The effect of amino acids and amides on the regulation of nitrate uptake by wheat seedlings     

Claudio O. Rodgers  Atilio J. Barneix 《Journal of plant nutrition》2013,36(2):337-348

Wheat plants grown hydroponically increased their nitrate uptake rate more than two‐fold after three days of N starvation. Exogenously supplied amino acids and amides had no effect on the nitrate uptake rate of plants well nourished in N. After three days of N starvation, however, some of the amino acids and amides supplied to plants inhibited up to 50% of the nitrate uptake rate. The most effective inhibitor was aspartic acid. Asparagine, glutamine or phenylalanine did not show any inhibitory effect. The percentage of inhibition was not increased by increasing the amino acid concentration, nor did the addition of mixed amino acids and amides increase the inhibition exerted by one amino acid alone. During the three days of N starvation, there was a decrease in the concentration of endogenous amino acids in the roots, but not all amino acids decreased their concentration at the same rate.

It is suggested that the endogenous levels of some amino acids may repress the nitrate uptake system in plants well supplied with N. During the development of the N deficiency, the concentration of these amino acid decreases, de‐repressing the nitrate uptake system.  相似文献   

Abundance of White-fronted Parrots and diet of an urban parrot assemblage(Aves:Psittaciformes)in a green Neotropical city     

Cristel álvarez-Castillo  Ian MacGregor-Fors  Stefan L.Arriaga-Weiss  Claudio Mota-Vargas  Diego Santiago-Alarcon 《中国鸟类》2022,(1):36-42

Urban ecosystems are evolutionarily recent novel environments acting as biodiversity filters.Psittacidae birds are considered successful urban adapters mainly d...  相似文献   

Agriculturally intensified landscapes are associated with reduced body condition of lady beetles     

Tiede  Julia  Iuliano  Benjamin  Gratton  Claudio 《Landscape Ecology》2022,37(7):1921-1936

Landscape Ecology - Agricultural intensification is contributing to a global species decline. Underlying mechanisms include toxic effects of pesticides on non-target organisms and reductions in...  相似文献   

Increase in Iron and Zinc Concentrations in Rice Grains Via the Introduction of Barley Genes Involved in Phytosiderophore Synthesis   总被引：1，自引：1，他引：0  

Hiroshi Masuda  Motofumi Suzuki  Kendi Claudio Morikawa  Takanori Kobayashi  Hiromi Nakanishi  Michiko Takahashi  Masahiko Saigusa  Satoshi Mori  Naoko K. Nishizawa 《Rice》2008,1(1):100-108

Increasing the iron (Fe) and zinc (Zn) concentrations of staple foods, such as rice, could solve Fe and Zn deficiencies, which are two of the most serious nutritional problems affecting humans. Mugineic acid family phytosiderophores (MAs) play a very important role in the uptake of Fe from the soil and Fe transport within the plant in graminaceous plants. To explore the possibility of MAs increasing the Fe concentration in grains, we cultivated three transgenic rice lines possessing barley genome fragments containing genes for MAs synthesis (i.e., HvNAS1, HvNAS1, and HvNAAT-A and HvNAAT-B or IDS3) in a paddy field with Andosol soils. Polished rice seeds with IDS3 inserts had up to 1.40 and 1.35 times higher Fe and Zn concentrations, respectively, compared to non-transgenic rice seeds. Enhanced MAs production due to the introduced barley genes is suggested to be effective for increasing Fe and Zn concentrations in rice grains.  相似文献   

Map- vs. homology-based cloning for the recessive gene ol-2 conferring resistance to tomato powdery mildew     

Stefano Pavan  Zheng Zheng  Mariya Borisova  Petra van den Berg  Concetta Lotti  Claudio De Giovanni  Pim Lindhout  Hans de Jong  Luigi Ricciardi  Richard G. F. Visser  Yuling Bai 《Euphytica》2008,162(1):91-98

The recessive gene ol-2 confers papilla-associated and race-non-specific resistance to tomato powdery mildew caused by Oidium neolycopersici. In order to facilitate marker assisted selection (MAS) in practical breeding programmes, we identified two simple sequence repeat (SSR) markers and one cleaved amplified polymorphic sequence (CAPS) marker which are linked to the resistance locus and co-dominantly inherited. Aiming to provide a base for ol-2 positional cloning, we used a large segregating F₂ population to merge these markers with all the ol-2 linked amplified fragment length polymorphism (AFLP^®) markers previously identified in an integrated genetic map. By screening a tomato bacterial artificial chromosome (BAC) library, we detected two BAC clones containing two expressed sequence tags (ESTs) homologous to the gene mlo, responsible for powdery mildew resistance in barley, as well as an ol-2-linked marker. Chromosomal mapping by Fluorescence in situ Hybridization (FISH) revealed major signals of the two BAC DNAs in the pericentromeric heterochromatin of the short arm of chromosome 4, in the same region where the ol-2 gene was previously mapped. The genetic and cytogenetic co-localisation between ol-2 and tomato mlo-homologue(s), in addition to the similarity of ol-2 and mlo resistances for both genetic and phytopathological characteristics, suggests that ol-2 is likely a mlo-homologue. Thus, a homology-based cloning approach could be more suitable than positional cloning for ol-2 isolation.  相似文献   

