Primi studi sul controllo genetico delle componenti di resistenza a Cercospora beticola in barbabietola da zucchero

[Autom. eng. transl.] Studies have been conducted on the genetic control of C. beticola resistance in sugar beet, considering the individual components of resistance rather than the variations in the severity of the disease. Resistant and sensitive beet parental lines and successive crossbreeding have been used, as well as cross-breeding with resistant parental. Some of these genetic materials had previously been characterized from the molecular point of view and the presence of 5 QTLs of resistance associated with four linkage groups (LG1, LG2, LG3 and LG9) had been highlighted. The resistance components taken into consideration were: efficiency of infection of conidia, duration of the incubation period, size of necrotic spots and production of spores on necrotic spots. The results of the tests carried out have shown that the two components of resistance of greatest interest are the efficiency of infection and sporulation, apparently controlled by different genes, with the former characterized by heritability inferior to the latter. The first of these components was related to the QTL present on LG1, the second to that on LG9 and, to a lesser extent, to the two QTLs closely associated with LG3, confirming the fact that these two components could be controlled by different genes. The duration of incubation was associated with QTLs on LG3 and LG9, albeit to a lesser extent than the previous ones, while for the size of necrotic spots no relation was found with the QTLs considered. These results open up the possibility of assisted selection to improve the level of resistance to C. beticola in sugar beet.