To improve crop management, a number of sensors and instruments can (and should) be used to gather information in the greenhouse. Medium and high technology greenhouses make use of a range of sensors which link into automated control systems. These systems can monitor temperature, relative humidity, vapor pressure deficit, light intensity, electrical conductivity (feed and drain), pH (feed and drain), carbon dioxide concentrations, wind speed and direction and even whether or not it is raining. 

Source: http://www.greenhouse-management.com/greenhouse_management/greenhouse_environmental _control_systems/greenhouse_sensors.htm

To improve crop management, a number of sensors and instruments can (and should) be used to gather information in the greenhouse. Medium and high technology greenhouses make use of a range of sensors which link into automated control systems. These systems can monitor temperature, relative humidity, vapor pressure deficit, light intensity, electrical conductivity (feed and drain), pH (feed and drain), carbon dioxide concentrations, wind speed and direction and even whether or not it is raining. 

Source: http://www.greenhouse-management.com/greenhouse_management/greenhouse_environmental _control_systems/greenhouse_sensors.htm

Dear suresh K Malhotra sir , I thank you for your response 

my question is on smart green houses where I can apply sensor fusion methodology. I have already implemented individual sensors in my previous project , now I await to move a head in my research on fusing this values and getting better decision results for high precision agriculture.

https://www.ispag.org/abstract_papers/papers/abstract_1080.pdf

With precision agriculture, control centers collect and process data in real time to help farmers make the best decisions with regard to planting, fertilizing, and harvesting crops. They place sensors throughout the fields to measure the temperature and humidity of the soil and the surrounding air. In addition, these control centers take pictures of fields using satellite imagery and robotic drones.

Analog Devices (ADI) eagerly accepted the challenge and has been working with Gouillart and the entire farm-to-table supply chain ever since. ADI is developing the core technology through its Fenway development platform (Fig. 1), which includes several of the company’s proprietary sensors and a microcontroller. ADI is also leveraging multiple technical agreements or partnerships with other companies. In fact, ADI recently announced an agreement with Consumer Physics, which offers SCiO, a molecular sensing device being integrated into the “Internet of Tomatoes” approach. ADI also provides the rapid-prototyping team needed to constantly adapt the technology to the needs of tomato farmers and other value-chain players in various parts of the world.

The Internet of Tomatoes project provides a neutral, transparent, data-driven view of productivity and quality along the tomato chain that will lead the various actors to different, mutually beneficial choices, thereby leading to a transformation of the entire value chain and fostering the development and sales of the enabling technologies and associated services.

A Review of Combine Sensors for Precision Farming (Precision Agriculture June 2002, Volume 3, Issue 2, pp 169–182)

Abstract : To maximize economic return from agricultural production units, costs have to be minimized and benefits maximized. For grain, kernel yield and quality have to be maximized while the use of seeds, fertilizer, herbicides and fungicides have to be optimized. The best location to evaluate productivity levels, by measuring yield and quality of grain and straw, is the combine harvester. Moreover, other grain quality characteristics like density or test weight can be determined for use as an evaluation tool. In this paper, an overview is given of the past and current research toward the evaluation of currently available commercial sensors (e.g., for measuring grain yield and grain moisture content) as well as toward the development of new sensors (e.g., grain protein content and straw yield).

Dear anoop Kumar sir 

i highly appreciate for your response and the papers you shared are of great help to me

thank you