春尺蠖成虫羽化发蛾特性及应用佳多频振式杀虫灯控害效应研究初报

春尺蠖羽化发蛾特性研究表明，发蛾期与气温密切相关。邻近城区比郊外大田发蛾期早7～10d；发蛾前期雄蛾多于雌蛾，以后雌蛾增多；成虫为全日程羽化出土，雌雄性比为1：1．42；雌蛾交尾最多可达3次，雄蛾仅1次。应用佳多频振式杀虫灯诱捕春尺蠖雄蛾数量大。灯距120m范围内，树干表皮单位面积上的有效卵率较无灯对照区下降了24％～61．5％，控害效果显著。     

Study of programmed cell death in bovine herpesvirus 1 infected MDBK cells and the possible role of nitric oxide in this process

Bovine herpesvirus 1 (BHV-1) is the aetiological agent of many disease types and may predispose infected animals, possibly through immunosuppression, to secondary bacterial infections. Immunosuppression may directly be associated with the induction of programmed cell death (PCD) in some virus-infected cells. Nitric oxide (NO) has an important mediating role against fungal, bacterial, protozoal, viral pathogens and tumours. BHV-1 induced apoptosis between 0.5-3 h postinfection (PI) in MDBK cells; however, between 3 and 6 h PI the PCD response was found to be decreased. It was interesting to see that BHV-I inhibited staurosporin-induced PCD after 1 h. These results showed similarities with those obtained from herpes simplex type I infections in human epithelial cells. PCD response decreased 1 h following caspase-3 inhibitor applications, whereas NO response increased 3 h following infection in the presence of caspase-8 and -9 inhibitory peptides. In conclusion, BHV-1 inhibited the staurosporin-induced apoptotic response and also the NO response. We propose that this inhibition is caspase-3 dependent.     

Effect of maternal seaweed extract supplementation on suckling piglet growth, humoral immunity, selected microflora, and immune response after an ex vivo lipopolysaccharide challenge

The present study was conducted to investigate the effect of maternal dietary supplementation (n = 10 sows/treatment) with seaweed extract (SWE: 0 vs. 10.0 g/d) from d 107 of gestation until weaning (d 26) on neonatal piglet growth, humoral immunity, intestinal morphology, selected intestinal microflora, and VFA concentrations. Furthermore, this study examined the effect of dietary treatment on the immune response after an ex vivo Escherichia coli lipopolysaccharide (LPS) tissue challenge at weaning in a 2 × 2 factorial arrangement. The main factors consisted of sow dietary treatment (SWE or control) and immunological challenge (yes or no). The SWE supplement (10.0 g/d) contained laminarin (1.0 g), fucoidan (0.8 g), and ash (8.2 g) and was extracted from a Laminaria spp. The SWE-supplemented sows had greater colostrum IgA (P < 0.01) and had a trend for greater IgG (P = 0.062) concentrations compared with non-SWE-supplemented sows. Piglets suckling SWE-supplemented sows had greater serum IgG (P < 0.05) concentrations on d 14 of lactation compared with those suckling non-SWE-supplemented sows. Dietary SWE supplementation decreased fecal Enterobacteriaceae populations in sows at parturition (P < 0.05), and piglets suckling SWE-supplemented sows had a decreased colonic E. coli population at weaning (P < 0.01) compared with non-SWE-supplemented sows. Lipopolysaccharide challenge increased the mRNA abundances of the pro-inflammatory cytokines IL-1α and IL-6 (P < 0.01) in ileal tissue and tumor necrosis factor (TNF)-α in colonic (P < 0.01) tissue. There was a treatment × LPS challenge interaction for ileal TNF-α mRNA expression (P < 0.05). Piglets suckling SWE-supplemented sows had greater TNF-α mRNA expression after ex vivo LPS challenge compared with non-SWE-supplemented sows (P < 0.05). However, there was no effect of sow dietary treatment on TNF-α mRNA expression in the unchallenged ileal tissue. Piglet BW at birth and weaning, and small intestinal morphology were unaffected by sow dietary treatment under current experimental conditions. In summary, these results demonstrate an important immunomodulatory role of SWE supplementation characterized by enhanced colostral IgA and IgG concentrations, greater piglet circulatory IgG concentrations on d 14 of lactation, and enhanced TNF-α mRNA expression in the ileum after an ex vivo LPS challenge. These results indicate that SWE supplementation enhanced piglet immune function and colonic microflora at weaning.     

