CN-121986715-A - Method for cultivating heat-resistant broad-spectrum durable rice blast-resistant rice breeding material based on polygene polymerization

Abstract

The invention discloses a method for cultivating a heat-resistant broad-spectrum durable rice blast-resistant rice breeding material based on polygene polymerization. The invention selects the strong advantage indica-japonica hybrid indica rice restorer with strong heat resistance as a recurrent parent, uses the breeding intermediate material of the polymerization complementary broad-spectrum rice blast resistance genes Pigm and Pi-jx as a donor parent, and realizes the polymerization of the heat resistance and the broad-spectrum durable rice blast resistance genes Pigm and Pi-jx by combining molecular breeding with a conventional breeding method. Meanwhile, the breeding materials for resisting the heat-resistant broad-spectrum persistent rice blast are obtained by selecting representative strains to perform artificial inoculation identification of seedling blast and spike blast, natural induction identification of rice blast retransmission regions and heat resistance identification and combining main agronomic character evaluation in the whole growth period. The breeding material bred by the method has stronger heat resistance and broad-spectrum durable rice blast resistance, and accelerates the breeding process of heat-resistant and rice blast-resistant rice varieties.

Inventors

• LI YUHONG
• LIU JIANJU
• SHI WEI
• CHEN ZICHUN
• ZHU SHUHAO
• GAO PENG
• WANG ZHIPING
• YU LING
• XIAO NING
• LI AIHONG
• PAN CUNHONG
• HUANG NIANSHENG
• ZHANG XIAOXIANG
• JI HONGJUAN
• WU YUNYU
• CAI YUE

Assignees

• 江苏里下河地区农业科学研究所

Dates

Publication Date

20260508

Application Date

20251226

Claims (4)

