For dual degree on botany and biotechnology in Thiruvananthapuram Kerala colleges are
St. Xaviers College, Thiruvananthapuram Kerala
Mar Ivanios College Thiruvananthapuram
Emmanuel College,Vazhichal,Thiruvananthapuram
For more information you can visit here

https://university.careers360.com/colleges/list-of-bsc-degree-colleges-in-thiruvananthapuram

Out of Thiruvananthapuram
Name of colleges
SNGM Arts and Science college,Alappuzha
Sree Narayana College, Kollam
Bishop Moore College,Alappuzha
Sree Narayana College of Technology, kollam

You can click here for more dual degree information

https://university.careers360.com/colleges/list-of-dual-degree-universities-in-india

https://university.careers360.com/colleges/list-of-dual-degree-in-sciences-degree-colleges-in-india

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