Determining the Internal Connection Ratios by MRI and Their Effects on Grafted Rooted Vine Growing Features of cvs. Merlot and Syrah

This experiment was carried out to determine the percentage of internal connection between rootstock and scion in graft union with nondestructive and noninvasive MRI (Magnetic Resonance Imaging) method and to follow performance status according to internal connection ratios of the grafted rooted vines after planting to vineyard field. Research was established in a factorial randomized block design and carried out with cvs. Merlot and Syrah grafted onto 110?R rootstock and 4 different internal (MRI) connection levels in 3 replications. The percentages of grafted rooted vine internal determination by MRI by four sides (13.75%) in graft union were found to be very low than others at the pre-planting stage. An increase in the internal connection ratio in the majority of the grafted rooted vines was determined after the vegetative growth phase. Therefore, the internal connection ratios of the graft union of rooted vines of cvs. Merlot and Syrah varieties showed a tendency to increase during the second year of development. Again in both cultivars, loss rate of grafted rooted vines showed a decreasing tendency depending on increase of internal connection ratio of graft union. As a result, in case of decrease of MRI costs, it is thought that grafted rooted vine producers may have the opportunity to supply better quality seedlings to vine growers using MRI techniques.     

Chemical control of maize late wilt in the field

Late wilt, a severe vascular disease of maize caused by the fungus Harpophora maydis, is characterized by relatively rapid wilting of maize plants before tasseling and until shortly before maturity. In Israel, the disease has become a major problem in recent years. The pathogen is currently controlled using cultivars of maize having reduced sensitivity. In an earlier work, we modified a molecular method for use as a diagnostic tool to evaluate disease progression in field-infested plants and showed that several fungicides suppressed H. maydis in vitro. Here, we examine the effect of different fungicides on disease progression in a contaminated maize field in the spring and summer of 2009 and 2010. The field was watered using a drip irrigation line for each row and the fungicides were injected directly into the drip line. One of the four fungicides tested, azoxystrobin, was highly effective compared with the control, inhibited the development of wilt symptoms and recovered cob yield by 100%. Although this is the first success in preventing disease symptoms in infested fields in Israel, the azoxystrobin treatment did not reduce the amounts of pathogen DNA in host tissues or delay its spread. Attempts to reduce concentrations of this fungicide or to apply it by spraying were less effective than the triple full dosage treatment. The presence of the pathogen in the host tissues of the successfully treated plants and its ability to undergo pathogenic variations are increasing the risk of pathogen resistance and the urgent need to develop new ways of controlling late wilt.     

Antioxidant Activities of Citrus Albedo and Flavedo Fragments Against Fish Lipid Oxidation

ABSTRACT

This research aimed to inhibit the oxidation of fish lipid by adding the ethanol extracts of albedo and flavedo fragments of grapefruit, sour orange, and bergamot. The samples were stored at 25°C, and analyses were performed on weekly intervals. The albedo fragments of sour orange extract had the highest antioxidant activity (0.342 ± 0.002 µM Trolox) and total phenolic content (5.29 ± 0.00 g GAE/100 g dry matter). Lipid oxidation increased rapidly in control samples compared to the extract treatments. The lowest scores for thiobarbituric acid reactive substances (TBARS), para-anisidine value, peroxide value, and UV absorbance values were determined in sour orange albedo extracts as 5.21 mg MDA/kg, 17.81 and 4.78 meq O₂/kg, 2.24, and 0.403, respectively, at the end of the storage. More successful results were obtained with the peels of grapefruit and bergamot in supressing the lipid oxidation. Bergamot extract was the most preferred citrus in terms of sensory analyses.     

Molecular identification of a phytoplasma associated with Russian olive witches’ broom in Iran

Russian olive trees (Elaeagnus angustifolia) showing witches’ broom symptoms typical of phytoplasma infection were observed in the Urmia region of Iran. A phytoplasma named Russian olive witches’ broom phytoplasma (ROWBp-U) was detected from all symptomatic samples by amplification of the 16S rRNA gene and 16S/23S rDNA spacer region using the polymerase chain reaction (PCR) which gave a product of expected length. DNA from symptomless plants used as a negative control yielded no product. The sequence of the 16S rRNA gene and 16S/23S rDNA spacer region of ROWBp-U showed 99% similarity with the homologous genes of members of the aster yellows group. We also detected a phytoplasma in neighboring alfalfa plants (AlWBp-U) showing severe witches’ broom symptoms. An 1107 bp PCR product from the 16S rRNA gene showed 99% homology with the corresponding product in ROWBp-U, suggesting the presence of the same phytoplasma actively vectored in the area. Further observations showed that Russian olive trees with typical ROWB symptoms were present in an orchard near Tehran which is located over 530 km south-east of the original Urmia site. The corresponding sequence of this phytoplasma (ROWBp-T) showed 99% homology to that of the ROWBp-U. A sequence homology study based on the 16S rRNA gene and 16S/23S rDNA spacer region of ROWBp-U and other phytoplasmas showed that ROWBp-U is most closely related to the 16SrI group. To our knowledge, this is the first report of a phytoplasma infection in a member of the Elaeagnaceae.