Stability analysis of incidence of tomato spotted wilt in Virginia-type peanut cultivars and breeding lines.

摘要

Tomato spotted wilt (TSW) caused by Tomato spotted wilt tospovirus (TSWV) has become a serious constraint to peanut (Arachis hypogaea L.) production in the Virginia-Carolina production area. Regression stability analysis was applied to TSW incidence data collected in 64 trials conducted over 17 years to determine if an array of 31 virginia-type cultivars and breeding lines exhibited variation in their reactions to increasing levels of general TSW intensity compared with the standard field-resistant cultivar Georgia Green and hirsuta-type line PI 576636. Eight cultivars (NC 7, NC 9, NC 10C, NC-V 11, NC 12C, Perry, Phillips, and Brantley) had mean effects greater than zero (P<0.01) while Bailey, four Bailey siblings, and N96076L, Bailey's resistant parent, all had mean effects less than zero (P<0.01). The deviations of the slope of regression on environmental index ( beta _k) for four of the eight susceptible cultivars were greater than zero, indicating greater than average reaction to increased levels of TSW. The beta _k for Bailey indicated that its response to increasing levels of TSW was flat. PI 576636 was confirmed as a highly field-resistant line. The slopes of Georgia Green, the standard TSWV-resistant runner-type cultivar, the Bailey siblings and N96076L did not differ from the average of all lines. The correlation between mean effect and beta _k was r=0.693, indicating that approximately half the variation in beta _k could be explained by mean effects. However, the regression analysis provided information useful in describing the TSW reactions of the lines and cultivars.