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Urban agriculture is not a relict of the past that will fade away (urban agriculture increases when
the city grows) nor brought to the city by rural immigrants that will loose their rural habits over time. It
is an integral part of the urban system.In each city a further specification of urban agriculture is possible
by looking at the following dimensions:
TYPES OF ACTORS INVOLVED IN URBAN AGRICULTURE
Large part of the people involved in urban agriculture is the urban poor. Contrary to general
belief they are often not recent immigrants from rural areas (since the urban farmer needs time to get
access to urban land, water and other productive resources). In many cities, one will often also find
Lower And Mid-Level government officials, school teachers and the like involved in agriculture, as
well as richer people who are seeking a good investment for their capital.
Women constitute an important part of urban farmers, since agriculture and related processing and
selling activities, among others, can often be more easily combined with their other tasks in the
household. It is however more difficult to combine it with urban jobs that require travelling to the town
centre, industrial areas or to the houses of the rich.
TYPES OF LOCATION IN URBAN AGRICULTURE
Urban agriculture may take place in locations inside the cities (intra-urban) or in the peri-
urban areas. The activities may take place on the homestead (on-plot) or on land away from theresidence (off-plot), on private land (owned, leased) or on public land (parks, conservation areas, along
roads, streams and railways), or semi-public land (schoolyards, grounds of schools and hospitals).
TYPES OF PRODUCTS GROWN IN URBAN AGRICULTURE
Urban agriculture includes food products, from different types of crops (grains, root crops,
vegetables, mushrooms, fruits) and animals (poultry, rabbits, goats, sheep, cattle, pigs, guinea pigs, fish,
etc.) as well as non-food products (like aromatic and medicinal herbs, ornamental plants, tree products,
etc.) or combinations of these. Often the more perishable and relatively high-valued vegetables and
animal products and by-products are favored.
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Production units in urban agriculture in general tend to be more specialized than rural enterprises, and
exchanges are taking place across production units.
TYPES OF ECONOMIC ACTIVITIES IN URBAN AGRICULTURE
Urban agriculture includes agricultural production activities as well as related processing and
marketing activities as well as inputs (e.g. compost) and services delivery (e.g. animal health
services) by specialized micro-enterprises or NGOs, etc. In urban agriculture, production and marketing
tend to be more closely interrelated in terms of time and space than for rural agriculture, thanks to
greater geographic proximity and quicker resource flow.
PRODUCT DESTINATION / DEGREE OF MARKET ORIENTATION
In most cities in developing countries, an important part of urban agricultural production is for self-
consumption, with surpluses being traded. However, the importance of the market-oriented urbanagriculture, both in volume and economic value, should not be. Products are sold at the farm gate, by
cart in the same or other neighborhoods, in local shops, on local (farmers) markets or to inter-med iaries
and supermarkets. Mainly fresh products are sold, but part of it is processed for own use, cooked and
sold on the streets, or processed and packaged for sale to one of the outlets mentioned above.
SCALES OF PRODUCTION AND TECHNOLOGY USED
In the city, we may encounter individual or family farms, group or cooperative farms and commercial
enterprises at various scales ranging from micro- and small farms (the majority) to medium-sized and
some large-scale enterprises. The technological level of the majority of urban agriculture enterprises in
developing countries is still rather low. However, the tendency is towards more technically advanced
and intensive agriculture and various examples of such can be found in all cities.
WHY IS URBAN AGRICULTURE IMPORTANT?
The rapid urbanization that is taking place goes together with a rapid increase in urban poverty
and urban food insecurity. By 2020 the developing countries of Africa, Asia, and Latin America will be
home to some 75% of all urban dwellers, and to eight of the anticipated nine mega-cities with
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populations in excess of 20 million. It is expected that by 2020, 85% of the poor in Latin America, and
about 40-45% of the poor in Africa and Asia will be concentrated in towns and cities.
Most cities in developing countries have great difficulties to cope with this development and are unable
to create sufficient formal employment opportunities for the poor. They also have increasing problems
with the disposal of urban wastes and waste water and maintaining air and river water quality.
