Germplasm can be collcted from many sources, where the preferred source to develop disease resistance is

1. Improved variety
2. Wild relative
3. Local variety
4. Plantlet from culture experiment

The correct option is 2.
A germplasm is a collection of genetic resources for an organism. For plants, the germplasm may be stored as a seed collection (even a large seed bank) or, for trees, in a nursery. Animal as well as plant genetics may be stored in a gene bank or cryobank.