Disjoint Groups Sudoku (Mini Sudoku Series #84)

Disjoint Groups Sudoku is one of the Sudoku types which I am still very slow in solving. However, I am trying to improve in this Sudoku type. When we decided to create this Sudoku type for Sudoku Mahabharat 2016 Twisted Classics round, it was tough for me to create this Sudoku which uses the variants rules quite a lot. I had to practice a lot before creating some of the Sudoku puzzles Disjoint Groups Sudoku type. Most of my attempts to create this Sudoku type resulted in me creating a Classic Sudoku puzzle. Anyway, this was the puzzle among a few puzzles of this type that use the variant rules and was used in the Sudoku Mahabharat championship. There are another couple of puzzles that I will twist to make these puzzles better before posting.  
Anyway, currently this Disjoint Groups Sudoku puzzle I am posting in Mini Sudoku Series as 84th Sudoku in this series. Can you solve this Sudoku puzzle?

Rules of Disjoint Groups Sudoku

Disjoint Groups Sudoku (Mini Sudoku Series #84)

Disjoint Groups Sudoku (Mini Sudoku Series #84) Solution
Previous Mini Sudoku Extra Region Sudoku (Mini Sudoku Series #83)

Next Mini Sudoku Twin Givens Sudoku (Mini Sudoku Series #85)

Below is the answer to Disjoint Groups Sudoku, which is published with the title Disjoint Groups Sudoku Puzzles (Fun With Sudoku #261)

Disjoint Groups Sudoku (Fun With Sudoku #261) Puzzle Solution