1. 1. A method for cultivating heat-resistant broad-spectrum durable rice blast-resistant rice breeding materials based on polygene polymerization is characterized by comprising the following specific steps: (1) Selecting a breeding material which has excellent comprehensive agronomic characters and has been subjected to large-area production verification of heat resistance and high temperature resistance, but has poor rice blast resistance as a receptor parent, marking the parent as a parent P 1 , serving as a hybrid female parent and a recurrent parent, selecting a breeding intermediate material for polymerizing complementary rice blast resistance genes or a breeding intermediate material for polymerizing two rice blast resistance genes, marking the parent P 2 as a rice blast resistance gene donor parent and serving as a hybrid male parent, and obtaining F 1 after hybridization of the two rice blast resistance genes, wherein the complementary rice blast resistance genes or the two rice blast resistance genes are broad-spectrum rice blast resistance genes Pigm and broad-spectrum rice blast resistance genes Pi-jx; (2) Planting F 1 generation seeds, and backcrossing the flowering period and recurrent parent to obtain backcrossing 1 generation BC 1 F 1 population; (3) Planting BC 1 F 1 groups, wherein the planting scale is 100 plants, molecular detection is carried out in a seedling stage by utilizing a molecular marker InDel587 closely linked with a target resistance gene Pigm and a KASP molecular marker SN285 closely linked with a target resistance gene Pijx, a heterozygous single plant which contains two target resistance genes and has similar main agronomic characters and recurrent parents is selected, when the single plant is about to heading, heat resistance identification is carried out, standard reference DB 34/T3484-2019 is identified, and single plant cutting stubble regeneration with strong heat resistance or extremely strong single plant cutting stubble regeneration is selected and is backcrossed with recurrent parents in the flowering stage of the regenerated rice, so that BC 2 F 1 groups are obtained; (4) Repeating the step (3) until 4 generations of backcrossing are carried out, and obtaining BC 4 F 1 groups; (5) Planting BC 4 F 1 groups, respectively carrying out molecular detection on target resistance genes by using the linkage markers in the seedling stage, carrying out heat resistance identification in the heading stage, selecting single plant selfing seeds with homozygous resistance genes and strong heat resistance and similar main agronomic characters to recurrent parents to obtain a BC 4 F 2 strain; (6) Repeating the step (5) until 3 generations of selfing are carried out, and obtaining a BC 4 F 3 strain; (7) Planting BC 4 F 3 strain, respectively carrying out molecular detection and heat resistance identification on the target resistance gene by using the linkage markers at the seedling stage, obtaining the strain seeds with homozygous and strong resistance to the resistance gene by dividing the strain at the mature stage, and selecting the seeds with similar main agronomic characters to recurrent parents; (8) The method comprises the steps of planting BC 4 F 4 groups in a split line, expanding the planting scale to more than 500 plants, respectively carrying out target resistance gene molecule detection on single plants in the groups by using the linkage markers in the seedling stage, carrying out spike blast resistance identification on each plant by using a virulent single spore strain R in the booting stage, carrying out heat resistance identification on each plant in the heading stage, obtaining plant seeds of which the target genes are homozygous, the rice blast resistance is strong, the heat resistance is strong or extremely strong, and the agronomic characters are similar to those of recurrent parents in the mature stage, so as to obtain BC 4 F 5 ; (9) The strain BC 4 F 5 seeds are obtained, the seedling blight resistance, the spike blast resistance and the heat resistance are identified, the agronomic character evaluation is carried out in the mature period, the strain with strong or extremely strong heat resistance and main agronomic characters similar to recurrent parents is selected, and the breeding material BC 4 F 6 with heat resistance and rice blast resistance genes and broad spectrum and rice blast resistance is obtained; (10) The identification of the resistance and heat resistance of the heat-resistant broad-spectrum durable rice blast resistant breeding material BC 4 F 6 is carried out by inoculating and identifying the single bacterial strain of the resistance of the heat-resistant broad-spectrum durable rice blast resistant breeding material BC 4 F 6 with seedling blast and spike blast, simultaneously carrying out the identification of a multi-land rice blast disease nursery, comprehensively evaluating the comprehensive resistance of the breeding material and carrying out the heat resistance identification by referring to a reference standard DB 34/T3484-2019 by utilizing 7 representative bacterial strains which are collected and separated from different ecological areas and belong to A, B, C, D, E, F, G groups (identified varieties aiming at Chinese rice blast).
2. 2. (11) The heat-resistant broad-spectrum durable rice blast resistant breeding material BC 4 F 7 is used for verifying the rice blast resistance and heat resistance, 150 single cell strains are collected and separated in southern rice areas such as Sichuan, chongqing, hubei, jiangxi, anhui, hunan, guangdong, hainan, fujian, jiangsu and the like, single cell inoculation identification is carried out on the heat-resistant broad-spectrum durable rice blast resistant breeding material BC 4 F 7 and recurrent parents by an injection method in a seedling stage room and a booting stage, meanwhile, natural induction identification is carried out in rice blast retransmission areas such as Hubei Enshi, jiangxi Jinggan, fujian Hangzhong and Anhui, and the like, in addition, 30 single cell strains are selected from a rice blast fungus library collected and stored for a plurality of years, the single cell inoculation identification is carried out in a booting stage by an injection method, and the heat resistance identification is carried out in the same period by using a manual climate chamber identification and production practice high-temperature verification breeding material with reference standard DB 34/T3484-2019.
3. 3. The method according to claim 1, wherein the breeding material which has excellent comprehensive agronomic characteristics and has been verified to be heat-resistant and high-temperature-resistant by large-area production, but has poor rice blast resistance is a strong dominant indica-japonica hybrid indica rice restorer line MR89, and the breeding intermediate material for the polymerization complement rice blast resistance gene is YD6-Pigm/Pi-jx.
4. 4. The method for cultivating the heat-resistant broad-spectrum durable rice blast-resistant rice breeding material based on polygenic polymerization according to claim 1 is characterized in that in the step (9) and the step (11), indoor inoculation is carried out in a seedling stage to identify the seedling blast resistance, field planting is carried out, mixed inoculation is carried out in a booting stage to identify the spike blast resistance through an injection method, comprehensive identification of the rice blast resistance is carried out in a multi-field nursery in a whole breeding stage, heat resistance identification is carried out in a heading stage, and heat resistance and rice blast resistance of the cultivated heat-resistant broad-spectrum durable rice blast-resistant breeding material MR89-Pigm/Pi-jx are comprehensively evaluated.

