Leakey RRB

Leakey RRB
International Tree Foundation, UK · Vice President

DSc, PhD, BSc, NDA, CDA, FRGS
Working with Development charities and Networks, as well as writing and advocacy

About

394
Publications
147,598
Reads
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10,122
Citations
Introduction
Additional affiliations
September 2001 - March 2006
James Cook University
Position
  • Professor of Agroecology and Sustainable Development
May 2001 - September 2006
James Cook University Brisbane
Position
  • Director of Agroforestry and Novel Products Unit
January 2001 - March 2006
James Cook University
Position
  • Professor (Full)
Education
February 1998 - July 1998
University of Wales
Field of study
  • Tropical tree domestication
September 1970 - April 1974
University of Reading
Field of study
  • Vegetative regeneration of weeds
September 1967 - June 1970
Bangor University
Field of study
  • Agricultural Botany

Publications

Publications (394)
Article
Full-text available
A commentary to highlight the publication of a review paper on the Third Decade of the Domestication of indigenous food trees as new crops for African agriculture
Article
Full-text available
This paper follows the transition from ethnobotany to a deeper scientific understanding of the food and medicinal properties of African agroforestry tree products as inputs into the start of domestication activities. It progresses on to the integration of these indigenous trees as new crops within diversified farming systems for multiple social, ec...
Technical Report
Full-text available
Practical training on how to root stem cuttings of tropical trees
Article
Full-text available
International agricultural policies to address hunger and malnutrition in the tropics and sub-tropics have typically been based on approaches to the intensification of farming systems effective in industrialised economies where the social, economic, and environmental conditions and the infrastructure are very different to those in Africa. The conse...
Article
Full-text available
(Full document can be obtained via: http://www.fao.org/documents/card/en/c/cb2488en) EXECUTIVE SUMMARY Products and services derived from trees in forests, on farmland and within other landscapes provide benefits to hundreds of millions of people in the tropics, but these benefits from the trees and their genetic resources have not been well quan...
Article
Full-text available
Environmental degradation, loss of biodiversity and climate change threaten the stability of our planet. Inappropriate approaches to food production interact with hunger, malnutrition and extreme poverty, especially in the tropics and sub-tropics. These approaches, in turn, enhance social deprivation and limit rural development, both of which are d...
Article
Full-text available
Food production capacity lies at the heart of many of the ‘Big Issues’ facing our planet due to deforestation, land degradation and the failure of agriculture to be an “engine of economic growth” in the tropics and sub-tropics. To reverse the downward spiral of the “cycle of land degradation and social deprivation” that leads to hunger and poverty,...
Article
Full-text available
Main conclusion: Over the last 25 years, the process of domesticating culturally-important, highly-nutritious, indigenous food-tree species. Integrating these over-looked 'Cinderella' species into conventional farming systems as new crops is playing a critical role in raising the productivity of staple food crops and improving the livelihoods of p...
Preprint
Full-text available
Main conclusion Over the last 25 years the process of domesticating culturally-important, highly-nutritious, indigenous food-tree species. Integrating these overlooked 'Cinderella' species into conventional farming systems as new crops is playing a critical role in raising the productivity of staple food crops and improving the livelihoods of poor...
Conference Paper
Full-text available
Trees have a wide range of environmental/ecological benefits as well as producing numerous useful and marketable products
Article
Full-text available
The rooting of Allanblackia stem cuttings is typically slow and with the formation of very few roots. Irradiance has positive effects on the relative growth of plants and rooting ability, but there is no information relating to Allanblackia species. Stumps of Allanblackia floribunda Oliv. were grown under three levels of irradiance (2008 µmol m−2s−...
Preprint
Full-text available
To address the issues of food insecurity within the context of land degradation, extreme poverty and social deprivation, this review seeks first to understand the main constraints to food production on smallholder farms in Africa. It then proposes a highly-adaptable, yet generic, 3-step solution aimed at reversing the downward spiral which traps su...
Chapter
Full-text available
Trees have a different impact on soil properties than annual crops, because of their longer residence time, larger biomass accumulation, and longer-lasting, more extensive root systems. In natural forests nutrients are efficiently cycled with very small inputs and outputs from the system. In most agricultural systems the opposite happens. Agrofores...
