Xue Wenjiang (1938- ) is a native of Xuzhou, Jiangsu province. She graduated from Northwest Agricultural University in 1963. She is now a research fellow of Northwest Institute of Botany of China Academy of Sciences and council member of Seed Association of Shaanxi. She has taken on research on distant hybridization and breeding between wheat and Agropyron elongatum and genetic laws. She made significant contributions to the series of new wheat cultivars (Xiaoyan 4, 5, 6), among which Xiaoyan 6 has won National Invention Award, First Class in 1985. Since 1985, she had accelerated renewal of seeds of Xiao 6 by applying panicle selection method in order to purify the quality of Xiaoyan 6 and to make it more productive. She published several theses and co-authored All-Nation Varieties Records and Records of Wheat Varieties in Shaanxi.

NEW WHEAT VARIETY "XIAOYAN N0.6" BRED BY DISTANT HYBRIDIZATION

Li Zhensheng, Chen Shuyang and Xue Wenjiang

(Northwest Institute of Botany, Chinese Academy of Sciences)

Abstract

"Xiaoyan No.6" (former code name Ro) bred by distant hybridization between Triticum aestivum and Agropyron elongatum was released as a commercial variety by Crop Variety Examination and Approval Committee of Shaanxi Province in 1981.

"Xiaoyan No. 6" is a translocation line with winterness, early maturity and good quality, which is a semidwarf plant (90cm high) and resistant to lodging. It has more spikes than that of controlled variety in unit area due to its strong tillering ability. It is adapted to dry hot wind before harvest and fills rapidly at milking stage and shows golden color when matured. The wheat spikes are fusiform, long awned with white glume and white grain, thousand grain weight is 42g.The variety is resistant to stem rust, leaf rust and leaf blight, light affect scab and tolerance to stripe rust.

The breeding procedure of the hybrids between T. asstivum and Ag. elongatum is done in two steps. The first step is to establish new types ,that is : ((common wheat x Ag. elongatum) x common wheat) x common wheat. The three barriers: cross in compatibility, hybrids sterility and crazy segregation were overcome in this step. The second step is to breed new variety by crossing the new types with common wheat. Xiaoyan No.6is bred by crossing new type-Xiaoyan96 with common wheat variety-ST2422/464 following by lasser treatment at F4.

"Xiaoyan No.6" contains high protein (14.7-17.3%), which has proper fractions. Its wet gluten and sedimentation value are higher (40.6%, 58ml).The variety is superior for its excellent milling quality (flour extraction 66.8%, ash content 0.423%), better rheological stability of flour (5.9min), high quality value (58)and tensile strength (64cmg) as well as better baking quality, which has reached the level of standard strong flour quality. The variety has been grown in 10 provinces, such as Shaanxi, Henan, Shandong, Shanxi, Hebei, Anhui, and Jiangsu. Since 1980, the total growing areas of Xiaoyan No.6 have amounted to over 6.6 million ha., producing an additional yield of 2.5billon kg.