Protection of olive planting stocks against parasitism of root-knot nematodes by arbuscular mycorrhizal fungi   总被引：3，自引：0，他引：3  

P. Castillo  A. I. Nico  C. Azcón-Aguilar  C. Del Río Rincón  C. Calvet  R. M. Jiménez-Díaz 《Plant pathology》2006,55(5):705-713

The effects were investigated, under controlled conditions, of single and joint inoculation of olive planting stocks cvs Arbequina and Picual with the arbuscular mycorrhizal fungi (AMF) Glomus intraradices , Glomus mosseae or Glomus viscosum , and the root-knot nematodes Meloidogyne incognita and Meloidogyne javanica , on plant performance and nematode infection. Establishment of the fungal symbiosis significantly increased growth of olive plants by 88·9% within a range of 11·9–214·0%, irrespective of olive cultivar, plant age and infection by M. incognita or M. javanica . In plants free from AMF, infection by Meloidogyne spp. significantly reduced the plant main stem diameter by 22·8–38·6%, irrespective of cultivar and plant age. Establishment of AMF in olive plants significantly reduced severity of root galling by 6·3–36·8% as well as reproduction of both Meloidogyne spp. by 11·8–35·7%, indicating a protective effect against parasitism by root-knot nematodes. Infection by the nematodes influenced root colonization by AMF, but the net effect depended on the AMF isolate–olive cultivar combination. It is concluded that prior inoculation of olive plants with AMF may contribute to improving the health status and vigour of cvs Arbequina and Picual planting stocks during nursery propagation.  相似文献   

Observations on the potential of microwaves for weed control     

I SARTORATO  G ZANIN†  C BALDOIN‡  & C DE  ZANCHE‡ 《Weed Research》2006,46(1):1-9

Field tests of a prototype microwave‐based weed killer machine were conducted on Abutilon theophrasti, Panicum miliaceum, lucerne and oilseed rape pure stands. The approach can be considered a thermal weed control method, the microwave radiation causing dielectric heating of plant tissue water that eventually kills the plant. The method could overcome the limitations of other thermal methods, such as fire risk with flaming or the heavy loads required for hot water treatments. Species were effectively controlled by microwave irradiation, but their sensitivity and the evolution of damage symptoms over time differed. Lucerne showed no sigmoidal response and was the least affected by the treatment, while a log‐logistic curve expressed the dose–response relationships of the other species quite well. The estimated microwave dose for a 90% dry weight reduction ranged from 1015 kJ m^?2 in A. theophrasti to 3433 kJ m^?2 in P. miliaceum. Energy cost evaluation indicated that increased efficiency is required for this technique to compete with other thermal methods. Microwave efficiency could be increased by a flux configuration that minimizes soil penetration and maximizes absorption by plants, which, in turn, depends on plant growth form.  相似文献   

Note: Molecular identification of three entomopathogenic nematodes from turkey by PCR-RFLP of the ITS regions     

I. Alper Susurluk  Umut Toprak 《Phytoparasitica》2006,34(1):17-20

Molecular identification methods are widely used for the classification of organisms worldwide. Entomopathogenic nematodes are the most often isolated insect parasitic nematodes in the tropical and subtropical regions. In our investigation, PCR-RFLP (Polymerase Chain Reaction — Restriction Fragment Length Polymorphism) of the ITS region (Internal Transcribed Spacer) on the ribosomal (r) DNA of three entomopathogenic nematodes isolated from Ankara, Turkey, was analyzed for identification. The ITS region of rDNA was amplified by PCR and then digested with the following nine restriction enzymes: Alu I, Dde I, Hae III, Hha I, Hind III, Hinf I, Hpa II, Rsa I and Sau 3AI. The amplified and restricted sequences of the ITS regions were separated by agarose gel electrophoresis and the RFLP patterns of these three species were shown in this study. According to our results, these species were identified asSteinernema feltiae, Steinernema carpocapsae andHeterorhabditis bacteriophora. http://www.phytoparasitica.org posting Nov. 4, 2005.  相似文献   

