ABSTRACT

Two field experiments were carried out for two crop cycles at the high rainfall station of

International Institute for Tropical Agriculture (ilTA), Onne in southeastern Nigeria.

Experiment 1 was on the growth, yield and postharvest responses of selected plantain

genotypes to organic (poultry manure) and inorganic fertilizers. The experimental

design was a 3 x 4 factorial in a randomized complete block. There were 12 treatment

combinations consisting of three (3) fertilizer types (organic fertilizer, inorganic

fertilizer, no fertilizer) and four genotypes (PITA 14, 29525, Agbagba and 30456-3)

replicated three times. Experiment 2 was on the growth, yield and postharvest responses

of selected plantain genotypes to time of poultry manure application. The experimental

design was 2 x 5 factorial in a randomized complete block replicated three times. The

treatments were genotypes (PITA 17 and French Reversion) and time of poultry manure

application (application at planting, 1, 2, 3 months after planting (MAP), no

application). Data on growth, black sigatoka disease responses, yield and postharvest

fruit qualities were collected in both experiments. The result of experiment 1 showed

significant (P<O.O5) genotype and fertilizer effects on the different parameters. The

hybrid, 29525 produced highest yield and had longest fruit shelf life. Fruit edible

proportion, pulp dry matter content and degree of lightness were highest for Agbagba.

Highest pulp degree of yellowness was associated with PITA 14 whereas 30456-3 had

the poorest performance in most of the growth, yield and postharvest fruit qualities

except for leaf retention index where this genotype was highest with the application of

either organic or inorganic fertilizer. Therefore, 29525 was adjudged the best genotype

as it combined early maturity with high yield and longest fruit shelf life, especially

when it received poultry manure. Plants that received organic fertilizer flowered

earliest, produced tallest and thickest plants, largest economic yield, largest fruit edible

proportion and above-ground biomass. They also had highest tolerance to black

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sigatoka disease as well as longest fruit shelf life in the two crop cycles compared to the

other fertilizer treatments. However, pulp degree of yellowness reduced with the

application of organic fertilizer. The result of the second experiment showed that

'French Reversion' generally performed better than PiTA 17 with respect to most of the

parameters measured except for index of non-spotted leaves, harvest index, fruit degree

of yellowness and shelf life. The application of poultry manure at either planting, 1

MAP and 2 MAP respectively produced the highest growth, yield and best postharvest

fruit qualities in the plant and ratoon crops. Hence, the application of poultry manure

either at planting or 1 MAP was considered as the suitable time for the release of the

nutrients in the poultry manure as well as plantain's utilization for optimum growth and

development given a favourable environmental condition.