Evaluation Of Agronomic Traits And Blast Resistance Of 85 New Materials Of Rice Three-line Sterile Lines

As one of the main food crops in China,the yield and quality of rice are closely related to national food security.Rice disease is one of the important factors affecting rice yield and quality,among which rice blast is the most obvious.Production practice shows that breeding and planting disease-resistant varieties are the most economical and green means to control rice diseases.In this paper,85 new materials of rice three-line sterile lines created by the Rice Disease Research Group of Sichuan Agricultural University were selected for research,Through fertility,agronomic traits,field resistance investigation and bud rate test,new sterile lines with high quality and disease resistance were screened out,and new hybrid rice combinations with utilization prospects were screened out.The results are as follows :The results of pollen microscopic examination showed that the fertility of 27 materials was between 0.5 % and 10 %,and the fertility of 58 materials was completely abortive.The results of rice blast resistance identification in the field showed that 37 materials showed moderate resistance and above to leaf blast,41 materials showed moderate resistance and above to panicle neck blast,and 7 materials(7021B,7023 B,7033B,7037 B,7039B,7153 B,7179B)showed resistance to both leaf blast and panicle neck blast.According to the quality standard of high-quality rice(GB / T17891-2017),10 of the 58 maintainer lines corresponding to the new sterile lines of rice with good fertility reached grade 3,14 reached grade 2,and 8 reached grade 1.The seed germination rate of 47 materials was higher than 80 %,and the seed germination rate of 5 materials was higher than 90 %.A total of 14 materials with moderate resistance(MR)and above,germination rate higher than 80 %,and appearance quality of grade 3 and above were screened : 7021 A,7023A,7033 A,7035A,7037 A,7045A,7049 A,7055A,7083 A,7085A,7097 A,7099A,7143 A,7179A.Five new male sterile lines 7021 A,7023A,7033 A,7035A and 7037 A with good quality,disease resistance and high combining ability were tested by using 142 single spore strains of Magnaporthe grisea.The results showed that the disease resistance frequency of the five materials was more than 65 %,showing a broad resistance spectrum,indicating that the five new materials of sterile lines had good resistance to the rice blast fungus population in Sichuan rice area,and had a good application prospect for further breeding new varieties of hybrid rice with disease resistance,high quality and high yield.Five new sterile lines(7021A、7023A、7033A、7035A、7037A)with high quality,disease resistance and high combining ability were used to test and match 121 hybrid rice combinations with several high quality restorer lines such as Yahui 2115,The agronomic traits,field resistance,rice quality and yield of these 121 combinations were tested.According to the ’ Sichuan Provincial Rice Variety Approval Standard ’,there were 75 combinations in the mid-late maturity combinations that met the approval criteria.Among them,7035A/CR6068、7035A/4086、7035A/NMP371、7035A/NMP372 、 7021A/line Zhenhe 、 7021A/Yuenongsimiao 、 7021A/R673 、7023A/4144 and 7023 A / Indica-Japonica Cross Material-1performed well,The appearance quality of these 9 advantageous combinations reached the first grade of high quality and the yield increased compared with the control varieties,which had great application prospects.