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Amylose content controlled by Wx determines rice grain quality, which is easily affected by high temperature. Wxa and Wxb are the two typical Wx alleles in rice, however, their effects on quality formation in response to high temperature under the backgrounds of indica rice and japonica rice have not been systematically compared. In this study, the near-isogenic lines (NILs) of Wxa and Wxb with japonica rice 2661 and indica rice 3611 backgrounds were treated by high temperature during the grain-filling stages. High temperature accelerated the grain ripening process, decreased the thousand-kernel weight, and increased the chalkiness degree of all rice samples. However, these traits of Wx NILs with 3611 background were more susceptible to high temperature than those with 2661 background. Furthermore, high-temperature treatment decreased the amylose contents (AC) and starch viscosities but increased the gelatinization temperature of all the Wx NILs. The 3611-Wxa was atypical Wxa-type rice, whose AC was more sensitive to high temperature. The AC result was consistent with quantitative analysis of GBSSI by Western blot. In addition, the effects of Wx genotype and genetic background on rice physicochemical quality (such as the gel consistencies, starch crystallinity, and the morphological structure of starch grains) in response to high temperature were systematically analyzed. These results have important guiding significance for rice-quality improvement under high-temperature climate. [ABSTRACT FROM AUTHOR]

In this paper, the effects of asymmetrically modulated charged surfaces on streaming potential, velocity field and flow rate are investigated under the axial pressure gradient and vertical magnetic field. In a parallel-plate microchannel, modulated charged potentials on the walls are depicted by the cosine function. The flow of incompressible Newtonian fluid is two-dimensional due to the modulated charged surfaces. Considering the Debye–Hückel approximation, the Poisson–Boltzmann (PB) equation and the modified Navier-Stokes (N-S) equation are established. The analytical solutions of the potential and velocities (u and v) are obtained by means of the superposition principle and stream function. The unknown streaming potential is determined by the condition that the net ionic current is zero. Finally, the influences of pertinent dimensionless parameters (modulated potential parameters, Hartmann number and slip length) on the flow field, streaming potential, velocity field and flow rate are discussed graphically. During the flow process and under the impact of the charge-modulated potentials, the velocity profiles present an oscillating characteristic, and vortexes are generated. The results show that the charge-modulated potentials are beneficial for the enhancement of the streaming potential, velocity and flow rate, which also facilitate the mixing of fluids. Meanwhile, the flow rate can be controlled through the use of a low-amplitude magnetic field. [ABSTRACT FROM AUTHOR]