CORESTA Meeting, Agronomy/Phytopathology, Montreux,1997, AP55

Integrated nematode control on tobacco in South Africa: present status

BOTHA-GREEFF M.S.; VAN BILJON E.R.; DIPPENAAR M.C.; VORSTER T.B.
Tobacco and Cotton Research Institute, Rustenburg, South Africa
A strategy for nematode research with the objective of eventual integrated control of nematodes on tobacco has been implemented at TCRI. Long- and short-term research objectives for laboratory, greenhouse and field research have been identified and are currently being pursued. The most economically important nematodes of tobacco needing attention are different Meloidogyne species and races, followed by various Pratylenchus and Paratrichodorus spp. Chemical control remains the most important means of nematode control, to such an extend that chemicals are almost abused. Various new nematicides have been evaluated in field trials and some new products are being registered. Sources with genetic resistance to Meloidogyne spp. have been identified and successfully incorporated into tobacco breeding lines. To achieve this an intensive backcrossing programme is being followed to incorporate these genes into commercial tobacco lines with yield and quality characteristics being monitored closely. A biological control agent for nematodes is presently being evaluated for incorporation in an integrated pest management programme with adaptations to be made for improved nematode control on annual field crops with sub-optimum environmental conditions. Host plant suitability was determined for numerous rotational crops under greenhouse conditions. Long-term field trials are being done to determine the shift of nematode species and populations under different cropping regimes. Proper agronomical and field practices and water management strategies are advocated by extension and research officers in order to establish the basic principles and available control measures within an integrated nematode control system.