Transfer of nitrogen between clover and wheat: Effect of root herbivory

The extent to which larvae of the root feeding insect, Sitona lepidus, affe cts the transfer of N from clover to associated wheat plants in soil system s is assessed in this paper. White clover (Trifolium repens) plants were gr own from seed in a nutrient solution containing 99.99 atom % (NH3NO3)-N-14- N-14 as the N-source. Individual clover plants were transferred to pots con taining sieved field soil. A single wheat (Triticum arvense) seed was plant ed with the clover plant and allowed to develop for 47 d. The pots were eit her infested with insect larvae or uninfested. The presence of the insect l arvae in the pots significantly reduced clover dry matter and it was calcul ated that 7 % of the N in the wheat plants originated from clover. (C) Else vier, Paris.