Principles of Plant Genetics and Breeding

408 CHAPTER 22
Subsequent studies investigated the feasibility of reducing the levels of fishmeal in commercial diets when “Obatanpa” was the
source of maize. Results of the studies indicated that the use of “Obatanpa” allowed the level of fishmeal (an expensive high protein
ingredient in Ghana) to be reduced from 19.5% to 13.5%, whilst still maintaining good performance. The use of “Obatanpa”
in broiler diets resulted in a significant economic advantage because of the reduced use of fishmeal – due mainly to the huge price
disparity between QPM and fishmeal.
Processed food from normal maize and QPM
Kenkey is a popular local food in Ghana. It is made from fermented maize meal. We studied the effect of processing and cooking
on the nutritional quality of kenkey made from normal maize or QPM (Ahenkora et al. 1995). The QPM, “Obatanpa”, and the
normal maize, “Okomasa”, were processed into kenkey. Weaning rats were fed ad libitum on kenkey-based diets, which served
as the sole source of protein and amino acid, for 28 days. Analysis of samples of the kenkey revealed that processing and cooking
raw grains into kenkey reduced the lysine content by 13% and the tryptophan content by 22% (Ahenkora et al. 1995). However,
kenkey from QPM contained 51% more lysine and 63% more tryptophan than kenkey from normal maize. The individual average
gain by rats fed on a QPM kenkey diet was 37.2 g compared with 16.2 g for NM kenkey – a 2.3-fold difference. Rats fed the
QPM diet had a better feed conversion ratio and higher protein efficiency ratio values than their counterparts fed a normal maize
kenkey diet.
Agricultural technology/nutrition impact study
A series of studies investigated the impact of QPM utilization on community-based agricultural technology interventions in the
Ejura-Sekodumasi District, Ashanti Region, Ghana. The study was done through the Ministry of Health Nutrition Division with
collaboration from other agricultural and health institutions in Ghana particularly the CRI, Ministry of Food and Agriculture
(MOFA), and SG2000. The results showed that QPM enhanced growth relative to normal maize when fed to children.
Breeding challenges related to QPM
A series of experiments were conducted to dispel some of the doubts, myths, and fallacies concerning QPM (Twumasi-Afriyie
et al. 1996).
1 QPM produces a lower grain yield than NM counterparts. In Ghana, it was shown that QPM varieties could produce better
yields than their normal counterparts.
2 Lysine and tryptophan are “heat labile” and would be destroyed during processing, thus QPM will lose its nutritional
advantage during processing into local dishes. We demonstrated that the nutritional advantage was maintained when
QPM was processed into the most popular local dishes (Ahenkora et al. 1995).
3 QPM is conferred by a recessive gene and thus will lose its nutritional advantage in farmers’ production plots, which
are normally planted on small areas. We conducted an experiment in which we surrounded a 1-acre field of QPM with a
yellow endosperm NM with the same maturity, and allowed the two to cross freely. Results from 2 years of data at several
locations showed a maximum of 10% contamination by the NM. The contamination was most pronounced within 12 m
of the QPM field nearest the NM, and was most serious at the southwestern sector of the field due to the prevailing wind.
The nutritional quality of the bulked grain from the most contaminated lot was still not significantly different from the noncontaminated
QPM, based on a rat-feeding study.
4 QPM will not store well at the farm level. From our study, when weevils were introduced into grains of NM or QPM grain,
there was no difference in the extent of damage incurred. All samples were equally damaged in a short time period.
Moreover, it was detected that, in general, post-harvest handling was very poor in Ghana, and that available improved
technology if followed could enable farmers to store both NM and QPM with minimal problems.
5 Marketing will be difficult because QPM lacks visible identifiers that could facilitate sale at a higher price to offset additional
costs of production. In fact, there was no additional cost of production of “Obatanpa” as it produced higher yields
than its normal counterparts under identical recommended practices. Agronomic performance per se became a driving
force behind the adoption of this variety. Special marketing channels developed for “Obatanpa”. Private purchasing agents
began to market “Obatanpa” to satisfy the demands of commercial users such as food and feed processors and relief agencies.
The private purchasing agents linked with producers and guaranteed the quality of “Obatanpa” to the users.
Current efforts in QPM development in Africa
The CIMMYT recommenced QPM development in 1997 partly due to the success achieved in Ghana. Current efforts in QPM
development in sub-Saharan Africa involve several national agricultural research institutes and increasing numbers of private
seed companies. QPM development and deployment largely follows the Ghana model involving multidisciplinary and multiinstitutional
approaches in germplasm development, nutritional studies, variety releases, seed production, and agricultural