A natural fungicide for the control of <Emphasis Type="Italic">Erysiphe betae</Emphasis> and <Emphasis Type="Italic">Erysiphe cichoracearum</Emphasis>     

Domenico Rongai  Claudio Cerato  Luca Lazzeri 《European journal of plant pathology / European Foundation for Plant Pathology》2009,124(4):613-619

This study examines the effects of a vegetable fungicide on sugar beet powdery mildew (Erysiphe betae) and cucumber powdery mildew (Erysiphe cichoracearum). The formulations consisting of a dispersion of Brassicaceae meal in vegetable or mineral oils on infected leaves of sugar beet, reared in the greenhouse, and of musk melons cultivated under plastic tunnels, were tested in comparison to each oil taken separately. Both formulations containing Brassicaceae meals, caused 94% of conidia to be distorted while for the untreated group only 2% were distorted. Furthermore, the leaf area infected by E. betae was 56% for untreated plants and 2.7 and 9.9% respectively, for plants treated with meal containing mineral and vegetable oil. Vegetable oil considered separately or with Brassicaceae meals showed no phytotoxicity, while the formulations based on mineral oil showed a significantly lower fresh and dry weight on tomato plants. The low level or absence of phytotoxicity of plants treated with vegetable oil formulations suggests that to improve the efficacy of powdery mildew control, they could be used mixed with sulphur. The efficiency of the vegetable formulations in the powdery mildew control observed during these trials encourages further investigation on other parasitic fungi and foliar pathogens.  相似文献   

Management of feral domestic cats in the urban environment of Rome (Italy)     

Natoli E  Maragliano L  Cariola G  Faini A  Bonanni R  Cafazzo S  Fantini C 《Preventive veterinary medicine》2006,77(3-4):180-185

In Italy, which is rabies-free, the national Law No. 281 [Legge Nazionale 14 agosto 1991. No. 281: Legge Quadro in materia di animali di affezione e prevenzione del randagismo. Gazz. Uff. Rep. Ital. no 203 del 30 agosto 1991: p. 3] on the management of pets and on the control of feral cats has introduced the no-kill policy for this species. Thus, “trap-neuter-release” (TNR) programs have been carried out for >10 years. In this paper we present data on registered colonies and censused cats in Rome from 1991 to 2000; the results of the neutering campaign from 1991 to 2000; and a survey, on 103 cat colonies, on the effects of demographic control of urban feral-cat colonies in the city of Rome, carried out by the local Veterinary Public Services (VPS) in collaboration with the associations of cat care-takers. In 10 years almost 8000 were neutered and reintroduced in their original colony. The spay/neuter campaigns brought about a general decrease in cat number but the percentage of cat immigration (due to abandonment and spontaneous arrival) is around 21%. This suggests that all these efforts without an effective education of people to control the reproduction of house cats (as a prevention for abandonment) are a waste of money, time and energy.  相似文献   

Detection of a broad range of class I and II Newcastle disease viruses using a multiplex real-time reverse transcription polymerase chain reaction assay.     

L Mia Kim  David L Suarez  Claudio L Afonso 《Journal of veterinary diagnostic investigation》2008,20(4):414-425

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Open‐label clinical trial of rectally administered levetiracetam as supplemental treatment in dogs with cluster seizures     

Giulia Cagnotti  Rosangela Odore  Iride Bertone  Cristiano Corona  Elena Dappiano  Giulia Gardini  Barbara Iulini  Claudio Bellino  Antonio D'Angelo 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(4):1714-1718

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The challenge of large litters on the immune system of the sow and the piglets     

Claudio Oliviero  Sami Junnikkala  Olli Peltoniemi 《Reproduction in domestic animals》2019,54(Z3):12-21

The use of hyperprolific sow lines has increased litter size considerably in the last three decades. Nowadays, in some countries litters can reach up to 18–20 piglets being a major challenge for the sow's physiology during pregnancy, parturition and lactation. The increased number of piglets born per litter prolongs sensibly the duration of farrowing, decreases the piglets’ average weight at birth and their vitality, increases the competition for colostrum intake and can affect negatively piglets’ survival. This review aims to describe how large litters can affect the immune system of the sow and the piglets and proposes measures to improve this condition.  相似文献