New polyhouse tech for horticulture crops

Dr (Prof) Harish Hirani, Director, CSIR-Central Mechanical Engineering Research Institute, Durgapur, has inaugurated a "Naturally Ventilated Polyhouse Facility" and laid foundation stone of "Retractable Roof Polyhouse" at Ludhiana in Punjab.

Briefing about the technology, Prof Hirani said that the farmers face number of problems such as excessive or insufficient cold, heat, rain, wind, and other factors associated with insufficient transpiration, and also crop losses in India due to insect pests is about 15% at present and this loss may increase as climate change lowers the plant defence system against insects & pests. To some extent these problems can be overcome by conventional polyhouse. Conventional Polyhouse have a stationary roof to reduce the effect of weather anomalies and pests. However, there are still disadvantages due to roof covering which sometimes lead to excessive heat, and insufficient light (early morning). Besides this, they are also prone to insufficient levels of CO2, transpiration and water stress. A combination of open field conditions and conventional Polyhouse conditions is a more robust way to deal with the climate change and associates problems in the future. This all-weather structure will have an automatic retractable roof which will be operated based on weather conditions and crop requirements from the conditional database using PLC software. This ongoing development will help farmers to cultivate both seasonal and off-season crops which can fetch higher yield, firmer and high shelf-life produce by creating optimal indoor micro-climate conditions compared to conventional open field tunnels & naturally ventilated poly houses, and also it is viable technology for organic cultivation.