Content uploaded by Gea Galluzzi
Author content
All content in this area was uploaded by Gea Galluzzi on Feb 16, 2015
Content may be subject to copyright.
Content uploaded by P. Eyzaguirre
Author content
All content in this area was uploaded by P. Eyzaguirre on Apr 29, 2014
Content may be subject to copyright.
REVIEW PAPER
Home gardens: neglected hotspots of agro-biodiversity
and cultural diversity
Gea Galluzzi
•
Pablo Eyzaguirre
•
Valeria Negri
Received: 13 January 2010 / Accepted: 6 September 2010
Springer Science+Business Media B.V. 2010
Abstract Over the last two decades, the importance of conserving genetic resources has
received increasing attention. In this context the role of home gardens as repositories of
biological diversity has been acknowledged but still a comprehensive, interdisciplinary
investigation of their agro-biodiversity is lacking. Home gardens, whether found in rural or
urban areas, are characterized by a structural complexity and multifunctionality which
enables the provision of different benefits to ecosystems and people. Studies carried out in
various countries demonstrate that high levels of inter- and intra-specific plant genetic
diversity, especially in terms of traditional crop varieties and landraces, are preserved in
home gardens. Families engage in food production for subsistence or small-scale mar-
keting and the variety of crops and wild plants provides nutritional benefits. At the same
time, home gardens are important social and cultural spaces where knowledge related to
agricultural practices is transmitted and through which households may improve their
income and livelihoods. The present article summarizes available literature on the bio-
logical and cultural significance of agro-biodiversity in home gardens. It discusses future
constraints and opportunities in home garden research, in the prospect of defining and
promoting their role in conservation of agricultural biodiversity and cultural heritage.
Keywords Home gardens Agro-ecosystems In situ conservation Agro-biodiversity
Landraces
G. Galluzzi (&)
Bioversity International, Office of the Americas, c/o CIAT, km 17 Recta Cali- Palmira, Cali, Colombia
e-mail: g.galluzzi@cgiar.org
P. Eyzaguirre
Bioversity International, Via dei Tre Denari 472a, 00057 Maccarese, Rome, Italy
V. Negri
Department of Applied Biology, University of Perugia, Borgo XX Giugno 74, 06121 Perugia, Italy
123
Biodivers Conserv
DOI 10.1007/s10531-010-9919-5
Introduction
Conservation of agro-biodiversity
While it is commonly acknowledged that the diversity of life forms in the natural world
is being depleted under increasing human pressure on the Earth’s ecosystems, there is
much less awareness that agro-biodiversity is under similar threats. Agro-biodiversity is a
subset of natural biodiversity which includes the plant genetic resources used for food and
agriculture (cultivars, landraces, ecotypes, weedy races and wild relatives) (Negri et al.
2009). Maintenance of genetic variation within agricultural crops provides a broad range
of essential goods and services which support ecosystem functioning, resilience and pro-
ductivity (Tilman 1999, 2000), and for this reason it has become a core principle of
sustainable agriculture and agro-ecology (Altieri and Merrick 1987; Paoletti 2001;
Le Coeur et al. 2002; Marshall and Moonen 2002). Agro-biodiversity also provides farmers
and breeders with raw material for continuously selecting and adapting crops to changing
environmental conditions or to the needs of a growing human population (IPGRI 1993).
This continuous process of experimentation leads to an exceptionally strong connection
between agro-biodiversity and people, cultures, and landscapes.
The growing concern around the loss of agro-biodiversity in the last decades has fuelled
global efforts to improve conservation actions through a number of international docu-
ments and agreements. The Convention on Biological Diversity (CBD 1992) intends to halt
the current loss of plant and crop diversity while contributing to poverty reduction and
sustainable development. The Global Strategy for Plant Conservation (GSPC 2002) aims
by 2010 to conserve ‘‘70% of the genetic diversity of crops and other major socio-
economically valuable plant species’’, while maintaining the ‘‘associated indigenous and
local knowledge’’. The International Treaty on Plant Genetic Resources for Food and
Agriculture (ITPGRFA 2001) specifically focuses on the ‘‘conservation and sustainable use
of plant genetic resources for food and agriculture and the fair and equitable sharing of the
benefits arising out of their use’’. It requires contracting parties to ‘‘promote or support […]
farmers’ and local communities’ efforts to manage and conserve on-farm their plant
genetic resources’’.
In ex situ conservation through gene banks or botanical gardens, the removal of species
from their natural ecological and evolutionary context results in a ‘‘static’’ conservation in
which evolutionary and adaptive potential are frozen. Only a third of the species conserved
in gene banks are landraces or primitive cultivars while minor, underutilized species and
wild relatives are under-represented (Hammer et al. 2004). On the contrary, a major portion
of agro-biodiversity thrives in complex agro-ecosystems which are most often managed by
small farmers worldwide. On farm conservation in their fields and gardens is a ‘‘dynamic’’
solution which ensures the continuous adaptation of species and landraces within their
changing environment and relies upon both human and biological components of the
ecosystem.
In this context, this study focuses on in situ conservation of agro-biodiversity in those
small but highly diversified ecological niches generally known as home gardens. These
complex microenvironments (for average sizes see Table 1), traditionally integrated within
a larger surrounding ecosystem (Gliessman 1990a; Eyzaguirre and Linares 2004) have
been described as sustainable and diversified niches shaped by a close interaction between
nature and human cultures: ‘‘[A] village with its home gardens is not merely a dwelling-
place but also an important agro-ecosystem. It is an integrated unit in which the solar
Biodivers Conserv
123
energy is channelled through the plants to animals and man, and matter is cycled and
recycled’’ (Soemarwoto et al. 1975).
The study of home gardens as distinct ecological and cultural entities was initiated in
the tropics of South East Asia about 25 years ago (Soemarwoto et al. 1975; Stoler 1975;
Sommers 1978). Since then, research has concentrated mostly on developing countries and
has rarely focused on assessing home gardens’ importance as repositories of crop genetic
diversity. This gap in research is critical particularly when considering the data reviewed in
this study, which instead point out that home gardens are crucial reservoirs of agro-
biodiversity—at inter- and intra-specific levels—within diversified environmental and
cultural contexts (Eyzaguirre and Watson 2001; Guarino and Hoogendijk 2004).
Focusing on plants, this study aims to review the available literature on home gardens’
agro-biodiversity and to highlight their relevance in cultural and socio-economic terms.
Challenges and opportunities for improved research, monitoring and management of
Table 1 Descriptive data on home gardens from studies in different countries
Country(region) N. home
gardens
surveyed
Average
Size
(m
2
)
Average no.
cultivated
species/garden
Predominant plant use Source
Austria, Osttirol
region
196 116 10 Mostly ornamentals, followed
by spices, pickles and fruit
(Vogl-
Lukasser
and Vogl
2004)
China
(Xishuangbanna
Dai Prefecture)
10 199 18 Mostly edible plants (Yongneng
et al. 2006)
Ghana N/A 3750 45 Cereals, legumes and other
edibles, spices and medicinal
plants, ornamentals
(Bennett-
Lartey
et al. 2001)
Guatemala 47 90–2500 6 Food and ornamentals, fodder
crops
(Leiva et al.
2001)
Hungary 323 571 18 Mostly fruit trees, followed by
horticultural and fodder spp.
(Birol et al.
2005a)
India (North East,
Barak Valley)
50 3000 23.5 Mostly fruits and medicinal
spp.
(Das and Das
2005)
Nepal 134 418 33 Vegetables, followed by fruit
and fodder
(Sunwar
et al. 2006)
Papua New
Guinea
700 817 N/A Vegetables and other edible
species
(Vasey 1985)
Peru (Nuevo
Triunfo)
24 2944 16.3 Fruits, followed by other food
and medicinal plants
(Coomes and
Ban 2004)
Russia 712 2550 N/A Potatoes and vegetables and
small livestock
(Seeth et al.
