Diseases and Management of Crops under Protected Cultivation

(Diseases and Management of Crops under Protected Cultivation)
Biological Control of Soil Borne Pathogens under Green House
Conditions
J. Kumar
Department of Plant Pathology, G.B.P.U.A.& T., Pantnagar-263 145 (UK)
Global scenario of green house/protected cultivation: Green house cultivation is a form of
protected cultivation which has some level of control over plant microclimate to alleviate one or
more of abiotic stress for optimum plant growth. The green house technology is more than 200
year old and Europeans were considered the pioneers in this field. Later with the advent of plastic
during World War II a new phase in the glass house technology emerged. The world’s total
greenhouse area is more than 307,000 ha which includes both plastic and glass poly houses.
There are more than 50 countries in the world where cultivation of crops is undertaken on a
commercial scale under cover. Green houses permit production of crops even in areas where
winters are severe and extremely cold as in Canada and Russia, and also in areas where
summers are extremely intolerable as in Israel, UAE, and Kuwait.
Country wise area under green house crop production
Country
USA
Spain
Italy
The Netherlands
Israel
Egypt
China
Japan
South Korea
Area under green house production
>400 ha
25,000 ha
18,500 ha
89,600 ha
15,000 ha
1000 ha
48,000 ha
>40,000 ha
>21,000 ha
Status of Green house cultivation in India: In India green house technology is still in its nascent
stage. The area under green/poly house cultivation, in the end of 2011 was about 2000 hectares.
Maharashtra, Uttarakhand, Karnataka and Jammu & Kashmir are the major states having
cultivation of crops under green house. According to the Directorate of Horticulture, Govt. of
Uttarakhand, in 2011, the total area under polyhouse in Uttarakhand is 200ha. Vegetables,
flowers, medicinal and aromatic plants are considered as most successful and revenue generating
crops grown in this technology. All these crops have high productivity in green houses due to
reduction in competition, healthy environment, better nutrient management, increased surface
area and longer crop duration.
Disease Problems in Greenhouses: The ideal and stable environment with warm, humid and
abundant food under green house provides an excellent platform for the development of diseases
often more than field conditions. Most pathogens cannot be excluded from the greenhouse
environment, for example airborne spores enter through doors and screens; soilborne pathogens
enter through dust or contaminated soil on shoes, tools, or equipment; and many pathogens are
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