The present invention provides a method for modulating or inhibiting modulation of the root architecture of a plant employing a new class of root architecture regulator (RAR) peptides, nucleotides encoding same, receptors therefor, binding agents thereof or agonists or antagonists thereof. Such methods encompass methods for increasing nutrient uptake by plants, increasing root nodule formation, promoting lateral root growth and development of plants, as well as methods for inhibiting root architecture modification resulting from root knot nematode action on plant roots. Also provided are RAR peptides, polynucleotides encoding RAR peptides and vectors and host cells comprising same, and plants obtained by methods of the invention or comprising RAR-encoding transgenes.
