Effect of deficit irrigation scheduling and planting pattern on leaf water status and radiation use efficiency of winter wheat

Drought and water shortages have always been great challenges for agricultural production in the North China Plain. To explore appropriate irrigation regimes and planting patterns in this area, a field experiment was conducted for winter wheat (Triticum aestivum L.) from 2014 to 2016. Three irrigation treatments of 50 mm irrigation at growth stage of jointing (GS34) and heading (GS48, W1), 100 mm irrigation at GS34 (W2) and 100 mm irrigation at GS34 and GS48 (W3) combined with uniform (U), double-double (DD) and furrow-ridge (F) planting patterns were designed. The tillers number, leaf water status, spike characteristics and radiation use efficiency (RUE) were measured. Results showed that compared with W2, W3 significantly reduced leaf abscisic acid (ABA) content and increased tillers number, spikelets spike(-1), yield components and RUE, while W1 produced more tillers number, leaf relative water content (LRWC) and water potential (L psi) only in the late growth stage, yield components and RUE. The DD significantly increased tillers number, LRWC, L psi, leaf osmotic potential, spike length, spikes m(-2), grains spike(-1) and RUE, and reduced the ABA content compared with U. Considering the serious water shortage in the North China Plain, 50 mm irrigation at jointing and heading stages combined with DD is a worthy cultivation measure for sustainable agriculture at water-deficit condition.