Which hormone promotes internode/petiole elongation in deep-water rice plants?

Which one of the following synthetic growth regulators is used to promote synchronized flowering in pineapple?

$PGR$ which was discovered by Cousins .........

When an unripe banana is sealed in a polythene bag,it remains green for many days. But if an apple is also sealed in the same bag,the banana ripens and turns yellow within a few days. The reason is that apple

Which hormone is produced mostly in all parts of a plant?

Ethylene is a