Application of bovine microsatellite markers for genetic diversity analysis of European bison (Bison bonasus)     

T. Roth  I. Pfeiffer  K. Weising  & B. Brenig 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2006,123(6):406-409

In this study, the cross‐amplification of a commercial multiplex set of 11 cattle (Bos taurus) microsatellites was tested on a panel of 35 European bison (Bison bonasus) individuals. After polymerase chain reaction optimization, all loci cross‐amplified successfully in investigated bisons. Number of alleles and observed and expected heterozygosity per locus are in the range of 2–4, 0.086–0.629 and 0.288–0.621 respectively. The availability of a heterologous set of multiplexed microsatellite markers derived from cattle opens an avenue for collecting profound genetic data for efficient conservation management strategies of the European bison.  相似文献   

Semen Technologies in Dog Breeding: an Update     

FJ Peña  I Núñez-Martínez  JM Morán 《Reproduction in domestic animals》2006,41(S2):21-29

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The separate effects of the nature of diet and grazing mobility on metabolic potential of muscles from Charolais steers   总被引：1，自引：0，他引：1  

C. Jurie  I. Ortigues-Marty  B. Picard  D. Micol  J.F. Hocquette 《Livestock Science》2006,104(1-2):182-192

The objectives of the two experiments presented were to determine the separate effects of diet and mobility associated with grazing on the metabolic potential of muscles of Charolais steers reared at similar growth rates and slaughtered at the same age (31 months on average).Glycolytic [lactate dehydrogenase (LDH), phosphofructokinase (PFK)] and oxidative [β-hydroxyacyl-CoA dehydrogenase (HAD), citrate synthase (CS), isocitrate dehydrogenase (ICDH), cytochrome c oxidase (COX)] enzyme activities were measured spectrophotometrically in semitendinosus (ST), a glycolytic muscle, and rectus abdominis (RA), an oxidative muscle.In Experiment 1, 24 weaned steers were assigned to two groups: grazing grass (GG) and maize silage (MS). In Experiment 2, 30 weaned steers were assigned to five groups: grazing grass (GG), cut grass without walking (CG), cut grass with walking (CGW), maize silage without walking (MS) and maize silage with walking (MSW). Both experiments lasted for 2 years. All grass fed animals were fed grass silage during the two winter seasons. During the two summer seasons, GG steers were grazing and did not receive any supplementation while CG and CGW steers were fed indoor freshly cut grass alone. MS and MSW steers were fed maize silage indoor during the entire experiment. For the second summer before slaughter, half of the indoor fed steers on each type of diet (CGW and MSW groups) was submitted 7 days a week to a 5.2 km walk daily.At slaughter, carcass weight and composition did not differ between groups. Oxidative HAD, CS and ICDH enzyme activities were higher for GG, as compared with MS group, in RA muscle in both experiments (P < 0.05 to 0.01) and in ST muscle (P < 0.05) in Experiment 2. Muscles from the GG group were thus more oxidative than those of the MS group. It was further tested whether these effects could be specifically attributed to the nature of the diet or to differences in mobility. A cut grass diet (vs. maize silage) increased HAD and ICDH activities (P < 0.05) and mobility induced by walking increased HAD and CS (P < 0.01) activities. In conclusion, the more oxidative metabolic orientation of muscles of grazing steers originates from a combination of two effects: an increase mobility at pasture and a grass (vs. maize silage)-based diet.  相似文献   

Evaluation of the efficiency of alternative two-tier nucleus breeding systems designed to improve meat sheep in Kenya   总被引：1，自引：0，他引：1  

M.G. Gicheha  I.S. Kosgey  B.O. Bebe  & A.K. Kahi 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2006,123(4):247-257

