By Josephine Yaga
As human population rises, there is a tendency in decrease in the number of crops, creating vulnerability. This vulnerability emerges particularly when the variability within crops is also reduced. In developing countries, this loss of biodiversity is of concern. In light of this, several countries are tapping into underutilised and neglected crops to underpin food security.
Taro is the lowest of all root or tuber crops with an estimated yield of about 5.5t/ha on average. It is the food of small marginalised farmers, especially women, who grow the crop in swamps, irrigated terraces and/or on dry land for home consumption or domestic market. Taro therefore contributes significantly to food security, agricultural diversification and income generation in some developing countries.
In many Pacific Island countries, taro dominates the traditional farming system and is an integral part of social rituals. Taro and cocoyam are home garden crops in Africa, South and Central America, and the Caribbean for food security. But these crops are also increasingly being cultivated to satisfy export demand from markets in the USA and Europe. Situation in Asia is rather different as there is a widely perceived need to expand crop diversity to sustain food production, as their rice-based cropping system is under increasing pressure as population rises.
Clonally propagated crops are less adaptable to changes in environmental conditions than those propagated sexually. Changes rely on mutations or the chance of flowering, seed set and selection, which are rare events. Thus scientists or growers cannot easily manipulate the process. Thus in any region, diversity is low. To produce plants adaptable to new environments in light of climate change, pest and disease outbreaks, and market needs, it is necessary to broaden the genetic base.
To do this successfully requires cooperation between countries, the use of modern biotechnologies, and development of a network of scientists exchanging information and germplasm under the auspices of international treaties.
In line with this, the PNG National Agricultural Research Institute (NARI) is participating in a mega project funded by European Union to the value of approximately 5,812,000 Euro (K17,886,000). The project is titled Adapting clonally propagated crops to climatic and commercial changes. It commenced this year (2011) and will run for six years.
NARI is part of 16 partners in developing countries and four in Europe – bringing together scientists and smallholders, to adapt genotypes to forthcoming climatic change, and to exploit the potential of crops for product development.
The action required in this project is multidisciplinary and involves developing country scientists from various disciplines including agronomy, breeding, chemistry, human sciences, genetics, and virology. This action focuses on the use of modern biotechnologies to solve climatic adaptation problems, linking countries with centres of excellence that specialise in DNA fingerprinting, virus indexing, physico-chemical analyses and isotope studies for assessing drought resistance.
Taro and cocoyam will be used to construct the climatic adaptation model. The model shows how the genetic diversity of these two aroid species can be exploited to unlock their potential to overcome environmental and commercial challenges. During the process, farmers can increase income and improve food security.
The consortium comprises institutions with extensive experience in various clonally propagated root crop species. They include the Secretariat of the Pacific Community (SPC); four European institutions viz:- CIRAD (France), University of Maribor (Slovenia), University of Madeira (Portugal) and the DSMZ (Germany); 16 research institutions from 16 developing countries and Bioversity International as the associate.
The global partnership will create an efficient and effective network of institutions undertaking research to exploit the potential of clonally propagated crops. The objectives are to:
- assemble and share genetic resources of taro from diverse gene pools,
- promote international collaboration among breeders and farmers, and
- produce, by conventional and participatory breeding, new varieties of underexploited crops with high agronomic and commercial potential.
Selection of genotypes will be based on a combination of traditional and advanced procedures, including participatory methods.
PNG Project Scientist Jeffery Waki said country partners including NARI have received 50 genotypes in vitro from SPC (three tubes of each) in order to increase the genetic diversity from their breeding programmes.
Mr Waki said these genotypes will be field propagated, evaluated and selected for on-farm experiments. Thirty genotypes (a selection of the best local and introduced genotypes) will be distributed to five farmers in 10 villages (total of 50 lead farmers in each country).
In collaboration with Maribor, all country partners will initiate a breeding scheme and produce true taro seeds via targeted controlled crosses.