Prevention and Controll of Diseases and Pest Damages of Siraitia grosvenori

[Objective] The aim was to develop prevention and control approaches of diseases and pests of Siraitia grosvenori. [Method] Long-term observation was con- ducted on cultivation methods of Siraitia grosvenori in the gardens in Longjiang Vil- lage of Yongfu County to conclude the prevention methods. [Result] Siraitia grosvenori yield can be reduced by nine diseases, such as root knot nematode dis- ease, and eight pests, such as Brachytrupes portentosus. [Conclusion] It would be effective for prevention of diseases and pests and guarantee quality and yield of Luohan guo to manage the gardens dominated by biological control and supple- mented by pesticide as per crop rotation.

Broccoli seedling pest damage degree evaluation based on machine learning combined with color and shape features

The degree of pest damage evaluation on corps in the field environment is very important for precision spraying pesticides.In this paper,we proposed an image processing method to identify the wormholes in the image of broccoli seedlings,and then to evaluate the damage of the broccoli seedlings by pests.The broccoli seedlings were taken as the research object.The ratio of wormhole areas to broccoli seedling leaves areas(Rw)was used to describe the pest damage degree.An algorithm was developed to calculate the ratio of wormhole areas to broccoli seedling leaves areas.Firstly,broccoli seedling leaves were segmented from the background and the area of the leaves was obtained.There were some holes in segmentation results due to pest damage and other reasons.Then,a classifier based on machine learning was developed to classify the wormholes and other holes.Twenty-four features,including color features and shape features of the holes,were used to develop classifiers.After identifying wormholes from images,the area of the wormholes was obtained and the degree of pest damage to broccoli seedling was calculated.The determination coefficient(R2)between the algorithm calculated pest damage degree and manually labeled pest damage degree was 0.85.The root-mean-square error(d)was 0.02.Results demonstrated that the color and shape were able to effectively segment wormholes from leaves of broccoli seedlings and evaluate the degree of pest damage.This method could provide references for precision spraying pesticides.

Genetically Engineered Corn Rootworm Resistance: Potential for Reduction of Human Health Effects From Pesticides

Objective and Methods Insecticide use, grower preferences regarding genetically engineered (GE) corn resistant to com rootworm (CRW), and the health effects of using various CRW insecticides (organophosphates, pyrethroids, fipronil and carbamates) are reviewed for current and future farm practices. Results Pest damage to corn has been reduced only one-third by insecticide applications. Health costs from insecticide use appear significant, but costs attributable to CRW control are not quantifiable from available data. Methods reducing health-related costs of insecticide-based CRW control should be evaluated. As a first step, organophosphate insecticide use has been reduced as they have high acute toxicity and risk of long-term neurological consequences. A second step is to use agents which more specifically target the CRW. Conclusion Whereas current insecticides may be poisonous to many species of insects, birds, mammals and humans, a protein derived from Bacillus thurigiensis and produced in plants via genetic modification can target the specific insect of CRW (Coleoptra), sparing other insect and non-insect species from injury.

Landscape changes have greater effects than climate changes on six insect pests in China

In recent years, global changes are the major causes of frequent, widespread outbreaks of pests in mosaic landscapes, which have received substantial attention worldwide. We collected data on global changes(landscape and climate) and economic damage caused by six main insect pests during 1951–2010 in China. Landscape changes had significant effects on all six insect pests. Pest damage increased significantly with increasing arable land area in agricultural landscapes. However, climate changes had no effect on damage caused by pests, except for the rice leaf roller(Cnaphalocrocis medinalis Guenee) and armyworm(Mythimna separate(Walker)), which caused less damage to crops with increasing mean temperature. Our results indicate that there is slight evidence of possible offset effects of climate changes on the increasing damage from these two agricultural pests. Landscape changes have caused serious outbreaks of several species, which suggests the possibility of the use of landscape design for the control of pest populations through habitat rearrangement. Landscape manipulation may be used as a green method to achieve sustainable pest management with minimal use of insecticides and herbicides.