A deterministic approach was used to genetically and economically evaluate the efficiency of five two‐tier nucleus breeding systems for meat sheep in Kenya. The nucleus breeding systems differed in terms of whether the system was closed or open, in the type of animals that were involved in the movement of genetic superiority and in the number of selection pathways in each system. These systems were compared under four alternative breeding objectives based on monetary genetic gain and profit per ewe. The first objective simulated a situation where the flock size cannot be increased due to non‐feed related constraints (FLOCK). The second specifically assumed that the flock size is restricted due to limited amount of feed resources (FEED). The third and fourth objectives assumed that sheep performed only tangible roles (TR) and both tangible and intangible roles (IR) in the production system respectively. Monetary genetic gains were highest for all objectives in an open nucleus system with a certain proportion of commercial‐born ewes being introduced in the nucleus while at the same time utilizing young rams from the nucleus to breed sires and dams for the nucleus and commercial sector (ONyre). Utilizing young rams in a closed nucleus system for the dissemination of superior genes resulted in higher annual monetary genetic gain than utilization of old rams. Profit per ewe was significantly higher for FLOCK and IR in ONyre. In a closed system that allowed for downward movement of dams from the nucleus to the commercial sector to breed sires and dams, profit per ewe was highest for FEED and TR. The success of a nucleus breeding system should also focus on the profitability and logistics of establishing it. The implication of these results on the choice of two‐tier nucleus breeding systems for the improvement of meat sheep is discussed.  相似文献   

Low temperature storage and in vitro germination of cherimoya (Annona cherimola Mill.) pollen     

J. Lora  M.A. Pérez de OteyzaP. Fuentetaja  J.I. Hormaza 《Scientia Horticulturae》2006

Due to the protogynous dichogamy of cherimoya and to the absence of proper pollinating vectors, hand-pollination with fresh pollen is a common practice for cherimoya commercial production. In order to optimize the process of hand-pollination, in this work we have studied the conservation of cherimoya pollen at −20, −80 and −196 °C for up to 3 months. In vitro pollen germination of fresh pollen was 57.1% and it was progressively reduced with conservation time at the three temperatures studied reaching a minimum after 3 months of storage of 10.4%, 14.2% and 13.6% at −20, −80 and −196 °C, respectively. Differences in germination among temperatures were only significant during the first 2 weeks of storage. Field pollinations with pollen stored for up to 3 months at the three temperatures show no yield differences compared to pollinations performed with fresh pollen. The results indicate that pollen collected and stored at sub-zero temperatures at the beginning of the cherimoya blooming season can be used along the whole blooming season avoiding the need of collecting fresh pollen daily.  相似文献   

Note: Pyrethroid resistance and possible involvement of glutathione<Emphasis Type="Italic">S</Emphasis>-transferases in<Emphasis Type="Italic">Helicoverpa armigera</Emphasis> from Turkey     

Sakine Ugurlu  Metin Konus  Belgin Isgor  Mesude Iscan 《Phytoparasitica》2007,35(1):23-26

An introductory study was conducted to investigate the pyrethroid resistance ofHelicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) strains in Turkey, collected from cotton fields in the Adana and Antalya provinces, through two different synthetic pyrethroid insecticides: lambda-cyhalothrin and esfenvalerate. In addition, the roles of glutathioneS-transferases (GSTs) in this resistance mechanism were analyzed. It was found that whereas resistance ratios for lambda-cyhalothrin (LD₅₀ levels) were 3- and 98-fold increased in the Adana and Antalya strains, respectively, esfenvalerate ratios were 3.3- and 92.3-fold increased in the Adana and Antalya strains, respectively, with respect to the susceptible strain. Furthermore, Adana and Antalya strains showed 2.4- and 2.9-fold higher GST activities than the susceptible strain, respectively. In the Antalya field strain, the minor increase in GST activity compared with the resistance levels implies that GSTs may be not greatly involved in this resistance. It also provides evidence that they could not be the only metabolic mechanism responsible for resistance to lambda-cyhalothrin and esfenvalerate inH. armigera from Turkey. http://www.phytoparasitica.org posting Nov. 16, 2006.  相似文献   

Dhan Pal Singh and Arti Singh,Disease and Insect Resistance in Plants     

Christine Struck 《European journal of plant pathology / European Foundation for Plant Pathology》2007,118(1):91-92

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