Control of Wheat Stripe Rust and Ensuring High Yield of Crops under Planting of Wheat Variety Mixtures

Wheat stripe rust has become the most dangerous disease which threaten safe yield of wheat in Sichuan Province. It is meaningful to provide technique support for integrated disease control by exploring the effective control measures of wheat stripe rust. Wheat stripe rust dynamic developments of all-planting and mixed-planting have been systematically investigated in this study by taking different mixed-planting combinations among 6 wheat varieties with different resistance levels. The results of this experiment show that the mixed-plantings of 4 and 6 wheat varieties can delay the occurance of wheat stripe rust,slow the speed of disease and decline the damage of disease as well as stabilize yield of wheats.

Wheat Grain Yield and Yield Stability in a Long-Term Fertilization Experiment on the Loess Plateau

To provide a scientific basis for sustainable land management, a 20-year fertility experiment was conducted in Changwu County, Shaanxi Province, China to investigate the effects of long-term application of chemical fertilizers on wheat grain yield and yield stability on the Loess Plateau using regression and stability analysis. The experiment consisted of 17 fertilizer treatments, containing the combinations of different N and P levels, with three replications arranged in a randomized complete block design. Nitrogen fertilizer was applied as urea, and P was applied as calcium superphosphate. Fertilizer rates had a large effect on the response of wheat yield to fertilization. Phosphorus, combined with N, increased yield significantly （P 〈 0.01）. In the unfertilized control and the N or P sole application treatments, wheat yield had a declining trend although it was not statistically significant. Stability analysis combined with the trend analysis indicated that integrated use of fertilizer N and P was better than their sole application in increasing and sustaining the productivity of rainfed winter wheat.

Effect of Malva Nut Gum on Pasting Characteristics and Freeze-thaw Stability of Commercial Wheat, Rice or Waxy Rice Flour

The objective of this research was to investigate the effect of Malva nut gum （MG） replacement on the pasting characteristics and freeze-thaw stability of wheat, rice or waxy rice flours. Pasting properties and freeze-thaw stability of different flours incorporated with 0, 0.5%, 1%, 2%, 3% and 5% of MG were investigated. Pasting temperature （60 ℃-87 ℃） of the pastes significantly decreased with increasing of MG content for wheat and rice flours, but had no significant effect for waxy rice flour. Incorporation of MG into all flours significantly elevated the peak viscosity by about 0.9-2.6 folds when compared to non-MG samples. Hot paste viscosity, breakdown and final viscosity for all flour mixtures significantly increased with increasing of MG which ranged from 81-427, 37-559 and 152-463 RVU, respectively. Freeze-thaw stability measurement demonstrated that higher level of MG in wheat and rice gel mixtures could decrease syneresis. However, MG had no effect on syneresis of waxy rice gel. Presence of MG in flours alters the pasting properties and syneresis effect. It is suggested that higher viscosity and lower syneresis of gels could be modified by MG.

Effect of Storage Temperature on Sensory and Physicochemical Properties of Wheat Flour Fortified with Elevated Levels of Vitamin A in Combination with Three Types of Iron

Many persons worldwide are deficient in micronutrients, two of the most common being vitamin A and iron. Fortification of staple food is a commonly used and effective method of boosting micronutrient intake. Wheat flour is widely used around the world and makes a good vehicle for fortification, but there is a lack of studies on the storage stability of fortified wheat flour. In this study, we fortified wheat flour with elevated levels of vitamin A and three sources of iron and stored it for up to 16 weeks at refrigerated or room temperature or elevated temperature. The rate of disappearance of vitamin A was monitored by high pressure liquid chromatography, and the rate of disappearance was fotmd to be directly proportional to the duration of storage and storage temperature. Higher temperatures contributed to greater loss of vitamin A. Iron, regardless of source, did not play a major role in contributing to the rate of vitamin A loss. Flour functionality was assessed by baking loaves of bread from the stored flour and assessing physical properties as well as subjecting the loaves to an expert sensory panel. Functionality also changed with time and temperature of storage, but sensory analysis found that these changes were not detrimental to the quality of bread baked from the stored flours. Trained sensory panelists found that breads baked from flours fortified with ferrous sulfate and stored at the three temperatures for times up to eight weeks were markedly different from fortified flours using hydrogen reduced irons.

回族形成的历史人类学解读

本文从历史人类学的角度对回族的形成进行了分析,提出回族的形成过程是基于共享的“既定资赋”,即以Ummah为民族文化范式,在汉文化的宏观语境下,在与不同族群交往、对比以及国家认同与民族认同的互动和重构的综合作用下形成了民族。

Variation in β-amylase activity and thermostability in Tibetan annual wild and cultivated barley genotypes

13-Amylase activity （BAA） and thermostability （BAT） are important traits for malt quality. In this study, 138 Tibetan annual wild barley accessions and 20 cultivated genotypes differing in BAh, were planted and analyzed in 2009 and 2012. Significant differences were detected among genotypes in BAA and BAT. The cultivated genotypes had a mean BAA of 1137.6 U/g and a range of from 602.1 to 1407.5 U/g, while the wild accessions had a mean of 1517.9 U/g and a range of from 829.7 to 2310.0 U/g. The cultivated genotypes had a mean relative residual 13-amylase activity （RRBAA） of 61.6% and a range of from 22.2% to 82.3%, while the wild barleys had a mean of 57.8% and a range of from 21.9% to 96.1%. Moreover, there was a significant difference among genotypes in the response of RRBAA to the temperature and duration of heat treatment. The wild barleys had wider variation in BAA and BAT than cultivated genotvDes.

Dirac Quasinormal Modes of Static f(R) de Sitter Black Holes

Quasinormal modes （QNMs） for Dirac perturbations off（R） black holes （BHs） are described in this paper, involving two types of f（R） solution： f（R） （Sehwarzschild） BHs and f（R） （Maxwell） BHs. With the finite difference method, the stability of the f（R） black holes （BHs） is analysed and the threshold range off（R） （Schwarzschild） BHs and f（R） （Maxwell） BHs is defined respectively. The results show that due to the presence of the correction factor Ro, the damping rate of Dirac field decreases. Meanwhile, the influence of angular quantum number values [k] on the f（R） BHs is investigated. The results indicate that the QNMs oscillation becomes tenser and damping speed slowly decreases with ]k[ increasing. Furthermore, under the Dirac perturbation, the stability off（R） solutions can be reflected in the manner of Dirac QNMs. The relationships between the QNMs and the parameters （]k], charge Q and mass m） are discussed in massless, and massive cases, by contrast to the classical BHs.

Collisional Efect on Weibel Instability with Semi-Relativistic Maxwellian Distribution Function

In this paper, the Coulomb collisional effect of electron-ion on the growth rate of Weibel instability is investigated based on the semi-relativistic Maxwellian distribution function in dense and unmagnetized plasma. An analytical expression was derived for the dispersion relation of Weibel instability for two limit cases [ξ = ω＇/k‖T‖ 〉〉 1 and ｜ξ｜ 〈〈 1. In limit ｜ξ｜ 〉〉 1 the dispersion relation only includes a real part and in limit ｜ξ｜ 〈〈 1 the imaginary part of the frequency of waves＇ instability plays a role in the dispersion relation. In limit ｜ξ｜ 〈〈 1, the two quantities μ and η, that are due to the relativistic and collisional effects, will appear in the growth rate of Weibel instability. The growth rate of Weible istability will be increased through decreasing the Coulomb collisional frequency and also increasing the temperature anisotropic parameter in strong relativistic limit.