Diseases and Management of Crops under Protected Cultivation

(Diseases and Management of Crops under Protected Cultivation)
beneath the older cuticle therefore the insecticides prove ineffective in controlling them. The
dormant mites also do not feed, therefore the products that kill by ingestion proves futile.
Consequently, if only one application is made, some of the mites may survive and the infestation
will persist.
Traditonal management and their constraints
The warm, humid conditions and abundant food in a greenhouse provide an excellent,
stable environment for pest development. In closed systems the pest situations reach the alarming
level with great severity within no time as the natural enemies which control the pest are not
present in the greenhouse.
Several factors are responsible for successful control of insect pests on greenhouse
vegetables and ornamentals. Proper cultural practices, early detection and diagnosis and proper
choice of selective pesticides can minimize the chance for initiation and build-up of infestations.
Traditional management of pests generally involves pesticides that are specially developed
for pest control but resistance development is the most severe challenge to pest control. Most of
major pests today are characterized by very high pesticide resistance levels to various types of
active ingredient. A number of insects and mites have achieved global pest status due to pesticide
resistance combined with the intensive international trade in plant material. Greenhouses being a
closed system face this problem frequently as population of selected strain is not thinned by
outdoor wild population making the control difficult. There can also be detrimental effect of these
chemicals on non target species resulting in pest outbreaks and phytotoxic reactions by treated
plants.
The pesticide resistance and then consumer and environmental concerns are forcing
growers to replace simple pesticide based control programme by other, more sophisticated and
tactically broader integrated control systems.
Biorational Management
‣ Spray Azadirachtin @ 2%
‣ Spray horticultural oil @ 1%
‣ Apply calmite @ 2 ml/L
‣ Apply abamectin (vertimec) @ 0.5 ml/L as last resort due to high cost
Insecticidal Soap -- 1-2.5 gal/100 gal.
Paraffinic Oil -- 1-2 gal/100 gal.
Neem Oil -- 0.5-2% in 25-100 gal water per acre.
Neuronal inhibitors (unknown mode of action).
Bifenazate (PHI, 3 days; REI, 12 hrs). For various mite species. Registered only on tomato
varieties greater than 1 inch in diameter. Floramite: 3 g/10 L approx.
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