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Csaba Lantos Jens Weyen José M. Orsini Heike Gnad Bernd Schlieter Volker Lein Stefan Kontowski Andreas Jacobi Róbert MihÁly Sue Broughton János Pauk 《Plant Breeding》2013,132(2):149-154
The efficiency of our anther culture protocol was tested with high‐ and low‐responding genotypes, ‘Svilena’ and ‘Berengar’, and 93 F1 winter wheat crosses in 2010 and 2011. Based on data for these genotypes, the effect of genotype influenced the number of embryo‐like structures, regenerated plantlets and green plantlets, while the number of albino plantlets was affected by genotype, year and environmental factors. Although genotype also influenced the production of green plantlets from breeding crosses, with green plantlets per 100 anthers ranging from 0.04 to 28.67, the average regeneration rate over all crosses was 5.3 green plantlets/100 anthers, which resulted in a total of 11 416 well‐rooted green plantlets. The survival rate of green plantlets following acclimatization was 97.21% in 2010 and 96.34% in 2011. In this study, the phenomenon of albinism and genotype dependency did not hinder the production of more than five thousand green plantlets each year. In our experiments, anther culture proved to be an efficient method in winter wheat breeding programmes with lower costs than alternative technologies. 相似文献
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Waylan AT Kayser JP Gnad DP Higgins JJ Starkey JD Sissom EK Woodworth JC Johnson BJ 《Journal of animal science》2005,83(8):1824-1831
The effects of L-carnitine on porcine fetal growth traits and the IGF system were determined. Fourth-parity sows were fed a gestation diet with either a 50-g top dress containing 0 (control, n = 6) or 100 mg of L-carnitine (n = 6). At midgestation, fetuses were removed for growth measurements, and porcine embryonic myoblasts (PEM) were isolated from semitendinosus. Real-time quantitative PCR was used to measure growth factor messenger RNA (mRNA) levels in the uterus, placenta, muscle, hepatic tissue, and cultured PEM. A treatment x day interaction (P = 0.02) was observed for maternal circulating total carnitine. Sows fed L-carnitine had a greater (P = 0.01) concentration of total carnitine at d 57 than control sows. Circulating IGF-I was not affected (P = 0.55) by treatment. Supplementing sows with L-carnitine resulted in larger (P = 0.02) litters (15.5 vs. 10.8 fetuses) without affecting litter weight (P = 0.07; 1,449.6 vs. 989.4 g) or individual fetal weight (P = 0.88) compared with controls. No treatment effect was found for muscle IGF-I (P = 0.36), IGF-II (P = 0.51), IGFBP-3 (P = 0.70), or IGFBP-5 (P = 0.51) mRNA abundance. The abundance of IGF-I (P = 0.72), IGF-II (P = 0.34), and IGFBP-3 (P = 0.99) in hepatic tissue was not influenced by treatment. Uterine IGF-I (P = 0.46), IGF-II (P = 0.40), IGFBP-3 (P = 0.29), and IGFBP-5 (P = 0.35) mRNA abundance did not differ between treatments. Placental IGF-I (P = 0.30), IGF-II (P = 0.18), IGFBP-3 (P = 0.94), and IGFBP-5 (P = 0.42) mRNA abundance did not differ between treatments. There was an effect of side of the uterus for IGF-I (P = 0.04) and IGF-II (P = 0.007) mRNA abundance; IGF-I mRNA abundance was greater in the left uterine horn than in the right uterine horn (0.14 and 0.07 relative units, respectively). Placental IGF-II mRNA abundance was greater (P = 0.007) in the left than in the right uterine horn (483.5 and 219.59, respectively). The abundance of IGFBP-3 was not affected by uterine horns in either uterine (P = 0.66) or placental (P = 0.13) tissue. There was no treatment difference for IGF-I (P = 0.31) or IGFBP-5 (P = 0.13) in PEM. The PEM isolated from sows fed L-carnitine had decreased IGF-II (P = 0.02), IGFBP-3 (P = 0.03), and myogenin (P = 0.04; 61, 59, and 67%, respectively) mRNA abundance compared with controls. These data suggest that L-carnitine supplemented to gestating sows altered the IGF system and may affect fetal growth and development. 相似文献
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Seven ruminally cannulated Holstein steers (194 +/- 16 kg) housed in metabolism crates were used in a 6 x 6 Latin square, with one additional steer, to study effects of ruminal ammonia load on methionine (Met) use. All steers received a diet based on soybean hulls (2.6 kg DM/d), ruminal infusions of 200 g/d of acetate, 200 g/d of propionate, and 50 g/d of butyrate, as well as abomasal infusion of 300 g/d of glucose to provide energy without increasing microbial protein supply, and abomasal infusions of a mixture (248 g/d) of all essential AA except Met. Treatments were arranged as a 3 x 2 factorial and included urea (0, 40, or 80 g/d) infused ruminally to supply metabolic ammonia loads and Met (2 or 5 g/d) infused abomasally. Supplementation with the greater amount of Met decreased (P < 0.05) urinary N excretion from 68.8 to 64.8 g/d and increased (P < 0.05) retained N from 22.0 to 27.5 g/d. Urea infusions linearly increased (P < 0.05) urinary N excretions, plasma urea concentrations, and urinary urea excretions, but retained N was not affected. The efficiency of deposition of supplemental Met, calculated by assuming that Met deposition is 2.0% of protein deposition (6.25 x retained N), ranged between 18 and 27% when steers received 0 or 80 g/d of urea, respectively. There were no (P > or = 0.40) effects of treatments on serum insulin or IGF-I concentrations. In our model, increasing ammonia load did not affect whole-body protein deposition in growing steers when Met was limiting. 相似文献
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Lower Cretaceous bulk carbonate from deep sea sediments records sudden inputs of strontium resulting from the exposure of continental shelves. Strontium data from an interval spanning 7 million years in the Berriasian-Valanginian imply that global sea level fluctuated about 50 meters over time scales of 200,000 to 500,000 years, which is in agreement with the Exxon sea level curve. Oxygen isotope measurements indicate that the growth of continental ice sheets caused these rapid sea level changes. If glaciation caused all the rapid sea level changes in the Cretaceous that are indicated by the Exxon curve, then an Antarctic ice sheet may have existed despite overall climatic warmth. 相似文献
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Abrupt shift in subsurface temperatures in the tropical pacific associated with changes in El Nino 总被引:1,自引:0,他引:1
Radiocarbon (14C) content of surface waters inferred from a coral record from the Galapagos Islands increased abruptly during the upwelling season (July through September) after the El Nino event of 1976. Sea-surface temperatures (SSTs) associated with the upwelling season also shifted after 1976. The synchroneity of the shift in both 14C and SST implies that the vertical thermal structure of the eastern tropical Pacific changed in 1976. This change may be responsible for the increase in frequency and intensity of El Nino events since 1976. 相似文献