Abstract:
Greenhouses are structures used for offseason cultivation of crops and also for obtaining
maximum production from unit area. In greenhouses, crop growing environment as well as
growing medium can be modified by adopting suitable technologies for microclimate control and
water and fertilizer application. Manual controls of microclimate and water and fertilizer
application are time and labour consuming and hence automation is required for the better
greenhouse management. The study entitled “Evaluation and refinement of low cost automation
system for naturally ventilated greenhouses” was conducted during the period July 2015 to
February 2017 to modify the existing low cost automation system at ARS Anakkayam and also
for its performance evaluation. Existing automation system has limitations such as it cannot
manage temperature and relative humidity separately and also it cannot manage irrigation and
fertigation. These problems were rectified in refined automation system. The refinement of the
system was done by changing the microcontroller used in the automation system and also using a
timer for the timely management of irrigation and fertigation. The refined system was capable of
managing temperature and relative humidity separately and performing irrigation and fertigation
operations inside the greenhouse. The refined automation system was tested without crop and
with crop during three crop seasons with salad cucumber crop (variety Saniya) inside the
greenhouse. The experiment was conducted inside a naturally ventilated greenhouse situated at
the ARS, Anakkayam, under Kerala Agricultural University. For comparison, salad cucumber
was cultivated inside another greenhouse which is manually controlled. Microclimate as well as
crop data were collected from outside the greenhouse and both these greenhouses and compared.
The temperature inside the AGH was less compared to NAGH and the relative humidity inside
the automated greenhouse never exceeded above 70%. The yield and all other crop parameters
were better in AGH compared to NAGH.
