In addition, the biotic stresses also do not allow successful production of vegetables like capsicum, cucumber, tomato, chilli, okra/bhindi, cauliflower, cabbage, leafy vegetables etc. in the fields mainly during rainy and winter season. In spite of the great importance of vegetable crops, it faces a lot of restraints like temperature stress, photostress, moisture stress and weeds growth, nutrients deficiency in the soil, excessive wind velocity and atmospheric CO2. Some possible ways to reduce green house gas emissions are suggested and some sustainable adaptation strategies are indicated. We expand our survey of the existing research to the entire production system, including greenhouse structure, energy, electricity, growing media, and fertilizers. Different protected cultivation structures having different temperature, humidity, UV radiation ranges and also having different cost involvement in construction of structure which may results the production of vegetables with distinct advantage of good quality fruits, productivity and favorable market price to the growers/farmers. These limitations can be alleviated by adopting a unique, specialized hi-technology is called as protected cultivation. Intense heat and high incidence of UV rays in dry months reduce the quality of leafy vegetables in open which otherwise very good in protected structures. Protected cultivation has great scope to achieve self-sufficiency in vegetable sector even with less area. The shade net house is ideal for cultivation of vegetable during dry period in the tropical islands when extreme sunshine and heat are limiting factor to vegetable production. These structures are constructed using a UV stabilized agro-shade net (35%-70% shade) materials for creating partial shade condition inside the structure to favour the growth and development of partial shade requiring crops or to protect crop from scorching heat during hot/summer months. The partial shade effect helps in fast and better growth of leafy vegetables besides reducing the evapo-transpiration loss of water. Low cost shade net for high value leafy vegetables like coriander, palak, fenugreek and insect free brinjal crop. Consequently more pesticides are being used for protecting the crops which deteriorate the vegetable quality by the presence of residues. This also creates environmental concern as the limited soil and fresh water bodies are get contaminated. The net house can be used for year round cultivation of crops such as Capsicum, tomato, okra, cauliflower, cabbage, brinjal, beans, parthenocarpic cucumber and other cucurbits with reduced incidence of insect-pest and diseases and consequent low chemical residues on the produces. The cost can be reduced drastically by the use of local wood materials like bamboo/wooden poles. Vegetable growers can substantially increase their income by protected cultivation of vegetables in off-season as the vegetables produced during their normal season generally do not fetch good returns due to large availability of these vegetable in the markets. Off-season cultivation of cucurbits under low plastic tunnels is one of the most profitable technologies under northern plains of India. Protected cultivation enables us to grow vegetables in the off-season and also to extend the vegetable growing seasons for a much longer period than is possible under open field conditions. Though certain breakthroughs in vegetable cultivation in adverse climates using protected devices have been registered, more extensive research and generation of awareness are required to tap potential of protected cultivation of vegetable crops and also increase the area under protected devices.
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