杭州地区田间稻纵卷叶螟对不同组分雌性外激素的趋性

 :1998～ 1999年 ,分别用日本、菲律宾和印度种群雌性外激素组分特征的性诱剂在中国浙江省杭州进行了稻纵卷叶螟 ( Cnphalocrocismedinalis)的性诱剂田间诱捕试验。研究发现 ,具有日本种群雌性激素组分特征的性诱剂对雄性稻纵卷叶螟的诱集效果好 ,其他性诱剂与之相比差异显著     

Genetic identification and morphology of naturally spawned eggs of the Japanese eel Anguilla japonica collected in the western North Pacific

Eggs of the Japanese eel Anguilla japonica collected in the western North Pacific were identified by onboard species-specific polymerase chain reaction (PCR) and DNA nucleotide sequencing after the cruise. Fish eggs of various species were collected by large plankton net tows at 12 stations along the southern part of the West Mariana Ridge on 19–25 May 2009. A total of 43 fish eggs were distinguished morphologically as possibly being of A. japonica. Thirty-one of those were analyzed by PCR, which included 15 eggs collected at 12°50–55′N, 141°15–20′E (in 5 tows) that showed positive results. The 16S ribosomal RNA (rRNA) gene sequences of eggs determined after the cruise indicated that 31 A. japonica eggs had been collected. The remaining eggs were of mesopelagic eel species (Serrivomeridae and Derichthyidae), or unidentified species. The morphological characteristics of the A. japonica eggs were consistent with those of artificially spawned eggs, except they had a slightly larger diameter. The egg diameter range did not overlap with those of mesopelagic eels of the Serrivomeridae, which often spawn in the same area as A. japonica. These results suggest that egg diameter and embryo shape can be used to morphologically identify naturally spawned A. japonica eggs.     

Effect of juglone on the survival time of two Brachionus species (Rotifera): species-specific tolerance against oxidative stress

To investigate the effect of oxidative stress on the survival of two Brachionus species of rotifer, we examined the effective dose of juglone, which generates reactive oxygen species, and compared survival times between the two species. First, we observed that juglone affected survival in the rotifers in a dose-dependent manner between 0.02 to 20 μM, and that treatment at above 2 μM showed acute toxicity causing the animals to die within a few hours. Next, we found the difference in survival time between the two species exposed to 20 μM juglone: B. rotundiformis was significantly more tolerant against the substance than the allied species B. plicatilis. The findings suggest that exploring the basis of species-specific abilities to persist under oxidative stress will be of great interest to uncover the underlying mechanisms governing the stress resistance of the rotifer, as well as contributing to their stable mass production for aquaculture.     

Native and introduced Far Eastern daces,genus Tribolodon,in the Tama River system,Japan, inferred from mitochondrial DNA analysis

Fisheries Science - To investigate the species composition and genetic characteristics of Far Eastern daces, genus Tribolodon, in the Tama River, Japan, partial DNA sequences of the mitochondrial...     

Combined treatment of aminoethoxyvinylglycine (AVG) and 1-methylcyclopropene (1-MCP) reduces melting-flesh peach fruit softening

The effects of postharvest application of aminoethoxyvinylglycine (AVG) and 1-methylcyclopropene (1-MCP) on ethylene production and fruit quality, and thus on transportation and shelf-life, were evaluated in melting-flesh peaches. AVG (150 mg L⁻¹) significantly reduced ethylene production, and the effect was enhanced in combination with 1-MCP (1 μL L⁻¹). However, fruit treated with AVG alone softened to untreated control levels 2 d after harvest (DAH). Treatment with 1-MCP significantly reduced the rate of softening until 2 DAH, but the fruit rapidly softened thereafter, and reached untreated control levels by 4 DAH. A combination of AVG and 1-MCP significantly reduced fruit tissue softening throughout ripening. The effect of each chemical on flesh firmness indicated that 1-MCP affected fruit response in the early stages of ripening up to 4 DAH, and AVG significantly reduced softening in the latter stages from 4 to 9 DAH. Peaches treated with AVG and 1-MCP retained their ground color during ripening, but the effect of each chemical on color is unclear. The present study indicates that combined treatment with AVG and 1-MCP significantly delays the ripening of melting-flesh peaches.     

