Identification And Utilization Of The Sunflower Broomrape Physiological Race And The Broomrape-resistent Germplasm

Sunflower broomrape(Orobanche cumanaWallr.) is a kind of parasitic plant that currently represents one of the most serious production constraints in many sunflower producing countries around the world. It is reported that there are may be 25-32 sunflower broomrape physiological races, and there have been 8 virulent races identified as A- H. In recent years, sunflower breeders have made relevant contributions in breeding for broomrape resistance and have been successful in developing cultivars resistant to this parasite. However, the introduction of new resistance genes has been frequently followed by the occurrence of new virulent races overcoming their resistance.The purposes of this study were to identify sunflower physiological race, analyze the broomrape resistance of the different sunflower varieties and the breeding potential of broomrape-resistent germplasm. These results will provide a theoretical basis for the development of more durable sources of broomrape resistance and improve sunflower performance in areas infested by broomrape.At the same time, breeding resistant varieties and applying directly in production, control the dangers of sunflower broomrape in XinJiang province. The main results in this thesis are followed as below.(1) The identification of the sunflower broomrape physiological race showed that, the broomrape races were no. 4, no. 2 and 5 from regiment 72, agricultural division 4, regiment 183, agricultural division 10 in XinJiang production and construction corps, and XinJiang academy of agricultural and reclamation science, crop research institute respectively. Among them, the race from agricultural division 10 was the lowest race.(2) The identification of the resistance to broomrape of 40 sunflower varieties which come from sunflower lab of Crop Research Institute in XinJiang Academy of Agricultural and Reclamation Science showed that these 8 sunflower varieties, BH2-6521B、950C-1121132B、968261-241211R、9790-221111R、BH2-r452B、BH2-t141B、YZ0-14211R、YZ3-21 R are immune to 3 different broomrape groups.While the identification of the resistance of 18 oil varieties and 10 hybrid sunflower resistances in field showed that, JK102, JK103, BC11-3 and BC11-2 from Jilin baicheng are immune resources; and AR8-2020、AR8-2120、AR8-2220、AR8-2420、AR8-2520、AR8-1010、AR8-1011、AR8-1014、AR8-1015、AR8-1018、AR9-4142、AR9-4342、AR9-1610、AR9-1611、Xin kui-9 these 15 oil varieties recommended by XinJiang academy of agricultural reclamation cultivation are immune. These identified anti-broomrape sunflower varieties can be used for large areaes.(3) The analysis of the inheritance of resistance to broom rape in sunflower showed that, the broomrape resistance in sunflower was controlled by a single dominant gene, according with Mendel’s law.(4) According to the backcross breeding, embryo breeding and breeding in NanFan, the genetic heredity of the 10 susceptible restorers were improved, and 4 oil sunflower restorers were improved successfully(including RR1-61421 FR, 99RITMO-21131 R, XX1-211111 FR, and 98RITMO-231111R), 5 confectionary sunflower restorers were improved successfully(including XX2-w121R、BH2-k511R、XX2-p131FR、XX2-u111R、XX2-r142R). 16 hybridized combinations were prepared from the improved broomrape resistance restorers, among which 14 hybridized combinations contain resistance gene Or2 and immune to 183 regiment broomrape group.