J. D. H. Keatinge

Agrobiodiversity for food security, health and income

By the year 2050, agriculture will have to provide the food and nutrition requirements of some 9 billion people. Moreover, to maintain that level of productivity indefinitely it must do so using environmentally sustainable production systems. This task will be profoundly complicated by the effects of climate change, increasing competition for water resources and loss of productive lands. Agricultural production methods will also need to recognize and accommodate ongoing rural to urban migration and address a host of economic, ecological and social concerns about the ‘high inputs/high outputs’ model of present-day industrial agriculture. At the same time, there is a need to confront the unacceptable levels of continuing food and nutrition insecurity, greatest in the emerging economy countries of Africa and Asia where poverty, rapid population growth and climate change present additional challenges and where agriculture is practiced primarily by small-scale farmers. Within this context, we here review science-based evidence arguing that diversification with greater use of highly valuable but presently under-valorised crops and species should be an essential element of any model for sustainable smallholder agriculture. The major points of these development opportunity crops are presented in four sections: agricultural farming systems, health and nutrition, environmental sustainability and prosperity of the populations. For each section, these crops and their associated indigenous knowledge are reported to bring benefits and services when integrated with food systems. In this paper, we conclude that not only a change in policy is needed to influence behaviours and practices but also strong leadership able to synergize the various initiatives and implement an action plan.

Vegetable breeding in Africa: constraints, complexity and contributions toward achieving food and nutritional security

Many Africans are presently confronted with nutritional insecurity as their diets are often deficient in essential vitamins and minerals owing to lack of sufficient consumption of fruit and vegetables. This results from problems of availability, affordability and lack of knowledge. There has been a substantive, long-term underinvestment in research and development of the horticultural sector in Africa with particular reference to those indigenous crops which are naturally high in nutritious vitamins and minerals. Lack of breeding effort, ineffective seed supply systems and an inadequate information, regulatory and policy framework have all contributed to the widespread occurrence of malnutrition on the continent. However, public sector research, development and policy amelioration efforts supported by a nascent private seed supply sector are now showing progress. Many new, improved, nutrient-dense indigenous and standard vegetable varieties are being released for which small-holder farmers are finding growing markets in both rural and urban settings. If such developments continue favourably for the next decade, it is expected that progress towards a reduction in poverty and malnutrition in Africa will be marked.

Vegetable gardens and their impact on the attainment of the Millennium Development Goals

The attainment of the Millennium Development Goals is at severe risk, owing to rising malnutrition and high child stunting and mortality rates, greater poverty, a large increase in the incidence of noncommunicable diseases, and lack of progress in womens empowerment. Here, the role of vegetable home, school, community, and disaster recovery gardens as a pro-poor and pro-environment intervention in the developing world is reviewed. This includes the contribution of vegetable gardens in improving food and nutritional security, generating additional income, providing employment, contributing to better health, and helping to empower disadvantaged groups in society. The implications of global research in the tropics and subtropics over the last 20–30 years are assessed over a wide geographic and linguistic range. The effectiveness and sustainability of such interventions are considered in the light of their contribution to the attainment of the Millennium Development Goals. Suggestions for potential new directions for research are made, and a call for better integration of effort in research and development between the agriculture, nutrition, and health sectors is presented as a key issue if rapid development progress is to be made and sustained.

Projecting annual air temperature changes to 2025 and beyond: implications for vegetable production worldwide

Data sets were accumulated of annual average maximum, minimum and mean air temperature from a range of sites worldwide, specifically from non-urban locations such as agricultural research institutes, universities and other rural or island locations for the period 1975–2011 or longer where data were available. The data sets were then analysed using linear regression to determine the rate and direction of change in temperature over the reference periods. This analysis was performed to provide vegetable scientists with likely future temperature change scenarios up to 2025 and 2050 (on the assumption that recent trends are maintained) so that breeding, agronomic and other related research programmes may better respond to potential challenges from abiotic and biotic stresses to vegetable production. Substantial variation was evident between sites and between time runs at specific sites. At some locations rapid increases in air temperature are projected, such as for sites in East Asia, but at other locations little change is evident; in rare cases, local cooling is shown. The implications of variability and change in air temperature in the context of constraints to vegetable production and the opportunities to exploit the range of genetic diversity available in climatically uncertain environments are discussed. It is believed that modern agricultural science can address successfully the problems raised by climate uncertainty, yet the lack of sufficient, immediate investment in horticultural disciplines worldwide places the world at severe risk of failing to attain effective food and nutritional security.

Overcoming biotic and abiotic stresses in the Solanaceae through grafting: current status and future perspectives

This paper reviews the status of the use of grafting in two solanaceous crops of global importance, tomato and eggplant, for the control of biotic and abiotic stresses. Flooding and soil-borne diseases cause severe crop losses of tomato during the hot and wet summer months in the lowland tropics. Asian Vegetable Research and Development Center (AVRDC) recommended since 2003 the use of eggplant rootstocks VI046103 (EG195) and VI045276 (EG203) for grafting tomato scions to provide a high degree of tolerance and resistance against flooding, bacterial wilt, root-knot nematodes and other soil-borne diseases. These two eggplant rootstocks and the tomato rootstock VI043614 (Hawaii 7996) are widely used in Southeast and East Asia for successful tomato production in both the tropical lowlands and highlands, providing significant economic returns to farmers. Given the rapid evolution of plant pathogens that might cause a breakdown of the limited rootstocks currently available, as well as the challenges of other abiotic stresses such as salinity and supra-optimal temperatures, it is necessary to expand the search for new rootstocks and evaluate new rootstock-scion combinations. Breeding and evaluation of appropriate rootstocks is still a matter of trial and error because desired rootstock traits, especially for abiotic stresses, are quite complex and regulated by multiple genes. Physiological and genetic markers to guide the selection process are still lacking but are essential to fast-track the identification of rootstocks with multiple benefits. This review supports an initiative to upgrade grafting technology through evaluation of a new and wider range of rootstocks sourced from the AVRDC genebank.