Analysis Of Heterodera Glycines Virulence Phenotype And Soybean Cultivars Resistance In Heilongjiang Province

The soybean cyst nematode(SCN),Heterodera glycines Ichinohe,was a serious plant pathogenic nematode which caused huge economic losses of the soybean(Glycine max L.)production in China and around the world.Using resistant cultivars was the most economical and effective approaches of SCN management.This study examined the occurrence and distribution of SCN and characterized HG Types.This study also assessed the resistance of major commercial soybean cultivars against SCN and investigated the genetic resistance of Kangxian 12.The following research results were obtained:1.Distribution and characterization of Heterodera glycines virulence phenotypes of Heilongjiang in ChinaAmong the 2015 samples,62 populations were classified to race and HG Type.A total of 11 HG Types were identified,including HG 0,1.2.3.5.7,1.2.3.7,1.3.4.7,1.3.7,2,2.5.7,2.7,6,6.7,7.In addition to HG 7 and 1.3.7,the other 9 HG Types were first reported in Heilongjiang province.HG Type 7 represented 45.16% of the sampled populations.HG Type 0 was the second most common virulence phenotype,comprising 30.65% of the populations.12.9% were virulent on PI548402 of SCN populations with a range of 10–48.99.PI548316 of SCN populations with a range of10-65.86.4.84% of the sampled populations on PI437654 were virulent.The relatively little reproduction of PI437654 was foud in this study.PI437654 had the lowest number of SCN populations with FI>10%.Five race was found: race 1,race 3,race 4,race 6 and race 14.Race 3 was most common and represented 64.52% of the populations.The relationship between race and HG Type of soybean cyst nematode was discussed.The relationship between race and HG Type of soybean cyst nematode was discussed.The SCN virulence type of Anda was HG Type 1.3.4.7(race 14)and Daqing was HG Type 7(race 3).2.Soybean cultivars evaluated for reaction to Heterodera glycines populations110 soybean cultivars were to evaluated to the resistance of HG Type 7(Race 3)and HG Type 1.3.4.7(Race 14)in the greenhouse.There were 5 soybean cultivars were resistant to HG Type 7(Race 3),accounting for 4.55% of the total.19 lines were moderately resistant,accounting for 17.27% of the total.The number of HG Type 7(Race 3)with moderately susceptible(63)and susceptible(23)was 86,accounting for78.18% of the total.2 were resistant to HG Type 1.3.4.7(Race 14),accounting for1.83% of the total.The six cultivars were moderately resistant,accounting for 5.50% of the total number;The rest of the cultivars is moderately susceptible and susceptible.Kangxianchong 12 and the other six cultivars have resistance to HG Type 7(Race 3)and HG Type 1.3.4.7(Race 14).The effect of H.glycines on yield of susceptible(Hefeng 50)and resistant(Kangxianchong 12)soybean cultivars was assessed in two naturally infested fields.Although no obvious aboveground symptoms were visible in the first infested fields,mean yield was 22.94% greater for Kangxianchong 12 compared with Hefeng 50.The yield of Kangxianchong12 increased by 33.35% in plots compared with Hefeng 50 in second field.3.Inheritance of soybean cyst nematode resistance in two new cultivars source,Glycine max Kangxianchong 12 and Qingdou 13We have investigated the genetic resistance to SCN HG Types 7 and 1.3.4.7(races 3 and 14)in Kangxianchong 12 and Qingdou 13 in the greenhouse.Kangxianchong 12 was rossed to ‘Hefeng 50',a domestic susceptible cultivar to generate F1 hybrids,210 random F2 individuals,and 210 F2:3 families.Meanwhile,336 F2:3 families were obtained designated as Qingdou 13 was rossed to ‘Hefeng50'.The 336 F2:3 progenies in Hefeng 50×Qingdou 13 showed a segregation of 4:332(R:S)for response to both HG Types 7 and 1.3.4.7(Races 3 and 14).The Chi-test square analysis showed SCN resistance from Qingdou 13 fit a one dominant and 3 recessive gene model(Rhg rhg rhg rhg).Chi-test square(?2)analyses showed resistance from Kangxianchong 12 to HG Type 1.3.4.7(race 14)in F2:3 were conditioned by one dominant and two recessive genes(Rhg rhg rhg)and resistance to HG Type 7(race 3)was controlled by three recessive genes(rhg rhg rhg).Kangxianchong 12 have the broad-based resistance to SCN originated from peking according to parental genetic pedigree analysis.4.Genome wide variations of Kangxianchong 12 by whole genome resequencingIn order to reveal the whole genome genetic type and resistance mechanism of the Kangxianchong 12,high-throughput resequencing technology was adopted to carry out whole-genome resequencing of soybean varieties resistant to Kangxianchong12,and the sequencing depth was 33.47 x.A total of 1974863 SNPs,241356 indel,17067 SV and 12941 CNV were detected.The data was annotated to 30 items by GO analysis.The data was enriched in 20 metabolic pathways such as plant hormone signal transduction when comparison with the KEGG database.These pathways and their related genes may play an important role in the resistance to SCN.CNV analysis of rhg1 locus further confirmed that the broad-spectrum resistance mechanism of Kangxianchong 12 was related to the copy number variation of rhg1 loci.Kangxianchong 12 required rhg1-a and Rhg4 for SCN resistance.Gm NPR1-1,Gm ACS9 b,Gm SAMT1,Gm PAD4 and Gm EDS1 may be associated with SCN resistance of Kangxianchong 12.The association with rhg1 locus in resistance genetic analysis needs further study.5.Screening and verification resistance-related genes of Kangxianchong12 under stress of the soybean cyst nematode Heterodera glycinesIn the present study,ten candidate reference genes(ELF1A,ELF1 B,CYP2,UBC4,UBQ10,TUB4,G6 PD,ACT2/7,ACT11,and CONS4)were evaluated and their expression stability was analyzed in resistant variety soybean roots infected by SCN.All the data were statistically analyzed using ge Norm,Norm Finder,Best Keeper and Ref Finder.The results showed that ELF1A(Glyma.05g114900)and UBC4(Glyma.18g216000)were the most stable genes.ELF1 A and UBC4 were selected as double internal reference.In addition,the relative expression of five resistance-related genes were evaluated by RT-q PCR.The results showed that 5 genes were significantly expressed.The relative expression of Gm EDS1 was the highest,10.43 times higher than control and other genes were Gm NPR1-1(6.79),Gm ACS9b(2.3),Gm SAMT1(8.86),Gm PAD4(5.54).The results showed that two reference genes were used as reference genes correction and the five resistance-related genes may play an important role of Kangxianchong 12 infected by SCN.