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11.
Resistance to Botrytis cinerea in Solanum lycopersicoides is Dominant in Hybrids with Tomato, and Involves induced Hyphal Death 总被引:2,自引:0,他引:2
Rejane L. Guimarães Roger T. Chetelat Henrik U. Stotz 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(1):13-23
Botrytis cinerea causes gray mold disease and affects hundreds of plant species, including tomato (Lycopersicon esculentum). The wild nightshade, Solanum lycopersicoides, is cross compatible with tomato and is more resistant to B. cinerea, thus representing a potential source for crop improvement. Tests involving droplet inoculation of detached leaves and spray inoculation of entire seedlings demonstrated that resistance to B. cinerea varies among S. lycopersicoides accessions, with S. lycopersicoides LA2951 being the most resistant accession tested. Expression of resistance in the intergeneric hybrid (L. esculentum cv. 'VF36' × S. lycopersicoides LA2951) suggested that resistance is at least partially dominant in tomato. A green fluorescent protein-tagged B. cinerea strain was used for confocal microscopic comparison of infection in leaves of S. lycopersicoides and tomato. Even though S. lycopersicoides supported spore germination, there was evidence for hyphal lysis and death 3 days after inoculation, at a time when lesions were expanding on susceptible tomato plants. The reduced frequency of B. cinerea lesion spread on S. lycopersicoides explains why this fungus produced fewer spores in this wild nightshade than in tomato. 相似文献
12.
F.J. López-Escudero C. del Río J.M. Caballero M.A. Blanco-López 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(1):79-85
Resistance of 23 important olive cultivars to Verticillium dahliae has been evaluated in four experiments under controlled conditions. Nine-month-old nursery olive plants were inoculated with a cotton non-defoliating (ND) (V4) or a cotton defoliating (D) (V117) isolate of V. dahliae. Resistance was evaluated by assessing symptom severity using a 0–4 rating scale and estimating the area under disease progress curves. The percentage of plants killed and of those which recovered from the disease were used as additional parameters for including a particular cultivar into a defined category. Most of the evaluated cultivars were susceptible, although at different levels, to both isolates of V. dahliae. All cultivars were more susceptible to the D pathotype than to the ND one. A group of 11 cultivars, including several important Spanish cultivars, were susceptible or extremely susceptible to both pathotypes of V. dahliae. A second group showed differences of resistance depending on the pathotype used. They were susceptible or extremely susceptible to the D pathotype but resistant or moderately susceptible to the ND one. Finally, 'Frantoio', 'Oblonga' and 'Empeltre' were moderately susceptible to the D isolate of V. dahliae and resistant to the ND one. The resistance of 'Empeltre' was evident by the plant ability to recover from infection with either isolates. 'Empeltre' is considered to be a valuable cultivar for inclusion in breeding programmes for resistance to Verticillium wilt. 相似文献
13.
A. L. Echemendía P. L. Ramos L. Díaz R. Peral A. Fuentes M. Pujol G. González 《Plant pathology》2004,53(2):234-234
14.
Morphofunctional description of mucous cells in the gills of the Arapaimidae Arapaima gigas (Cuvier) during its development 下载免费PDF全文
C. A. Ramos O. T. F. da Costa W. L. P. Duncan M. N. Fernandes 《Anatomia, histologia, embryologia》2018,47(4):330-337
The gill structure of the Amazonian fish Arapaima gigas (Cuvier 1829) shows ontogenetic changes during development, particularly due the transition from the aquatic to the obligatory air breathing mode of respiration. However, three main cell types can be found in the gills: mitochondrial rich cells, pavement cells and mucous cells (MCs). The MCs are involved in the secretory pathway. The functions of the secreted molecules include mechanical protection of epithelia, protection against parasites and bacterial infection, and role on ion regulation. In this study, we analysed mucous cell location and mucous cell type, based on pH, during the development of A. gigas. Using samples obtained from the environment, gills were collected and fixed in buffered solution. Histological techniques for the identification of MCs were performed Alcian Blue (AB) and periodic acid‐Schiff (PAS). The results showed the presence of PAS+ and AB+ cells in the whole filament in all examined fish. In animals less than 50 g, few MCs were present, and no differences were observed in AB+ and PAS+ cells. In animals weighing close to 500 g, more PAS+ cells than AB+ cells were observed, and in animals that weighed more than 1,000 g, more AB+ cells than PAS+ cells were observed. These observations may be a result of the ontogenetic changes in the gill epithelia, which can change the osmorespiratory compromise in ion regulation functions as well the glycosaminoglycans secreted by PAS cells, which in large animals can play a role in the protection against parasites and bacterial infection. 相似文献
15.
