Temporal origin of nitrogen in the grain of irrigated rice in the dry season: the outcome of uptake, cycling, senescence and competition studied using a -point placement technique

It is often suggested that nitrogen absorbed in the vegetative stage of growth acts as a ‘reservoir’ to supply the shortfall in demand during grain filling. The main objective of the work described in this paper was to investigate how effectively nitrogen absorbed at different stages of the growing season was retained and used for grain growth. The total nitrogen in the grain is the integral of the product of the total nitrogen absorbed at any...