Chapter
Full-text available
This final chapter emphasises that African smallholders currently operate as self-sufficient units virtually outside the cash economy, calling into question the wisdom of trying to impose economies of scale. Thus a different, multidimensional mindset is proposed - one based on the resilience and total productivity of multifunctional, socially appro...
Chapter
The second decade of agroforestry tree domestication (2003–2012) has been characterized by more detailed and intensive studies of some 16 research topics spanning many biophysical and social science disciplines, especially in clonal propagation and genetic characterization of tree-to-tree variation. Likewise, there has been substantial spread of th...
Chapter
Full-text available
A number of different approaches are taken to tree domestication and genetic improvement, but little appropriate research has been done on agroforestry tree species, especially those producing useful and marketable products (AFTPs). A new approach to developing clonal cultivars using simple vegetative propagation techniques is proving promising. Cu...
Chapter
Full-text available
With policy now lagging behind technology in the resolution of issues facing smallholder farmers in the tropics, the time has come to recognize the concepts of multifunctional agriculture—ones that meet many of the calls for more sustainable approaches to farming that address the key environmental, social and economic constraints to production and...
Chapter
Full-text available
Sustainable Intensification is especially important in Africa where the need is greatest. We present eleven targets for action, paying specific attention to the needs of poor smallholder farmers in Africa. We describe multi-cropping systems integrating new crops developed from culturally-important traditional food species that intensify and enhance...
Chapter
Full-text available
The ideotype concept has been developed and modified for a number of different crops, including forest trees, over the last 35 years. In recent years it has been used in the domestication of agroforestry trees producing Agroforestry Tree Products (AFTPs), as an aid to the multiple-trait selection of superior trees for cultivar development. For exam...
Chapter
Full-text available
Despite much progress, huge problems remain with billions of people still suffering from land degradation, food insecurity and poverty. While nearly half agricultural land has 10% tree cover, the area which can be described as “intensified agroforestry” is minute. This emphasizes the potential for dramatic improvement to replace conventional intens...
Chapter
An analysis of the factors leading to unsustainable agriculture and its associated problems of food insecurity, malnutrition and poverty, identifies a downward spiral of land degradation and social deprivation which is associated with lower crop yields, loss of biodiversity and agro-ecological function, and declining farmer livelihoods. This spiral...
Chapter
Full-text available
The current definition of agroforestry views it as a set of stand-alone technologies in which trees are sequentially or simultaneously integrated with crops and/or livestock. This falls far short of its ultimate potential as a way to mitigate deforestation and land degradation and thus alleviate poverty. A different view, however, is that agrofores...
Chapter
Full-text available
Population pressures, exacerbated by a range of social and political factors, have resulted in widespread deforestation, land degradation and the cultivation of marginal and sloping land. The resultant declining soil fertility and soil erosion threaten the sustainability of small-scale farming, especially as external nutrient inputs are seldom avai...
Chapter
Full-text available
This update presents a growing body of additional studies that examine the dynamic interactions of organisms in agroforestry systems and in landscapes. Understanding the roles of this biodiversity is critical to an understanding of how to manage agroecosystems sustainably in ways that give them a unique advantage over the rather prescribed land-man...
Chapter
Full-text available
Shifting agriculture in the tropics has been replaced by sedentary smallholder farming on a few hectares of degraded land. To address both low yields and low income, the soil fertility, the agroecosystem functions, and the source of income can be restored by diversification with nitrogen-fixing trees and the cultivation of indigenous tree species t...
Chapter
Full-text available
New initiatives in agroforestry are seeking to integrate into tropical farming systems indigenous trees whose products have traditionally been gathered from natural forests. This is being done in order to provide marketable products from farms that will generate cash for resource-poor rural and peri-urban households. This poverty-alleviating agrofo...
Chapter
The middle to late 1990s was the turning point from agroforestry as a system primarily aimed at soil fertility improvement and a domestic source of poles, wood fuel, and timber to one where enrichment with domesticated indigenous trees producing high-value marketable products diversifies the farming system and initiates income generation � a change...
