Effect of PVY [potato virus Y] primary infection on potato clones with different levels of resistance
1989
Hoa, V.D. | Rasco, E.T. | Vander Zaag, P. (Agricultural Univ. Hanoi (Viet Nam))
A study to examine the effect of potato virus Y (PVY) primary infection on tuber yield was conducted using five potato clones with different levels of resistance under lowland field conditions in the Philippines. The loss in tuber yield was a function of varietal resistance/tolerance, disease severity, and length of time from infection. Clones with either hypersentivity (Serrana, Conchita) or extreme resistance (LT-8) showed no reduction in tuber yield. On the contrary, tuber yield was adversely affected in the susceptible clone, LT-7. The clone B71-240.2 appeared to be susceptible to PVY but had no significant yield loss. For LT-7, the earlier the infection occurred the more severe were the symptoms and consequently the higher was the loss in tuber yield. The relationship between loss in tuber yield and disease severity was linear. Based on path coefficient analysis, the virus-induced loss in tuber yield was primarily due to reduction in number of tubers and to a lesser extent due to smaller tuber size. In comparison with healthy plants, the compensatory effect between these two tuber yield components was reduced in infected plants.
显示更多 [+] 显示较少 [-]