Effect of N fertilizer application on apex development of different tiller positions at different spike development stages

Nitrogen nutrition is one of the important factors which impact apex development in wheat It was found that the treatments of applying nitrogen fertilizer at glum (N1), pistil(N2) and anther (N3) differentiation stages, respectively, had no effect on the leaf primordium number on main stem (MS) and spikelet numbers on MS, T1 and T2 (the first and second tillers on MS) Compared with N0 (no N fertilizer applied in spring), the treatments of N1, N2 and N3 enhanced the rate of leaf emergence on MS and lessened the infertile spikelets on MS, T1, T2 and T3 The treatments of N1 and N2 improved the floret primordium differentiation, which resulted in more florets on MS, T1, T2 and T3 Also, applying N fertilizer from grum to anther differentiation stage could enhance evidently the grain setting rate of florets on MS, T1, T2 and T3 The results will help the cultural regulation and growth simulation in high yielding wheat.