Urban agriculture provides a complementary strategy to reduce urban poverty and food
insecurity and enhance urban environmental management. Urban agriculture plays an important role in
enhancing urban food security since the costs of supplying and distributing food to urban areas based on
rural production and imports continue to increase, and do not satisfy the demand, especially of the
poorer sectors of the population. Next to food security, urban agriculture contributes to local economic
development, poverty alleviation and social inclusion of the urban poor and women in particular, as well
as to the greening of the city and the productive reuse of urban wastes (see below for further
explanations and examples).
The importance of urban agriculture is increasingly being recognized by international organizations like
UNCED (Agenda 21), UNCHS (Habitat), FAO (World Food and Agriculture Organization), and CGIAR
(international agricultural research centers).
1. FOOD SECURITY AND NUTRITION
The contribution of urban agriculture to food security and healthy nutrition is probably its most
important asset. Food production in the city is in many cases a response of the urban poor to inadequate,
unreliable and irregular access to food, and the lack of purchasing power.
Most cities in developing countries are not able to generate sufficient (formal or informal) income
opportunities for the rapidly growing population. The World Bank (2000) estimates that approximately
50% of the poor live in urban areas (25% in 1988). In urban settings, lack of income translates more
directly into lack of food than in a rural setting (cash is needed). The costs of supplying and distributing
food from rural areas to the urban areas or to import food for the cities are rising continuously, and it is
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expected that urban food insecurity will increase.
Food prices in Harare, for example, rose 534 percent between 1991 and 1992 due to the removal of
subsidies and price controls, spurring poor urban consumers to get access to food outside of market
channels through home production or bartering .Urban agriculture may improve both food intake
(improved access to a cheap source of proteins) and the quality of the food may improve (poor urban
families involved in farming eat more fresh vegetables than other families in the same income category).
In addition to production for their own consumption needs, large amounts of food are produced for
other categories of the population. It is estimated (UNDP 1996; FAO 1999) that 200 million urban
residents provide food for the market and 800 million urban dwellers are actively engaged in urban
agriculture in one way or another. These urban farmers produce substantial amounts of food for urban
consumers. A global estimate (data 1993) is that 15-20% of the worlds food is produced in urban areas.
Over 26000 popular gardens cover 2438,7 hectares in Havana and produce 25000 tons of food each
year; a total of 299 square kilometers of urban agriculture produces 113525 tons/year.
Urban agriculture to a large extent complements rural agriculture and increases the efficiency of
the national food system in that it (IDRC 1998) provides products that rural agriculture cannot supply
easily (e.g. perishable products, products that require rapid delivery upon harvest), that can substitute for
food imports and can release rural lands for export production of commodities.
2. ECONOMIC IMPACTS
Growing your own food saves household expenditures on food; poor people in poor countries
generally spend a substantial part of their income (50 70%) on food. Growing the relatively expensive
vegetables therefore saves money as well as on bartering of produce. Selling produce (fresh or
processed) brings in cash.
Besides the economic benefits for the urban agricultural producers, urban agriculture stimulates
the development of related micro-enterprises: the production of necessary agricultural inputs and the
processing, packaging and marketing of outputs. The activities or services rendered by these enterprises
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may owe their existence in part or wholly to urban agriculture. Other services may also be rendered by
independent families and groups (e.g. animal health services, bookkeeping, transportation).Input
production and delivery may include activities like the collection and composting of urban wastes,
production of organic pesticides, fabrication of tools, delivery of water, buying and bringing of chemical
fertilizers, etc.)
Transformation of foodstuffs may include the making of yoghurt from milk, or the frying of
plantains or yams, chicken or eggs, etc. This might be done at the household level, to sell at the farm
gate or in a local shop or market, and larger units to sell in supermarkets or even for export. Special
attention is needed for the strengthening of the linkages between the various types of enterprises in
clusters or chains. The municipality and sectoral organisations can play a crucial role in stimulating
micro-enterprise development related to urban agriculture.
3. SOCIAL IMPACTS
Urban agriculture may function as an important strategy for poverty alleviation and social
integration. We mentioned earlier the positive stimulus it may give to women.
