Jenny Harris, of Balclutha Primary School, asks :-
How common are four and five leaf clovers?
Derek Woodfield, a clover geneticist with AgResearch Limited, responded.
Multifoliolate leaves (i.e. more than the normal three leaflets on trifoliolate leaves of common clovers) have been reported in many legume species including white clover (Trifolium repens), red clover (Trifolium pratense), crimson clover (Trifolium incarnatum), soybean (Glycine max) and lucerne (Medicago sativa). The frequency of plants with multifoliolate leaves is normally less than one per cent among commercial cultivars but high levels of multifoliolate leaves have been achieved through breeding.
The expression of multifoliolate leaves has been studied in white clover and it is heritable, however, there is evidence that this trait is maternally inheritance. While four leaflets is the most common multifoliolate form, there is considerable variation in this trait with up to 13 leaflets observed on an individual white clover leaf. Several multifoliolate white clovers have been sold commercially for ornamental use with Chrimson charm and Silver Sprite sold in New Zealand. The multifoliolate trait in white clover generally causes a yield reduction of between 10 and 20 per cent.