1998)
South Africa 63 4000 12 Fruits, morogos (wild
spinaches), other edible
plants
(High and
Shackleton
2000)
Venezuela 150 6000 16 Mostly edible species (Quiroz et al.
2001)
Vietnam 120 1045 45 Mostly medicinal, followed by
vegetable and fruit crops
(Trinh LN
et al. 2001)
Biodivers Conserv
123
within-garden agro-biodiversity are identified and recent trends in policy and society which
may affect its conservation within home garden systems are also discussed.
Biological features
Complexity and multi-functionality
Home gardens occur in regions with either high and low human population densities and
are always located in proximity of human dwellings, often delimited from their sur-
roundings by hedges, fences or other barriers. The more or less sharp separation, coupled
with repeated tending from the household create specialized edaphic, microclimatic and
biotic conditions which make home gardens markedly different from the surrounding
landscape (Guarino and Hoogendijk 2004). Countryside home gardens contribute to the
functioning and sustainability of the larger agricultural ecosystem (Engels 2001), providing
services such as pollination, refuge for micro- and macro-fauna and allowing for gene-flow
between plant populations inside and out of the garden. The increasingly important urban
gardens, which are no longer connected to larger agro-ecosystems, contribute to improving
air quality, reducing CO
2
emissions and temperatures, providing citizens with livelihood
opportunities as well as social and recreational activities (Van Veenhuizen 2006; Viljoen
et al. 2009).
Defining an average size for home gardens is context-dependent; different agroeco-
logical and socio-economic conditions determine significant variations across agro-
ecosystems (see Table 1). In general, where home gardens represent a niche within larger
farming systems, their size is to some degree proportional to the size of the overall farm
(Guarino and Hoogendijk 2004). Gardens in cities, which do not have an immediate
connection with larger fields, are a more fragmented resource (Gaston et al. 2005) whose
size largely depends on the competition for land from buildings and infrastructural
development (Nin
˜
ez 1984; Vasey 1985; Linares 1996).
Traditional home gardens typically have a multilayered arrangement, resembling an
agro-forestry system, which brings different plant species together in a temporal and/or
spatial succession; this stratified and dynamic architecture, more than the identity of single
species, has been shown to make a home garden a sustainable and resilient ecosystem
(Smith et al. 2006) in which differentiated root structures utilize nutrients from various soil
levels and both ground and aerial space are efficiently utilized (Eyzaguirre and Linares
2004). Control of soil erosion and soil fertility are often maximized by the presence of
trees, with fallen leaves providing natural mulching and the accumulation of humus. A
generally reduced application of chemical fertilizers and pesticides protects natural habitats
for wild flora and fauna (Daniels and Kirkpatrick 2006) and maintains high micro-
organism diversity (Birol et al. 2005a).
Inter-specific genetic diversity
Home gardens’ specific relevance for conservation purposes resides in their capacity to
represent agro-biodiversity at multiple levels (Hodgkin 2001) over small spaces. By har-
bouring species with different life cycles and domestication status—wild, semi-domesti-
cated and domesticated—which require diversified cultivation practices and serve multiple
purposes (food, fodder, medicine, fuel and fibre, ritual, or ornamental), home gardens
become living storehouses for a variety of end-products. Studies carried out in home
Biodivers Conserv
123
gardens of various regions have recorded notable richness of species and varieties
(Tables 1 and 2).
In terms of composition, high diversity of species with an immediate use in the
homestead is the most prominent feature of home gardens (Hoogerbrugge and Fresco
1993). Predominance of fruit trees is common, particularly when these are crucial for the
diet of household members in terms of vitamins and fibres (Mitchell and Hanstad 2004);
other edible species, wild or domesticated, are the next most represented category
(Table 2).
Home gardens are often utilized as testing plots for new crops, as nurseries for plantlets
later destined for planting in open fields and as sites for domestication of weedy forms
(Kulpa and Hanelt 1981; Leiva et al. 2001), which may also be used directly within the
household (Table 3). Minor or ‘‘relic’’ crops never or no longer cultivated in larger
commercial fields have been found in carefully surveyed home gardens: this is the case for
lima bean in Cuba, sponge gourd in Nepal (Hodgkin 2001), Lavatera arborea L. in the
small island of Linosa off coast from Sicily (Hammer et al. 1997) and Camelina sativa
Crantz, Raphanus sativus L. var. oleiformis, Panicum miliaceum L. in Poland (Kulpa and
Hanelt 1981; Nowosielka and Podyma 2001).
Intra-specific plant genetic diversity
The predominant subsistence orientation of garden cultivation and the consequent greater
flexibility in farming practices encourages the introduction and maintenance of wild
species (Guijt et al. 1995), indigenous crops (Juma 1989) and traditional varieties
(Negri 2003; Negri and Polegri 2009). This results in significant intra-specific diversity
(Eyzaguirre and Linares 2004) which not only increases a species’ chance for adaptation
and survival over time (Soule
´
1987; Nunney and Campbell 1993), but also provides crucial
material for breeding (Tanksley and McCouch 1997; Feuillet et al. 2008) and for estab-
lishing, complementing or restoring germplasm collections (Castin
˜
eiras et al. 2007).
The presence of crop wild relatives in particular allows gene exchange with the crops
themselves: natural crosses between domesticated forms and their wild or weedy relatives
still consistently occur in or around home gardens (Hammer et al. 1999) and wild germ-
plasm has often been utilized by farmers to create and improve crops, by experimenting in
back-yard gardens (Hughes et al. 2007).
Landraces in home gardens are grown either in isolation or in combination with modern
cultivars from the seed market (Table 4). Landraces are highly variable, culturally selected
populations which lack ‘‘formal’’ crop improvement. They carry specific adaptation to the
environmental conditions where they belong and are closely associated with the people
who developed and grow them (Negri et al. 2009). A landrace’s high genetic diversity is a
defence against pests, diseases and environmental changes and makes landraces more
suitable than commercial varieties for non-industrial agricultural systems (Negri 2005).
Trees are usually found in low numbers in each garden, mostly because of their greater
demand for space: 40% of autochthonous fruit tree varieties surveyed in central Italy are
found as single individuals in single gardens (Pavia et al. 2009). This means the overall
intra-specific diversity of fruit tree species is captured by considering a series of home
gardens, each with a low number of individuals, in a given area. For other crops numbers
are different (Table 2): Italian home gardens maintain many landraces of common bean,
Phaseolus
spp., (Hammer et al. 1986; Negri 2003), an average of 10 native potato varieties
per household have been reported in the Andean region (Brush et al. 1992), up to 10
cassava varieties are kept in Javanese gardens (Soemarwoto et al. 1975).
Biodivers Conserv
123
Table 2 Different garden crops surveyed in a variety of regions and number of local types within each
genus or species (landraces for most crops and individuals for fruit trees)
Country/
region
Genus or species N. types (landraces or
individuals)
Source
Cuba Phaseolus lunatus L. 59 (Castin
˜
eiras et al.
2007)
Guatemala Capsicum spp. 34 (Guzma
`
n et al.
2005)
Pouteria sapota (Jacq.) H.E.Moore &
Stearn
5 (Leiva et al. 2001)
Italy/Latium Castanea sativa Mill. 3 (Pavia et al. 2009)
Corylus avellana L. 4
Malus domestica Baumg. 38
Prunus armeniaca L. 3
Prunus avium (L.) L. 21
Prunus cerasifera Ehrh. 8
Prunus cerasus L. 4
Prunus persica (L.) Batsch 11
Pyrus communis L. 29
Punica granatum L. 3
Vitis vinifera L. 4
Italy/Carnia Petroselinum crispum (Mill.) Nyman 2 (Laghetti et al.
2004)
Zea mays L. 2
Italy/Veneto Allium sativum L. 2 (Laghetti et al.
2004)
Asparagus officinalis L. 10
Castanea sativa L. 7
Juglans regia L. 2
Phaseolus spp. 4
Pisum sativum L. 3
Prunus avium (L.) L. 6
Solanum tuberosum L. 10
Italy/Sicily Alliums spp. 8 (Hammer et al.
