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Objectives: Water-saving and drought-resistance rice (WDR) plays a vital role in the sustainable development of agriculture. Nevertheless, the impacts and processes of water and nitrogen on grain yield in WDR remain unclear. Methods: In this study, Hanyou 73 (WDR) and Hyou 518 (rice) were used as materials. Three kinds of nitrogen fertilizer application rate (NFAR) were set in the pot experiment, including no NFAR (nitrogen as urea applied at 0 g/pot), medium NFAR (nitrogen as urea applied at 15.6 g/pot), and high NFAR (nitrogen as urea applied at 31.2 g/pot). Two irrigation regimes, continuous flooding cultivation and water stress, were set under each NFAR. The relationships between root and shoot morphophysiology and grain yield in WDR were explored. Results: The results demonstrated the following: 1) under the same irrigation regime, the grain yield of two varieties increased with the increase of NFAR. Under the same NFAR, the reduction of irrigation amount significantly reduced the grain yield in Hyou 518 (7.1%-15.1%) but had no substantial influence on the grain yield in Hanyou 73. 2) Under the same irrigation regime, increasing the NFAR could improve the root morphophysiology (root dry weight, root oxidation activity, root bleeding rate, root total absorbing surface area, root active absorbing surface area, and zeatin + zeatin riboside contents in roots) and aboveground physiological indexes (leaf photosynthetic rate, non-structural carbohydrate accumulation in stems, and nitrate reductase activity in leaves) in two varieties. Under the same NFAR, increasing the irrigation amount could significantly increase the above indexes in Hyou 518 (except root dry weight) but has little effect on Hanyou 73. 3) Analysis of correlations revealed that the grain yield of Hyou 518 and Hanyou 73 was basically positively correlated with aboveground physiology and root morphophysiology, respectively. Conclusion: The grain yield could be maintained by water stress under medium NFAR in WDR. The improvement of root morphophysiology is a major factor for high yield under the irrigation regime and NFAR treatments in WDR.
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Seed dormancy and germination play pivotal roles in the agronomic traits of plants, and the degree of dormancy intuitively affects the yield and quality of crops in agricultural production. Seed priming is a pre-sowing seed treatment that enhances and accelerates germination, leading to improved seedling establishment. Seed priming technologies, which are designed to partially activate germination, while preventing full seed germination, have exerted a profound impact on agricultural production. Conventional seed priming relies on external priming agents, which often yield unstable results. What works for one variety might not be effective for another. Therefore, it is necessary to explore the internal factors within the metabolic pathways that influence seed physiology and germination. This review unveils the underlying mechanisms of seed metabolism and germination, the factors affecting seed dormancy and germination, as well as the current seed priming technologies that can result in stable and better germination.
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Phosphatidylserine (PS) is a major anionic phospholipid constituent of membrane bilayers, which is specifically enriched in the cytoplasmic leaflet, has functions of regulating the intracellular signaling pathways of neuronal survival and differentiation, and acts as a neurotransmitter to control the activity of neurons. Oil-in-water (O/W) emulsions could improve the bio-availability of PS. Thus, there is a high level of interest in PS emulsion because of its purported health benefits. However, because of high viscosity and poor fluidity, it remains difficult to make the emulsion. A detailed analysis with suited biophysical methods would help to better understand the processes on a molecular level. Therefore, the main aim of the present study was to engineer and characterize a stable O/W phosphatidylserine emulsion. Furthermore, the effect of emulsifiers mixture, whey protein isolate (WPI), and Tween 80 (T80), as well as the oil phase was systematically evaluated. The key parameters were the chain length and the degree of nonsaturation (sunflower oil, a long-chain triglycerides [LCTs] or a medium-chain triglycerides [MCTs]). Small droplets of emulsions could be obtained by adjusting the type of emulsifier and the LCT/MCT ratio. A stable PS emulsion characterized by a smaller droplet size, higher negative zeta-potential, lower centrifugal stability constant, and longer storage time was produced by MCTs T80 (2.0%, w/w) with T80 (2.0%, w/w) as the emulsifier, and by LCTs with the WPI (0.5%, w/w)-T80 (1.5%, w/w) as the emulsifier, respectively. The PS emulsion with LCTs exhibited higher viscosity, when compared to the emulsion made by MCT at the same emulsifier concentration, while all emulsions exhibited a shear thinning behavior. The microstructure images revealed that the PS emulsions produced by MCTs and T80 (2.0%, w/w) or WPIs (0.5%, w/w)-T80 (1.5%, w/w) mixed with LCTs can form specific uniform networks, in order to prevent flocculation. After 28 days of storage, no visual phase separation was observed in the emulsions, except for the PS emulsion with the WPI (2.0%, w/w). It was concluded that the characteristics of the interfacial layer of particles in the PS emulsion system were not only dependent on the proportion of the applied emulsifiers, but also dependent on the oily phase features. These findings may provide indications for choosing the suitable process parameters when a stable PS emulsion is produced.
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BACKGROUND: The improvement of rice cultivars plays an important role in yield increase. However, little is known about the changes in starch quality and mineral elements during the improvement of rice cultivars. This study was conducted to investigate the changes in starch quality and mineral elements in japonica rice cultivars. RESULTS: Twelve typical rice cultivars, applied in the production in Jiangsu province during the last 60 years, were grown in the paddy fields. These cultivars were classified into six types according to their application times, plant types and genotypes. The nitrogen (N), phosphorus (P) and, and potassium (K) were mainly distributed in endosperm, bran and bran, respectively. Secondary and micromineral nutrients were distributed throughout grains. With the improvement of cultivars, total N contents gradually decreased, while total P, K and magnesium contents increased in grains. Total copper and zinc contents in type 80'S in grains were highest. The improvement of cultivars enhanced palatability (better gelatinisation enthalpy and amylose content), taste (better protein content) and protein quality (better protein components and essential amino acids). Correlation analysis indicated the close relationship between mineral elements and starch quality. CONCLUSION: The mineral elements and starch quality of grains during the improvement of japonica rice cultivars are improved. © 2017 Society of Chemical Industry.
