Investigation and Identification of Fungal Diseases of Kiwifruit in Qiandongnan Prefecture

[Objectives]The paper was to investigate and identify the fungal diseases of wild and red heart kiwifruit in Qiandongnan Prefecture.[Methods]The pathogenic fungi were isolated from diseased leaves and fruits of wild and red heart kiwifruit by tissue separation method.DNA sequencing was carried out by using the sequence analysis of ribosomal r DNA-ITS region,and molecular evolutionary trees were built by using MEGA 4.0 software.Finally,the pathogenic fungi were classified and identified by combining morphological observation.[Results]The main fungal diseases were anthracnose caused by Colletotrichum gloeosporioides on wild kiwifruit,fruit anthracnose caused by C.acutatum on red heart kiwifruit,leaf soft rot caused by Fusarium incarnatum on red heart kiwifruit,and brown spot caused by Alternaria alternata on red heart kiwifruit.[Conclusions]The study may provide some theoretical basis for the control of kiwifruit diseases in Qiandongnan Prefecture.

Spatial Distribution Characteristics and Influencing Factors of Traditional Villages in Qiandongnan Prefecture

Taking the 409 traditional villages in Qiandongnan Miao and Dong Autonomous Prefecture announced by the Department of Housing and Urban-Rural Development of Guizhou Province from 2012 to 2019 as the research object,the distribution characteristics and influencing factors of the traditional villages was analyzed using ArcGIS 10.2 software and geographic proximity and other measurement methods.The results show that the spatial distribution of traditional villages in Qiandongnan prefecture presents an agglomeration pattern.The high-density distribution areas of traditional villages are Liping County,Congjiang County,Leishan County and Taijiang County.The distribution of traditional villages is mainly concentrated in the southern and central regions of Qiandongnan prefecture.The natural environment,social economy,national history and culture are the main factors affecting the spatial distribution of traditional villages in Qiandongnan prefecture.

Spatial Distribution Characteristics of Rocky Desertification in Qiandongnan Prefecture of Guizhou Province

Rocky desertification is a serious threat to socioeconomic development and the ecological security of karst areas. The control of rocky desertification has therefore become a major concern of both the Chinese government and local populations living in karst areas. In this paper, we used the national evaluation system for monitoring rocky desertification, and adjusted relevant indices. For example, we improved the system＇s base rock exposure index with Normalized Difference Rock index（NDRI）, substituted a soil erosion index for soil depth, and from these obtained the categories and spatial distribution of rocky desertification. We also studied the main factors and functional mechanisms of rocky desertification with consideration given to natural geographic conditions such as soil, physiognomy, elevation, slope and river network density, and, also human interference factors such as population density, GDP, population distribution, and from these got spatial distribution characteristics and influencing factors of rocky desertification in Qiandongnan prefecture. Results indicate that the primary soil types of rocky desertification in the research areas include yellow, limestone and paddy soils. These rocky desertification areas are more likely to contain limestone soil than purple soil, and least likely to contain paddy soil. The distribution of moderate or severe rocky desertification in areas with moderate to steep slope is 40%, where sloping agricultural land comprises a large proportion of the total. Rocky desertification is widely distributed in regions with precipitation between 1000–1200 mm, and this precipitation is the main factor causing greater soil erosion in limestone soil base and sloping agricultural areas. Moreover, desertification is closely related to the distribution of residential areas, population density, poverty and sloping agricultural land