Yes, you can get admission in decent college for MBA in Agribusiness management programme. Your performance in Class 12 will not impact your selection process a lot but you might need to give justification, if asked about your academic performance in Class 12. If you wish to pursue the MBA in Agribusiness, then you must meet the programme specific minimum eligibility criteria, appear for the entrance examination, and must perform well in the WATPI/ GDPI process conducted by the respective business school where you want to get admission.