Chapter
Full-text available
The domestication of trees for agroforestry approaches to poverty alleviation and environmental rehabilitation in the tropics depends on the expansion of the market demand for their non-timber forest products (NTFPs). This paper reviews published data on the nutritive values of the flesh, kernels, and seed-oils of the 17 fruit tree species that hav...
Chapter
Full-text available
Ten fruit and kernel traits were measured in 152 Irvingia gabonensis and 293 Dacryodes edulis trees from six villages in Cameroon and Nigeria. Frequency distribution curves were used to examine the range of variation of each trait of each species in each village and aggregate them into national and regional populations. There were differences betwe...
Chapter
Full-text available
Tree products other than timber are conventionally described as non-timber or non-wood forest products (NTFP/ NWFP). For legal and trade reasons, this chapter proposes the need to distinguish those products derived from common-property resources from those, often of the same species, derived from trees cultivated on private farm land, and suggests...
Chapter
Full-text available
Thousands of wild species are recognized as having culturally important edible fruits, nuts, and leaves with much higher nutrient content than the major cereal and root crops that dominate global diets. This indicates their potential as new crops for the diversification and enrichment of diets. This has now started to be internationally recognized...
Chapter
Full-text available
Agroforestry tree domestication emerged as a farmer-driven, market-led process in the early 1990s and became an international initiative. A participatory approach now supplements the more traditional aspects of tree improvement, and is seen as an important strategy towards the Millennium Development Goals of eradicating poverty and hunger, promotin...
Chapter
Full-text available
In recent years, progress has been made with domestication of Triplochiton scleroxylon, an important timber tree of the moist West African forests. Seed viability has been extended from a few weeks to many months by appropriate drying and cold storage. Seed supply is irregular, but the successful development of vegetative propagation methods has pr...
Chapter
By combining horticultural skills and techniques with both Traditional Knowledge and the use of modern genetics, tree domestication has emerged as a novel, farmer-driven approach to agroforestry that captures both local knowledge at the village level and the genetic traits associated with the genetically elite, sexually mature trees. Furthermore, b...
Chapter
Full-text available
Stem cuttings of five tree species from dry and semi-arid woodlands (Acacia tortilis, Prosopis juliflora, Terminalia spinosa, Terminalia brownii and Albizia guachapele) and seven species from moist tropical forests (Cordia alliodora, Vochysia hondurensis, Nauclea diderrichii, Ricinodendron heudelotii, Lovoa trichiliodes, Gmelina arborea, Eucalyptus...
Chapter
Full-text available
Methods were developed to quantify variation in the fruit, nut and kernel traits using the fruits from four trees of Irvingia gabonensis, an indigenous fruit tree of west and central Africa. The measurement of 18 characteristics of 16�32 fruits per tree, identified significant variation in fruit, nut and kernel size and weight, and flesh depth. Dif...
Chapter
Full-text available
By integrating a farmer-driven, on-farm approach with laboratory-based genetics research, agroforestry tree domestication is maximizing the benefits from the development of clonal cultivars, while minimizing the risks. In developing this strategy, special consideration is given to the development of practical techniques based on the relevant use of...
Chapter
Full-text available
The ability of auxin-treated Triplochiton scleroxylon cuttings to root was affected by the prior management of potted stockplants. In undecapitated single-stem stockplants more cuttings from upper rather than lower mainstem nodes rooted; a difference paralleled by leaf water potential immediately after severance, although there was also a positive...
Chapter
Full-text available
Stockplants of Triplochiton scleroxylon were grown in controlled-environment cabinets at the Institute of Terrestrial Ecology, Edinburgh, to test the effects of stockplant llumination on the rooting ability of leafy stem cuttings. The environmental variables were: (1) irradiance (PAR5106, 202 and 246 μmol m22 s21) with a uniform light quality (red:...
Chapter
Full-text available
Techniques of macro-propagation have been used for millennia, however it was difficult to identify clear principles applying to all species. Research over the last 20-30 years has provided better understanding of the numerous pre- and post-severance interacting factors � both morphological and physiological � and led to greater clarity. This resear...
Chapter
Full-text available
Studies of tree-to-tree variation in fruit traits are a pre-requisite for cultivar development. Fruits were collected from each of 63 marula (Sclerocarya birrea) trees in Bushbuckridge, South Africa and from 55 trees from the North Central Region of Namibia. The South African trees were in farmers’ fields, communal land and natural woodland, at thr...
