John Pate's work focused on the carbon and nitrogen economy of plants, especially legumes. He analysed growth and development in terms of nitrogen and carbon fixation and pathways of nutrient circulation. His studies included: biochemistry of nitrogen fixation into amides and ureides; metabolic pathways by which these compounds are utilised, and provision of carbon skeletons for their synthesis by phloem transport from leaves; transport from root to shoot; partitioning of different classes of amino acid synthesis between leaves, stems, fruits and roots; the translocatory integration which ensures that appropriate nutritional balances reach sites of growth and sites of accumulation in developing fruits; and anatomical and cytological examination of pathways of transport.
John used these approaches to show how legumes accumulate, distribute, and utilise their metabolic resources as they grow and progress from vegetative to reproductive phases. His detailed portraits of whole plant functioning, and the concepts that have emerged, are significant for both fundamental and applied research on nitrogen fixation and plant growth and productivity.