Nitrogen Translocation in Wheat Plants Under Soil Water Deficit

Abstract

Accumulation and translocation of nitrogen (N) in the vegetative organs and grains of winter wheat (Triticum aestivum L.) are important processes in determining yield and quality. The present study was conducted to compare the effects of water deficit and cultivars (cv. Lumai 21 and Jinan 17) on N translocation from vegetative organs to grains in a mobile rain-shelter using 15 N-labeled ammonium sulfate fertilizer. The N translocation amounts (defined as the difference between the N amount at anthesis and the N amount at maturity for a vegetative organ) in leaves were greatest for the two cultivars, followed by glumes, stems, and sheaths, respectively. The N translocation ratio (defined as the ratio of the translocation amount to N amount at anthesis) in total above-ground parts were greater for Lumai 21 (0.65 g g )1 DW) than for Jinan 17 (0.60 g g )1 DW), and Lumai 21 plants had a higher N translocation ratio for the N derived from fertilizers. The N contribution (defined as the ratio of the translocation amount to grain N amount) of total vegetative parts aboveground to grain N ranged from 0.50 to 0.77 g g )1 DW, and that of the leaf was the greatest. The results showed that water deficit remarkably increased the N translocation ratio derived from soil and the contributions of N in various vegetative organs to grain N. It is suggested that water deficit would weaken the availability of fertilizer N but enhance the remobilization of prestored N to the grains.

Effects of Varieties and Nitrogen Fertilizer on Yield and Yield Components of Maize on Farmers Field in Mid Altitude Areas of Western Ethiopia

“…The N harvest index (NHI) at maturity was calculated by Jones et al [31] and N accumulation (kg N ha −1 ) in the shoots or grains was calculated by Seleiman et al [32] and Xu et al [33] as follows:…”

Nitrogen and Water Utilization Efficiency of Barley Subjected To Desiccated Conditions in Moderately Salt-Affected Soil

“…It seems that water deficit limited contribution of current photosynthesis in formation of grain yield and straw yield. On the other hand, Xu et al (2006) proved that the N translocation amount of total above-parts for N from the soil significantly increased at water deficit. Table 6 showed that a significant (p < 0.05) effect of N levels in both seasons.…”

“…N absorbed from soil and translocated from plant stem and leaves to grain filling is affected by the amount of water applied into the crop (Clarke et al, 1990). Water shortage substantially can increase the N translocation divided from soil and the contributions of N in different vegetative organs to grain N uptake, although it can reduce the availability of N to the plants (Xu et al, 2006). The DM translocation at heading and also N translocation were related to N content at heading (Pampana et al, 2007).…”

Deficit Irrigation of Durum Wheat (Triticum durum Desf): Effects on Total Dry Matter Production, Light Interception and Radiation Use Efficiency Under Different Nitrogen Rates

“…Higher rates of N may shift the balance between vegetative and reproductive growth toward excessive vegetative development, thus delaying crop maturity and reducing final yield (Howard et al, 2001;Hamzei, 2011). Water deficit remarkably decreases the nitrogen translocation ratio derived from soil and adversely affects the contributions of nitrogen in various vegetative organs to grain nitrogen (Xu et al, 2006;Hamzei, 2011). Several water-saving methods have been developed (Belder et al, 2004;Bouman et al, 2006), among which, deficit irrigation is one of the best techniques that could improve irrigation water use.…”