Preliminary Location And Molecular Marker Screening Of Powdery Mildew-resistant Gene In Bitter Gourd (Momordica Charantia L.)

Bitter gourd(Momordica charantia L.), a cucurbitaceous and momordica plant, is widely grown and well enjoyed because of its plentiful nutrition facts and general utilization as both vegetable and China medicine, but bitter gourd easily suffered from powdery mildew during its production, which causing its quality and yield to decrease. To completely and safely solve the damage of powdery mildew to bitter gourd, in this study, near-isogenic DNA gene pools of bitter gourd strongly resistant to and severely sensitive to powdery mildew were constructed after powdery mildew-strongly resistant MC18of wild bitter gourd crossed with powdery mildew-severely susceptible MC1-2of bitter gourd cultivar to form F2segregate population and disease-resistant ability of plants in F2population was identified. Molecular markers linked to genes resistant to P. xanthii race1were screen by SRAP and SCAR techniques. At the same time, powdery mildew-resistant genes of bitter gourd were located to map after constructing molecular linked map of bitter gourd. The research results are summarized as follows:(1) After construction of the related generational population through strongly powdery mildew-susceptible MC1-2of bitter gourd crossing with seriously powdery mildew-resistant MC18and the analysis of ability of resistance to P. xanthii race1for bitter gourd plants in each generational population, this resistant ability was controlled by a pairs of recessive genes.(2) The optimum SRAP-PCR system (20μL:DNA5ng/Ml, dNTPs0.05mmol/L, Mg2+2.5mmol/L, primer0.6μmol/L, Taq DNA polymerase0.088U/μL) could isolated differential fragments in DNA near-isogenic gene pool from F2segregate population of bitter gourd with the help of the known SRAP-PCR amplified procedure, and be suitable to screen SRAP molecular markers linked to powdery mildew-resistant genes of bitter gourd.(3) One hundred and twenty one pairs of SRAP primers were selected from1188pairs of SRAP primers with maternal and paternal parent DNA in NO.1round, and11from121with biparental DNA and DNA near-isogenic gene pool in No.2, which contributed to screen powdery mildew-resistant molecular markers from DNA near-isogenic gene pool.(4) Five of molecular markers of bitter gourd gene resistant to P. xanthii race1were obtained, and one of five SRAP molecular markers was successfully changed to practical SCAR molecular marker.(5) A sheet of molecular genetic and linked map of bitter gourd was gotten, and gene resistant to P. xanthii race1was premilinarily located to the aforementioned map.