Antagonism of pheromone response of Ostrinia nubilalis males and implications on behavior in the laboratory and in the field     

Riba M  Sans A  Solé J  Muñoz L  Bosch MP  Rosell G  Guerrero A 《Journal of agricultural and food chemistry》2005,53(4):1158-1165

The antagonistic effect on the pheromone response and catabolism of male European corn borers, Ostrinia nubilalis, by several trifluoromethyl ketones is reported. (Z)-11-Tetradecenyl trifluoromethyl ketone (Z11-14:TFMK), the most closely related analogue of the main component of the pheromone, elicits a remarkable disruptive effect on close approach and source contact of males flying to a source baited with mixtures of the pheromone and the antagonist in 5:1 and 10:1 ratios. In this experiment, the male displayed an erratic flight track with frequent counter turns and intersections with the plume. In the field, the TFMK significantly lowered the number of males caught when mixed with the pheromone in a 10:1 ratio in comparison with the natural attractant. The compound was also a good inhibitor of the antennal esterase of the insect with a IC(50) value of 0.28 muM. The homologous (Z)-10-tridecenyl trifluoromethyl ketone, with one carbon less in the chain, also elicited an antagonistic effect in the wind tunnel, but in the field, the results were not conclusive. The effect induced was lower than the one displayed by Z11-14:TFMK including the activity as the esterase inhibitor (IC(50) value of 7.55 muM). The saturated tetradecyl trifluoromethyl ketone, tetradecyltrifluoropyruvamide, and (Z)-11-2-thiatetradecenyl trifluoromethyl ketone resulted completely inactive. The results obtained in conjunction to the previously shown low toxicity to mice by related trifluoromethyl ketones provide new important data for the putative utilization of these chemicals as new pest control agents.  相似文献   

Evaluation of the cytotoxicity, genotoxicity, mutagenicity, and antimutagenicity of propolis from Tucuman, Argentina     

Nieva Moreno MI  Zampini IC  Ordóñez RM  Jaime GS  Vattuone MA  Isla MI 《Journal of agricultural and food chemistry》2005,53(23):8957-8962

This study evaluates the toxic, genotoxic/mutagenic, and antimutagenic effects of propolis extract from Amaicha del Valle, Tucumán, Argentina. The cytotoxicity assays carried out with the lethality test of Artemia salina revealed that the LD50 was around 100 microg/mL. Propolis extracts showed no toxicity to Salmonella typhimurium TA98 and TA100 strains and Allium cepa at concentrations that have antibiotic and antioxidant activities. Otherwise, for the testing doses, neither genotoxicity nor mutagenicity was found in any sample. The propolis extracts were able to inhibit the mutagenesis of isoquinoline (IQ) and 4-nitro o-phenylenediamine (NPD) with ID50 values of 40 and 20 microg/plate, respectively. From this result, the studied propolis may be inferred to contain some chemical compounds capable of inhibiting the mutagenicity of direct-acting and indirect-acting mutagens. A compound isolated from Amaicha del Valle propolis, 2',4'-dihydroxychalcone, showed cytotoxic activity (LC50 values of 0.5 microg/mL) but was not genotoxic or mutagenic. Furthermore, this compound was able to inhibit the mutagenicity of IQ (ID50 values of 1 microg/plate) but was unable to inhibit the mutagenicity of NPD. Our results suggest a potential anticarcinogenic activity of Amaicha del Valle propolis and the chalcone isolated from it.  相似文献   

Modeling the timber supply impact of introducing weevil-resistant spruce in British Columbia with cellular automata     

Olaf Schwab  Thomas Maness  Gary Bull  Clive Welham  Brad Seely  Juan Blanco 《Forest Policy and Economics》2011,13(1):61-68

Assessing the impacts of cumulative, non-lethal damages to forests poses a particular challenge to forest management planning since cumulative merchantable volume losses are not known until the time of harvest. This paper introduces a model that scales stand-level processes to their large-scale implications by combining elements of growth and yield modeling, insect infestation modeling, and large-scale spatial harvest simulation. The model is described and tested using the proposed large-scale introduction of weevil-resistant spruce in British Columbia, Canada as a case study. While spruce weevil damages were found to be significant, only a relatively small percentage of losses can be avoided by planting resistant stock. The model introduced in this paper can serve as an important decision support tool for policy makers and researchers in assessing the large-scale effects of proposed policy and management interventions.  相似文献   

Lactate Dehydrogenases in Human Testes     

Blanco A  Zinkham WH 《Science (New York, N.Y.)》1963,139(3555):601-602

A unique form of lactate dehydrogenase was observed in the starch-gel electrophoretic patterns of adult human testes. It was present in sperm, but absent in prepubertal testes. Its electrophoretic mobility, heat stability, kinetic behavior with pyridine nucleotide analogs, and chromatographic characteristics on diethylaminoethyl cellulose were intermediate to those observed for lactate dehydrogenase isozymes 3 and 4.  相似文献   

Agronomic performance and combining ability estimates of yellow maize inbred lines under adequate and deficit moisture conditions     

Amegbor  Isaac Kodzo  Abe  Ayodeji  Adjebeng-Danquah  Joseph  Adu  Gloria Baokyewaa  Oteng-Frimpong  Richard 《Journal of Crop Science and Biotechnology》2022,25(2):183-197

Journal of Crop Science and Biotechnology - Breeding for drought tolerance and increased grain yield is vital in mitigating the threat posed by recurrent drought stress on maize production, as well...  相似文献   

