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Peroxidase (PO) Polyphenoloxidase (PPO) and Phenylalanine ammonia-lyase (PAL) activities in stem extracts of six cacao clones (IMC 67, ICS 1, TSH 1188. P 18, SCA 6 and TSH 1076) were measured spectrophotometrically in (i) healthy tissues; (ii) tissues wounded with a 3-mm diameter cork borer and (iii) tissues inoculated with the canker pathogen Phytophtkora patmivora. The results indicated significantly high {P < 0.05) activities ofthe three enzymes in extracts obtained from inoculated and wounded as opposed to those from healthy tissues. The activities of these enzymes were significantly higher in the extracts of IMC 67, low in TSH 1076. SCA 6 and P 18 and intermediate in TSH 1188 and ICS 1. There was no significant difference in enzyme activities among the genotypes TSH 1076. SCA 6 and P 18 and also between ICS 1 and TSH 1188 Starch gel electrophoresis of PO indicated differences in banding pattern/band-intensity amongst IMC 67, ICS 1 and SCA 6 and also between inoculated and uninoculated stems. These results are discussed in relation to lignin and phenol metabolism associated with plant resistance to pathogen attack.

Due to the overwhelming enthusiasm about the meetings, participants suggested setting up a communication network for researchers and professionals, and an organizational framework for a biannual conference. Interested persons should send their addresses, disciplines, and research areas to me care of School of Architecture and Urban Design, University of Kansas, Lawrence, KS 66045. David C. Saile, University of Kansas.D

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An assessment of canker incidence in six cocoa clones revealed IMC 67 to be least susceptible and TSH 1076 most susceptible among the clones tested (ICS 1, IMC 67, P 18, SCA 6, TSH 1076 and TSH 1188). These results were confirmed by greenhouse studies on budded plants using artificial inoculation. IMC 67 with the smallest canker lesion size was found to have the highest value (3.75 N/m2) for extra‐xylary tissue hardness while TSH 1076 with the largest lesion size had the lowest value (1.9 N/m2). Bark moisture content determination also showed lowest values for IMC 67 and highest for TSH 1076. Bark hardness and moisture content were highly correlated with canker resistance.