In order to enrich the germplasm resources of sugar beet resistant to damping-off and explore their physiological mechanisms in response to the disease,the previously isolated and purified Rhizoctonia solani were empl...In order to enrich the germplasm resources of sugar beet resistant to damping-off and explore their physiological mechanisms in response to the disease,the previously isolated and purified Rhizoctonia solani were employed to inoculate 112 main sugar beet varieties.The emergence rate,morbidity,mortality rate,peroxidase(POD)activity were investigated.The results showed that 112 main sugar beet varieties were divided into six levels according to the incidence rate:disease resistance(≤40%),high resistance(40%<to≤50%),medium resistance(50%<to≤60%),medium sensitivity(60%<to≤70%),high sensitivity(70%<to≤80%)and disease susceptibility(>80%).On the basis of this classification,5 disease resistant varieties,9 highly resistant varieties,9 moderately resistant varieties,20 moderately susceptible varieties,21 highly susceptible varieties,and 48 susceptible varieties were classified.Moreover,it was found that POD of disease-resistant varieties was significantly different from that of susceptible varieties.This approach provides a theoretical basis for the rational breeding of sugar beet varieties resistant to sugar beet damping-off,and have certain reference value for the development of the domestic sugar beet planting industry.展开更多
文摘In order to enrich the germplasm resources of sugar beet resistant to damping-off and explore their physiological mechanisms in response to the disease,the previously isolated and purified Rhizoctonia solani were employed to inoculate 112 main sugar beet varieties.The emergence rate,morbidity,mortality rate,peroxidase(POD)activity were investigated.The results showed that 112 main sugar beet varieties were divided into six levels according to the incidence rate:disease resistance(≤40%),high resistance(40%<to≤50%),medium resistance(50%<to≤60%),medium sensitivity(60%<to≤70%),high sensitivity(70%<to≤80%)and disease susceptibility(>80%).On the basis of this classification,5 disease resistant varieties,9 highly resistant varieties,9 moderately resistant varieties,20 moderately susceptible varieties,21 highly susceptible varieties,and 48 susceptible varieties were classified.Moreover,it was found that POD of disease-resistant varieties was significantly different from that of susceptible varieties.This approach provides a theoretical basis for the rational breeding of sugar beet varieties resistant to sugar beet damping-off,and have certain reference value for the development of the domestic sugar beet planting industry.