Hi Jashwanth,

Both Pushkaram College of Agricultural Sciences, Puddukotai and Krishna College of Agriculture and Technology, Madurai are developing good colleges. The infrastructure, educational system is well and good. Go for what you prefer and what is more important. Pushkaram is in Puddukotai, while Krishna is in Ussilampatty. Check for both the colleges and analyze where you could have more exposure (and field work, maybe) and where you could deepen your research skills. 

Best college depends on what are your preferences. Any college could be best if you are passionate enough. 

All The Best.