Chapter
Full-text available
An understanding of the inter-relationships between the traits characterising tree-to-tree variation in fruits and kernels is fundamental to the development of selected cultivars based on multiple trait selection. Using data from previously characterised marula (Sclerocarya birrea) trees in Bushbuckridge, South Africa and North Central Region of Na...
Chapter
Full-text available
As part of a wider study characterizing tree-to-tree variation in fruit traits as a pre-requisite for cultivar development, fruits were collected from each of 63 marula (Sclerocarya birrea) trees in Bushbuckridge, South Africa and from 55 trees from the North Central Region of Namibia. The nuts were removed from the fruit flesh, and the kernels ext...
Chapter
Full-text available
The domestication strategy and vegetative propagation techniques used for agroforestry trees have been widely adopted by many researchers. Certainly, the low-tech polypropagator has spread across the globe and can be found in remote locations in all corners of Africa, the Amazon, the high Andes, Central America, Southeast Asia, Far East and Oceania...
Chapter
The participatory domestication of agroforestry trees as an incentive to alleviate poverty, malnutrition, hunger and land degradation has to be linked to the commercialization of the products in ways that ensure that the farmers are the beneficiaries of their germplasm improvement activities, as well as from the marketing of the products. Currently...
Chapter
Full-text available
This study obtained quantitative data on fruit and nut traits in two indigenous fruit trees from West Africa (Irvingia gabonensis and Dacryodes edulis), which have led to the identification of trees meeting ideotypes based on multiple morphological, quality and food property traits desirable in putative cultivars. The same data also indicate change...
Chapter
Full-text available
Internationally, there is interest in increasing the trade in “green” market products, such as organic, fair trade, reduction of forest degradation for reduced deforestation and mitigation of climate change, and environmental goods and services. This crucially needs to be extended to the many poor, hungry and marginalized smallholder farmers in dev...
Chapter
Full-text available
Participatory domestication of indigenous tropical trees producing useful and marketable products has been developed to replenish the resource depleted by land clearance for agriculture. The domestication programme which was initiated in the 1990’s has now become a global programme aimed at the alleviation of poverty and malnutrition. However when...
Chapter
Full-text available
In response to farmers’ interest in the cultivation of indigenous trees that produce traditionally and culturally important tree products, this chapter place the outcomes resulting from participatory, decentralized, tree domestication; community capacity building through Rural Resource Centres, and the development of a value chain based on associat...
Chapter
Full-text available
The International Assessment of Agricultural Knowledge, Science and Technology for Development (IAASTD) defined multifunctional agriculture as the inescapable interconnectedness of agriculture’s different roles and functions: namely the production of food and nonfood commodities; delivery of environmental services; the improvement of rural liveliho...
Chapter
Full-text available
The benefits of the Green Revolution have come at a high environmental and social cost in the tropics, with land degradation and poverty now the main constraints to productivity in developing countries. This results in a complex downward spiral of interacting environmental, social and economic factors which gives rise to a “yield gap” between the p...
Chapter
Full-text available
Agroforestry can be used to improve the productivity of staple food crops by improving soil fertility and promoting agroecosystem function. The domestication of agroforestry trees producing marketable products then intensifies the agroforestry system and leads to marketing, trade, and business opportunities that improve farmers’ livelihood. Togethe...
Book
Full-text available
This book explores the potential benefits of Multifunctional Agriculture to the social, economic and environmental sustainability of tropical agriculture and its potential to deliver the new Sustainable Development Goals. In a world increasingly challenged by the need to integrate and understand highly specialized knowledge in a multidisciplinary w...
Article
Full-text available
To address ongoing issues of hunger, malnutrition, poverty and land degradation in Africa, smallholder farmers are developing Socially Modified Crops as part of a 3-step approach to a multifunctional farming system that impact positively on the social, economic and environmental constraints to farm productivity responsible for the gap between poten...
Chapter
Full-text available
We execute tree “domestication” as a farmer-driven and market-led process, which matches the intraspecific diversity of locally important trees to the needs of subsistence farmers, product markets, and agricultural environments. We propose that the products of such domesticated trees are called Agroforestry Tree Products (AFTPs) to distinguish them...
