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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 aestivumL.). 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 F3generation 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‐mssystem of producing hybrid wheat.

Abstract The change in cytosolic free concentration of calcium ([Ca2+]cyt) plays a key role in regulating apoptosis in animal cells. In our experiment, we tried to investigate the function of Ca2+ in programmed cell death (PCD) in tobacco (Nicotiana tobacum, cultivar BY-2) protoplasts induced by salt stress. An obvious increase in [Ca2+]cyt was observed a few minutes after treatment and the onset of a decrease in mitochondrial membrane potential (??m) was also observed before the appearance of PCD, pre-treatment of protoplasts with EGTA or LaCl3 effectively retarded the increase in [Ca2+]cyt, which was concomitant with the decrease in the percentage of cell death and higher ??m, pre-treatment with cyclosporine A (CsA) also effectively retarded the increase in [Ca2+]cyt, the decrease in ??m and the onset of PCD. All these results suggest that Ca2+ is a necessary element in regulating PCD and the increase in [Ca2+]cyt and the opening of mitochondrial permeability transition pore (MPTP) could promote each other in regulating PCD in tobacco protoplasts induced by salt stress.

The impacts of elevated CO2and soil water on the population dynamics, adult fecundity and nymphal period of the bird cherry-oat aphidRhopalsiphum padi(Linnaeus) were evaluated in three experiments: (i)Combined effects of CO2and soil water on aphid populations. Spring wheat was grown in pots at three CO2concentrations (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 CO2concentrations 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 CO2and soil water levels. (iii)Direct effects of CO2concentrations 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 CO2concentrations. It was found that the direct effect of CO2concentration on aphid population parameters was minor. CO2and soil water affected aphid population indirectly through their effects on wheat characteristics. The aphid population under 550 ppm CO2was far larger than the one under 350 ppm CO2, whereas the population under 700 ppm CO2was slightly higher than that under 550 ppm CO2. The largest aphid population was obtained with the 60% soil water treatment, regardless of CO2treatment. The effects of CO2concentration on aphid population were, however, not significantly correlated with soil water level. Adult fecundity increased with CO2concentration, the highest fecundity being achieved under 60% FWC treatments. The nymphal period was not affected by CO2concentration. The shortest period occurred under 60% FWC. Atmospheric CO2and 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.