Evaluation of Resistance of Different Kiwifruit Varieties (Lines) to Canker Disease and Brown Spot Disease

Kiwifruit canker and brown spot are significant diseases affecting kiwis,caused by Pseudomonas syringae patho-genic variations(Pseudomonas syringae pv.Actinidiae(Psa))and Corynesporapolytica(Corynespora cassiicola).At present,the research on canker disease and brown spot disease mainly focuses on the isolation and identification of pathogenic bacteria,drug control,resistance gene mining and functional verification.Practice has proved that breeding disease resistant varieties are an effective method to control canker disease and brown spot disease.However,most existing cultivars lack genes for canker and brown spot resistance.Wild kiwifruit resources in nat-ure exhibit extensive genetic diversity due to prolonged natural selection,containing numerous resistance genes.But,due to insufficient understanding of the resistance of most kiwifruit varieties(lines)to canker disease and brown spot disease,some high-quality resources have not been fully utilized.The incidence of canker and brown spot of 18 kiwifruit cultivars(lines)was measured by inoculating isolated branches and leaves,and their resistance to canker and brown spot was analyzed according to the length,disease index,mean diameter,and systematic clustering.The results were as follows:Among 18 different kiwifruit varieties(lines)for canker disease,there were two highly resistant materials,eight disease-resistant materials,four disease-susceptible materials,and two highly susceptible materials.Moreover,regarding brown spot disease,there were one highly resistant material,five dis-ease-resistant materials,four susceptible materials,and three highly susceptible materials.Furthermore,four resources were resistant to both diseases.The outcomes provided a theoretical basis for breeding kiwifruit against canker and brown spot.

New Records of Plant Distribution in Guizhou

Four new species were recorded in Guizhou Province,namely Sonerila trinervis Q.W.Lin,Mazus pulchellus Hemsl.ex Forbes et Hemsl.,and Hanceola exserta Sun.and Habenaria furcifera Lindl.

Study on the Repellent Effects of Different Grass Species on Raspberry Drosophila melanogaster

Large leaf mint(Agastache rugosus),white clover(Trifolium repens),spearmint(Mentha spicata),tall fescue(Festuca elata),orchardgrass(Dactylis glomerata)and alfalfa(Medicago sativa)were selected to perform sod culture,and the repellent effects of different grass species on adult raspberry Drosophila melanogaster were studied,so as to provide a scientific basis for grass cultivation in the control of raspberry fruit fly.The study showed that spearmint and big leaf mint had strong repellent effects on raspberry D.melanogaster,with repellent effects reaching 81.25%and 72.73%,respectively,and could be promoted as the main plant varieties in grassing orchards;and the next was alfalfa and white clover,which had the average repellent effects of 50.57%and 34.94%on D.melanogaster,respectively,and could be used as nectar plants to supplement the ecosystem of the sod culture orchards.