Authors:J. Zhou, W. Liu, C. Han, H. Cao, Y. Xu, W. Zhang, and Y. Yan
Wheat glutenins containing high and low molecular weight glutenin subunits (HMW-GS and LMW-GS) are the major determinants of wheat gluten quality. In this study, the recently developed reversed-phase ultra-performance liquid chromatography (RP-UPLC) was used to study the synthesis and accumulation patterns of glutenins during grain development of four Chinese bread wheat cultivars with different gluten quality. Developing grains were collected based on thermal times from 150 °Cd to 750 °Cd at 100 °Cd intervals, and the content of glutenin subunits and their accumulation patterns were determined by RP-UPLC as well as sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The results showed that HMW-GS and LMW-GS synthesis were initiated currently at 250 °Cd and they displayed a gradually upregulated expression. All the HMW-GS can be detected at 250 °Cd, earlier than LMW-GS. Different glutenin subunits and genotypes showed clear accumulation diversity during grain development. Particularly, 1Dx5 + 1Dy10 in the cultivar Gaocheng 8901 and Zhongyou 9507 with superior dough properties were accumulated faster at early stages than 1Dx2 + 1Dy12 in Jingdong 8 and Zhengmai 9023 with poor dough quality, suggesting that faster accumulation rate of glutenin proteins at the early stages of grain development may contribute to the formation of superior gluten structure and dough quality.
Ten winter wheat cultivars released in the years 1921–2003 in Slovakia were evaluated in pot experiment in 4 variants of N fertilization and in 2 terms of harvest (heading — a, maturity — m). Biomass N concentration at heading, grain N concentration (Ng), straw N concentration (Nv), and biomass N concentration at maturity were determined. N uptake and characteristics of N translocation, accumulation in grain and utilization were estimated. The year of cultivar release (YCR) was in relationships with nitrogen translocation efficiency (NTRE) (r = 0.720++) and with decreasing N% in vegetative biomass during grain filling (RNT) (r = −0.614). Strong correlation between YCR and N uptake in grain (r = 0.796), YCR and N harvest index (NHI) (r = 0.816++), and YCR and N utilization for grain (NUTg) (r = 0.877++) indicated that the modern cultivars more intensive accumulated N in grain and utilised N for grain than old ones. YCR was in negative correlation with N uptake in biomass at heading (r = −0.790++), N utilization for biomass (r = −0.678+) and with ratio Ng to Nv (relative N accumulation RNA) (r = −0.710+). Modern cultivars, in spite of their higher grain N uptake (NUP), lower N concentration in straw, higher N accumulation in grain (NHI) and higher efficiency of N translocation (NTRE) and (RNT), had lower N grain concentration than old cultivars. At the same or lower total N uptake they had considerably higher grain yield and therefore between Ng and NUTg was strong negative correlation (r = −0.977++). This is a result of the unilateral selection on grain yield. Selection should be concentrated not only on increasing of N uptake efficiency, but also on increasing of total N uptake by increasing of biomass N concentration. RNT and RNA are also recommended for selection on increasing of N grain concentration. Hypothetic models of cultivars with different NUP, NUTg and different relationships between NUTg and Ng were discussed.
Authors:Laura Ercoli, Alessandro Masoni, Marco Mariotti, and Iduna Arduini
Soil gravel content affects many soil physical properties, i.e. bulk density, porosity, water infiltration and storage, as well as crop yield. Little is known regarding the influence of soil gravel content on grain yield of durum wheat (
Desf.). In this paper the accumulation of dry matter during the vegetative and reproductive periods and the contribution of pre-anthesis assimilates to grain yield have been evaluated in two durum wheat varieties grown on soils with 0, 10, 20, and 30% gravel content. The two varieties showed similar behaviour and more soil gravel decreased plant biomass both at anthesis and at maturity. Soil gravel content greatly reduced grain yield and dry weight of all plant parts both at anthesis and maturity. Post-anthesis dry matter accumulation was 16% lower in plants grown on 30% gravel soil and dry matter remobilization was 53% lower, compared to plants grown in gravel-free soil. The differences in growth rate were attributed to the restriction of the volume of soil available for root growth.
Authors:Takashi Nakajima, Megumi Yoshida, and Naoyuki Kawada
Choo, T. M., Martin, R. A., Ho, K. M., Shen, Q., Fedak, G., Savard, M., Voldeng, H., Falk, D. E., Etienne, M., Sparry, E. 2004. Fusarium head blight and deoxynivalenol accumulation of barley in eastern Canada: Cultivar response and correlation analysis