Screening And Identification Of Rose Germplasm Resources With Resistance To Black Spot Disease

Black spot disease is very common in open field cultivation,causing great losses to the beauty and economic benefits of roses.This study screened rose germplasm with strong resistance to black spot disease through field investigations,in vitro leaf infection experiments,and molecular marker experiments,providing important theoretical support for the establishment of a rose resistance system to black spot disease,and providing rich practical experience for the development of new rose varieties with excellent ornamental and disease resistance capabilities.1.Through field investigation of the diseased leaf rate of individual rose varieties,the disease levels were divided into five levels,namely: level 0(non diseased leaves)as a highly resistant variety,level 1(susceptible leaves below 10%)as a medium resistant variety,level 2(susceptible leaves 11% to 30%)as a low resistant variety,level 3(susceptible leaves 31% to 60%)as a susceptible variety,and level 4(susceptible leaves above 60%)as a highly susceptible variety.There are 39 varieties of rose resistant to black spot,including 8 varieties of wheat sparrow,green ink,Newman sisters,green calyx,ruby ice,Baden Memorial,20 S,and Lvye,the remaining 31 varieties such as Merang lipstick,daydream,Garivada,etc.are moderately resistant,63 varieties of low resistance such as Catol card,Saint Azebuja,and Taboo Senses,46 susceptible varieties such as Queko,colored chalk,Merang Capriccio,Smile,Tannick There are 20 high sensitivity varieties such as romantic bikers.The green varieties,such as Green Field,Green Ink,and Green Calyx,are all highly resistant to black spot disease.There is no significant correlation between other physiological traits and black spot resistance,and there is also a significant difference in disease resistance among different varieties.2.Based on the comprehensive analysis of the size and infection rate of the black spot after infection,a variety with a disease spot size of less than 2 cm and an infection rate of less than 0.35 mm/d is considered to have strong resistance,including Baden Memorial,Red Dragon,Macintosh,Wang Cheng,Sorido,Mini Da Vinci,President Hoover,Green Ink,Warrior,Green Calyx,20 S,Pink Dragon,Pink Fan,Kodes Celebration,Pink Dragon,Fire Peace,Merang Lipstick,Garibada,Cute Hot Cocoa,Grand Medal,Pink Panther,LOVE,Colorful Cloud 35 varieties of Rosa chinensis,including Mrs.Charlotte,Lvye,Newman sisters,Codes celebration,portrait,festival fireworks,pink piano,ruby ice,pink bell,Monte Carlo,red piano,Aloha,pink fan,have strong resistance to black spot disease.Through comprehensive field investigation and infection test,Meilang lipstick,Garivada,President Hoover,festival fireworks,Aloha,Mrs.Charlotte,Green Ink,Newman sisters,Lovely Hot Cocoa,Wang Cheng,Green Calyx,Red Dragon,Pink Piano,Ruby Ice,Pink Fan,Baden Memorial,Red Piano,Macintosh,Solito,LOVE,Lvye,20 S,Pink Dragon,and Curdes Celebration are selected as high resistance varieties.3.Through molecular marker technology,59 materials can be amplified into clear bands,including Pink Leopard,Samurai,Merang Lipstick,Daydream,Kaliwada,President Hoover,Grain Sparrow,festival fireworks,medallions,red bouquet,Pink Peace,Pink Dragon,Mrs.Charlotte,Kodez Celebration,Green Ink,Darcy,Newman sisters,Lovely Hot Cocoa,Wang Cheng,Green calyx,Red Dragon,Pink Piano,Toulouse,Red Piano Ruby Ice,Mystery,Baden Memorial,Macintosh,Princess Kantor,Sorido,Porti Shirley,Elizabeth,Aldans,Fragrance of Greece,Vermilion Double Glow,Tropical Rainbow,20 S,Glory,Spectra,Chaoyun,True Universe,LOVE,Sophie’s Rose,Colorful Cloud,Ella Velvet Ball,Aloha,Fisherman’s Friend,Alpine Snowy Mountain,Wine,Pink Wood Fragrance,Portrait,Adoration,Vichy,Pilgrims,Autumn Rouge Monte Carlo,Motok,Pink Fan,Greenfield.The results of field screening,black spot infection test and molecular marker test are mostly consistent,among which the results are resistant varieties such as Merang Lipstick,Garivada,President Hoover,festival fireworks,Aloha,Mrs.Charlotte,Green Ink,Newman sisters,Lovely Hot Cocoa,Wang Cheng,Green Calyx,Red Dragon,Pink Piano,Ruby Ice,Pink Fan,Cordes Celebration,Baden Memorial,Red Piano,Macintosh,Solito,LOVE There are 24 varieties,including Lvye,20 S,and Fenlong.Among them,the green varieties with flower colors,Lvye,Lvmo,and Lvxie,are all highly resistant varieties.There is no obvious pattern between other ornamental shapes and resistance performance.