Investigations on a seedling die-back of Theobroma cacao L. in Nigeria, 1: Description of the disease and its spread in the nursey

The symptoms of a seedling die-back disease of cacao are described. Difficulty in obtaining pure culture of the causal agent [Phytophthora sp. near P. palmivora (Butl.) Butl.] from infected plants was overcome by inoculating cacao pods and egg-plant fruits with portions of infected stems. Inoculation experiments confirmed the observation that only young seedlings, less than eight weeks old, are susceptible to infection. Humid conditions are apparently a pre-disposing factor for the disease. The disease appears in the first instance to occur at random in the nursery but subsequent spread is apparently from infected to adjacent plants.