Description

Method for cultivating heat-resistant broad-spectrum durable rice blast-resistant rice breeding material based on polygene polymerization Technical Field The invention belongs to the technical field of rice molecular breeding, and relates to a method for cultivating a heat-resistant broad-spectrum durable rice blast-resistant rice breeding material based on polygene polymerization. Background Rice is one of the major food crops for humans. Global warming exacerbates the impact of abiotic stress (high temperature, drought, etc.) and biotic stress (rice blast, bacterial leaf blight, etc.) on crop yield. In recent years, with the frequent occurrence of abnormal climate, high temperature heat injury and rice blast epidemic are caused, large-area yield reduction of rice production is caused, and the major hidden danger of grain safety is caused. However, the conventional breeding period is too long, so that the high temperature resistance and the rice blast resistance are difficult to synergistically improve, the cultivation of the target breeding material meeting the production needs is limited, and therefore, the cultivation of the heat-resistant broad-spectrum rice blast resistant breeding material is rapidly required to be accelerated by utilizing various breeding technical means, and the damage of high temperature and rice blast to the rice production is restrained. High temperature heat injury has become a core environmental stress factor for restricting high and stable rice yield. In recent years, as global climate warming increases, extremely high temperature events frequently occur, and the influence of the extremely high temperature events on rice production is expanded from single yield reduction to multi-dimensional crisis such as quality reduction and regional adaptability challenges. Therefore, there is an urgent need to screen heat-resistant germplasm resources, in particular germplasm resources with excellent comprehensive properties, which can be directly bred and utilized, and cultivate heat-resistant rice varieties by utilizing the heat-resistant characteristics of the germplasm resources, thereby reducing the influence of extremely high temperature on rice production. Rice blast caused by rice blast bacteria (Magnaporthe oryzae) is one of the most main fungus diseases threatening the safe production of rice, and the yield of rice caused by rice blast is reduced by 10% -30% each year worldwide (Skamnioti and Gurr 2009). In recent 40 years, rice blast has become a major problem in rice production due to the narrowing of the parental genetic base and the diversity of highly pathogenic rice blast bacteria (Liu et al 2010), and has brought about a great potential hazard to safe production of rice (Wu et al 2016). The molecular Marker Assisted Selection (MAS) technology is utilized to polymerize different broad-spectrum and durable rice blast resistance genes, and the novel rice variety with broad-spectrum and durable rice blast resistance is cultivated, so that the method is the most economic and effective measure for controlling rice blast, and can realize the durability of the rice variety against rice blast. The broad-spectrum rice blast resistance gene Pigm has been proved to have wide resistance spectrum and strong resistance (Deng et al, 2006), has better resistance effect of seedling blight and spike blight (Wu et al, 2016), and has proved application value in basic research and production practice, but in practical production application, the disease resistant variety cultivated by single resistance gene tends to rapidly lose resistance in a short time of application and become a disease resistant variety due to the fact that the physiological quantity of rice blast is too small, pathogenicity differentiation and variation are frequent, and the resistance of Pigm also tends to gradually decline after years of production and application. Pi-jx is a recently newly discovered broad-spectrum rice blast resistance gene, has good disease resistance to 155 pathogens collected from 8 provinces of Jiangsu, anhui, hubei, hunan, henan, zhejiang, guangdong, shandong and the like, and most importantly has good disease resistance to a strong pathogenic rice blast strain R5-1 with Pigm broad-spectrum resistance gene pathogenicity (separated from the mountain areas of Wuling, which are recurrent throughout the year of rice blast, and has a pathogenicity rate of over 95 percent for materials with different genotypes, which is obviously higher than that of a large-area production of the separated common rice blast strain). Resistance to Pi-jx has been shown to have a complementary effect to Pigm that can compensate for the loss of Pigm resistance. Therefore, the molecular marker assisted selection technology is used for polymerizing the rice blast resistance genes Pigm and Pi-jx, so that a novel gene combination mode is provided for cultivating a broad-spectrum durable rice blast resistance variety, a wider