Several examples exist of municipalities or NGOs that have initiated urban agriculture projects that
involve disadvantaged groups such as orphans, disabled people, women, recent immigrants without jobs,
or elderly people, with the aim to integrate them more strongly into the urban network and to provide
them with a decent livelihood. The participants in the project may feel enriched by the possibility of
working constructively, building their community, working together and in addition producing food and
other products for consumption and for sale.
In more developed cities, urban agriculture may be undertaken for the physical and/or
psychological relaxation it provides, rather than for food production per se. Also, urban and peri-urban
farms may take on an important role in providing recreational opportunities for citizens (recreational
routes, food buying and meals on the farm, visiting facilities) or having educational functions (bringing
youth in contact with animals, teaching about ecology, etc.).
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4. CONTRIBUTIONS TO URBAN ECOLOGY
Urban agriculture is part of the urban ecological system and can play an important role in the urban
environmental management system. Firstly, a growing city will produce more and more wastewater and
organic wastes. For most cities the disposal of wastes has become a serious problem. Urban agriculture
can help to solve such problems by turning urban wastes into a productive resource.
In many cities, local or municipal initiatives exist to collect household waste and organic refuse from
vegetable markets and agro-industries in order to produce compost or animal feed, but one can also find
urban farmers who use fresh organic waste (which may cause environmental and health problems).
Quality compost is an important input that can fetch a good price, as the example from Tanzania
shows. Compost allows an urban farmer to use less chemical fertilisers and by doing so preventing
problems related to the contamination of groundwater. In addition, compost-making initiatives create
employment and provide income for the urban poor.
Farmers may use wastewater for irrigating their farms when they lack access to other sources of
water or because of its high price. The use of fresh (untreated) wastewater has the additional advantage
for poor urban farmers that it contains a lot of nutrients (although often not in the proportions required
by their soils and crops). However, without proper guidance, the use of wastewater may lead to health
and environmental problems. Farmers need to be trained in self- protection during handling of the
wastewater, proper crop selection and adequate irrigation methods, among other things.
Technologies such as hydroponics or organoponics, drip irrigation, zero tillage etc. substantially
reduce water needs and health risks and are very interesting for the urban environment and can indeed be
found in many cities.
The treatment and reuse of more urban wastewater in agriculture also needs to be ensured. This
necessitates special decentralised treatment facilities and low cost (preferably bio-) technologies. In
many cases, partial treatment will be optimal for agricultural reuse. More and more experience is being
gained in public-private initiatives involving private enterprises and/or civic organizations in the
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development and management of municipal wastewater treatment plants.
Secondly, urban agriculture may also positively impact upon the greening and cleaning of the city by
turning derelict open spaces into green zones and maintaining buffer and reserve zones free of housing,
with positive impacts on the micro-climate (shade, temperature, sequestration of CO2).
Degraded open spaces and vacant land are often used as informal waste dumpsites and are a source of
crime and health problems. When such zones are turned into productive green spaces, not only an
unhealthy situation is cleared, but also the neighbours will passively or actively enjoy the green area.
Such activities may also enhance community self-esteem in the neighbourhood and stimulate other
actions for improving the community's livelihood.