1986)
Avena spp. 7
Beta vulgaris L. 5
Brassica spp. (including wild
brassicas)
17
Capsicum annuum L. 2
Chicorium spp. 13
Cicer arietinum L. 7
Cucurbita spp. 8
Cucumis melo
L. 4
Eruca sativa Hill 2
Foeniculum vulgare Hill 2
Hedysarum coronarium L. 2
Hordeum vulgare L. 8
Lactuca sativa L. 7
Lagenaria siceraria Standl. 7
Biodivers Conserv
123
Generally, numbers and identities of local cultivars and variation in morphological
characteristics within crop populations are the starting point for any assessment of the
amount of genetic diversity; measures of richness, evenness and divergence and direct
measurements of genetic variation with molecular markers contribute to a more accurate
picture. Only in rare cases have molecular measures been applied to garden-size crop pop-
ulations, although some interesting results do exist. Species richness and abundance mea-
sured in upland and lowland Mexican gardens revealed diversity indexes (Shannon-Weiner)
of 3.84 and 2.43, respectively, (Gliessman 1990a), comparable to those recorded in Costa
Rica—3.55 (Gliessman 1990b)—and India—2.44 (Eyzaguirre and Linares 2004). Molecular
analyses detected substantial diversity among landraces of tomato (Solanum lycopersicum
L.), cowpea (Vigna unguiculata subsp. unguiculata cv. gr. Unguiculata (L.) Walp.), celery
(Apium graveolens L.), common and runner bean (Phaseolus vulgaris L. and P. coccineus
L.) in Italian small holdings (Negri and Tosti 2002; Tosti and Negri 2005; Tiranti and Negri
2007; Mazzucato et al. 2008; Negri et al. 2010). The high intra-specific diversity measured at
sub-population level—between landraces from different holdings—was correlated to
gardeners’ preferences and practices as well as to the small variations in ecological and
agronomic conditions. Similarly high intra-specific diversification was detected among
landraces of Lagenaria siceraria Standl. (Morimoto et al. 2006) in Kenya, mostly due to the
effect of human selection and generations of inbreeding. In the Alta Verapaz region of
Guatemala, the diversity found in populations of Capsicum spp. from home gardens was
comparable to that of samples preserved in the local gene bank, with home garden popu-
lations being richer in rare alleles and infrequent genetic variants (Guzma
`
n et al. 2005). This
point suggests the opportunity of using within-garden conservation of crop and tree genetic
diversity as an effective complementary measure to ex situ strategies.
Cultural and socio-economic features and their relation with plant diversity
The contribution of cultural and socioeconomic factors in generating and maintaining crop
diversity in home gardens has received little attention (Perales and Brush 2005); yet human
Table 2 continued
Country/region Genus or species N. types (landraces or individuals) Source
Lathyrus sativus L. 3
Lens culinaris Medik. 4
Lycopersicon esculentum P. Miller 4
Ocimum basilicum L. 3
Phaseolus vulgaris L. 12
Pisum sativum L. 3
Spinacia oleracea L. 2
Trigonella foenum-graecum L. 2
Triticum spp. 9
Vicia faba L. 18
Vicia sativa L. 6
Wild grasses 8
Zea mays L. 5
Scientific names follow the Index Kewensis (IK)
Biodivers Conserv
123
Table 3 Examples of wild or weedy species found in home gardens
Country/
region
Family Species Use Source
Austria/
Osttirol
Asteracee Taraxacum officinale [Weber] Food (Vogl-Lukasser and
Vogl 2004)
Asteracee Achillea millefolium L. Medicinal
Brassicaceae Capsella bursa-pastoris Medik. Medicinal
Chenopodiaceae Chenopodium bonus-henricus
L.
Food
Hippocastanaceae Billia (Aesculus) Columbiana
L.
Hedge plant
Lamiaceae Mentha arvensis L. ssp.
arvensis
Spice, drink
Malvaceae Malva neglecta Wallr. Medicinal
Papaveraceae Chelidonium majus L. Medicinal
Plantaginaceae Plantago lanceolata L. Medicinal
Urticaceae Urtica dioica L. Food
Verbenaceae Duranta mutisii L.f. Hedge plant
Colombia Bignoniaceae Tecoma mollis L. Hedge plant (Mu
¨
ller et al. 1989)
Cunoniaceae Weinmannia tomentosa L.f. Hedge plant
Gramineae Oplismenus burmannii
P.Beauv.
Soil erosion
control
Gramineae Panicum laxum Sw. Soil erosion
control
Gramineae Panicum trichoides Sw. Soil erosion
control
Moraceae Ficus pandurata Hort. Sand. Shade tree
Piperaceae Peperomia subspathulata
Yunck.
Aromatic
Rosaceae Hesperomeles goudotiana
(Decne.) Killip
Hedge plant
Cuba Bignoniaceae Jacaranda coerulea Auct. Shade tree (Esquivel et al. 1992)
Casuarinaceae Casuarina stricta Miq. Wind break
Compositae Eupatorium ageratifolium DC. Magic plant
Compositae Iva cheiranthifolia Kunth Medicinal
Compositae Spilanthes clava
DC. Spice,
medicinal
Erythroxylceae Erythroxylum longipes
O. E. Schulz
Magic plant
Myrsinaceae Ardisia acuminata Willd. Living fences
Sapindaceae Harpullia arborea Radlk. Shade tree
Guatemala Boraginaceae Cordia dentata Vahl Food, living
fences
(Leiva et al. 2001)
Clethraceae Clethra suaveolens Turcz. Construction
Combretaceae Bucida macrostachya Standl. Timber, fuel
Compositae Neurolaena lobata R.Br. Medicinal
Compositae Vernonia mollis Kunth Fuel
Biodivers Conserv
123
Table 3 continued
Country/
region
Family Species Use Source
Cucurbitaceae Parasicyos Dieterle spp. Soil erosion
control
Melastomataceae Miconia calvescens DC. Religious
Meliaceae Cedrela Mexicana M. Roem. Timber
Myrtaceae Pimenta dioica (L.) Merr. Shade
Ulmaceae Trema micrantha Blume Rope,
construction
Italy/Island
Ustica
Boraginaceae Borago officinalis L. Food (Hammer et al.
1999)
Capparaceae Weedy Capparis spinosa, rupestris
Sibth. et Sm.
Spice
Chenopodiaceae Beta vulgaris subsp. Maritime L. Food
Compositae Cichorium intybus var. glabratum
C.Presl
Food
Compositae Cichorium pumilum Jacq. Food
Compositae Lactuca saligna L. Food
Compositae Lactuca serriola L. Food
Compositae Lactuca virosa L. Food
Lamiaceae Origanum vulgare subsp. viride
Willd. ex Benth.
Spice
Lamiaceae Wild and weedy Rosmarinum
officinalis L.
Spice
Leguminosae Lupinus albus L. Food
Leguminosae Pisum sativum convar. speciousm
L.
Food
Linaceae Linum usitatissimum subsp.
angustifolium Huds.
Fiber
Rutaceae Wild and weedy Ruta chalepensis
L.
Medicinal
Umbrelliferae Weedy Apium graveolens L. Food
Umbrelliferae Wild Daucus carota L. Medicinal
Umbrelliferae Foeniculum vulgare subsp.
piperitum C.Presl
Spice
Mali Anacardiaceae Lannea microcarpa Engl. & Krause Food, dying (Kassogue et al.
1990)
Apocynaceae Saba senegalensis (A.DC.) Pichon Food, medicinal
Rhamnaceae Zizyphus Mauritania Lam. Food, medicinal,
fodder
Sapoteceae Butyrospermum parkii Kotschy Food, medicinal
Nepal Anacardiaceae Spondias pinnata Kurz Fuel wood (Shrestha et al.
2001)
Capparaceae Crateva unilocularis
Burch.-Ham.
Food
Cruciferae Nasturtium officinale L. Food
Biodivers Conserv
123
cultures have profound influence on the diversity of the eco-systems they belong to
(Schneider 2004; Eyzaguirre 2006) and it is often people’s cultural and economic values
which explain differences even among neighbouring fields and gardens.