Hindlimb bone maturation during postnatal life in the Greater Rhea (Rhea americana,Aves, Palaeognathae): Implications for palaeobiological and zooarchaeological interpretations 下载免费PDF全文
Mariana B. J. Picasso Claudio Gustavo Barbeito 《Anatomia, histologia, embryologia》2018,47(5):398-404
The objective of this study was to study the morphological pattern of bone maturation of the hindlimb bones of Rhea americana and find out how it can affect bone morphology after a taphonomic process. Juvenile specimens (n = 10) ranging from one month old to eight months old were studied. For comparison, bones from adults and juveniles from museum specimens (n = 4 and n = 6, respectively) were studied. In fresh bones, ossification centres were identified in the proximal and distal epiphyses of the tibiotarsi and in the proximal epiphysis of the tarsometatarsi, whereas the distal region of the femora and tarsometatarsi showed abundance of cartilage. The development and extension of the ossification centres of the tibiotarsi were different. In the proximal epiphysis, the centre presented less development with respect to the distal epiphysis. In the dry tibiotarsi, the proximal centre was absent and the distal one was well preserved. Both the fresh and dry juvenile tarsometatarsi presented unfused metatarsals and bulkier and wider aspect than the adult ones. The dry femora presented a noticeable excavation between condyles, whereas the dry tarsometatarsi showed the absence of the proximal epiphysis. The femora, tibiotarsi and tarsometatarsi possessed different traits of immaturity, which differentially affect the morphology of the preserved bones during a taphonomic process. 相似文献
16.
Fortes Maira Salomão Lopes-Mori Fabiana Maria Ruiz Caldart Eloiza Teles Constantino Caroline Evers Fernanda Pagliari Sthefany de Almeida Jonatas Campos Barros Luiz Daniel Freire Roberta Lemos Garcia João Luis Headley Selwyn Arlington Navarro Italmar Teodorico 《Tropical animal health and production》2018,50(2):413-419
Tropical Animal Health and Production - This study investigated the prevalence of caprine toxoplasmosis in goat herds from Southern Brazil by the indirect immunofluorescence assay (IFA), and... 相似文献
17.
de Carvalho Menezes de Almeida Sheylla Foligno Souza-Fabjan Joanna Maria Gonçalves Balaro Mario Felipe Alvarez Bragança Gláucia Mota Pinto Pedro Henrique Nicolau de Almeida José Gabriel Moura Ana Beatriz Bossois da Fonseca Jeferson Ferreira Brandão Felipe Zandonadi 《Tropical animal health and production》2018,50(2):427-432
Tropical Animal Health and Production - This study evaluated the effect of two doses of prostaglandin at different intervals on reproductive parameters of crossbred ewes. In Experiment 1, 30 ewes... 相似文献
18.
Paixão Sonália Ferreira Fritzen Juliana Torres Tomazi Crespo Sarah Elizabeth Izzo de Moraes Pereira Helder Alfieri Alice Fernandes Alfieri Amauri Alcindo 《Tropical animal health and production》2018,50(8):1947-1950
Tropical Animal Health and Production - Serological studies have characterized the presence of the bovine viral diarrhea virus (BVDV) infection in water buffalo herds worldwide. However, the... 相似文献
19.
Lucíola Vilarim Ferraz Adriana Guim Robson Magno Liberal Véras Francisco Fernando Ramos de Carvalho Marciela Thais Dino de Freitas 《Tropical animal health and production》2018,50(2):309-315
The effects of corn replacement by cassava dreg in diets of crossbred goat kids were evaluated. We tested the impacts of 0, 33, 66 and 100% replacement on intake, digestibility, feeding behaviour, performance and carcass characteristics. Thirty-six goat kids, aged between 4 and 5 months and with initial body weights of 17.61 ± 1.98 kg, were used in a completely randomised design. Analysis of regression revealed a negative linear effect on neutral detergent fibre (NDF) intake and a positive linear effect on non-fibrous carbohydrates (NFC) and hydrocyanic acids (HCN) intake. Cassava dreg use had a positive linear effect on organic matter digestibility and non-fibrous carbohydrates. Based on our results, cassava dreg use did not negatively impact animal performance, feeding behaviour and carcass characteristics, suggesting that it may replace corn up to 100% in the diets of confined goat kids. 相似文献
20.
RO Pinho BS Camilo DMA Lima FAC Villadiego JCM Vergara HH Shiomi RE Cardoso PS Lopes JD Guimarães 《Reproduction in domestic animals》2018,53(2):393-400
The objective was to study the use of ultrasound as a complementary test in the breeding soundness evaluation in male pigs and study the pattern of echogenicity of the testicular parenchyma in boars of different racial groups. Twenty‐six adult boars from four different racial groups were used, 10 from the Piau breed (group 1), four from the commercial and finishing group (group 2), six Pietrain breed (group 3) and six from the Duroc breed (group 4). All animals were evaluated for breeding soundness evaluation and the ultrasound examination of the testicles. The groups of animals that were evaluated showed no difference in the main semen parameters that were evaluated, except for the sperm volume, concentration of the ejaculated sperm and the supravital staining; the lowest figures were for the animals from the Piau breed (group 1). In relation to the testicular biometrics, Duroc animals (group 4) had a greater scrotal width compared to the other groups. But when we assessed the intensity of pixels of the testicles, there was a difference between groups. The groups 2 (finishing animals), 3 (Pietrain) and 4 had no difference between themselves. Group 3 had greater pixel intensity in relation to group 1. Of the 26 animals studied, five showed an abnormality during ultrasound evaluation, like hydrocele, hyperechoic mass in the testicular parenchyma, cyst in the head of the epididymis and the presence of fluid in the head and tail of the epididymis. The various animal groups studied did not differ in the principal reproductive parameters evaluated, showing that despite the great variability of reproductive traits between breeds and within the same breed, the breeding soundness evaluation, the more complete it is, is essential for the selection of breeders and the ultrasonography of the reproductive system becomes an important addition in this examination. 相似文献