MOST FREQUENT DISEASES OF URBAN PLANTS
INTRODUCTION
Parasitic Diseases
FUNGI NEMATODES
Phymatotrichopsis Root RotRoot-knot Nematodes
Phytophthora Disease PARASITIC HIGHER PLANTS
Pythium Disease Mistletoes
Rhizoctonia Disease NONPARASITIC DISEASES
Verticillium and Fusarium Wilts Aleppo Pine Blight
Powdery Mildew Scorch
Rust Diseases Arizona Ash Decline
Cytospora Canker Mulberry Tree Decline
Oleander Decline
Sooty Canker SALT PROBLEMS
Wood Rots and Decays MISCELLANEOUS PROBLEMS
http://ag.arizona.edu/pubs/diseases/az1124/#introduction%23introductionhttp://ag.arizona.edu/pubs/diseases/az1124/#nematodes%23nematodeshttp://ag.arizona.edu/pubs/diseases/az1124/#prr%23prrhttp://ag.arizona.edu/pubs/diseases/az1124/#rn%23rnhttp://ag.arizona.edu/pubs/diseases/az1124/#phyd%23phydhttp://ag.arizona.edu/pubs/diseases/az1124/#parasitic%23parasitichttp://ag.arizona.edu/pubs/diseases/az1124/#pyd%23pydhttp://ag.arizona.edu/pubs/diseases/az1124/#m%23mhttp://ag.arizona.edu/pubs/diseases/az1124/#rhd%23rhdhttp://ag.arizona.edu/pubs/diseases/az1124/#nd%23ndhttp://ag.arizona.edu/pubs/diseases/az1124/#vfw%23vfwhttp://ag.arizona.edu/pubs/diseases/az1124/#apb%23apbhttp://ag.arizona.edu/pubs/diseases/az1124/#pm%23pmhttp://ag.arizona.edu/pubs/diseases/az1124/#s%23shttp://ag.arizona.edu/pubs/diseases/az1124/#rust%23rusthttp://ag.arizona.edu/pubs/diseases/az1124/#aad%23aadhttp://ag.arizona.edu/pubs/diseases/az1124/#cytospora%23cytosporahttp://ag.arizona.edu/pubs/diseases/az1124/#mtd%23mtdhttp://ag.arizona.edu/pubs/diseases/az1124/#od%23odhttp://ag.arizona.edu/pubs/diseases/az1124/#sc%23schttp://ag.arizona.edu/pubs/diseases/az1124/#sp%23sphttp://ag.arizona.edu/pubs/diseases/az1124/#wrd%23wrdhttp://ag.arizona.edu/pubs/diseases/az1124/#mp%23mphttp://ag.arizona.edu/pubs/diseases/az1124/#introduction%23introductionhttp://ag.arizona.edu/pubs/diseases/az1124/#nematodes%23nematodeshttp://ag.arizona.edu/pubs/diseases/az1124/#prr%23prrhttp://ag.arizona.edu/pubs/diseases/az1124/#rn%23rnhttp://ag.arizona.edu/pubs/diseases/az1124/#phyd%23phydhttp://ag.arizona.edu/pubs/diseases/az1124/#parasitic%23parasitichttp://ag.arizona.edu/pubs/diseases/az1124/#pyd%23pydhttp://ag.arizona.edu/pubs/diseases/az1124/#m%23mhttp://ag.arizona.edu/pubs/diseases/az1124/#rhd%23rhdhttp://ag.arizona.edu/pubs/diseases/az1124/#nd%23ndhttp://ag.arizona.edu/pubs/diseases/az1124/#vfw%23vfwhttp://ag.arizona.edu/pubs/diseases/az1124/#apb%23apbhttp://ag.arizona.edu/pubs/diseases/az1124/#pm%23pmhttp://ag.arizona.edu/pubs/diseases/az1124/#s%23shttp://ag.arizona.edu/pubs/diseases/az1124/#rust%23rusthttp://ag.arizona.edu/pubs/diseases/az1124/#aad%23aadhttp://ag.arizona.edu/pubs/diseases/az1124/#cytospora%23cytosporahttp://ag.arizona.edu/pubs/diseases/az1124/#mtd%23mtdhttp://ag.arizona.edu/pubs/diseases/az1124/#od%23odhttp://ag.arizona.edu/pubs/diseases/az1124/#sc%23schttp://ag.arizona.edu/pubs/diseases/az1124/#sp%23sphttp://ag.arizona.edu/pubs/diseases/az1124/#wrd%23wrdhttp://ag.arizona.edu/pubs/diseases/az1124/#mp%23mp7/31/2019 Urban Agriculture & Plant Pathology by Mian Nasir
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Ganoderma Root Rot
Bacteria
Crown Gall
Oleander Gall
Fire Blight
Bacterial Necrosis Of Saguaro
Wedgwood or Slime Flux
URBAN PLANT PATHOLOGY
It deals with the management of diseases in the urban agriculture system and to make strategies
according to urban agriculture for control of diseases and to halt their further spread.