Chapter
Full-text available
More than 420 research papers, involving more than 50 tree species, form the literature on agroforestry tree domestication since the 1992 conference that initiated the global programme. In the fi rst decade, the global effort was strongly led by scientists working in humid West Africa; it was then expanded to the rest of Africa in the second decade...
Chapter
Full-text available
The ideotype concept has been developed and modified for a number of different crops, including forest trees, over the last 35 years. In recent years it has been used in the domestication of agroforestry trees producing Agroforestry Tree Products (AFTPs), as an aid to the multiple-trait selection of superior trees for cultivar development. For exam...
Chapter
Full-text available
Trees have a different impact on soil properties than annual crops, because of their longer residence time, larger biomass accumulation, and longer-lasting, more extensive root systems. In natural forests nutrients are efficiently cycled with very small inputs and outputs from the system. In most agricultural systems the opposite happens. Agrofores...
Chapter
An analysis of the factors leading to unsustainable agriculture and its associated problems of food insecurity, malnutrition and poverty, identifies a downward spiral of land degradation and social deprivation which is associated with lower crop yields, loss of biodiversity and agro-ecological function, and declining farmer livelihoods. This spiral...
Chapter
Full-text available
Despite much progress, huge problems remain with billions of people still suffering from land degradation, food insecurity and poverty. While nearly half agricultural land has 10% tree cover, the area which can be described as “intensified agroforestry” is minute. This emphasizes the potential for dramatic improvement to replace conventional intens...
Chapter
Full-text available
Sustainable Intensification is especially important in Africa where the need is greatest. We present eleven targets for action, paying specific attention to the needs of poor smallholder farmers in Africa. We describe multi-cropping systems integrating new crops developed from culturally-important traditional food species that intensify and enhance...
Chapter
With policy now lagging behind technology in the resolution of issues facing smallholder farmers in the tropics, the time has come to recognize the concepts of multifunctional agriculture—ones that meet many of the calls for more sustainable approaches to farming that address the key environmental, social and economic constraints to production and...
Chapter
Full-text available
This final chapter emphasises that African smallholders currently operate as self-sufficient units virtually outside the cash economy, calling into question the wisdom of trying to impose economies of scale. Thus a different, multidimensional mindset is proposed - one based on the resilience and total productivity of multifunctional, socially appro...
Article
To address on-going issues of hunger, malnutrition, poverty and land degradation in Africa, smallholder farmers are developing Socially Modified Crops as part of a 3-step approach to a multifunctional farming systems that impact positively on the social, economic and environmental constraints to farm productivity responsible for the gap between pot...
Chapter
Full-text available
Cap. 8-El valor de la diversidad y la calidad de la semilla: Boshier, Mesén, Hughes y Leakey 283 OFI-CATIE / Aunque la reforestación ha aumentado en la región, muchas plantaciones han sido establecidas sin considerar la fuente de la semilla que se usa, ya sea por desconocimiento o por falta de disponibilidad de fuentes comprobadas de semilla. Así,...
Chapter
Full-text available
Techniques of macropropagation have been used for millennia; however, it was difficult to identify clear principles applying to all species. Research over the past 20–30 years has provided better understanding of the numerous pre and postseverance interacting factors – both morphological and physiological – and led to greater clarity. This research...
Article
Full-text available
Shifting agriculture in the tropics has been replaced by sedentary smallholder farming on a few hectares of degraded land. To address low yields and low income both, the soil fertility, the agroecosystem functions, and the source of income can be restored by diversification with nitrogen-fixing trees and the cultivation of indigenous tree species t...
Article
Full-text available
Internationally, there is interest in increasing the trade in ‘green’ market products, such as organic, fair trade, reduction of deforestation and forest degradation/reduction of deforestation and forest degradation+ for reduced deforestation and mitigation of climate change, and environmental goods and services. This crucially needs to be extended...
Article
Full-text available
Products and services provided by trees in forests and farmland support the needs and promote the wellbeing of hundreds of millions of people in the tropics. Value depends on managing both the diversity of tree species present in landscapes and the genetic variation within these species. The benefits from trees and their genetic resources are, howe...