HI,
I am a MATLAB trainer having 2 year of MATLAB experience,now it is time for me to make you feel that i can complete your project that is image processing of paddyleaves and diagonoising it as healthy or diseased,i made a m-file for your project,
I had followed following steps,for example ,lets take a disease ''RICE BLAST''
1) I collected two different leaves images ,with or without disease,
2)for better analysis i ran image conversions commands,
3)then program generates histogram of both images,(with or without disease),by comparing these images we can diagonoising it as healthy or diseased,
and this helps you in having project as you want..so smile :-)