Agriculture must supply all people with enough food to prevent widespread hunger and starvation. However, food security is aggravating day by day, resulting in more number of undernourished/malnourished persons in the world. The ever-increasing population in the developing and less developed countries is also a major constraint. With climate changes in future, natural calamities (drought, flood, forest fire, fluctuation in rainfall pattern, etc.) will be a serious threat to human survival by way of availability of foods. Moreover, if food plants (cultivated and wild species) are utilized for the production of renewable liquid biofuel, there would be enormous changes in agroecosystems, destabilizing the natural balance and leading to lower productivity of food crops.