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91.
The effects of the sterol biosynthesis inhibitor (SBI) fungicides fenarimol, fenpropimorph, imazalil, prochloraz, propiconazole and triadimenol on growth and sterol composition of Ustilago maydis, Botrytis cinerea and Pyrenophora teres, grown from spores or sporidia in liquid culture, were determined. Growth of U. maydis was only slightly inhibited by SBI fungicides at concentrations which caused considerable changes in both sterol content and composition. Conversely, in B. cinerea and P. teres, growth was strongly inhibited under conditions where ergosterol was still the predominant sterol, suggesting that, in these two fungi, growth may be more sensitive to SBI fungicides than overall sterol production. Demethylase inhibitor fungicides behaved as a homogeneous group in their effects on growth and on sterol profiles of the three fungi studied. 相似文献
92.
Uptake and translocation of 26 chemicals (herbicides, fungicides, growth regulators, insecticides and model compounds), formulated with and without ‘Ethylan TU’ (NP8) surfactant, have been determined 24, 48 and 72 h after spraying onto leaves of maize, rape, strawberry and sugar beet. Eight of the chemicals may be classified as polar (log partition coefficient (P) < 0) and 18 as lipophilic (log P 0·8-4·6). Chemicals penetrated more readily into waxy leaves of rape and strawberry than into less-waxy sugar beet, whilst lowest rates were observed for maize. Rates of uptake varied from exceedingly low (< 2% 72 h after application) for uracil, maleic hydrazide, isoproturon and methyl phenylurea applied to maize, to rapid (>98% within 24 h of application) for acephate and triadimefon applied to strawberry leaves. The effects of NP8 on rates of chemical uptake were classified into 4 types, viz:-
- (i) low rates, with limited enhancement by NP8;
- (ii) high rates unaffected by NP8;
- (iiii) marked enhancement by NP8 within 24 h; and
- (iv) continuous enhancement by NP8 over 0-72 h.
93.
94.
Performance evaluation and validation of the animal trauma triage score and modified Glasgow Coma Scale with suggested category adjustment in dogs: A VetCOT registry study 下载免费PDF全文
95.
Easily-measured site variables (e. g. absolute elevation, exposure, slope and aspect) were used to prepare different regression models to predict the extent and severity of attack by C. sororia on a number of different provenances of lodgepole pine. Using a simple climatic-zone division of Scotland, a significant relationship between percentage infection on whorls 1–5, 6–10 and 11–15 and elevation, exposure and site aspect was demonstrated, whereas severity of infection was not well related with these variables in any of the models tested. This suggests that severity of infection may be influenced by other independent variables, e. g. persistence of liquid water on bark, success of spore germination and host resistance. This approach offers an opportuity to predict the possible susceptibility of different provenances of lodgepole pine under specific site conditions. 相似文献
96.
Nodal cankers caused by C. sororia on Corsican pine were three times as common as internodal cankers. Natural infections reached maximum incidence on the fourth internode from the apex in branches and stems, but on stem internodes only on the ninth internode down. The longitudinal rate of canker spread was approximately 4 times that of the tangential rate. Crops of Corsican pine on N-facing slopes were more severely infected than those on S-facing slopes or flat areas, but in all cases the frequency of infection increased progressively with crop age. Cankers on individual stems showed a highly significant concentration on Northerly and Easterly aspects. Evidence is presented which suggests that the temperature differentials observed on different sectors of tree trunks may influence the duration of water films and hence limit the time period during which spore germination is possible. 相似文献
97.
98.
