Grade：The second prize
Winners：Chen Peidu, Wang Xiu’e, Liu Dajun, Huang Huiyue, Cao Aizhong, and Guo Jinkao.
Collaborators：Nanjing Agricultural University, Neijiang Institute of Agricultural Sciences, Shijiazhuang Institute of Agricultural and Forestry Sciences.
The narrowed genetic basis of crop variety is one of the major bottle-necks in modern crop breeding. Wild relatives of cultivated crops have many useful traits, and are considered as beneficial resources for broaden the genetic basis. The identification, introduction and utilization of alien genes is very important, and this can be achieved by the development of alien chromosome lines, especially alien translocations or introgressions. However, due to the genetic distance of wild relatives with common wheat, the induction of such translocation and introgression has been difficult and low efficient, not to say the cloning of the alien target genes. In this program, supported by the National “863” Project and the National Natural Science Foundation, our research team has made over 30 years efforts to introduce genes related to disease resistance, abiotic stress tolerance and grain quality from Haynaldia villosainto wheat via wide hybridization, chromosome engineering and molecular genetics techniques. Following a step by step technical route, we induced “whole alien genome→complete alien chromosome→a chromosomal arm→small chromosomalfragment→a single target gene” into common wheat by the development of wheat-H. villosa amphiploid, alien addition/substitution lines, whole arm translocation lines, small fragment translocation/introgression lines and transgenic wheat. The translocation line T6VS/6AL containing powdery mildew resistance gene Pm21 from H. villosa and strip rust resistance gene Yr26 was developed and has become one of the most important resistance sources in wheat breeding for powdery mildew and stripe rust resistances. Using T6VS/6AL as parent, a series of wheat varieties have been developed and released. Themain innovations in the present research program are as follows:
(1)Proposeda high throughput chromosomal structural change induction and whole genome translocation creation technique by amphiploid pollen irradiation; Proposed a target chromosome small fragment translocation or introgression induction technique by female gamete irradiationof a whole arm translocation carrying the target gene. Highly efficient induction ofintergeneric chromosomal translocation can be achieved by 60Co-γ irradiation of the amphiploid pollens and pollinated to normal common wheat, followed by FISH and marker analysis of the M0, then backcrossing with wheat variety. Target chromosome small fragment translocation or introgression can be achieved by mature female gametes 60Co-γ irradiation of the T6VS/6AL and fertilized by the pollens from normal wheat variety, followed by FISH and molecular marker analysis of the M0 and then backcrossing with normal wheat variety. The efficiency of genome-wide chromosome translocation and the frequency of target small fragment intercalary translocation are significantly improved.
(2)Proposed an approach for cloning of the target gene from wild species. Taking the advantage of the various types of alien translocation lines developed in this research program, we proposed an efficient approach for cloning the alien gene in wheat background. By integrating techniques of molecular cytogenetic method, molecular genetics including Microarray and comparative genetics, we cloned the key member of Pm21, providing a successful example of alien gene cloning.
(3)Created a series of new germplasms carrying elite traits. The wheat-H. villosa T6VS/6AL translocation lines with resistances to both powdery mildewand stripe rust were released to wheat breeders. Using them as resistance parents, 18 wheat varieties were developed and commercially applicated in an acreage of about 62.23 million Mu (4.135 million ha). The total yield increase was about 1.682 billion kg, which was equivalent to an increased farmer-gate income of 3.92 billion RMB. In addition, a number of elite wheat lines using the translocation lines and their derivatives as parentsare being tested indifferent wheat grown areasand will make significant contribution to wheat production in China.
In this research, 3 invention patents and 5 new plant variety IPs were authorized.46 papers including 16 SCI publications in peer-reviewed international journals such as PNAS, TAG, etc. were published. The achievements of this research program were evaluated by an evaluation committee consisted of world famous experts in wheat genetics and breeding areas, they concluded that this research, especially those in the exploitation and utilization of useful genes from H. villosa, are ranked as the top research in the world; Prof. Bikram Gill, a world famous scientist from Kansas State University, USA, was invited to write a complementary in the same issue of PNAS, in which we published the research of Pm21 gene cloning. He indicated that the T6VS/6AL translocation line is the second whole arm translocation line after the T1RS/1BL translocation line, which has made great contribution to wheat improvement. He also indicated that this research, by creatively integrated cytogenetics and molecular biology, has successfully solved the problems of precise location and cloning genesfrom wild species and set an example of exogenous gene cloning; Prof. He Zhonghu, a famous Chinese scientist in wheat genetics and breeding, published a paper “The Progress in Wheat Breeding in China” in the Journal of Crop Science, in which he indicated that the translocation line T6VS/6AL is resistant against powdery mildew and stripe rust andalso has good agronomic traits, the development of T6VS/6AL is one of the most remarkable progresses in wheat research in the past decade and hasplayed an important role in wheat breeding in China.
This program was also awarded “First prize award for technological invention” and “First prize award for science and technology progress” by the Ministry of Education.