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141.
Aequipecten opercularis (Queen scallop) and Mimachlamys (Chlamys) varia (Black scallop) are important natural resources occurring in Atlantic and Mediterranean coasts. To develop an optimal sustainable exploitation plan, it is important to study the genetic structure of the different populations. In this study, we used polymerase chain reaction‐restriction fragment length polymorphisms for the determination of the genetic variation and population structure of these two species in different localities. Ten composite haplotypes were generated for A. opercularis and 15 haplotypes for M. varia. Of these, six and four were unique respectively. The analysis of the distribution of the different haplotypes between the localities showed no clear evidence of subdivision in A. opercularis, while in M. varia the results indicated that the two localities analysed should be managed as separate stocks.  相似文献   
142.
Amaranth is taking great attention as an important cereal crop that could fulfill food requirements for the growing population, especially in developing countries. However, the protein composition of these seeds is not well known yet. We have used the proteomics tools to characterize amaranth seed proteome. About 400 proteins spots were resolved on two-dimensional gel electrophoresis (2-DE) and protein spots were analyzed by LC-MS/MS (liquid chromatography tandem mass spectrometry). Identified proteins were related to stress and defense responses, metabolic, respiratory, and oxide-reduction processes. One abundant spot was identified as a Late Embryogenesis Abundant (LEA) protein and the gene was cloned and characterized. The AcLEA cDNA contains a 418 bp open reading frame (ORF) encoding a polypeptide of 139 amino acids. Bioinformatics analysis showed that AcLEA belongs to LEAs Group 5. Proteomics is a powerful technique that could be used even in non-sequenced organisms such as amaranth. The obtained information reveals that amaranth seed, beyond the classical seed storage proteins, contains proteins related to protection against stress. The identification of these proteins opens the door to the application of new strategies to improve the quality of amaranth production.  相似文献   
143.
Several ethyl 2,3-dihydro-3-oxoisothiazolo[5,4-b]pyridine-2-alkanoate derivatives were synthesized as herbicides. Only 5-methyl derivatives inhibited both hypocotyl and root growth in the lettuce (Lactuca sativa L.) seedling test at 100 mg litre-1. Only ethyl propionate and valerate derivatives showed significant inhibition at 0·1 mg litre-1, whereas ethyl acetate or butyrate derivatives were inactive. Contrary to unoxidized derivatives, the inhibitory effect of 1-oxide and 1,1-dioxide derivatives was strongly dependent on concentration; ethyl 2,3-dihydro-5-methyl-3-oxoisothiazolo[5,4-b]pyridine-2-propionate 1,1-dioxide inhibited 100% of germination at 100 mg litre-1 and 45% of lettuce seedling growth at 0·1 mg litre-1. Quantitative structure–inhibition of growth relationship analysis carried out by adaptive least-squares (ALS) method gave a good correlation with small and hydrophobic 5-substituents as well as with odd carbon-chain ethyl alkanoates in position 2. Active compounds did not show auxin-like activity from 0·1 to 100 mg litre-1. © 1997 SCI.  相似文献   
144.
In this study, clinical, parasitological and histopathological findings of thirteen kelp gulls (Larus dominicanus) found infected with eyeflukes in Brazil are presented. Parasites detected in the ventral conjunctival fornix were identified as Philophthalmus lachrymosus [mean intensity of infection: 16 (5–36) worms/bird]. Eleven birds (85%) presented signs of systemic disease, such as emaciation, dehydration and depressed consciousness. Conjunctival hyperemia was observed in 22 eyes (85%). Keratitis, corneal ulcers, corneal abscess and chemosis were also detected in some eyes (4–8%). Histopathologic lesions, likely due to the parasite attachment to the conjunctiva, were found in the eyes of one infected bird that died from unrelated causes. Philophthalmosis by P. lachrymosus is here reported as a clinically relevant eye disease in kelp gulls.  相似文献   
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146.
Since its detection in the Mediterranean basin at the end of 2006 and later in other European countries, the South American tomato pinworm, Tuta absoluta (Meyrick), has become a serious threat to tomato crops. In newly infested areas, it is especially problematic during the first years of its presence. Nevertheless, after 2–3 years, the incidence of T. absoluta has become less severe in certain areas. There are several factors contributing to this decline, such as the increase in growers' knowledge of pest behaviour and biology and the correct application of integrated pest control strategies. The impact of opportunistic native natural enemies (fortuitous biological control) should be considered as one of the key factors in this decline. In this review, available information on indigenous natural enemies is updated, and the current pest management approaches used against T. absoluta are addressed. Finally, future scenarios for biological control of this pest are discussed. Copyright © 2012 Society of Chemical Industry  相似文献   
147.
Numerous plants ofSilene nicaeensis having symptoms resembling those associated with the presence of phytoplasmas were observed in an extensive coastal area in the south of Italy. Microscopic observation showed histological abnormalities in the organization of tissues in symptomatic plants, and molecular tests, including PCR/RFLP analyses and nucleic acid sequencing, revealed the presence of phytoplasmas belonging to the aster yellows group (‘Candidatus phytoplasma asteris’). This is the first report of phytoplasma infection inS. nicaeensis, a wild species that colonizes the Calabrian coast. http://www.phytoparasitica.org posting June 12, 2008  相似文献   
148.
We evaluated the effects of macronutrient and micronutrient omission, and of liming, on Jatropha curcas (JC) in greenhouse study. The experimental design was a factorial combination of 2 liming treatments (nil or 4.5 t. ha?1 of dolomitic lime) x 7 combinations of fertility status, with five replications. The concentrations and uptake of nutrients by JC plants follow the order: nitrogen > potassium > calcium ≥ Magnesium > sulfur > phosphorus > iron > boron > manganese > zinc > copper (N > K > Ca ≥ Mg > S > P > Fe > B > Mn > Zn > Cu), but the growth of JC plants was negatively affected mainly by omission of macronutrients, in the following order: P > N = K = S, on limed soil. Phosphorus is the most critical element for development. JC is responsive to micronutrients only when applied together with macronutrients. Potassium chloride is not recommended as K+ source for JC crop. Lime is recommended to improve growth and nutritional status of JC plants.  相似文献   
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150.
A new liquid chromatography methodology coupled to a diode array detector and a time-of-flight mass spectrometer has been developed for the simultaneous determination of phenolic compounds and saponins in quinoa (Chenopodium quinoa Willd). This method has allowed the simultaneous determination of these two families of compounds with the same analytical method for the first time. A fused-core column C18 has been used, and the analysis has been performed in less than 27 min. Both chromatographic and electrospray ionization time-of-flight mass spectrometry parameters have been optimized to improve the sensitivity and to maximize the number of compounds detected. A validation of the method has also been carried out, and free and bound polar fractions of quinoa have been studied. Twenty-five compounds have been tentatively identified and quantified in the free polar fraction, while five compounds have been tentatively identified and quantified in the bound polar fraction. It is important to highlight that 1-O-galloyl-β-D-glucoside, acacetin, protocatechuic acid 4-O-glucoside, penstebioside, ethyl-m-digallate, (epi)-gallocatechin, and canthoside have been tentatively identified for the first time in quinoa. Free phenolic compounds have been found to be in the range of 2.746-3.803 g/kg of quinoa, while bound phenolic compounds were present in a concentration that varies from 0.139 and 0.164 g/kg. Indeed, saponins have been found to be in a concentration that ranged from 5.6 to 7.5% of the total composition of whole quinoa flour.  相似文献   
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