By spending work and leisure time in home gardens, families and communities turn
them into culturally constructed spaces (Eyzaguirre and Linares 2004) where ethnobo-
tanical knowledge is actively preserved. Customs, traditions and aesthetic preferences
are instrumental in determining the overall aspect of the garden (Birol et al. 2005a;
Smith et al. 2006): different crops or varieties are maintained because of the significance
of each in a family’s traditions or preferences—Italian gardeners insist that one has
a better taste than another or is more suited for preparing a certain time-honoured recipe
(Portis et al. 2004; Sordi et al. 2008)—or because they fulfil aesthetic requirements.
Preference for landraces also resides in their greater adaptation to the specific envi-
ronmental conditions and their capacity to guarantee stable yields also in unfavourable
years or under limiting agronomic conditions (Negri 2003; Andonov and Ivanovska
2004); a landrace’s lack of uniformity itself can be advantageous for household pro-
duction, for example by allowing a longer harvesting season if ripening is prolonged in
time (Negri 2009).
In high income societies, the majority of those involved in gardening activities (Negri
2003; Vogl-Lukasser and Vogl 2004) are elderly household members, who often remain
faithful to landraces they have inherited from prior generations; the average age of gar-
deners recorded in central Italy for instance varies between 58.9 and 70.0 years (Sordi et al.
2008).
Women are often the custodians of seeds and knowledge which they transmit to the
following generation: matrilineal transmission of home garden agro-biodiversity is
reported for potato in the Andean region (Brush 2000), for tomato in southern Italy (Silveri
2007) and for beans in northern Italy (Tonutti 2008). Introduction of and experimentation
with new species in gardens are usually an exclusive task for women and sometimes
children (Maundu 1987; Kassogue et al. 1990; Vogl-Lukasser and Vogl 2004).
The diversified, year-round supply of products from gardens is often crucial for
subsistence among the poorest and most marginalized groups in developing countries.
It can provide important opportunities for small-scale marketing (Miura et al. 2003;
Birol et al. 2005b) while the garden’s physical space itself allows development of other
Table 3 continued
Country/region Family Species Use Source
Liliaceae Aloe barbadensis Mill. Medicinal
Lorantaceae Viscum L. spp. Medicinal
Moraceae Ficus cunia Burch.-Ham. ex Roxb. Fodder
Myrtaceae Eugenia jambolana Lam. Fruit
Phytolaccaceae Phytolacca acinosa Roxb. Food
Rutaceae Xanthoxylum armatum DC. Spice
Rutaceae Aegle marmelos Corre
ˆ
a Religious
Sapotacee Pouteria viridis (Pittier) Cronq. Food
Styracaceae Thysanolaena maxima Kuntze Forage
Urticaceae Boehmeria rugulosa Wedd. Fuel wood
Scientific names follow the Index Kewensis (IK)
Biodivers Conserv
123
Table 4 Measures of diversity for single crops grown in home gardens in different countries. More than one landrace is grown in single home gardens (home garden landrace
richness is always greater than 1) and community-level richness indicates that communities harbour a large number of landraces (from Jarvis 2008)
Breeding
system
(Cl = 1;
In = 2,
Po = 3,
Out = 4)
Use
(staple = 1;
non-
staple = 2)
Crop Country Community Tot. crop area
in community
(ha)
No. of
modern
vars
Proportion of
HGs growing
landraces
No.
sampled
HGs
Area of
Traditional
vars/HG (m
2
)
HG
landrace
richness
HG
evenness
(Simpson)
Community
richness
Community
evenness
Divergence
(between/
total%)
2 2 Bean Hungary De
´
vava
´
nya 3 2 40 36 15.2 1.6 0.28 12 0.85 0.67
2 2 Bean Hungary
}
Orse
´
g
4 3 64 58 17.28 1.4 0.17 13 0.77 0.78
2 2 Bean Hungary Szatma
´
r-
Bereg
12 3 81 74 48.6 1.8 0.16 20 0.55 0.71
2 2 Beans Peru Aguaytia
Valley
390 1 97 31 2813 1.12 0.06 3.01 0.32 0.81
2 2 Beans Peru Ucayali
Valley
312 0 100 36 2800 1.19 0.08 4 0.26 0.71
2 2 Beans Peru Pichis-
Pachitea
Valley
160 0 100 16 3400 1.31 0.13 3 0.28 0.52
2 2 Finger
millet
Nepal Bara 8 0 100 18 420 1.06 0.03 6 0.75 0.96
2 2 Finger
millet
Nepal Kaski 200 0 100 146 2000 1.72 0.26 24 0.68 0.62
HG home garden; vars varieties; Cl clonal; In inbreeding; Po partially outcrossing; Oc outcrossing
Biodivers Conserv
123
income-generating activities such as handicraft production or blacksmithing (Mitchell and
Hanstad 2004).
Households’ socio-economic status and patterns are often reflected in the genetic
diversity of garden crops and plants, although the exact nature of the relationship is highly
variable. Significant correlation between household income and species richness indices
has been proven in China (Yongneng et al. 2006). In Nepal poor households facing more
restricted access to land manage less agro-biodiversity than relatively better off households
(Adhikari et al. 2004), confirming the idea that farmers with less rights on the land are less
willing to make long term investments and the diversity they maintain is likely to be lower
(Arnold 1987). In Eastern Europe’s transition economies, as infrastructures and market
access develop and off-farm employment opportunities increase, people tend to rely less on
their own produce and gardens’ composition and diversity are gradually simplified, with
a predominance of perennials, ornamentals and low-maintenance species (Birol et al.
2005a). Nevertheless, development of niche markets may reverse this trend and revitalize
cultivation of traditional crops or varieties, which may be commercialized as traditional
specialties and provide income opportunities to gardeners (Vasey 1985; Hoogerbrugge and
Fresco 1993; Marsh 1998; Sordi et al. 2008; Polegri and Negri 2010). More frequently
though, garden crops are maintained in cultivation because of personal affection and
commitment of single gardeners, resulting in maintenance of a greater portion of intra-
specific diversity than a market exposure permits. Indeed, on any market, consumers’
request for uniformity or competition with cheaper commercial varieties determines some
extent of standardization in the crop populations and a decrease of intra-specific and intra-
varietal diversity, as described for Sechium edule Sw. in Guatemala and for ‘‘Cuneo’’
pepper (Capsicum annuum L.) and other crops (Azurdia et al. 2001; Bravi et al. 2002;
Portis et al. 2004) in Italy.
Factors affecting the conservation of biodiversity in home gardens
In determining how home gardens can best contribute to conservation of agro-biodiversity,
all factors affecting its distribution within and across gardens, its evolution and resilience
over time need to be understood. For such purpose, one of the urgent issues facing research
on garden-based conservation is the definition of the minimum size of conservation units
which are needed to conserve viable populations of the target species. Once established,
these conservation units can be used to monitor evolutionary changes in the genetic
diversity they harbour, for example, by using molecular markers for measures of drift,
selection and gene-flow. Such information is crucial to ensure long-term conservation of
any crop (Tosti and Negri 2005; Tiranti and Negri 2007) as well as of the many associated
wild species (Goddard et al. 2009).
A home garden will seldom host more than a few hundred plants (indeed, most often it
will contain only a few individuals) even of the most important crops (Hodgkin 2001) and
the population size is highly variable depending on the species. Because of such variation
in terms of inter- and intra-specific diversity, scientists generally agree that a representative
conservation unit should include not one but a number of gardens in multiple agro-
ecological zones, thus capturing a significant representation of the overall diversity for any
given species (Brown and Marshall 1995). In planning conservation measures, the genetic
structure of home garden populations, particularly of crop landraces, should be taken into
account. Landraces in a given area often consist of a series of sub-populations distributed
across a number of gardens. Each subset interacts with others and this interaction
Biodivers Conserv
123
contributes to shaping the overall diversity of the landrace (Louette 2000; Tosti and Negri
2005; Tiranti and Negri 2007; Negri et al. 2010). These small-scale evolutionary processes
are influenced both by natural (breeding systems, pollination mechanisms, mutation rates)
and human factors such as introduction or displacement of varieties (Brush 2004), selection
and seed exchange.
