To what aspect of hinduism did subodh gupta refer in his work dada?

The answer is "yakshi sculptures".

A yakshi is a female earth soul, acknowledged as a symbol of fertility by the Hindu, Buddhist, and Jain beliefs. She is typically depicted as a wide-hipped, curvy lady, who can make a tree prove to be fruitful just by contacting it with her foot. The figure depicted here is astutely joined into the type of a segment, the capital of which appears as a verdant tree. Her high ground gets a handle on a branch of the tree, a customary motion in models of yakshi. This stance is one of conceiving an offspring, permitting the draw of gravity (the earth getting) to aid the conveyance of life.  

Sculptures of yakshi are regularly observed in expound engineering themes on the façades of sanctuaries and stupas. Figures, for example, this one, frequently perceived as "mother-goddesses," go back to the Indus Valley human progress (2500– 1750 B.C.), the soonest known urban culture of India.

to stay where they were until m sent for