Biomass accumulation and radiation use efficiency of winter wheat under deficit irrigation regimes

Abstract

ABSTRACTto better understand the potential for improving biomass accumulation and radiation use efficiency (rUE) of winter wheat under deficit irrigation regimes, in 2006-2007 and 2007-2008, an experiment was conducted at the luancheng Experimental Station of Chinese academy of Science to study the effects of deficit irrigation regimes on the photosynthetic active radiation (Par), biomass accumulation, grain yield, and rUE of winter wheat. in this experiment, field experiment involving winter wheat with 1, 2 and 3 irrigation applications at sowing, jointing, or heading stages was conducted, and total irrigation water was all controlled at 120 mm. The results indicate that irrigation 2 or 3 times could help to increase the Par capture ratio in the later growing season of winter wheat; this result was mainly due to the changes in the vertical distributions of leaf area index (lai) and a significant increase of the lai at 0-20 cm above the ground surface (lSD, P < 0.05). Compared with irrigation only once during the growing season of winter wheat, irrigation 2 times significantly (lSD, P < 0.05) increased aboveground dry matter at maturity; irrigation at sowing and heading or jointing and heading stages significantly (lSD, P < 0.05) improved the grain yield, and irrigation at jointing and heading stages provided the highest rUE (0.56 g/mol). Combining the grain yield and rUE, it can be concluded that irrigation at jointing and heading stages has higher grain yield and rUE, which will offer a sound measurement for developing deficit irrigation regimes in north China.

The Evaluation of Radiation Use Efficiency and Leaf Area Index Development for the Estimation of Biomass Accumulation in Short Rotation Poplar and Annual Field Crops

“…In earlier studies, AGDMs of 5.6 t ha −1 for barley in Pakistan [64] and 10.3-14.2 t ha −1 in the USA [22] were observed, for wheat 5.3-6.7 t ha −1 in China [79] and 5.74-7.22 t ha −1 in Pakistan [64], for maize 14.5-14.9 t ha −1 in different water regimes for many years in China [80], and for oilseed rape 3.6-4.7 t ha −1 for many cultivars in the Czech Republic and other European countries [90] which is in accordance with our data.…”

“…It may be due to differences in crop physiology [12,75] and nutrient effects [64,76] as the effect of nutrition (particularly N) increases RUE. RUE is increased by higher N doses [16,77] and can be stimulated also by a higher availability of P and K [78][79][80]. Higher RUE is often reported also for C 4 crops, but the differences in crop physiology depend greatly on environmental conditions, particularly temperature [25,81].…”

Effect of different supplemental irrigation strategies on photosynthetic characteristics and water use efficiency of wheat

“…In this scheme, 60-75 mm irrigation water is used two to three times at key growing stages (jointing, booting, flowering, and milking stages) of wheat (Li et al, 2009;Zhao et al, 2013;Wang et al, 2014a). Quota SI with 60 mm water per time at jointing and heading stages is commonly employed in North China Plain (Li et al, 2009). However, there are some limitations in these studies, as they did not consider the effect of soil water conditions before irrigation on the irrigation amount, water consumption and wheat production.…”

Effect of Irrigation to Winter Wheat on the Radiation Use Efficiency and Yield of Summer Maize in a Double Cropping System

“…Evapotranspiration during the winter wheat growing season is approximately 400–500 mm, but annual precipitation typically does not exceeded 200 mm [3, 4]. Therefore, additional irrigation is required to achieve a satisfactory winter wheat grain yield.…”