Seedless mango ‘Sindhu’ has been developed by backcross between:

✅Explanation:
The seedless mango cultivar 'Sindhu' was indeed developed through a backcross breeding program involving 'Ratna' and 'Alphonso' mangoes.
-Ratna is a popular mango variety known for its regular bearing and good fruit quality.
-Alphonso is a highly prized mango cultivar known for its exceptional flavor and aroma.
By crossing these two varieties and then backcrossing the offspring with 'Alphonso', scientists were able to develop 'Sindhu', which inherited the seedlessness trait from 'Ratna' and the desirable qualities of 'Alphonso'.