Creation Of Wheat Cultivars For Resistance To Fusarium Head Blight And Analysis Of Resistance Sources

Fusarium head blight?FHB?is a devastating serious disea se caused by Fusarium graminearum to wheat production,resulting in reduced wheat yield,deteriorating quality and threatening food security.The easiest,safe,and cost-effective way to solve the problem of wheat head blight is to cultivate and grow varieties resistant to scab.Sumai 3 is currently the best germplasm resource of resistance,however,due to the differences in the traits such as plant type,leaf phase,panicle type,and grain between the wheat variety of the Huanghuai wheat tract,the Sumai 3 is more difficult to genetically improve in breeding and utilization,and has many burden traits.There is an urgent need to discover new and innovative fusarium head blight resistance materials in the breeding of Huanghuai wheat area.In t his study,F2:3population constructed with CIMMYT?International Maize and Wheat Improvement Center?artificially produced scab resistant material CM27 and domestic variety Zhoumai 22 and 423domestic and foreign wheat cultivars?lines?were used for field resistance identification of scab,combined with SSR molecular identification and agronomic analysis,breeding resources materials with excellent scab resistance and excellent agronomic traits were selected.The main results are as follows:1.In this study,the F_2:3 population was identified for resistance to head blight.The results showed that CM27 was susceptible to head blight?CM27 has been identified as very lightly in the area of inflecting fusarium head blight servely for many years and belongs to the moderate resistance type?,Zhoumai 22 was highly susceptible to head blight.There were no materials were immune to head blight in F_2:3 population and there were significant differences in the degree of disease among different strains.There were 32 materials above the moderate susceptible level,S52,S114 and S178 reached the moderate resistance level,and the disease index was 22.2,22.5 and 22.5,respectively.2.The analysis of percentage of diseased spikelet and agronomic traits in the F_2:3population revealed that the spikelet percentage was significantly negatively correlated with the panicle length,negatively correlated with plant height,and positively correlated with the flowering date.The variation of plant height and spike stalk in the population,with variation range 70¹32 cm and 8.27¹8.50 cm.The heading date and flowering date of Zhoumai 22were about 7 days later than that of CM27,and the variation range of population was about10 days.32 disease-resistant materials were initially screened out,of which 17 materials with agronomic traits close to Zhoumai 22.They were S4,S10,S14,S15,S17,S19,S33,S35,S37,S60,S66,S81.S108,S114,S122,S178,and S199.3.CM27,Zhoumai 22 and their F_2:3 populations were detected with the molecular markers Xgwm 493 and Xgwm 533,which were closely linked to the Fhb1 gene.The results showed that CM27 carry the Fhb1 gene and Zhoumai 22 did ont carry the Fhb1 gene.Only4wheat materials found in 200 populations contain Fhb1 gene,S52?S114?S135 and S162,respectively.The coincidence rate between molecular marker test results and field head blight resistance was low,indicating that resistance to head blight in the population may not be from Fhb1.The reliability of current molecular marker of the Fhb1 gene is not high,and it is speculated that CM27 may contain a scab-resistance gene different from Fhb1.4.79 wheat cultivars?line?in Huanghuai district were identified for resistance to head blight.It was found that the resistance to head blight was generally poo,most of the materials were susceptible to head blight,There are 29 cultivars?lines?above the moderate susceptible level,of which Zhengmai 136,Shengmai 101,Vomai 1212,Zhumai 305 and Xinong 501have reached the mid-resistance level and can be used for breeding research.The plant heights of the wheat varieties?lines?in the trials were generally short.By molecular marker testing,found that most of the regional test materials lacked disease-resistance genes.It is estimated that the varieties resistant to scabs are still lacking in future production.The remaining 344 domestic and foreign wheat varieties?lines?have been identified by Yangling for many years in the field and no scab was found.5.423 wheat varieties?lines?were tested by molecular markers,found that most of the tested materials lacked resistance genes.Only 38 wheat varieties?lines?were carrying the Fhb1 gene,including 9 region test materials,Zhengmai 136 reached the moderate resistance level,Xinong 511,Pingan 0518 and Fengdecunmai 16 reached the moderate susceptible level,Zhongnongmai 4007,Zimai 19,Zhengmai 132,and Luomai 26 and Wanfeng 269 were highly susceptible to scab.Only 6 PFT-I and HIS-I haplotype wheat lines?lines?were identified by PFT-CAPS and HIS-InDel specific markers.They were Ningmai 9,Ningmai 13,Chuanmai107,Salmone,Norin 61 and Kanto.58 wheat cultivars?lines?were screened for pedigree analysis and found that the cultivars?lines?had very few and single source of r esistance to scabs.The selected cultivars?lines?can be used to further identify the resistance,and prepare for the selection of high-quality breeding parents for resistance to scab.