干旱胁迫对盆栽“川丹参1号”生理指标及主要活性成分含量的影响

采用聚乙二醇（PEG-6000）对盆栽“川丹参1号”（CDS-1）模拟长期干旱胁迫,研究干旱胁迫对其生长情况、生理指标及主要活性成分积累的影响。结果表明,干旱胁迫显著降低CDS-1叶片中叶绿素含量,可溶性蛋白、可溶性糖和脯氨酸含量随干旱程度增加呈上升趋势,干旱胁迫下丙二醛含量显著增加,抗氧化酶（SOD、POD和CAT）活性随干旱胁迫程度增加而增加。活性成分分析表明,干旱胁迫后CDS-1根中酚酸和丹参酮类含量均有所上升,迷迭香酸和丹酚酸A含量在PEG-6000浓度为150g/L时最高,分别为CK的145%和175%,丹参酮类含量在PEG-6000浓度为50g/L时最高,增幅超60%。CDS-1在干旱胁迫下表现出适应性变化,轻度和中度干旱胁迫（PEG-6000浓度为50~100g/L）有利于CDS-1中酚酸和丹参酮类活性成分的积累,在实际生产中可通过科学控水保证和提高丹参药材的品质。     

攀杂丝瓜1号新品种选育

攀杂丝瓜1号是以从重庆九龙坡丝瓜中选育的S8-6自交系为母本,以选自上海香丝瓜的自交系S4-3为父本,培育的早熟、丰产杂一代新品种,该品种植株生长势、分枝性强,坐果率高,果实长圆柱形,匀称,皮色深绿,表皮皱,瓜纵径26.5cm,横径5.5cm,单瓜质量285.8g,商品性好,味清甜,品质优,667m2产量2918.5kg。     

An assay for quantitative virulence in Rhynchosporium commune reveals an association between effector genotype and virulence

Detailed knowledge of the evolutionary genetics of virulence is needed to understand and predict host–pathogen dynamics. This study used a virulence assay based on digital image analysis and treated virulence as a quantitative rather than a binary trait. Such quantitative data may better reflect the genetic underpinning of virulence in many pathogen systems and provide better resolution in statistical investigations. A greenhouse experiment based on a common garden design was conducted to measure virulence (% of leaf area covered by lesions) of 126 genetically distinct isolates of the barley scald pathogen, Rhynchosporium commune, originating from nine field populations around the world. Virulence in this pathosystem was found to be a quantitative trait with a continuous distribution in all populations. By comparing population genetic differentiation for virulence and neutral microsatellite markers (i.e. a Q_ST/G_ST comparison), evidence that virulence is under stabilizing selection across populations was found. Heritability values were high and ranged from 0·52 to 0·96 with a mean heritability of 0·84. Virulence was positively correlated with spore production as predicted by the trade‐off theory of virulence evolution. Furthermore, an association analysis between virulence and sequence haplotypes of three known necrosis‐inducing effector genes (NIP1, NIP2 and NIP3) revealed a significant effect of NIP2 haplotypes and NIP1 deletions. Overall, the results support a quantitative model for virulence in the R. commune–barley pathosystem and very high evolutionary potential for this trait.     

RP-HPLC法测定哈萨克药鹿根中β-蜕皮甾酮的含量

【目的】建立鹿根药材中β-蜕皮甾酮含量测定方法。【方法】采用反相高效液相色谱法,色谱柱为Waters XTerra RP C_(18)(250×4.6 mm,5μm);流动相为甲醇-1%冰醋酸溶液;体积流量为1.0 mL/min;检测波长为250 nm;柱温30℃。【结果】在上述条件下,β-蜕皮甾酮在1.45～14.5μg/mL呈良好的线性关系,加样回收率为100.39%,RSD为1.63%。【结论】该方法准确、灵敏度高、重现性好,能有效测定鹿根药材中β-蜕皮甾酮含量,可为鹿根药材的质量标准研究提供科学依据。     

Evidence of diadromy in the French Polynesian Kuhlia malo (Teleostei: Percoidei) inferred from otolith microchemistry analysis

Abstract – Strontium/Calcium (Sr/Ca) and Barium/Calcium (Ba/Ca) ratios were measured in 60 otoliths of the French Polynesian flagtail Kuhlia malo. Both elemental ratios were needed to correctly distinguish residence in marine, brackish and fresh water. High Sr/Ca and low Ba/Ca around the nucleus of all otoliths provided evidence of marine residency during the early life of all individuals. At about 0.5 mm from the core, Ba/Ca increased rapidly and remained high in all otoliths. High and unstable Sr/Ca ratios were attributed to estuarine residency, whereas low and stable Sr/Ca ratios were attributed to freshwater residency. These chemical signatures inferred that following recruitment to rivers, some fish remained in the estuary, while others moved upstream. Some individuals shared their time between fresh and brackish waters later in life. The findings of this study have important implications for the protection of nearshore, brackish and freshwater environments for the conservation of this French Polynesian diadromous species.     

