Prof Noelani van den Berg

I am the research leader for the Fruit Tree Biotechnology Programme (FTBP). The avocado research project is a joint venture between FABI and The Hans Merensky Foundation. The aim of this project will be to shed light and understand the mechanisms and gene expression pathways whereby tolerant avocado rootstocks, are protected against Phytophthora cinnamomi. My education is in the fields of Plant Pathology and Botany and my research experience is in molecular plant-micobe interactions with a special interest in the identification and isolation of defence-related genes.

The research that I performed during my Ph.D. was the first attempt at isolating defence-related genes in a tolerant banana in response to Fusarium wilt. Panama disease (FusariumWilt) of banana is recognized as one of the most devastating diseases in the recorded history of agriculture. Management strategies for the disease currently rely on host resistance and cultural practices. Several banana cultivars and landraces have tolerance/resistance to the pathogen, Fusarium oxysporum f.sp. cubensesubtropical race 4. However, these plants are not always suitable for production in South Africa. This project was the first of its kind in this field and molecular techniques such as Suppression Subtraction Hybridization (SSH), Micro-array technology, Quantitative Reverse Transcriptase PCR provided us with tools to identify the genes responsible for resistance/tolerance in this tolerant Cavendish selection or any other germplasm source with resistance to the pathogen. The gene identification can be applied in three ways - firstly, candidate genes can be used as markers for resistance traits in a banana improvement program; secondly, the information lead to a better understanding of the mechanisms whereby resistance is conferred, thereby providing new defence strategies; and thirdly, the genes will be used in banana.