Characterisation of Phytophthora capsici causing foot rot of black pepper (Piper nigrum L.) in Julau, Sarawak

Abstract

Phytophthora foot rot disease remains a deadly disease of black pepper in Sarawak, a major pepper producing state in Malaysia. This study characterised three Phytophthora isolates, recovered from diseased plant tissues of foot rot infected pepper vines from two farms in Julau district, Sarawak. The three isolates were confirmed to be Phytophthora capsici based on the distinct torulose hyphae characteristic and molecular analysis. The isolates exhibited various colony and sporangia morphologies and growth rates. Two mating types were detected among the isolates based on the formation of oogonia in pairing tests between the isolates - one type associated with isolate I4 and I5 recovered from one farm and the second type with isolate E3 from the other farm. Virulence test indicated that I5 isolate was relatively more virulent than E3 isolate. This study provides important information to assist in the development of effective management strategies for the disease.

Keywords:

• Black pepper
• foot rot
• morphology
• Phytophthora capsici
• virulence

Acknowledgements

The authors would like to acknowledge the Faculty of Resource Science and Technology for providing laboratory facilities for the project activities.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This study was supported by the Universiti Malaysia Sarawak under grant F07/SpTDG/1765/2018.