Valid Rural Certificates have reservations in KCET for 15% of the total government seats in KCET. Students with NCC 'B' Certificates who is a resident of Karnataka and has obtained their certificate in their study in Karnatak from Grade 8th to Grade 12th can also have reservations. The students who claim reservation via their NCC 'B' certificates must have attended certain camps/followed through a certain regime which can be checked from: 

https://engineering.careers360.com/articles/kcet-reservation-criteria

Ranganath , the answer to your question is no , the is no reservation for Ncc cadets in KCET whatsoever, however 15 percent of the seats in government colleges are reserved for rural candidates . And as far as using your b cert for reservation is concerned I believe there are colleges Delhi university ,who intake NCC cadets through a DST.