Correlated effects of exotic pollen‐fertility restorer genes on agronomic and quality traits of hybrid rye

In CMS (cytoplasmic male sterility)‐based hybrid rye (Secale cereale L.) breeding, effective pollen‐fertility restoration is an essential prerequisite for achieving maximum grain yield on the one hand and for minimizing ergot (Claviceps purpurea) infestation on the other. Restorer genes for the CMS‐inducing ‘Pampa’ cytoplasm derived from landraces collected in Iran and Argentina are used by breeders for achieving this goal. Here, restorer genes from four germplasm sources (‘Altevogt 14160’, ‘IRAN III’, ‘Trenelense’ and ‘Pico Gentario’) were analysed by producing three‐way cross hybrids between an elite CMS single cross and pollinators with and without a given restorer gene. Materials were evaluated on large drilled plots for restorer index (RI), grain yield, plant height and other traits in six environments. In experiment 1, a restorer gene from ‘Altevogt 14160’ was used. Seven pairs of marker‐selected carrier and non‐carrier backcross lines served as pollinators. In experiment 2, the pollinators were 17 backcross line pairs from the other three germplasm sources. These lines were grouped as high (RI > 67%) and low restorers (RI < 30%), respectively, using testcrosses with a highly diagnostic CMS tester. Hybrids carrying an exotic restorer gene suffered from a significant grain yield reduction by 4.4% and 9.4% and were 9.3 and 4.8 cm taller in experiments 1 and 2, respectively. Thousand‐kernel weight was reduced, whereas quality traits were only slightly affected. For all traits, significant genetic variance existed among the testcrosses to the presence vs. absence of a given exotic restorer gene. This offers a chance for the breeder to reduce or ultimately overcome the presently observed performance reductions brought about by exotic restorer genes.     

草坪的生态景观研究

对西安、杨陵等市区城市生态景观中草坪的调查研究结果表明，草坪能够起到降低温度、调节湿度的作用，有一定的杀菌滞尘作用，且对周围环境的影响在一定的范围内，种植配置方式不同，有不同的影响效果。     

Novobiocin Inhibits Both UDP-Glucuronosyltransferase and Cytochrome P450-Mediated Enzyme Activities in Pig Liver Microsomes

The effects of novobiocin (range 0.0125–2 mmol/L) on the hydroxylation of testosterone, the N-demethylation of erythromycin, and the glucuronidation of -naphthol and paracetamol were studied using pig hepatic microsomes, pooled from five animals. The final concentrations of these substrates in the incubation mixtures were selected to meet V_max conditions. Novobiocin caused a concentration-dependent inhibition of the glucuronidation of paracetamol; the formation of -naphthol-glucuronide was reduced to a lesser degree. These results confirm and extend earlier findings in laboratory animal species that novobiocin inhibits UDP-glucuronosyltransferases (UDPGTs). Moreover, novobiocin strongly inhibited 6-hydroxylation of testosterone. The microsomal N-demethylation of erythromycin and hydroxylation of testosterone at the 15 position were less affected by novobiocin. These results suggest that novobiocin inhibits not only UDPGTs, but also cytochrome P450 (CYP) enzyme activities, probably those belonging to the CYP3A subfamily. More research is needed to reveal which CYPs and UDPGTs are affected by novobiocin in vivo, in order to improve the understanding and probably the predictability of potential drug interactions with this antibiotic.     

Lactobacilli Improve the Antioxidant Activity in Fermented Coriolus versicolor Extract

Coriolus versicolor has been reported to have biological activities such as anticancer, antibacterial, antibiotics and immunopotentiation. The authors tried to ferment using lactobacilli associated with various biological functions and expected that fermented extract by lactobacilli will be superior to non-fermented extract in antioxidant activity. C. versicolor was extracted with 70% ethanol and then it was fermented by Lactobacillus acidophilus KCTC3164 and Lactobacillus plantarum KCTC3099, respectively. 1,l-dipheny｜-2-picrylhydrazyl （DPPH） scavenging activity, superoxide dismutase （SOD）-like activity and tetrazolium salt 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide （MTT） assays were performed. DPPH scavenging activity of fermented extract by L. acidophilus was higher than fermented extract by L. plantarum and antioxidant effect of fermented extract was 20%-30% higher than non-fermented extract. SOD-like activity was represented 18% in fermented extract by L. acidophilus, and was 27% in fermented extract by L. plantarum higher than non-fermented extract. As a result, this study suggests that it may need an efficient protocol for dominant bio-physiological activities such as extract volume or appropriate working volume of cultured cell or mixture condition. The fermented C. versicolor extract should provide with useful antioxidant agent in the human skin.     

In vitro hepatic biotransformation of aldrin and dieldrin in food-producing animals.

The hepatic biotransformation of aldrin (AD) and dieldrin (DD) was studied in liver post-mitochondrial supernatants (S-9s) from laying hens, female cattle and swine. S-9s were incubated with 0.03 nmol of AD or DD for 1 h. After 1 h, AD in the samples was almost epoxidated to DD. This formation was found with all the animal S-9s, and the highest rates occurred in pig S-9 (P < 0.01), followed by cow and hen S-9s. No reduction of DD was found with any of the S-9s.     

行喷式喷灌机喷灌强度和均匀度的计算

本文根据国外机组引进课题以及几次喷灌机设计计算的总结与研究,说明并推求出时针式喷灌机和平移式喷灌机喷灌强度和均匀度的计算公式,且提出了喷头水量分布的模拟计算方法。文章主要解决了行喷式喷灌机的喷灌强度和均匀度的计算问题。