Dry Matter Production, Photosynthesis of Flag Leaves and Water Use in Winter Wheat Are Affected by Supplemental Irrigation in the Huang-Huai-Hai Plain of China

Abstract

Winter wheat is threatened by drought in the Huang-Huai-Hai Plain of China, thus, effective water-saving irrigation practices are urgently required to maintain its high winter wheat production. This study was conducted from 2012 to 2014 to determine how supplemental irrigation (SI) affected soil moisture, photosynthesis, and dry matter (DM) production of winter wheat by measuring the moisture in 0–20 cm (W2), 0–40 cm (W3), and 0–60 cm (W4) soil profiles. Rainfed (W0) and local SI practice (W1, irrigation with 60 mm each at jointing and anthesis) treatments were designed as controls. The irrigation amount for W3 was significantly lower than that for W1 and W4 but higher than that for W2. The soil relative water content (SRWC) in 0–40 cm soil profiles at jointing after SI for W3 was significantly lower than that for W1 and W4 but higher than that for W2. W3 exhibited lower SRWC in 100–140 and 60–140 cm soil profiles at anthesis after SI and at maturity, respectively, but higher root length density in 60–100 cm soil profiles than W1, W2 and W4. Compared with W1, W2 and W4, photosynthetic and transpiration rates and stomatal conductance of flag leaves for W3 were significantly greater during grain filling, particularly at the mid and later stages. The total DM at maturity, DM in grain and leaves, post-anthesis DM accumulation and its contribution to grain and grain filling duration were higher for W3. The 1000-grain weight, grain yield and water use efficiency for W3 were the highest. Therefore, treatment of increasing SRWC in the 0–40 cm soil profiles to 65% and 70% field capacities at jointing and anthesis (W3), respectively, created a suitable soil moisture environment for winter wheat production, which could be considered as a high yield and water-saving treatment in Huang-Huai-Hai Plain, China.

Biomass production and characteristics of short rotation plantations of clones of Gmelina arborea in three spacings

“…There is hardly any rainfall between January and the first week of May (Moya and Tomazello, 2008). During the first year, the biomass flow seems to be uninfluenced by precipitation, due to the dry period (Man et al, 2015). In this trial, a slight inflection point or change in the trend occurred in leaf fall during the dry months (March to May) of the first year in all spacings (Figure 4a-c).…”

Influence of water deficit on photosynthetic activity, dry matter partitioning and grain yield of different durum and bread wheat genotypes

“…Despite the fact that wheat genotypes with high P n , g s and E are more sensitive to drought, such advantage plays a role in stabilizing the productivity under drought. Higher photosynthesis rate, especially at the mid and later grain filling stages, promotes post-anthesis dry matter accumulation and grain filling (Man et al 2015). A positive association of P n with growth rate of wheat genotypes was revealed.…”

The effect of different post-anthesis water supply on the carbon isotope discrimination of winter wheat grain

“…The differentiated water supply after flowering was significant (P < 0.01) in both experiments in spite of the same water supply treatments during grain growth. As a significant part of grain carbon comes from the reutilization and redistribution of C-substances produced during pre-anthesis growth (e.g., Man et al 2015), the effect was probably caused by the differential availability of water (precipitation, soil supply) before grain formation, resulting in different 13 C discrimination. It was confirmed by the low grain Δ 13 C of all treatments (16-18.7‰) in exceptionally dry year 2007.…”