Long-term control of Phytophthora diseases of cocoa using trunk-injected phosphonate
Guest, D.I., Anderson, R.D., Foard, H.J., Phillips, D., Worboys, S., and Middleton, R.M. (1994) Long-term control of Phytophthora diseases of cocoa using trunk-injected phosphonate. Plant Pathology, 43 (3). pp. 479-492.
PDF (Published Version)
- Published Version
Restricted to Repository staff only
Pod rot and stem canker, caused by Phytophthora palmivora, are serious diseases of cocoa causing pod losses of up to 63% and the death of up to 10% of trees annually on Kar Kar Island, Papua New Guinea. Trials were conducted on commercial cocoa plantations to compare the effectiveness of potassium phosphonate when applied as trunk injections, trunk paints and foliar sprays, and trunk injections of Aliette CA and of Ridomil 250EC, with conventional Ridomil-based spray programmes. The results show that, in trials conducted over 5 years, injections of potassium phosphonate give the highest healthy pod yield and lowest incidence of Phytophthora pod rot and stem canker when compared with Ridomil-based spray programmes or trunk injections of Ridomil 250EC or Aliette CA. The increase in ripe healthy pod yields was due to both pod rot and stem canker control. The level of control is independent of the seasonal timing of injection. Optimum control was achieved with annual injections of 15 g a. i. per tree, and varied with tree size and disease severity. Injections of phosphonate will, under the range of conditions found in our trials, provide the most cost-effective control of Phytophthora diseases.
|Item Type:||Article (Refereed Research - C1)|
|Funders:||Cocoa Blackpod Research Trust|
|Date Deposited:||27 Sep 2011 01:43|
|FoR Codes:||07 AGRICULTURAL AND VETERINARY SCIENCES > 0706 Horticultural Production > 070603 Horticultural Crop Protection (Pests, Diseases and Weeds) @ 100%|
|SEO Codes:||82 PLANT PRODUCTION AND PLANT PRIMARY PRODUCTS > 8202 Horticultural Crops > 820299 Horticultural Crops not elsewhere classified @ 100%|