Urban plant pathology has its deep interrelationship with the phytosanitary which can be
explained well in terms of an overall control and management of diseases. An urban agriculture that is
established and then further maintained over the strong foundation of phytosanitary practices, can lead to
a superb output. it is only the cleanliness or sanitary that lies behind the secrets of fighting against pests
diseases and other sort of contamination or disorders. Phytosanitary regulation is an official rule to
prevent spread of quarantine pests by regulating the production movement are existence of commodities
or other articles. Thereby establishing schemes for phytosanitary certification. Therefore, all countries
have to maintain measures to ensure that food is safe for the consumers and dissemination or spread of
diseases or pathogens is prevented among the growing plants.
PRESENT AND FUTURE DIRECTIONS OF URBAN PLANT PATHOLOGY:-
Studies have revealed that urbanization has great impact on plant pathology. It has been
confirmed that more diseases are prevalent in cities than in rural areas. In a study, it was revealed that
urbanization alters the functional composition, but not the taxonomic diversity of the pathogens. For
example, soil borne pathogens such as fungi, nematodes and some bacteria which can be introduced
through foreign soils, infected material or water, survive for long periods and under favorable conditions
http://ag.arizona.edu/pubs/diseases/az1124/#grr%23grrhttp://ag.arizona.edu/pubs/diseases/az1124/#bacteria%23bacteriahttp://ag.arizona.edu/pubs/diseases/az1124/#cg%23cghttp://ag.arizona.edu/pubs/diseases/az1124/#og%23oghttp://ag.arizona.edu/pubs/diseases/az1124/#fb%23fbhttp://ag.arizona.edu/pubs/diseases/az1124/#bns%23bnshttp://ag.arizona.edu/pubs/diseases/az1124/#wsf%23wsfhttp://ag.arizona.edu/pubs/diseases/az1124/#grr%23grrhttp://ag.arizona.edu/pubs/diseases/az1124/#bacteria%23bacteriahttp://ag.arizona.edu/pubs/diseases/az1124/#cg%23cghttp://ag.arizona.edu/pubs/diseases/az1124/#og%23oghttp://ag.arizona.edu/pubs/diseases/az1124/#fb%23fbhttp://ag.arizona.edu/pubs/diseases/az1124/#bns%23bnshttp://ag.arizona.edu/pubs/diseases/az1124/#wsf%23wsf7/31/2019 Urban Agriculture & Plant Pathology by Mian Nasir
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multiply and result in the build up of inoculum potential in a locality. Viral diseases are mainly
introduced by insect vectors or infected seeds or vegetative material but once introduced in an area are
difficult to eradicate. Therefore, the discipline of plant pathology is likely to be strengthened in its
concept and application in urban agriculture.
FOOD SAFETY AND QUALITY
In recent years, food safety has been threatened by a number of events and developments that
allow food borne microorganisms or pathogenic to reach humans, e.g. the bacteria salmonella, listeria,
Escherichia coli, some protozoa and the hepatitis a virus. These contaminate the food in a variety of
ways; therefore, food produced must be free from contaminants, preservatives and pesticide residues and
their metabolites, as people are now much more conscious of these problems. Phytosanitry measures and
occasional inspections can eliminate these problems.
PLANT PATHOLOGY AS A PROFESSION IN URBAN AGRICULTURE:
In many parts of the world where urban agriculture was introduced and developed on highly
scientific lines, considerable efforts have been made to broaden both plant ;health and plant protection.
The American Psychopathological Society realizing the need for such a broader concept has launched a
new electronic journal called Plant Health Progress: which published articles on all facts of plant
health. The society is also emphasizing on the production of professional graduates in urban plant
pathology and doctors of plant medicine program.
PLANT DISEASE CLINICS:-
The functions and practices of plant pathology, e.g. collection of diseased specimens, their
examination, proper identifications of pathogens, communication and recommendations, are performed
by the highly specialized professors and researchers who have advanced knowledge in their respective
fields. They come from the universities, Research and Extension departments. However, these activities
are carried out occasionally at much lower scientific ad professional levels and unorganized basis with
no inventory records. With the onset of urban agriculture, time has come now that plant disease clinics
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are also initiated in big cities as medicines and veterinary clinics. Plant disease clinics can actively
involve in site visits, collection of diseased samples, their timely examination and proper
recommendations. Growers and country agents, home growers can also send disease plants, soil with
disease plants and some time insects to plant disease clinic for identification, control measures all free or
nominal charges. Plant disease clinic can be equipped primarily with surface sterilants, dissecting
microscopes, culture dishes and test tubes, nutrient media for culturing fungi and bacteria. At the same
time, nematode isolation from roots or soil can be made. Diagnosis of vial diseases (bases on
symptomatology and host range) can become integral function of the plant disease clinics.
