@ T. R. Das, the evidence indicates that the earth's magnetic pull influences seed germination by acting as an auxin or plant hormone. The magnetic field also assists in ripening of such plants as tomatoes. Much of plant response is due to the cryptochromes, or blue light receptors, that plants bear. The earth magnetic field is generated by electric currents due to the motion of convection currents of a mixture of molten iron and nickel in the Earth's outer core: these convection currents are caused by heat escaping from the core, a natural process called a geodynamo.

Besides what M Patil has described above, another important aspect of directional sowing of the crops improves the light interception in the canopy resulting into the better photosynthesis and increased productivity in quality and quantity. The direction chosen will depend on the latitude and longitude and curvature of the sun angle at particular cropping season.

Wow, got to know very nice information regarding the influence of earth's magnetic field and it's importance to the crop growth. We all are aware of the crop growth in response to the solar radiation direction. Respected M Patil, could you please be elaborate the specific impact of the magnetic field in different crop species. Is there any research on this topic?

Please look at the abstract, in which we have tried with external magnetic field through irrigation water treatment and the results were promising with cowpea, brinjal, bhendi and few other vegetables.