Diseases and Management of Crops under Protected Cultivation

(Diseases and Management of Crops under Protected Cultivation)
during the hot summer season are usually grafted onto Sintozwa rootstocks (Inter specific hybrid)
or others.
Various problems are commonly associated with grafting and cultivating grafted seedlings.
Major problems are the labour and techniques required for the grafting operation and post graft
handling of grafted seedlings for rapid healing for 7 to 10 days. An expert can graft 1200 seedlings
per day (150 seedlings per hour), but the numbers very with the grafting method. Similarly, the
post graft handling method depends mostly on the grafting methods. The problems could be
minimised or easily overcome by careful cultural management and wise selection of scion and
rootstock cultivars.
Since there is prohibition of Methyl bromide for disinfecting soils, there is a renewed
interest for grafting eggplant (and tomato) on rootstocks resistant to soil borne pathogens.
Even though there are many problems associated with cultivating grafted vegetable
seedlings, the need for successful grafted seedlings is growing rapidly. Breeding multipurpose
rootstocks and developing efficient grafting machines and techniques will undoubtedly encourage
increased use of grafted seedlings in many countries. Large-scale commercial production of
vegetable seedlings is expanding rapidly in many developed countries and this will lead to an
increased commercial supply and use of grafted vegetable seedlings throughout the world.
Production of Virus Free Vegetables by using Insect Proof Nets
Continuous cropping of vegetables in a particular area leads to build up of diseases and
their vectors. To reduce the problem one of method is to give rest period of 60 days it can be
during dry season so that the vector’s life cycle is discontinued. This also requires clean
cultivation so that all the plant and leaves are killed or removed so that the virus cycle is
discontinued. But in many areas this practice is not possible. First farmers don’t agree to stop
cropping, In many areas dry season is the production time, so other alternative is to grow the crop
under nets. Normally 40 mesh net is used which prevents most of the sucking insects to get
inside.
Net houses must have double entry sliding gates so that with the movement of farmer the
pest doesn’t get easy chance to get inside.
Nurseries should also be raised inside net-house to prevent the infection. Use of plastic mulching
sheet also reduces the population of sucking pests and thus reduces the chances of viral diseases
in the crop.
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