Analysis Of Different Genotype Tomatoes To Resistance Leaf Mildew And SSR Molecular Markers

As a massive outbreak of fungal diseases, tomato leaf mildew has sev erely restricted the tomato production in our country. Reseaching excellent disease-resistant varieties was still the main method for preventing the leaf mildew. This test used a different genotypes resistant and susceptible tomat os material and researched for photosynthetic characters, resistance physiolo gy, genetic and molecular markers law. A theoretical basis for resistance t o leaf mold in terms of the identification and screening of tomato breedingmaterial had provided. The study also played an important role in guidingto resistance tomato leaf mold breeding. Main research results are as folio ws.1. Between tomato strains 16 and strains61 had highly significantdiffere nces on the net photosynthetic rate, stomatal conductance and transpiration r ate before inoculation, 15 days after inoculation, two strains were significan t differences in the intercellular C〇2 concentration, the net photosynthetic ra te and transpiration rate terms. By leaf mold pathogen infection, it was thestrains 61 whose net photosynthetic rate, stomatal conductance and transpir ation rate declined, however the photosynthetic characteristics of strains 16 just got less variation.2. The susceptible strain 61 was significantly higher than disease-resist ant strain 16 in the both chlorophyll a and chlorophyll b before inoculation.Research from each strain and combination rangeability. Susceptible strains61 lower than the resistant strains 16 by leaf mildew infectionon in the accu mulation of chlorophyll.3. At the 5 days after inoculated;disease-resistantstrain 16 was significa ntly higher than the susceptible strain 61 at the G-POD activity aspect. An d at the time of 1 days, 10 days and 15 days, disease-resistant strain 16 w as higher than the susceptible strain 61 at the G-POD activity aspect. The disease-resistant strain 16 were always higher than the susceptible strains 61on the G-POD activity after inoculation.4. Through inoculating the tomato leaf mold pathogen, resistant tomato s5 susceptible tomatos and their offspring got field investigation in this expe riment. The two parental significant differences between resistant and suscep tible. The resistant tomatos and susceptible tomatos separated with 3 ! 1 rati o in F2 generation. Though a fit test,the tomato plants gene to resistant le af mold can be confirmed a single dominant gene.5. Using SSR molecular marker technology inspected 100 pairs of pri mers for PCR amplification. There are 73 pairs appear polymorphism. Rese aching at the anti-sense gene pool with rescreening. Only primer SSR23 ha d significant difference and it stabled at 210 bp in specific bands. So it ha d received a chain of leaf mildew resistance trait and tag.