Vo Quang Minh Head of GIS RS Lab
Cantho University,
Vietnam
Email: [email protected]
Researcher
Department of plant protection
cantho province
The potential risk of pest and disease damage to rice cops was studied at the Province level using a Geographic Information System (GIS) to monitor the relationship between environmental and climatic variables. Cantho City Province, Vietnam, was selected as the study area due to the occurrence of favorable conditions for potential outbreak hotspots of the Brown Backed Rice Plant Hopper, BBRP Hopper, (Nivaparvata lugens). Findings from this research investigated the need for village level surveillance of BBRP Hopper outbreaks, the level at which outbreaks are acknowledged to occur, as opposed to district level surveillance. The spatial relationships between climate and BBRP Hopper transmission was investigated using data collected from 120 different locations within the Trung An village, Thot Not district, Cantho city. A Global Positioning System (GPS) was used to record the spatial location of the data. Geostatistical software and a GIS were respectively used to analyse and interpolate, and then plot the data. Climatic evidence suggests that rainfall, maximum and minimum temperature, and relative humidity are causal aspects in the prevalence of the BBRP Hopper. Biological evidence supports the observed effects of climate; such as increased rainfall and higher humidity, resulting in a higher incidence, and thus frequency, of the BBRP Hopper. Rice plant factors, such as number of leaves and the stage of grain maturity, also influence the density of the BBRP Hopper. The density of BBRP Hopper was observed to change with the different stages and seasons for rice growth. The geostatistical analysis showed that the density of the BBRP Hopper was closely correlated with the aforementioned environmental factors. However, obtaining the climatic data at field or village scale can sometimes be difficult to lack of monitoring equipment; in this instance the use of interpolated climatic data is of great value.The use of GIS and other spatial analysis methods are extremely valuable for modeling the relationships in biological problems as has been demonstrated with the BBRP Hopper and contributing environmental factors. Crop-pest interactions will change significantly with climate change leading to an impact on pest distribution and crop losses. Given a significant population base of disease and insects within an area, increases in temperature and humidity create favorable conditions for population growth and thus substantial rice yield losses.
