Pollinators, Pests, and Diseases

A more recent strategy for protecting plants from pests and disease involves the use of genetically altered plants. This method is controversial. Concerns include cross-pollination with unaltered plants and the entry of altered plants into the food supply. 

Perennial farming systems with tree, bush or vine crops also provide niches for short and longer term intercropping. In addition to the use of cover crops on the orchard floor of many crops including apples (Hartley ef al. 2000) and wine grapes (Bugg ef al. 1996), plantings of commercially and environmentally valuable species within or around the orchard have also been used for pollination, disease and pest control (Finckh and Wolfe 1998, Altieri 1999) in crops such as such as leeks (Baumann ef al. 2001) and carrots (Brandsseter and Riley 2002). 

The bioactive compounds isolated from plants and responsible for the medicinal properties mentioned here and different health -improving effects are named secondary metabolites [9]. It is generally believe that they do not play an essential role in plant growth and development. However, they participate in plant adaptation responses and defense functions. It is well known that these compounds play an important role in their survival in the ecosystem because they are involved in the resistance against pests, diseases and other functions such as attraction of pollinators and interactions with organisms of their enviromnent [1, 6, 9]. 

---