Selection is possibly the factor that most profoundly influences the evolution of agro-
biodiversity, hence its conservation, due to its effects on population structure (Brush 2004).
Farmers’ selection is a dynamic practice which depends on many variables such as the
fields’ size, the crop, the market’s demand and may easily change depending on oppor-
tunities: farmers in Mexico seek to maintain certain traits of their maize landraces because
of traditional preferences (Louette and Smale 2000), whereas immigrants’ in Germany
select for novel traits which will adapt their native crops to the colder growing conditions
(Gladis 2001). On the small scale of the home garden, the extent and the effect of selection
are not fully understood. Nevertheless, the examples above suggest that it will not be
necessarily aimed at obtaining near identical genotypes, as occurs within breeding pro-
grammes of industrial seed producers. Seed movement and gene-flow add up to the effects
of selection in modifying garden crop diversity. More divergence may exist between
neighbouring home gardens whose owners do not exchange germplasm than between more
distant home gardens whose owners share their seeds (Guarino and Hoogendijk 2004).
Gene-flow involving wild relatives, landraces and modern varieties is facilitated by the
limited spatial separation of individuals grown in gardens. Gradual introduction of novel
variation from wild to domesticated forms of Beta (Hammer et al. 1986), Brassica (Perrino
and Hammer 1985) and Pyrus (Hammer et al. 1986) has been observed in gardens of
southern Italy.
The future of garden-based conservation and research
Changes occurring under increasing demographic and economic pressures fuel concern for
the future of traditional home gardens and the genetic reservoir they contain. The global
trend toward large-scale agriculture determines a gradual simplification of the agricultural
systems and landscapes in which crops are produced and an erosion of the sophisticated
knowledge associated to farming practices (Anderson 1993; Birol et al. 2005a).
Replacement of rural areas once used for the production of services (home gardens,
wooded areas, living fences, pastures) by monocultures has caused a depletion of local
species, primitive varieties and wild relatives (Negri 2005). Studies of species richness in
home gardens in Rupandehi and Gulmi in Western Nepal over 10–15 years recorded the
disappearance of as many as 20 crop species and declared another 11 under threat of
extinction, mainly because of changes in land use patterns and inaccessibility of local seed
(Sunwar et al. 2006). Already in the nineties, genetic erosion in landraces of garden and
small-farm crops was measured as 72.4% in Albania (between collecting missions of 1941
and 1993) and 72.8% (between 1950 and 1980) in southern Italy (Hammer et al. 1996).
‘‘Modern’’ varieties which replace local landraces in large scale industrialized agri-
culture represent undeniable advances in breeding, offering higher yields under intensive
growing conditions with optimal availability of water and other inputs. But in many
agricultural contexts where such conditions are not met, for geographical or technical
reasons, they still perform poorly compared to adapted landraces (Ceccarelli 1996). The
latter, if they are retained at all, survive in low numbers in family farms and home gardens
and there is concern that their potential is not fully realised (Newton et al. 2010).
Biodivers Conserv
123
Nevertheless, there are newly emerging positive trends in home gardening, which
encourage people to maintain biodiversity in rural or urban gardens. In developing
countries, the nutritional value of local, neglected horticultural species has been assessed
and their cultivation in family gardens promoted to guarantee the intake of vitamins and
micro-nutrients (Odhav et al. 2007) aiding in the control of HIV infections and other
diseases (Callens and Gallagher 2003). Establishment of food producing gardens, often
based on local seed systems and traditional crops, in areas of explosive urbanization is
becoming an important tool for making cities more sustainable while also providing
marginal sectors of the population with working opportunities, healthier food and rein-
forcing their cultural identity (Van Veenhuizen 2006; Seck 2009).
In high-income countries the growing demand for healthier lifestyles and closer con-
nection with nature has driven a renewed interest towards sustainable agricultural systems
and ‘‘traditional’’ food products, capable of connecting consumers to the natural and
cultural heritage of a community or a geographical region. Founded in Italy, the now
world-renowned Slow Food movement is fostering a growing social and cultural awareness
that actively promotes local, traditional foods based on local agro-biodiversity resources
and produced by small-scale farming communities. In Italy, regional governing bodies
have set up subsidies to encourage the cultivation of landraces among networks of ‘‘cus-
todians’’ who have preserved them so far, often in their home gardens. In other cases, local
landraces still found in home gardens have been granted official protection through
inclusion of their products in the list of specialties of the region, as was the case for the
Italian ‘‘Fagiolina’’ bean, Vigna unguiculata (Sordi et al. 2008; Negri 2009; Polegri and
Negri 2010). Many urban citizens of the developed world have taken up some form of self-
production of food in their terraces, roofs, gardens or courtyards as well as in communal
areas shared among neighbours (Bhatt and Farah 2009; Bradley 2009). In various coun-
tries, municipalities (or other institutions such as The National Trust in the UK) assign
unused public urban space to the local population or to specific groups, most often pen-
sioners (Tei et al. 2009) or school children. Associations and NGOs play a leading role in
promoting garden agro-biodiversity by carrying out general educational activities or
actively supporting cultivation and exchange of heirloom varieties (see Table 5 for an
overview). The UK-based charity Garden Organic, with its Heritage Seed Library, coor-
dinates a number of volunteer ‘‘seed guardians’’, who contribute to the reproduction,
conservation and exchange of seeds from heirloom varieties.
Grassroots organizations are increasingly involved in political processes and decisions
affecting the survival of small-scale agricultural systems and their biodiversity, to an extent
that they have been instrumental in fuelling changes in European regulations and Inter-
national agreements on agricultural genetic resources. In response to long-lasting pressures
from this ‘‘informal’’ sector, the EU recently established a separate regulation system for
seed production and marketing of ‘‘conservation varieties’’ (EC 2008). Traditional crops
and local varieties selected and reproduced in small farms and gardens were formerly
excluded from commercialization because of their lack of distinctiveness, uniformity and
stability. The recent change in EU regulations legalized exchange and marketing of
‘‘traditional’’ seed and this may reduce the risk of genetic erosion, offering greater chances
for the survival of agro-biodiversity and of the small-scale production systems which
sustain it.
In 2007 a workshop organized by the On-farm Conservation Task Force of the Euro-
pean Cooperative Program on Plant Genetic Resources (ECPGR) brought together rep-
resentatives from different sectors—scientists, extension agents, members of farmers’
groups, NGOs, associations—to discuss new avenues for home garden research and
Biodivers Conserv
123
conservation in Europe and to foster greater inter-sectoral collaboration on home garden
issues beyond the borders of developing countries. Participants agreed on the opportunity
and importance of clearly defining home gardens’ role in conservation of crop genetic
diversity by gathering more comprehensive and cross-country evidence. The experts rec-
ommended special attention be directed to some key issues, among which home gardens’
composition and patterns of intra-specific genetic diversity, particularly for landraces and
underutilized species; the stability of such diversity and its ability to respond to climate
variations and changing trends in agricultural and social models; the action and impact of
selection, drift and gene flow on the evolution and resilience of gardens’ diversity; the
extent to which the impact of these evolutionary forces in the complex garden micro-
environment is different from their effects on larger populations of other agro-ecosystems;
the indissoluble link between agro-biodiversity and cultural heritage.