APPLICATION OF NEW TECHNOLOGY:-
A ) MOLECULAR PLANT PATHOLOGY:-
The molecular phase of plant pathology is expected to develop a great deal more and to make
contributions in ways that we can hardly imagine at present. One area in which molecular plant
pathology is expected to greatly contribute and to provide tremendous benefits is the area of detection,
identification, isolation, modification, transfer and expression of genes for disease resistance from one
plant to another. Several such resistance genes have already been identified, isolated, transferred into
susceptible plants, and when expressed made the plants resistant. The possibility that molecular plant
pathology can modify and combine resistance genes makes likely the future utilization of resistance
genes from unrelated plants or from other organisms and perhaps even the synthesis of artificial genes
for resistance for incorporation into crop plants. The practical implication of such developments cannot
be overestimated, as they are likely to revolutionize the control of plant disease by providing us with
cultivars that can resist disease in the presence of the pathogen, without the need to use any pesticides.
Urban agriculture is the best to test and utilize these innovations.
B) PLANT BIOTECHNOLOGY
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It is the use of tissue culture and genetic engineering techniques to produce genetically modified
transgenic plants that exhibit new or improved desirable characteristics. A large number of crops,
ornamental, and forest plants have been modified and released by various organizations around the
world. Practical examples of successfully engineered and disease resistant plants include melon, squash,
tomato, tobacco ad papaya that are protected from a variety of viral diseases. Classical Cross Protection
and Engineered Protection are highly promising and fit very well for application I urban agriculture.
Several viral diseases are now controlled; the best example is control of papaya crop from Papaya Ring
Spot Poty virus (PRSV)
SPECIFIC STRATEGIES FOR THE MANAGEMENT OF DISEASES IN URBAN
AGRICULTURE
To conduct research on urban agriculture and the diseases related to urban agriculture, build
collaboration between government and farmers to control diseases to ensure food security.
To conduct research on ecological, socioeconomic, nutritional, policy related and environmental
dimensions of urban agriculture and alternative food systems.
To set up, within a working urban farm, experimental plots where various alternative technologies of
crop management (e.g. biological pest control, organic soil management, intercropping designs, raised
beds, bio dynamics farming techniques and permaculture, etc) are researched for optimal yields,
sustainability, economic viability and land / labour productivity.
EDUCATION:-
To establish programs to teach graduates and undergraduates students the theory and practices of
urban agriculture and alternative urban food system to control disease and ensure food security.
To establish a clearing house/resource centre to meet the particular need of public school teachers and
administrators. Such a resource centre would offer information about curricula and activities which help
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integrate gardening into the current curriculum and meet the state mandated subject frameworks, offer
funding information and ideas for developing a sustainable gardening program, offer information about
coordinating a school garden with the school custodial, lunch program, local business and the larger
school community.
To train community members in environmentally sound methods of controlling diseases and ensure food
security and food production through hand on learning and field practices in organic horticultural
methods, fields days, workshops, seminars, plant clinic etc.
EXTENSIONS:
In order to control diseases in urban agriculture, a policy is needed among scientists/extension
workers and farmers/nursery holders on the implementation of programs and organizes training courses.
REFERENCES
http://www.ruaf.org/node/513
http://ag.arizona.edu/pubs/diseases/az1124/#phyd
http://www.cityfarmer.org/uajustification.html
http://en.wikipedia.org/wiki/Urban_agriculture
Notes Given By Dr.S.M.Mughal
http://www.urbanfarming.org/
http://www.ruaf.org/node/513http://ag.arizona.edu/pubs/diseases/az1124/#phydhttp://www.ruaf.org/node/513http://ag.arizona.edu/pubs/diseases/az1124/#phyd