皇后黑李优良单株——隆丰1号黑李的选育

对皇后黑李、隆丰1号黑李的生物学特征和植物学特性进行观察记载;开展皇后黑李优良单株的选育,选出优良单株——隆丰1号黑李。     

Interleukin-1β inhibits AKT to down-regulate eNOS Ser1177 phosphorylation in human umbilical vein endothelial cells

AIM To investigate whether interleukin-1β （IL-1β） regulates endothelial nitric oxide synthase （eNOS） phosphorylation at Ser1177 site in human umbilical vein endothelial cells （HUVECs）, and to explore its possible mechanism. METHODS The HUVECs were randomly divided into normal control group, tumor necrosis factor-α （TNF-α） group, IL-1β group, IL-6 group, SC79 ［protein kinase B （PKB/AKT） specific agonist］ group and SC79+IL-1β group. Western blot was used to determine the protein levels of eNOS, p-eNOS-Ser1177, AKT and p-AKT-Ser473 in the HUVECs. Chemical colorimetry was used to detect the nitric oxide （NO） content in the culture medium of HUVECs. RESULTS No statistically significant difference of p-eNOS-Ser1177 level in HUVECs treated with TNF-α and IL-6 was observed as compared with normal control group （P>0.05）, while the protein level of p-eNOS-Ser1177 in the HUVECs and the content of NO in the culture medium of HUVECs decreased significantly in IL-1β group （P<0.05）, and the protein level of p-AKT-Ser473 in the HUVECs was decreased as compared with normal control group （P<0.05）. The AKT agonist SC79 blocked the down-regulation effect of IL-1β on p-eNOS-Ser1177 level in the HUVECs and NO content in the culture medium of HUVECs （P<0.05）. CONCLUSION IL-1β down-regulates the protein level of p-eNOS-Ser1177 in HUVECs and affects the activity of eNOS, which may be involved in AKT/eNOS signaling pathway.     

Comparison of dietary essential amino acid requirements determined from group‐housed versus individually‐housed juvenile bluegill,Lepomis macrochirus

Two 60‐day experiments were conducted sequentially to determine (i) lysine requirement of juvenile bluegill, Lepomis macrochirus based on the dose–response method, (ii) requirements for other essential amino acids (EAAs) using whole‐body amino acid profile and (iii) whether differences in growth rates of group‐housed versus individually‐housed bluegills lead to different lysine requirement levels because of the presence and absence, respectively, of social hierarchies. Seven, semi‐purified, experimental diets (isonitrogenous, isocaloric) were prepared to contain graded levels of digestible lysine (10–31 g kg⁻¹). Experiment‐1 involved group‐housed bluegills (approximately 27 g, n = 10 fish/chamber, 4 chambers/diet) whereas experiment‐2 involved individually‐housed bluegills (approximately 30 g, n = 1 fish/chamber, 14 chambers/diet). Fish were fed twice daily to apparent satiation. Bluegill growth responses in both experiments generally improved (P < 0.05, anova ) with increasing dietary lysine levels from 10 to 16 g kg⁻¹, and then levelled off with further increase in lysine level (P > 0.05). Optimal dietary lysine level (digestible basis) was estimated to be 15 g kg⁻¹ based on broken‐line regression analyses of relative growth rate and feed conversion ratio with no differences being observed between the two rearing methods. Determined dietary requirement levels for other EAAs ranged from 2.4 g kg⁻¹ (tryptophan) to 15.3 g kg⁻¹ (leucine).     

High dietary energy level stimulates growth hormone receptor and feed utilization in large Atlantic salmon (Salmo salar L.) under hypoxic conditions

This study examines how appetite and growth regulation of Atlantic salmon are affected by low dissolved oxygen (LO) and dietary digestible energy levels (DE: high [HE] vs. low [LE]). Long‐term exposure to LO resulted in a reduced feed intake, growth, digestible protein and fat retention efficiencies and increased feed conversation ratio and plasma ghrelin concentrations (p < .05) compared to high dissolved oxygen (HO). Pair‐feeding of rations based on the feed intake of the LO groups, but fed at HO, resulted in a 50% growth improvement in HE diet groups. This suggests that the poor growth under LO was not entirely caused by the reduced feed intake. Salmon adapted to LO by increased haemoglobin concentrations, while osmoregulation was affected by increased plasma chloride concentrations (p < .05). Plasma ghrelin concentration was unaffected by DE (p > .05). Growth regulation was affected by the HE diet, with increased liver and muscle growth hormone receptor ghr1 mRNA (p < .05), regardless of oxygen level. The growth depression due to low oxygen appears to be related to higher metabolic costs, while higher DE upregulates the GH‐IGF system at the ghr1 level and found to be beneficial for growth, feed intake, oxyregulation and osmoregulation under hypoxia.