| Banded leaf and sheath blight (BLSB) is one of the most harmful diseases with a globally harmfulness. Especially, with the changing of plant methods for high yield, for examples, used more nitrogen fertilizer , planted more long green period of maize varieties, the serious harmfulness of BLSB has been conducted to continue harm in both spread and worldwide in maize more and more. It is also serious diseases in China especially in the southwest mountain areas of China. The studies on BLSB were recorded mainly in symptom pathogeny and epiphytotic development of it. Since the lack of a comprehensive understanding of BLSB resistance sources, there are few works on breeding for resistance to this disease untill now. That's the reason why the germplasm is insufficient for resistance to the disease. For improving maize BLSB breeding by thorough investigating of the biodiversity of BLSB resistance germplasm, a systematic researching on the resistant to the disease have been completed, including traditional quantitative analysis -character genetic analyzing methods such as genetic effect analyzing method and the modern molecular locating method such as QTLs'. The main results obtained as follow:1 , 203 inbred lines were evaluated the resistance to BLSB by artificial inoculation method in many years and different locations. 22 inbred lines among them were detected from 1997 to 2000 , 45 inbred lines from 2000 to 2001, 134 inbred lines in one year. According to the identification of resistant for BLSB, the maize inbred line CML270 with higher resistance for maize BLSB has been found. Comparing with other inbred lines, CML270 is highly and stably resistant material. The disease index of CML270 was 8.4259.1~13.9% which was lower than the CK of inbred line 478 (the disease index was 36-91.4%). The relative resistant index of CML270 was 87%, which was higher 75.6% than 478's. The inbred lines R15,R09,CML163,Fla2Bt-116 and LI037 were middle degree for resistance to BLSB.2, The inbred line CML270 is highly resistant for maize BLSB pathogen AG-1-1A that five stubs adopt from Hunan, Jiangsu, Henan, Hainan Sichuan respectively. The disease indexes were 11.1 %, 12.5%, 12.7%, 10.0%, 10.0% by artificial inoculation method. The disease index of this line was 13% under natural identification, which was stably. But other inbred lines disease indexes were different by artificial inoculation of different stubs. According to the results of many years in different location, CML270 resistant to BLSB is a quantitative heredity trait, and it's maybe level resistance material.3, The degrees of BLSB disease of F2, BC1, BC2 generations derived from the combination of CML270 (highly resistant) and 478 (highly susceptible) were continuous distributing with single apex. The average of disease degree were: 1.97(F2-1),1.91(F2-2),1.88(BCl-1),2.08(BCl-2), respectively. The Additive-dominant genetic model was found to be functional to induction efficiency. The value of [d] accounted for the main existence. According to the traditional quantitative-character genetic analyzing method, the resistant to BLSB was controlled by 4~7 mini-poly-genes.4, The genetic linkage map be constructed with 125 SSR markers based on maize population consisting of 328 BCF2:3 plant lines, which covered 1939 cM of maize genome. The average mapping distance was about 15.5 cM, and the maximum distance was 47.5 cM.5, For the three characters of the resistance to BLSB, QTLs mapping analysis were done by Interval Mapping(IM)and Composite Interval Mapping (IM).Four QTLs of the relative resistant index trait had been located at the first and seventh chromosomes by IM. Three QTLs of the relative disease high had also been located at the first and seventh chromosomes by EM. Three QTLs of absolute disease dot height at the first, forth, seventh chromosomes. Four QTLs of the relative resistant index trait had been located at the first and seventh chromosomes by CIM too. Three QTLs had been located at the forth, seventh and eigh...
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