Biological nitrate removal using sugar-industry wastes

Biological denitrification experiment was conducted using sugar-industry wastes, namely final molasses as a carbon source and bagasse charcoal pellets as supporting media for denitrifying bacteria. We employed an upflow fixed-bed reactor filled with the pellets and biofilm attached onto them. This was fed with potassium-nitrate and dilute-molasses solutions. Total nitrogen removals of more than 85% were achieved at influent carbon–nitrogen (C/N) ratios between 2 and 4, and hydraulic residence times of more than 0.8 h. This demonstrated that final molasses could be used as an alternative carbon source. On the other hand, final molasses also contained some organic/ammonium nitrogen and refractory organic matter including colors, both of which were difficult to remove with the reactor. Accordingly, at higher C/N ratios, these substances caused major increases in effluent total-nitrogen and organic-carbon concentrations. Therefore, an optimum C/N ratio was found to be around 2.     

1NM-PP1 treatment of mice infected with Toxoplasma gondii

Bumped kinase inhibitors (BKIs) target analog-sensitive kinases, which the genomes of mammals rarely encode. Previously, we demonstrated that a BKI effectively suppressed the in vitro replication of Toxoplasma gondii, the causative pathogen of toxoplasmosis, by targeting T. gondii calcium-dependent protein kinase 1 (TgCDPK1) (Eukaryotic Cell, 9: 667-670). Here, we examined whether the BKI 1NM-PP1 reduced parasite replication in vivo. A high dose of 1NM-PP1, by intraperitoneal injection, just before the parasite inoculation effectively reduced the parasite load in the brains, livers, and lungs of T. gondii-infected mice, however, a low dose of 1NM-PP1 with oral administration didn't change the survival rates of infected mice.     

Combined use of a synthetic trail pheromone and insecticidal bait provides effective control of an invasive ant

BACKGROUND: Except for sex pheromones, use of pheromones in pest management has been largely unexplored. A high concentration of trail pheromone disrupts ant trail following and foraging, and thus synthetic trail pheromone can be a novel control agent for pest ants. In this study, a year‐long treatment of small areas (100 m² plots of urban house gardens) with synthetic trail pheromone, insecticidal bait or both was conducted to develop a novel control method of the invasive Argentine ant Linepithema humile (Mayr). RESULTS: The ant population could be maintained lower than or similar to the initial level only by combined treatment with synthetic trail pheromone and insecticidal bait. Actually, the ant population was nearly always lowest in combination treatment plots. Throughout the study period, the ant population in plots treated with either one of synthetic trail pheromone or insecticidal bait remained similar to no‐treatment plots. CONCLUSIONS: Combination treatment may be a more effective and environmentally friendly method for controlling invasive ants than conventional methods. Extermination of ants by insecticidal bait and inhibition of re‐infestation by pheromone may be the mechanism of the combination effect. This is the first study to show a significant effect of synthetic trail pheromone on ant population. Copyright © 2011 Society of Chemical Industry     

Molecular cytogenetic study in Octopus (Amphioctopus) areolatus from Japan

Octopus (Amphioctopus) areolatus is an important marine cephalopod in Japan. We examined its diploid chromosome number, karyotype, and genome size (C value), and performed fluorescence in situ hybridization (FISH) using a vertebrate telomeric probe. The diploid chromosome number was 60 in embryonic cells, with 24 pairs of metacentric chromosomes, four pairs of metacentric/submetacentric chromosomes, and two pairs of submetacentric chromosomes. The mean C value was estimated to be 5.47 pg. From these findings, and those reported previously for other octopus species, we suggest that the factor causing the quantum change of C value in O. (A.) areolatus was genome duplication, and not polyploidy. In telomeric FISH analysis, hybridization signals were clearly observed in the telomeric regions of the chromosomes. This is the first report of FISH analysis of cephalopod chromosomes, and our findings suggest that the telomere sequence of O. (A.) areolatus is (TTAGGG) _n , which may allow gene mapping in the future.