WALKER et al. (op cit, 1983) divided the farms which they visited into four categories and these, which follow below, were used as the starting point for field survey.

Category A - Tall, healthy plants with large bunches throughout. Complete cover. No falldowns. No nematode root necrosis and no weevil corm damage.
Category B - Generally healthy plants with large bunches. Occasional stunted plants with small bunches, with or without falldowns (< 10%) associated with nematode root necrosis and/or weevil damage.
Category C - Reasonable plant growth but with small or moderate bunches. Stunting slight or obvious and yield in noticeable decline. Poor cover. Falldowns common (10-15%) associated with moderate to severe nematode root necrosis (> 25%) and/or serious weevil corm damage. No other major constraints to production.
Category D - Bananas in serious decline to the point of non-productivity. Plants generally very stunted, often chlorotic, small or no bunches, very weak or non-existent followers. Very poor cover. Falldowns common (> 10%) or very common (> 50%) associated with very severe nematode root necrosis (> 75%) and/or weevil corm damage. Often occurring in areas of poor soil fertility.

The first stage of the present project, therefore, was the making of an extensive series of visit to the many areas of the Region where bananas are grown. The exercise undertaken was to visually examine a number of shambas in each of the areas, so as to gain a picture of the incidence of weevils and nematodes and of the general state of health of the plants. Harvested plants were dug up and the stems and corms split open to look for the presence of weevil adults or juveniles, or their feeding tunnels. Root samples from immature, mature and harvested plants were split longitudinally and examined for the characteristic discolouration and necrosis of the cortex which endo-parasitic nematodes cause. The local extension workers were involved both as guides and in order to learn of their perceptions of the problems. They were asked to take the researchers both to the shambas of "progressive", or good, farmers and to shambas where the bananas were not in a satisfactory condition.

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