What about the children? The experience of families involved in an adult-focused diabetes intervention     

Laroche HH  Davis MM  Forman J  Palmisano G  Heisler M 《Public health nutrition》2008,11(4):427-436

OBJECTIVE: Among adults with diabetes attempting to change their own diets, we explored how these adults approached providing food for their children and how their children reacted to dietary changes in the household. DESIGN: The research design used semi-structured parallel individual interviews of adults and a child (aged 10-17 years) in their home. Interviews were audio-taped, transcribed, coded and analysed for themes. SUBJECTS: Subjects included families in which one inner-city African American or Latino adult with diabetes had completed a diabetes intervention promoting healthy dietary behaviours. RESULTS: We completed 29 interviews (14 adult-child pairs and one child). Adults approached making dietary changes for themselves and also providing food for their family in different ways, ranging from expecting everyone to eat the same thing to preparing two separate meals. Many children resisted dietary changes while fewer acquiesced. Among children who went along with changes, some reported resisting initially then adjusting, while others did not resist because the food still tasted good or they could obtain preferred foods outside the house. The intersection of adults' meal strategies and children's reactions to the changes can be used to categorise families into different patterns. These patterns highlight the tension between an adult who must make dietary changes to control diabetes and a child who is not necessarily motivated to change. CONCLUSION: From this framework we suggest hypotheses about how these patterns might influence dietary behaviour in adults and children. Understanding these patterns could guide interventions to assist parents in successfully including children in their dietary changes.  相似文献   

Investigation of the mechanism of enhanced effect of EGCG on huperzine A's inhibition of acetylcholinesterase activity in rats by a multispectroscopic method     

Xiao J  Chen X  Zhang L  Talbot SG  Li GC  Xu M 《Journal of agricultural and food chemistry》2008,56(3):910-915

The mechanism of enhanced effect of (-)-epigallocatechin-3-gallate (EGCG) on huperzine A's (HUP) inhibition of acetylcholinesterase (AChE) activity in rats was investigated. The inhibitory effects of HUP at 10 and 5 microg/kg on AChE activity were quite weak in the whole phase. In contrast, upon addition of EGCG (100 mg/kg) to the HUP 10 and 5 microg/kg groups, remarkably enhanced inhibitory effects with maximum inhibitory percentages of 90.94 and 88.13% were observed under the same conditions. EGCG also can greatly prolong the inhibitory time. The mechanism of the enhanced effects of EGCG on HUP's inhibition of AChE activity was investigated by steady fluorescence spectroscopy, infrared spectroscopy, and ultraviolet spectroscopy. HUP hardly interacted with the main transport protein, whereas there was a very strong binding interaction between EGCG and bovine serum albumin. The enhanced transport of HUP is a possible cause of the enhanced effect of EGCG on HUP bioactivity.  相似文献   

Early assessment of gilthead sea bream (Sparus aurata) spawning dynamics by mini‐broodstocks          下载免费PDF全文

Carmen García‐Fernández  José A Sánchez  Gloria Blanco 《Aquaculture Research》2018,49(1):36-47

The implementation of any sustainable breeding program requires a maximization of effective size (Ne) to maintain inbreeding rate at minimum levels. However, the control of Ne remains a major challenge for those species whose reproduction in captivity is based on a spawning strategy where there is no control over the established matings. The present study aims to assess the spawning dynamic of gilthead sea bream (Sparus aurata) at different dates from two mini‐broodstocks (4 ♀ and 4 ♂). Here we report the use of a simple protocol based on the genotyping of fertilized eggs from a reduced set of microsatellite loci which provides a quick evaluation of daily spawning in terms of family structuring (number of active breeders and number and family size). According to our results, the daily spawning dynamics is characterized by a fluctuation in the number of active breeders, reaching maximum values (until 100%) during peak production phase. However, the proportion of possible mating (families) in a single daily spawning never exceeded more than 81%. Unbalanced parental contributions were highly frequent, with extreme cases involving the assignment of 50%–90% of the offspring to a single family. Therefore, the use of mini‐broodstocks and the grouping of spawning harvested at different dates are proposed as strategies to minimize the inbreeding risk by providing a more optimal pattern of family structuring (increase in the number of families obtained and a more balanced parental contributions) that entails a more conservative Ne/N ratio.  相似文献   

An environmentally sustainable approach for the management of <Emphasis Type="Italic">Phaeoacremonium minimum</Emphasis>, the main agent of wood diseases in <Emphasis Type="Italic">Actinidia deliciosa</Emphasis>     

Roberta Roberti  Fabio Osti  Gloria Innocenti  Adamo Domenico Rombolà  Stefano Di Marco 《European journal of plant pathology / European Foundation for Plant Pathology》2017,148(1):151-162

Among the fungi associated with the kiwi wood diseases, the vascular pathogen Phaeoacremonium minimum can infect plants already at nursery stage, without any external symptoms. At the moment, there are not effective control strategies. The effect of soil treatments applicable in organic agriculture was evaluated in two-years experiments on potted kiwi plants artificially inoculated with P. minimum. The soil treatments were based on commercial formulations of iron chelate, silicon, neem paste, Trichoderma afroharzianum strain T22, and cover cropping with selected perennial Poaceae. Cover cropping and iron chelate treatments enhanced the iron availability for the plants and significantly reduced wood necrosis caused by the pathogen. Both treatments also produced an increase of hairy root proliferation, so the plants were able to better cope with stress conditions. Laboratory assays showed the role of iron on the pathogen growth and its pathogenesis enzyme activities.  相似文献