Innovation And Application Of Rice Germplasm Resources Through Pollen Tube Pathway

At present, the large-scale application of few fine rice varieties has led to the genetic basis of rice breeding material becomes more and more narrow. It becomes difficult to increase production and quality further, therefore the key point lies in innovation of germplasm. Distant hybridization is a way to expand the germplasm. which often face the problems of hybrid incompatibility or highly infertility. While pollen tube pathway does not meet those problems. It can aslo avoid the security problems caused by selection marker gene and vector such as particle bombardment and Agrobacterium-mediated. It is simple, low cost, less demanding on the experimental conditions, and it has a good value in application.In this experiment, whole genome DNA of grassy mountain Fargesia is imported to rice (En3B,9311. Huazhan, Q7xuan. Yanhui22, Enhui142) through pollen tube pathway. Variations different from receptor plants (CK) are screened by phenotypic identification and stabilize those variations through self-crossing for 3-4 generations. Then identify the genetic background differences between transformed plants and receptor plants (CK) by using 49 pairs of SSR markers (including some 24 pairs of SSR primers are used to construct a standard DNA fingerprint in rice). Select some good transgenic plants and receptor plant (CK) and hybridize with three male sterile lines (6303S,3S.03A).Infer their values in last. The main research results are as follows.(1)36 rice lines, can inherit stablely and are different from the receptor plants, are created by pollen tube pathway.(2)The conversion rate of 6 receptor plants ranges from 1.23% to 4.95%. the average rate is 3.11%.(3)New lines and primary receptor species are made genetic background analysis by using 49 pairs of SSR primers, it find that there are 2-30 pairs of primers between raw materials and transformed plants. The genetic similarity coefficient of En3B and transgenic plants is 0.55.9311 is 0.72-0.97. Huazhan is 0.92-0.97. Q7xuan is 0.94-0.97. Yanhui22 is 0.72-0.97. Enhuil42 is 0.60-0.98. This illustrates that there are differences in genetic background between transformed plants and receptor plant and among transformed plants.(4)Transgenic plants and receptor plant (CK) hybridize with male sterile lines in the same time. We find that there are big differences by analyzing F1 traits. Compared with the theoretical yield of sterile line x receptor plants and Fengliangyou No.4. we find that the combination of T17-the transgenic plant of Yanhui22 and T33-the transgenic plant of Enhuil42 with 6303S have reached a significant or very significant level, and they might form a new species.The above results show that this method can produce mutation by transforming distant genomes in rice, and is feasible in terms of the creation of new germplasm. And integration of exogenous genomic fragment is random. It can produce different variations. Hybridizing with CMS lines shows that yield of some germplasms is over the recipient parent, and it provides possibility of creating excellent combinations. This method has great practical value in production practice. It can also provide a good foundation material for genetic studies by creating a new germplasm.