The 15-year-old Aditi, bidding to retain her national title and also win the Order of Merit, was in awesome form and closed with three birdies in last four holes and had a 36-hole total for one-over 139.
Millie Saroha, who led after the first round, was second with a card of 73 that gave her a two-day aggregate of 143, while Gursimar Badwal (75-72) was third at 147.
Ridhima Dilawari (75-75) and Gurbani Singh (74-76) shared the fourth place.
Aditi, who seemed to be struggling during her opening round of 73, opened with a bogey. But she steadied herself and picked birdies on sixth and seventh. But a bogey on tenth set her back. She was then even par for the day.
But with Millie, her playing partner, going three over for the front stretch, the two players were alevel.
On the back nine, Aditi birdied 15th, 16th and 18th, while Millie managed a birdie only on 18th and the honours went to Aditi, who will now be fancying her chances in the main matchplay event.
The stage is now set for the matchplay segment with the top-16 moving into this part of the Championship.
All the leading players duly qualified for the this part, though Anisha Padukone had to beat Vidushi Sinha in the sudden death play-off hole to make the top 16.
Though Anisha won the sudden-death, her first round opponent will be Aditi Ashok, while Millie Saroha meets Shruti Naik.
This season Gurbani has won two regional titles, the Usha Southern India and Usha Western India titles, while Mille Saroha grabbed the Usha Northern India crown and Amandeep Drall won the Usha Eastern India.
The reigning All India Ladies and juniors champion, Aditi, has won twice, but in none of those were regional majors.
