Application of molecular biology in plant nematology

Plant parasitic nematodes are major pests for crops. They significantly damage agriculture worldwide. It has been estimated that plant parasitic nematodes reduce the yield of the world's 40 major food staples and cash crop by about 12.5 % (Sasser, 1980). Furthermore, much of the crop damage caused by nematodes is unrecognized. However in spite of their impact on world agriculture, the basic biology of plant parasitic nematodes is poorly understood (Bird Mck. D., 1996). This can be explained by the difficulties in accumulating sufficient biological material to undertake biochemical and molecular biology studies. Most plant parasitic nematodes are microscopic, obligate root-parasites. One of the problems of working with plant parasitic nematodes is that they are difficult to grow: even when it is possible to collect enough material to perform a biochemical experiment, the eagerness to repeat the experiment is frustrated by the need to wait until new material is accumulated again! The control of plant parasitic nematodes relies on the application of nematicides to nematode infested fields, crop rotation and the use of resistant plant varieties as well. Only recently the development of new techniques has allowed researchers to address questions that can be answered in terms of biochemistry and molecular biology.