Bananas and Food Security - Bioversity International

384 Les productions bananières / Bananas and food security – Session 2
plantains had the longest ripening period and the lowest respiration rate compared with
the landrace plantains and cooking bananas. However, hybrid plantains were less
resistant to harvesting and loading stresses, unlike cooking bananas which had the
highest resistance to these stresses. Cooking bananas had the shortest number of days
(1.5) between stage 4 (50% green: 50% yellow) and stage 7 (100% yellow) of ripening,
while plantain hybrids had the longest (4.5 days). The longer ripening period of hybrid
plantains is an advantage with respect to storage and processing. Cooking bananas, due
to their firmness will fit well into the prevailing fresh fruit distribution system in Nigeria,
while the weaker texture of the hybrids calls for breeder’s attention.
Introduction
Plantain and banana (Musa spp.) are an integral part of the humid tropical farming
system. It is thought that these crops were some of the first to be domesticated, as they
require no specialised tools for harvest or propagation. The many forms in which they
are consumed also indicate the long association between man and these crops. Musa
fruit are probably the only fruit that can be consumed in the unripe, ripe and over-ripe
stages. In sub-Saharan Africa, plantain and banana provide up to 25% of the required
food energy (Swennen 1990). Plantain and banana are also an important source of
revenue for backyard producers and large-scale farmers.
The International Network for the Improvement of Banana and Plantain (INIBAP)
has outlined the major problems limiting the expansion of plantain production in West
and central Africa, and high postharvest losses are considered to be an important factor
(INIBAP 1988). Most of this loss is caused by inadequate postharvest handling and
storage practices. Losses are exacerbated by loads of mixed fruit ripeness, inefficient
packaging systems, insufficient transport vehicles and rough roads, which subject fruit to
both static and dynamic stress (Olorunda and Adelusola 1993). However, susceptibility of
Musa fruit to physical injury is influenced by factors such as cultivar (Chukwu 1997),
physiological maturity at harvest, temperature at harvest and handling practices
(Schoorl and Holt 1985, Seymour 1993). Environmental factors such as temperature,
relative humidity and air composition also affect potential storage life of harvested fruit
(Marriott et al. 1979, Proctor and Caygill 1985, Ferris 1992). Another factor that affects
the usability of Musa fruit is the inherent short green life of the fruit, since ripening
ushers in the end of fruit usefulness.
It is obvious that the control of postharvest losses is cheaper and perhaps less risky
than increasing production to offset losses. Screening Musa germplasm for variability in
physical strength and breeding for cultivars with a longer ripening period and injury
resistance offers a possible solution. This experiment is aimed at examining the
susceptibility of different genotypes of Musa fruit to postharvest harvesting and loading
stresses, and to determine their rate of respiration and ripening which are measures of
fruit usability index. The information will serve as guide for selecting appropriate
genotypes in the breeding programmes.