Exploring the conservation potential of the many diversified home garden systems
discloses opportunities for interdisciplinary studies involving botanists, ecologists, genet-
icists, anthropologists, and sociologists. An improved understanding of the factors which
encourage or enable diversity within the domain of home gardens would allow conser-
vation scientists and communities to foster and maintain important knowledge and
Table 5 A list of institutions, NGOs, Associations or farmers’ groups actively involved in conservation
of agricultural genetic resources through small-scale farming or gardening
Country Organization Website/Email address
Austria Arche Noah www.arche-noah.at
Australia Seed Savers www.seedsavers.net/
Canada Seeds of diversity www.seeds.ca/en.php
France Kokopelli www.kokopelli.it
Re
´
seau Semences Paysannes/BEDE www.semencespaysannes.org
Georgia Elkana Biological Farming Association www.elkana.org.ge
Germany IG fur Gentechnikfreie Saatgutarbeit http://www.gentechnikfreie-saat.de/
Save Our Seeds www.saveourseeds.org
Ven http://www.nutzpflanzenvielfalt.de/
VERN http://www.vern.de/
Hungary Ormansag Foundation ormansag@axelero.hu
Protect the Future (HU)/Re
´
seau http://www.vedegylet.hu
Italy Consorzio della Fagiolina del Trasimeno www.fagiolina.com
Consorzio della Quarantina www.quarantina.it
Abruzzo Region http://www.arssa.abruzzo.it
Lazio Region http://www.arsial.regione.lazio.it
Toscana Region http://germoplasma.arsia.toscana.it
Rete Semi Rurali/AIAB www.semirurali.net
Portugal Colher Para Semear gcalderaribeiro@gmail.com
Spain Red de Semillas/Red Andaluza de Semillas www.redandaluzadesemillas.org/
Switzerland Pro Specie Rara www.prospecierara.ch
UK HDRA_The Heritage Seed Library www.gardenorganic.org.uk/hsl
USA International Seed Saving Institute www.seedsave.org/issi/issi.html
Seed Savers Exchange www.seedsavers.org/
International Slow Food Foundation for Biodiversity www.slowfoodfoundation.com
Biodivers Conserv
123
biological resources while also preserving the wealth of services these multifunctional,
sustainable agro-ecosystems provide to nature and people.
References
Adhikari A, Singh D, Suwal R et al. (2004) The role of gender in the home garden management and benefit-
sharing from home gardens in different production system of Nepal. In: Gautam R, B. Sthapit, and
Shrestha P (eds) Proceedings of workshop ‘‘Enhancing the contribution of home garden to on-farm
management of plant genetic resources and to improve the livelihoods of Nepalese farmers: lessons
learned and policy implications’’. Bioversity international and Swiss agency for development and
cooperation (SDC), pp 84–98
Altieri MA, Merrick LC (1987) In situ conservation of crop genetic resources through maintenance of
traditional farming systems. Econ Bot 41:86–96
Anderson EN (1993) Gardens in tropical America and tropical Asia. Bio
`
tica Nueva Epoca 1:81–102
Andonov S, Ivanovska S (2004) Let’s protect agrobiodiversity. Ministry of Environment and Physical
Planning, Skopje, Macedonia
Arnold JEM (1987) Economic considerations in agroforestry. In: Steppler HA, Nair PKR (eds) Agrofor-
estry: a decade of development. International council for eesearch in agroforestry (ICRAF), Nairobi,
Kenya, pp 173–190
Azurdia C, Leiva M, Ayala H et al (2001) Contribution of home gardens to in situ conservation of plant
genetic resources II. Alta Verapaz case. Working document. IPGRI-USAC, Rome, Italy
Bennett-Lartey SO, Markwei C, Ayernor GS et al. (2001) Contribution of home gardens to in situ con-
servation resources in farming systems in Ghana. A report of home garden surveys in Ghana. In:
Watson JW, and Eyzaguirre PB (eds) Proceedings of the second international home garden workshop.
Bioversity international, Rome, Italy, pp 83–96
Bhatt V, Farah L (2009) Urban design for food-security: thinking globally designing locally. In: Proceedings
of the second international conference on landscape and urban horticulture. Department of agroen-
vironmental science and technology (DiSTA), Faculty of agriculture, University of Bologna, Italy, p 40
Birol E, Bela G, Smale M (2005a) The role of home gardens in promoting multi-functional agriculture in
Hungary. EuroChoices 3:14–21
Birol E, Kontoleon A, Smale M (2005b) Farmer demand for agricultural biodiversity in Hungary’s transition
economy: a choice experiment approach. In: Smale M (ed) Valuing crop biodiversity–on farm genetic
resources and economic change. CABI publishing, Wallingford, UK, pp 119–143
Bradley L (2009) Community gardening: food production in the neighborhood. In: Proceedings of the
second international conference on landscape and Urban horticulture. Department of agroenviron-
mental science and technology (DiSTA), Faculty of agriculture, University of Bologna, Italy, p 39
Bravi R, Negri V, Porfiri O (2002) La salvaguardia della biodiversita
`
e la produzione delle sementi di specie
ortive. Sementi Elette 4:25–29
Brown AHD, Marshall DR (1995) A basic sampling strategy: theory and practice in collecting plant genetic
diversity technical guidelines. CABI publishing, Wallingford, UK, pp 75–91
Brush S (2000) Ethnoecology, biodiversity and modernization in Andean potato agriculture. In: Minnis P
(ed) Ethnobotany a reader. University of Oklahoma Press, Oklahoma, pp 283–306
Brush S (2004) Farmers’ bounty locating crop diversity in the contemporary world. Yale University Press,
New Haven, Connecticut
Brush S, Taylor E, Bellon M (1992) Technology adoption and biological diversity in Andean potato
agriculture. J Dev Econ 39:365–387
Callens K, Gallagher KD (2003) Incorporating nutrition in farmer field schools food, nutrition and agri-
culture. Food and agriculture organization of the United Nations, Rome, Italy
Castin
˜
eiras L, Guzma
`
n FA, Duque MC et al (2007) AFLPs and morphological diversity of Phaseolus
lunatus L in Cuban home gardens: approaches to recovering the lost ex situ collection. Biodivers
Conserv 16:2847–2865
CBD (1992) Convention on Biological Diversity. Secretariat of the convention on biological diversity,
United Nations environment program. Available at www.biodiv.org/convention/articles.asp
Ceccarelli S (1996) Specific adaptation and breeding for marginal conditions. Euphytica 77:205–219
Coomes OT, Ban N (2004) Cultivated plant species diversity in home gardens of an Amazonian peasant
village in northeastern Peru. Econ Bot 58:420–434
Daniels GD, Kirkpatrick JB (2006) Does variation in garden characteristics influence the conservation
of birds in suburbia? Biol Conserv 133:326–335
Biodivers Conserv
123
Das T, Das AK (2005) Inventorying plant biodiversity in homegardens: a case study in Barak Valley,
Assam, North East India. Curr Sci 89:155–163
EC (2008) Commission Directive 2008/62/EC (20 June 2008) Official Journal of the European Union,
L 162/13
Engels J (2001) Home gardens–a genetic resource perspective. In: Watson JW, Eyzaguirre PB (eds) Pro-
ceedings of the second international home garden workshop. Bioversity international, Rome, Italy,
pp 3–9
Esquivel M, Knuepffer H, Hammer K (1992) Chapter 14. Inventory of the cultivated plants In: Hammer K,
Esquivel M, Knuepffer H (eds) Origin, evolution and diversity of Cuban plant genetic resources,
Gatersleben, Germany, pp 213–454
Eyzaguirre P (2006) Agricultural biodiversity and how human culture is shaping it. In: Cernea M, Kassam A
(eds) Researching the culture in agri-culture. CABI, Wallingford, UK, pp 264–284
Eyzaguirre P, Linares O (2004) Introduction. In: Eyzaguirre P, Linares O (eds) Home gardens and agro-
biodiversity. Smithsonian Books, Washington, pp 1–28
Eyzaguirre P, Watson J (2001) Home gardens and agrobiodiversity: an overview across regions. In:
Watson JW, Eyzaguirre PB (eds) Proceedings of the second international home garden workshop.
