As i am confused we have to take care of time in which time of year that crop is harvested or we can work on any crop throughout the year? This is my MS thesis project so that's why I am confused for which crop should I go.
It depends to the goals of the research and the parameters that you would like to assess. For instance, if you are interested in assessing leaf index/ vegetation cover then the best time is mid-spring until summer but for salinity assessment we work with data acquired in autumn due to the precipitation of salts in the topsoil in that period.
You can select the major crop of your region. Ultimately the aim of the prediction is to get the farming community beneficial. Libery of choosing the crop rest with you.