S. Nair S. E. Ullrich T. K. Blake B. Cooper C. A. Griffey P. M. Hayes D. J. Hole R. D. Horsley D. E. Obert K. P. Smith G. J. Muehlbauer B.‐K. Baik 《Cereal Chemistry》2010,87(5):461-466
Kernel hardness is an important trait influencing postharvest handling, processing, and food product quality in cereal grains. Though well‐characterized in wheat, the basis of kernel hardness is still not completely understood in barley. Kernels of 959 barley breeding lines were evaluated for hardness using the Single Kernel Characterization System (SKCS). Barley lines exhibited a broad range of hardness index (HI) values at 30.1–91.9. Distribution of kernel diameter and weight were 1.7–2.9 mm and 24.9–53.7 mg, respectively. The proportion of hull was 10.2–20.7%. From the 959 breeding lines, 10 hulled spring barley lines differing in HI values (30.1–91.2) were selected to study the associations of HI with proportion of hull, kernel weight, diameter, vitreousness, protein, β‐glucan, and amylose content. Vitreousness, evaluated visually using a light box, showed a clear distinction between hard and soft kernels. Hard kernels appeared translucent, while soft kernels appeared opaque when illuminated from below on the light box. Kernel brightness (L*), determined as an indicator of kernel vitreousness, showed a significant negative correlation (r = –0.83, P < 0.01) with HI. Protein, β‐glucan, amylose content, proportion of hull, kernel weight, and diameter did not show any significant association with HI. 相似文献
99.
Johnie N. Jenkins Jack C. McCarty Martin J. Wubben Russell Hayes Osman A. Gutierrez Franklin Callahan Dewayne Deng 《Euphytica》2012,183(1):49-54
Cotton (Gossypium hirsutum L) cultivars highly resistant to the southern root-knot nematode (RKN) [Meloidogyne incognita (Kofoid and White) Chitwood] are not available. Resistant germplasm lines are available; however, the difficulty of selecting
true breeding lines has hindered applied breeding and no highly resistant cultivars are available to growers. Recently, molecular
markers on chromosomes 11 and 14 have been associated with RKN resistance, thus opening the way for marker assisted selection
(MAS) in applied breeding. Our study aimed to determine the utility of these markers for MAS. Cross one was RKN resistant
germplasm M240 RNR × the susceptible cultivar, FM966 and is representative of the initial cross a breeder would make to develop
a RKN resistant cultivar. Cross two consists of Clevewilt 6 × Mexico Wild (PI563649), which are the two lines originally used
to develop the first highly RKN resistant germplasm. Mexico Wild is photoperiodic. We phenotyped the F2 of cross one for gall index and number of RKN eggs per plant and genotyped each plant for CIR 316 (chromosome 11) and BNL
3661 (chromosome 14). From this, we verified that MAS was effective, and the QTL on chromosome 14 was primarily associated
with a dominant RKN resistance gene affecting reproduction. In the first F2 population of cross two, we used MAS to identify 11 plants homozygous for the markers on chromosomes 11 and 14, and which
also flowered in long days. Progeny of these 11 plants were phenotyped for RKN gall index and egg number and confirmed as
RKN highly resistant plants. Generally about 7–10 generations of RKN phenotyping and progeny testing were required to develop
the original RKN highly resistant germplasms. Our results show that commercial breeders should be able to use the markers
in MAS to rapidly develop RKN resistant cultivars. 相似文献
100.
Bommer NX Hayes AM Scase TJ Gunn-Moore DA 《Journal of Feline Medicine and Surgery》2012,14(8):527-533
Records of 11 cats with transitional cell carcinoma of the urinary bladder, which had been treated with meloxicam, were reviewed for signalment, duration of clinical signs prior to diagnosis, results of diagnostic imaging, whether or not concurrent surgery was performed and survival. Immunohistochemical expression of cyclo-oxygenase-1 (COX-1) and cyclo-oxygenase-2 (COX-2) was assessed in the tumours of seven cats. Tumour location varied greatly. The cats had a mean age of 13 years. Three cats had a previous diagnosis of feline idiopathic cystitis of up to 2008 days duration. Ten of the cats showed clinical improvement (reduction of haematuria and/or dysuria), with a mean survival time (MST) of 311 days (range 10-1064); 1-year survival of 50%. All seven bladders assessed for COX staining were COX-1 positive and five were COX-2 positive. The MST for the COX-2-positive cats was 123 days, the MST for the COX-2-negative cases was 375 days. 相似文献