Login | Create Account (DAF staff only)

Genetic diversity, aggressiveness and metalaxyl sensitivity of Pythium aphanidermatum populations infecting cucumber in Oman

Al-Sa'di, A.M. and Drenth, A. and Deadman, M.L. and Aitken, E.A.B. (2008) Genetic diversity, aggressiveness and metalaxyl sensitivity of Pythium aphanidermatum populations infecting cucumber in Oman. Plant Pathology, 57 (1). pp. 45-56.

Full text not currently attached. Access may be available via the Publisher's website or OpenAccess link.

Article Link(s): http://dx.doi.org/10.1111/j.1365-3059.2007.01700.x

Publisher URL: http://www3.interscience.wiley.com/cgi-bin/home

Abstract

Seventy three isolates of Pythium aphanidermatum obtained from cucumber from four different regions of Oman and 16 isolates of muskmelon from the Batinah region in Oman were characterized for aggressiveness, sensitivity to metalaxyl and genetic diversity using AFLP fingerprinting. Twenty isolates of P. aphanidermatum from diverse hosts from different countries were also included in the study. Most isolates from Oman were found to be aggressive on cucumber seedlings and all were highly sensitive to metalaxyl (EC50 < 0•80 µg mL−1). Isolates from cucumber and muskmelon were as aggressive as each other on both hosts (P > 0.05), which implies a lack of host specialization in P. aphanidermatum on these two hosts in Oman. AFLP analysis of all isolates using four primer-pair combinations resolved 152 bands, of which 61 (~40%) were polymorphic. Isolates of P. aphanidermatum from Oman and other countries exhibited high genetic similarity (mean = 94.1%) and produced 59 different AFLP profiles. Analysis of molecular variance indicated that most AFLP variation among populations of P. aphanidermatum in Oman was associated with geographical regions (FST = 0.118; P < 0.0001), not hosts (FST = -0.004; P = 0.4323). These data were supported by the high rate of recovery (24%) of identical phenotypes between cucumber and muskmelon fields in the same region as compared to the low recovery (10%) across regions in Oman, which suggests more frequent movement of Pythium inoculum among muskmelon and cucumber fields in the same region compared to movement across geographically separated regions. However, recovering clones among regions and different countries may imply circulation of Pythium inoculum via common sources in Oman and also intercontinental spread of isolates.

Item Type:Article
Additional Information:© The Authors. © British Society for Plant Pathology.
Keywords:AFLP; AMOVA; damping-off; genetic differentiation; genetic similarity; phenotypes.
Subjects:Science > Botany > Cryptogams
Plant pests and diseases > Individual or types of plants or trees
Plant culture > Vegetables
Science > Biology > Genetics
Plant pests and diseases > Pest control and treatment of diseases. Plant protection > Pesticides
Deposited On:17 Nov 2008 06:24
Last Modified:10 Jun 2011 01:43

Repository Staff Only: item control page