Bioversity international, Rome, Italy, pp 10–13
Feuillet C, Langridge P, Waugh R (2008) Cereal breeding takes a walk on the wild side. Trends Genet
24:24–32
Gaston KJ, Warren PH, Thompson K et al (2005) Urban domestic gardens (IV): the extent of the resource
and its associated features. Biodivers Conserv 14:3327–3349
Gladis T (2001) The neglected diversity of immigrant gardens in Germany—examples from Bonn. In:
Proceedings of the second international home garden workshop. Bioversity international, Rome, Italy
Gliessman SR (1990a) Integrating trees into agriculture: the home garden agro-ecosystem as an example of
agro-forestry in the tropics. In: Gliessman SR (ed) Agroecology: researching the ecological basis for
sustainable agriculture. Springer-Verlag, New York, pp 160–168
Gliessman SR (1990b) Understanding the basis for sustainability for agriculture in the tropics: experiences
in Latin America. In: Edwards CA, Lal R, Madden P, Miller RH, House G (eds) Sustainable agri-
cultural systems. St. Lucie Press, Delray Beach, Florida, pp 378–390
Goddard MA, Dougill AJ, Benton TG (2009) Scaling up from gardens: biodiversity conservation in urban
environments. Trends Ecol Evol 25:90–98
GSPC (2002) Global strategy for plant conservation. Secretariat of the convention on biological diversity,
United Nations environment program. Available at http://www.cbd.int/gspc/strategy.shtml
Guarino L, Hoogendijk M (2004) Microenvironments. In: Eyzaguirre P, Linares O (eds) Home gardens and
agrobiodiversity. Smithsonian Books, Washington, pp 31–40
Guijt I, Hinchcliffe F, Menyk M (1995) The hidden harvest: the value of wild resources in agricultural
systems—a summary. International institute for environment and development (IIED). London (UK)
Guzma
`
n FA, Ayala H, Azurdia C et al (2005) AFLP assessment of genetic diversity of Capsicum genetic
resources in Guatemala: home gardens as an option for conservation. Crop Sci Soc Am 45:363–370
Hammer K, Cifarelli S, Perrino P (1986) Collection of land-races of cultivated plants in South Italy, 1985.
Kulturpflanze 34:261–273
Hammer K, Knu
¨
pffer H, Xhuveli L et al (1996) Estimating genetic erosion in landraces—two case studies.
Genet Resour Crop Evol 43:329–336
Hammer K, Laghetti G, Perrino P (1997) Proposal to make the island of Linosa/Italy as a centre for on-farm
conservation of plant genetic resources. Genet Resour Crop Evol 44:127–135
Hammer K, Laghetti G, Perrino P (1999) A checklist of the cultivated plants of Ustica (Italy). Genet Resour
Crop Evol 46:95–106
Hammer K, Arrowsmith N, Gladis T (2004) Agrobiodiversity with emphasis on plant genetic resources.
Naturwissenschaften 90:241–250
High C, Shackleton CM (2000) The comparative value of wild and domestic plants in home gardens of a
South African rural village. Agrofor Syst 48:141–156
Hodgkin T (2001) Home gardens and the maintenance of genetic diversity. In: Watson JW, Eyzaguirre PB
(eds) Proceedings of the second international home garden workshop. Bioversity international, Rome,
Italy, pp 14–18
Hoogerbrugge ID, Fresco LO (1993) Homegarden systems: agricultural characteristics and challenges
gatekeeper Series no. 39. International institute for environment and development, London, UK
Hughes CE, Govindarajulu R, Robertson A et al (2007) Serendipitous backyard hybridization and the origin
of crops. Proc Natl Acad Sci 104:14389–14394
IPGRI (1993) Diversity for development: the strategy of the international plant genetic resources institute.
International plant genetic resource institute, Rome, Italy
Biodivers Conserv
123
ITPGRFA (2001) International treaty on plant genetic resources for food and agriculture. Food and agri-
culture organization of the United Nations, Rome, Italy
Juma C (1989) Biological diversity and innovation: conserving and utilizing genetic resources in Kenya.
African centre for technology studies, Nairobi, Kenya
Kassogue A, Dolo J, Ponsioen T (1990) Traditional soil and water conservation in the Dogon plateau Mali.
Dryland networks programme, Paper no. 23, London, IIED
Kulpa W, Hanelt P (1981) Activities regarding collection and evaluation of Polish landraces. Kulturpflanze
29:81–90
Laghetti G, Miceli F, Cifarelli S et al (2004) Collection of crop genetic resources in Italy. Plant Genet
Resour Newsl 152:82–87
Le Coeur D, Baudry J, Burel F et al (2002) Why and how we should study field boundary biodiversity in an
agrarian landscape. Agric Ecosyst Environ 89:23–40
Leiva JM, Azurdia C, Ovando W et al. (2001) Contributions of home gardens to in situ conservation in
traditional farming systems—Guatemalan component. In: Watson JW, and Eyzaguirre PB (eds)
Proceedings of the second international home gardens workshop. Bioversity international, Rome, Italy,
pp 56–72
Linares OF (1996) Cultivating biological and cultural diversity: urban farming in Casamance, Senegal.
Africa 66:104–121
Louette D (2000) Traditional management of seed and genetic diversity: what is a landrace? In: Brush SB
(ed) Genes in the field. IPGRI, Rome/IDRC. Ottawa/Lewis publishers, Boca Raton, Florida,
pp 109–142
Louette D, Smale M (2000) Farmers’ seed selection practices and traditional maize varieties in Cuzalapa,
Mexico. Euphytica 113:25–41
Marsh R (1998) Building on traditional gardening to improve household food security food, nutrition and
agriculture No. 22. Food and agriculture organization of the United Nations, Rome, Italy
Marshall EJP, Moonen AC (2002) Field margins in northern Europe: their functions and interactions with
agriculture. Agric Ecosyst Environ 89:5–21
Maundu P (1987) The importance of gathered fruits and medicinal plants in Kakyuni and Kathama areas of
Machakos. In: Wachiira KK (ed) Women’s use of off-farm and boundary lands: agroforestry poten-
tials. International Centre of Research in Agroforestry (ICRAF), Nairobi, pp 56–60
Mazzucato A, Papa R, Bitocchi E et al (2008) Genetic diversity structure and marker-trait associations
in a collection of tomato (Solanum lycopersicum L.) Italian landraces. Theor Appl Genet 116:657–669
Mitchell R, Hanstad T (2004) Small homegarden plots and sustainable livelihoods for the poor. LSP
Working paper no.11. Food and agriculture organization of the United Nations, Rome, Italy
Miura S, Osamu K, Susumu W (2003) Home gardening in urban poor communities of the Philippines. Int
J Food Sci Nutr 54:77–88
Morimoto Y, Maundu P, Kawase M et al (2006) RAPD polymorphism of the White-Flowered gourd
(Lagenaria siceraria (Molina) Standl.) landraces and its wild relatives in Kenya. Genet Resour Crop
Evol 53:963–974
Mu
¨
ller GK, Bohorquez A, Quintero O et al (1989) Bericht u
¨
ber eine Reise in Kolumbien 1988 Zur
Sammlung pflanzlicher genetischer Ressourcen. Kulturpflanze 37:373–390
Negri V (2003) Landraces in central Italy: where and why they are conserved and perspectives for their on-
farm conservation. Genet Resour Crop Evol 50:871–885
Negri V (2005) Agrobiodiversity conservation in Europe: ethical issues. J Agric Environ Ethics 18:3–25
Negri V (2009) Possible incentives to home garden maintenance: comparing possibilities and raising
awareness among farmers. In: Proceedings of a workshop on crop genetic resources in European home
gardens. Bioversity international, Rome, Italy, pp 72–80
Negri V, Polegri L (2009) Genetic diversity in home gardens in Umbria a cowpea case study. In:
Proceedings of a workshop on crop genetic resources in European home gardens. Bioversity inter-
national, Rome, Italy, pp 55–61
Negri V, Tosti N (2002) Phaseolus genetic diversity maintained on-farm in central Italy. Genet Resour Crop
Evol 49:511–520
Negri V, Maxted N, Vetelainen M (2009) European landrace conservation: an introduction. In: Vetelainen
