg/ha.The residual film content in the four areas decreased in the order Anjihai>Shihezi suburbs>Mosuowan>Xiayedi.The average amount of residual film collected from cotton fields was greater than that from corn fields.Residual film content in the cotton field at soil depths of 0~10 and 10~30 cm was higher than that in the corn field,whereas the residual film content at a 30–50 cm soil depth in the corn field was higher than that in the cotton field.The results showed that farmers do not consider the long-term benefits,the high cost and short time of recycling,and the easy recycling of surface residual film.The shallow that the higher content of residual film,the less water in the soil of cotton.The same time,the results showed that the quantity of residual film in cotton field had greater influence on cotton quality.

Mating and reproductive characteristics of the pathogenic nematode Bursaphelenchus xylophilus

Pine wood nematode(B ursaphelenchus xylophilus),one of the most destructive invasive species,has caused extremely serious economic,ecological and social losses in many countries throughout the world.Since the high reproductive rate of B.xylophilus PWN is the main cause of rapid death of its pine hosts(Pinus spp.),understanding the reproductive and population biology and the ecology of this nmatode are of great importance.This study mainly focused on analyzing the mating process and population structure under different combinations of sex ratios for mating.Reproductive efficiency of B.xylophilus peaked when the sex ratio(female to male)was 3.4:1.Phases of the mating process for the different sex-ratio combinations indicated that B.xylophilus had evolved alternative reproductive strategies to cope with complex copulating conditions to obtain a suitable population structure for further propagation.This research provides fundamental information on the mechanism that is responsible for the rapid population growth of B.xylophilus.

Analysis on Content and Distribution of Residual Film in Fields of Different Crops

Before spring ploughing in 2019,the representative fields of the 8^(th) Division were selected,and residual film at different depths of soil in three areas of the 8^(th) Division was collected. Through the analysis on the weight and amount of residual film at different depths of soil,it was found that the average content of residual film in the 8^(th) Division was 104 kg/hm^2. From high to low,the content sequence of residual film in the three areas was Anjihai area,Mosuowan area and Xiayedi area. The average amount of residual film collected from the cotton field in the three areas was greater than that from the corn field. In the three areas,the content of residual film in the cotton field at the depth of 0-10 and 11-30 cm was higher than that in the corn field,while the content of residual film at the depth of 31-50 cm in the corn field was higher than that in the cotton field.