Which of the following exerts the Richmond-Lang effect,i.e.,prevents the loss of chlorophyll?

Induction of cell division and delay in senescence is done by

Richmond-Lang effect is related with . . . . . . .

Farmers in a particular region were concerned that premature yellowing of leaves of a pulse crop might cause a decrease in the yield. Which treatment could be most beneficial to obtain maximum seed yield?

The cambial tissue of $Pinus radiata$ contains which of the following?

Zeatin has been obtained from