Potential existence of multiple Tylenchulus semipenetrans biotypes in South Africa
2015
Mathabatha, R.V. | Mashela, P.W. | Mokgalong, N.M. | Dube, Z.P.
The existence of multiple Tylenchulus semipenetrans biotypes within a citrus-producing region complicates the selection of nematode-resistant rootstocks for managing the slow decline of citrus. The potential existence of multiple T. semipenetrans biotypes in South Africa was investigated under greenhouse conditions on differential host plants using nematode isolates from 18 citrus-producing districts with at least six diverse soil groups and three different climates. After three nematode generations, the regional effects had no influence on final nematode population densities, whereas the differential host plants significantly segregated the nematode reproductive potentials. On Olea europaea reproductive potentials (eggs and juveniles/g) were zero, whereas those on Citrus jambhiri and Poncirus trifoliata ranged from 79 to 482 and 86 to 433, respectively. All T. semipenetrans isolates, regardless of the soil group and climate type, behaved similarly to the Poncirus biotype, which therefore rules out the existence of multiple T. semipenetrans biotypes in South Africa.
显示更多 [+] 显示较少 [-]