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A cytogenetic method for producing hybrid seed using a nuclear gene for male sterility and an alien chromosome to obtain a pollination control system has been proposed in bread wheat (Triticum aestivum L.). Our objective was to transfer the alien chromosome 4E to the monogenic recessive male-sterile mutant Lanzhou (LZ), and then to establish an efficient cytogenetic system of maintaining the male sterility of the LZ mutant. After crossing the 4E disomic addition line 81529 (2n 44) as male to LZ [2n = 42(msms) = 42], we obtained the 4E monosomic addition line [2n 43(msms)] in the F3 generation that had light-blue seed color. The line was homozygous for the male-sterile gene (msms) of the host wheat and also had good self-fertility. The self-fertilized seeds segregated into 64.3% white (nonblue) with genotype 2n = 42(msms), 32.1% light blue with genotype 2n = 43(msms) and 3.6% deep blue with genotype 2n = 44(msms) grains. All plants grown from the white grains were completely male sterile. All plants grown from the light-blue grains had good self-fertility whose progeny seeds segregated into white, light-blue, and deep-blue grains again in succeeding generations. All plants grown from the deep-blue grains were self-fertile and retained their deep-blue color in the succeeding generations. When white grain male-sterile lines were crossed using any cultivar as the male parent, the hybrid plants had male fertility restored. And, this is the basis for the 4E-ms system of producing hybrid wheat., THERE HAVE BEEN many reports of genetic male sterilty (GMS) of wheat in the literature. Five GMS loci have been located to chromosomes so far. These loci are msl, a [...]

The impacts of elevated CO2 and soil water on the population dynamics, adult fecundity and nymphal period of the bird cherry-oat aphid Rhopalsiphum padi (Linnaeus) were evaluated in three experiments: (i) Combined effects of CO 2 and soil water on aphid populations. Spring wheat was grown in pots at three CO2 concentrations (350, 550 and 700 ppm) and three soil water levels (40%, 60% and 80% of field water capacity, FWC) in field open-top chambers (OTC) and infested with the bird cherry-oat aphid. Aphid population dynamics were recorded throughout the growing season; at the same time, adult fecundity and duration of the nymphal period were recorded. Chemical composition of spring wheat leaves was also analyzed. (ii) Indirect effects of CO 2 concentrations and soil water on aphid adult fecundity and nymphal period. The experiment was conducted with the leaf discs method in the laboratory. Aphids were reared on leaf discs excised from the treated wheat in OTC with different CO2 and soil water levels. (iii) Direct effects of CO 2 concentrations on aphid adult fecundity and nymphal period. Aphids were reared on leaf discs excised from the wheat grown under natural conditions. The experiment was conducted with the leaf disc method in OTC with the three CO2 concentrations. It was found that the direct effect of CO2 concentration on aphid population parameters was minor. CO2 and soil water affected aphid population indirectly through their effects on wheat characteristics. The aphid population under 550 ppm CO2 was far larger than the one under 350 ppm CO2, whereas the population under 700 ppm CO2 was slightly higher than that under 550 ppm CO2. The largest aphid population was obtained with the 60% soil water treatment, regardless of CO2 treatment. The effects of CO2 concentration on aphid population were, however, not significantly correlated with soil water level. Adult fecundity increased with CO2 concentration, the highest fecundity being achieved under 60% FWC treatments. The nymphal period was not affected by CO2 concentration. The shortest period occurred under 60% FWC. Atmospheric CO2 and soil water had significant effects on the chemical composition of the wheat leaves. Aphid population size was positively correlated with leaf water content, concentrations of soluble proteins, soluble carbohydrates and starch, and negatively correlated with DIMBOA and tannins concentrations. [ABSTRACT FROM AUTHOR]

Sugars act as vital signaling molecules that regulate plant growth, development and stress responses. However, the effects of sugars on stomatal movement have been unclear. In our study, we explored the effects of monosaccharides such as glucose and mannose on stomatal aperture. Here, we demonstrate that glucose and mannose trigger stomatal closure in a dose- and time-dependent manner in epidermal peels of broad bean (Vicia faba). Pharmacological studies revealed that glucose- and mannose-induced stomatal closure was almost completely inhibited by two reactive oxygen species (ROS) scavengers, catalase (CAT) and reduced glutathione (GSH), was significantly abolished by an NADPH oxidase inhibitor, diphenylene iodonium chloride (DPI), whereas they were hardly affected by a peroxidase inhibitor, salicylhydroxamic acid (SHAM). Furthermore, glucose- and mannose-induced stomatal closure was strongly inhibited by a Ca(2+) channel blocker, LaCl3 , a Ca(2+) chelator, ethyleneglycol-bis(beta-aminoethylether)-N,N'-tetraacetic acid (EGTA) and two water channel blockers, HgCl2 and dimethyl sulfoxide (DMSO); whereas the inhibitory effects of the water channel blockers were essentially abolished by the reversing agent β-mercaptoethanol (β-ME). These results suggest that ROS production mainly via NADPH oxidases, Ca(2+) and water channels are involved in glucose- and mannose-induced stomatal closure., (© 2015 Scandinavian Plant Physiology Society.)

According to plant modular theory, the Yoda's-3/2 law of self-thinning was theoretically rederived in this paper. With the parameters in the expression of Yoda's-3/2 law being given biological meanings, this article offered universal and rational explanations for relevant data in literatures that could not be explained before. Based on the authors' hypothesis, the experiments on the self-thinning process of spring wheat (Triticum aestivum L.) were conducted. Individual morphological and population quantitative indexes were examined at regular intervals. The results showed that the self-thinning process of spring wheat conformed to Yoda's-3/2 law of self-thinning. At the same time, the universality of Yoda's-3/2 law of self-thinning was explained theoretically by analyzing individual morphological data.

The effects of drought, CO2 concentration and temperature increasing on development period, photosynthesis rate (Pn), evapotranspiration (ET), and water use efficiency of spring wheat were investigated. The results showed that elevated CO2 concentration (550, 700 mumol.mol-1) could lengthen heading-ripening period, but high temperature (average diurnal temperature increase 4.8 degrees C), which made heading-ripening period shorten and speeded the seedling under treatment of both high CO2 concentration and high temperature, affected growing period more than high CO2 concentration. The combined effects of elevated CO2 concentration and temperature enhanced Pn, stomatal resistance (r), leaf water use efficiency (WUEl), and whole-canopy water use efficiency (WUE), while transpiration rate (E) were not significantly affected. The effects on ET depended on soil moisture. High CO2 concentration and high temperature enhanced ET under high (75%-85% field water capacity) and middle (55%-65% field water capacity) soil moisture, but decrease ET under low soil moisture (35%-45% field water capacity).