M, Negri V, Maxted N (eds) Technical Bullettin n. X. European landraces: On-farm conservation,
management and use. Bioversity international, Rome, Italy
Negri V, Castellini G, Tiranti B et al. (2010) Landraces are structured populations and should be maintained
on farm. In: Proceedings of the 18th Eucarpia genetic resources section meeting, in press
Newton AC, Akar T, Baresel JP et al (2010) Cereal landraces for sustainable agriculture. A review. Agron
Sustain Dev 30:237–269
Biodivers Conserv
123
Nin
˜
ez VK (1984) Household gardens: theoretical considerations on an old survival strategy. Report No. 1
Potatoes in food systems research series. International potato research centre
Nowosielka D, Podyma W (2001) Collection missions in the territory of Poland during 1998–1999. In:
Swiecicki W, Naganowska B, Wolko B (eds) Proceedings of the Eucarpia genetic resources section
meeting: broad variation and precise characterisation. Bioversity international, Rome, Italy, pp 67–70
Nunney L, Campbell KA (1993) Assessing minimum viable population size: demography meets population
genetics. Trends Ecol Evol 8:234–239
Odhav B, Beekrum S, Akula U et al (2007) Preliminary assessment of nutritional value of traditional leafy
vegetables in KwaZulu-Natal, South Africa. J Food Comp Anal 20:430–435
Paoletti M (2001) Biodiversity in agroecosystems and bioindicators of environmental health. In: Shiyomi M,
Koizumi H (eds) Structure and function in agroecosystems design and management advances in
agroecology. CRC press, Boca Raton, Florida, pp 11–44
Pavia R, Barbagiovanni I, Strada GD et al. (2009) Autochthonous fruit tree germplasm at risk of genetic
erosion found in home gardens in the region of Latium (Italy). In: Proceedings of a workshop on crop
genetic resources in European home gardens. Bioversity international, Rome, Italy
Perales HR, Brush SB (2005) Maize diversity and ethnolinguistic diversity in Chiapas, Mexico. Proc Natl
Acad Sci 102:949–954
Perrino P, Hammer K (1985) Collection of landraces of cultivated plants in South Italy 1984. Kulturpflanze
31:227–279
Polegri L, Negri V (2010) Molecular markers for promoting agro-biodiversity conservation: a case study
from Italy. How cowpea landraces were saved from extinction. Genet Resour Crop Evol 57:867–880
Portis E, Acquadro A, Comino C et al (2004) Effect of farmers’ seed selection on genetic variation of
a landrace population of pepper (Capsicum annuum L.) grown in North-West Italy. Genet Resour Crop
Evol 51:581–590
Quiroz C, Gutie
´
rrez M, Rodrı
´
guez D et al. (2001) Home gardens and in situ conservation of agrobiodi-
versity—Venezuelan component. In: Watson JW, and Eyzaguirre PB (eds) Proceedings of the second
international home garden workshop. Bioversity international, Rome, Italy
Schneider J (2004) Toward an analysis of home garden cultures. On the use of sociocultural variables in
home garden studies. In: Eyzaguirre PB, Linares O (eds) Home gardens and agrobiodiversity.
Smithsonian books, Washington, pp 41–55
Seck M (2009) Io mangio Wolof. SlowFood 43:42–44
Seeth HT, Chachnov S, Surinov A (1998) Russian poverty: muddling through economic transition with
garden plots. World Dev 26:1611–1623
Shrestha P, Gautam R, Rana RB et al (2001) Home gardens in Nepal: status and scope for research and
development. In: Watson JW, Eyzaguirre PB (eds) Proceedings of the second international home
garden workshop. Bioversity international, Rome, Italy, pp 105–118
Silveri D (2007) Regional Government of Abruzzo Region, Italy. Personal communication
Smith RM, Thompson K, Hodgson JG et al (2006) Urban domestic gardens (IX): composition and richness
of the vascular plant flora, and implications for native biodiversity. Biol Conserv 129:312–322
Soemarwoto O, Soemarwoto I, Karyono et al. (1975) The Javanese home garden as an integrated ecosystem.
Proceedings of an International congress on the human environment. Science council of Japan, Kyoto,
Japan: 193-197
Sommers P (1978) Traditional home gardens of selected Philippine households and their potential for
improving human nutrition. Master thesis. University of the Philippines, Los Banos, The Philippines
Sordi M, Polegri L, Negri V (2008) Biodiversita
`
di interesse agrario nel comprensorio del Lago Trasimeno.
University of Perugia/Trasimeno Lake Regional park, Italy. ISBN: 88-87652-13-9-978-88-87652-13-
0-3736-203987, also available at http://www.agr.unipg.it/dbvba/biodiversitatrasimeno.pdf
Soule
´
ME (1987) Viable Populations for Conservation. Cambridge University press, Cambridge, UK
Stoler A (1975) Garden use and household consumption pattern in a Javanese village PhD thesis. Depart-
ment of anthropology, Columbia University, New York
Sunwar S, Thornstro
¨
m CG, Subedi A et al (2006) Home gardens in western Nepal: opportunities and
challenges for on-farm management of agrobiodiversity. J Biodiver Conserv 15:4211–4238
Tanksley SD, McCouch SR (1997) Seed banks and molecular maps: unlocking genetic potential from the
wild. Science 277:1063–1066
Tei F, Benincasa P, Farneselli M et al. (2009) Allotment gardens for senior citizens in Italy: current status
and technical proposals. Proceedings of the second international conference on landscape and urban
horticulture. Department of agroenvironmental science and technology (DiSTA), Faculty of agricul-
ture, University of Bologna, Italy: 41
Tilman D (1999) Global environmental impacts of agricultural expansion: the need for sustainable and
efficient practices. Proc Natl Acad Sci 96:1857–1861
Biodivers Conserv
123
Tilman D (2000) Causes, consequences and ethics of biodiversity. Nature 405:208–211
Tiranti B, Negri V (2007) Selective micro-environmental effects play a role in shaping genetic diversity and
structure in a Phaseolus vulgaris L. landrace: implications for on-farm conservation. Molecular
Ecology 16:4942–4955
Tonutti S (2008) Vecchie varieta
`
: tradizione, passione e cura. In: Miceli F, Costantini E (eds) La biodiversita
`
coltivata, Storie di persone, piante e agricoltura tradizionale tra Friuli e Carinzia. Editrice Universitaria
Udinese, Udine, Italy, pp 153–163
Tosti N, Negri V (2005) On-going on-farm microevolutionary processes in neighbouring cowpea landraces
revealed by molecular markers. Theor Appl Genet 110:1275–1283
Trinh LN, Hue NN, De NN et al (2001) Role of home gardens in the conservation of plant genetic resources
in Vietnam. In: Watson JW, Eyzaguirre PB (eds) Proceedings of the second international home garden
workshop. Bioversity international, Rome, Italy, pp 97–104
Van Veenhuizen R (2006) Introduction. In: Van Veenhuizen R (ed) Cities farming for the future—urban
agriculture for green and productive cities. RUAF Foundation, International development research
centre (IDRC) and international institute of rural reconstruction (IIRR), The Philippines, pp 1–17
Vasey DE (1985) Household gardens and their niche in Port Moresby, Papua New Guinea. Food Nut
Bulletin 7:37–47
Viljoen A, Bohn K, Tomkins M et al. (2009) Places for people, places for plants: evolving thoughts on
continuous productive urban landscapes. Proceedings of the second international conference on
landscape and urban horticulture. Department of agroenvironmental science and technology (DiSTA),
Faculty of agriculture, University of Bologna, Italy: 38
Vogl-Lukasser B, Vogl C (2004) Ethnobotanical research in homegardens of small farmers in the alpine
region of Osttirol (Austria): an example for bridges built and building bridges. Ethnobotany Res Appl
2:111–137
Yongneng F, Huijun G, Aiguo C et al (2006) Household differentiation and on-farm conservation of
biodiversity by indigenous households in Xishuangbanna, China. Biodivers Conserv 15:2687–2703
Biodivers Conserv
123