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1.
Farnaz Kordbacheh Charles L. Mohler Alan G. Taylor Anna S. Westbrook Hamid Rahimian-Mashhadi Hassan M. Alizadeh Antonio DiTommaso 《Weed Research》2023,63(1):34-44
Abutilon theophrasti (velvetleaf) is a widespread and problematic annual weed. Greenhouse and field experiments were conducted to investigate the effects of different cutting methods on the viability of A. theophrasti seeds. Three cutting methods were assessed: (1) Entire plant cut and dried (EPD)—plants were cut at soil level and dried with capsules attached on the greenhouse bench or soil surface for 4 weeks; (2) capsules detached and dried (CD)—capsules were removed from plants and dried for 4 weeks; and (3) capsules detached and tested while fresh (CF)—a control treatment. Before drying, the developmental stage (stage one, dark green; stage two, light green; stage three, yellowish-green; or stage four, black with the slightly open capsule) and age (days after flowering, DAF) of each capsule was recorded. Seed viability was measured immediately in the CF treatment and after the 4-week drying period in the EPD and CD treatments. No seeds in the EPD and CD treatments were viable when harvested at the first developmental stage (1–8 DAF) in either experiment, but 100% of seeds in the CF treatment in the field were viable when harvested at 8 DAF. In both greenhouse and field experiments, seeds attained full viability at earlier harvest ages in CF than in EPD or CD treatments, suggesting that seeds might become viable relatively early in development but lose viability if allowed to dry. These findings could be applied to optimise late-season mechanical control of A. theophrasti. 相似文献
2.
Malik Muniba Abid Munir Haider Muhammad Saleem Zhai Ying Khan Muhammad Azmat Ullah Pappu Hanu R. 《植物病害和植物保护杂志》2023,130(1):23-33
Journal of Plant Diseases and Protection - Mastreviruses are an emerging group of viruses transmitted by leafhoppers and infect both monocot and dicot plants. Chickpea chlorotic dwarf virus... 相似文献
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Pentamidine treatment has been used successfully to establish immune cellular responses in recovered dogs. In this paper, we examined the appearance and disappearance of antibodies over time against crude Leishmania antigens and purified gp63 or gp70 proteins in sera from cured dogs using a Western blotting technique.Following the treatment, a pattern of antibody specificities to parasite antigens was observed in the sera of cured dogs. Antibodies to gp63 and gp70 were maintained after cure. In addition, the reaction with a 26 kD band observed during the clinical phase was no longer recognized by sera taken from recovery dogs. Interestingly, two proteins, 85 and 110 kD, not observed during the patent phase were detected by sera taken from treated dogs. Such patterns of antibody specificities to various parasite antigens might represent a useful parameter to determine the actual phase of the disease process. 相似文献
5.
Elzein S Hamid ME Quintana E Mahjoub A Goodfellow M 《DTW. Deutsche tier?rztliche Wochenschrift》2002,109(10):442-443
Four of 10 donkeys, which showed lesions simulating fistulous withers, were examined clinically with the aim to cultivate and identify the causal agent. Aspiated purulent materials were subjected to bacteriological examination. The causal organisms were recovered in Tryptic Soya agar medium when incubated aerobically at 37 degrees C for up to 5 days. These organisms were found to be actinomycetes-like, Gam positive with stable branching filaments and to form heavy aerial hyphae on colony surface. The isolated organisms ere tentatively identified as Streptomyces sp. on the basis of morphological and cultural characteristics. The initial sequences analysis of the 16S rDNA gene conformed that one of the isolates (SD551) falls within the phylogenetic clade, which encompasses the genus Streptomyces. Studies are underway to further describe the disease and its causal agent. The report represents a good evidence to incriminate Streptomyces in the aetiology of the fistulous withers. 相似文献
6.
Construction of a microarray specific to the chicken immune system: profiling gene expression in B cells after lipopolysaccharide stimulation 下载免费PDF全文
Aimie J. Sarson Leah R. Read Hamid R. Haghighi Melissa D. Lambourne Jennifer T. Brisbin Huaijun Zhou Shayan Sharif 《Canadian journal of veterinary research》2007,71(2):108-118
The objective of this study was to profile gene expression in cells of the chicken immune system. A low-density immune-specific microarray was constructed that contained genes with known functions in the chicken immune system, in addition to chicken-expressed sequence tags (ESTs) homologous with mammalian immune system genes, which were systematically characterized by bioinformatic analyses. Genes and ESTs that met the annotation criteria were amplified and placed on a microarray. The microarray contained 84 immune system gene elements. As a means of calibration, the microarray was then used to examine gene expression in chicken B cells after lipopolysaccharide stimulation. Differential gene expression was observed at 6, 12, and 24 h but not at 48 h after stimulation. The results were validated by semiquantitative polymerase chain reaction. The microarray showed a high degree of reproducibility, as demonstrated by intra- and interassay correlation coefficients of 0.97 and 0.95, respectively. Thus, the low-density microarray developed in this study may be used as a tool for monitoring gene expression in the chicken immune system. 相似文献
7.
Seed presoaking improves wheat germination under marginal moisture conditions. The duration of seed presoaking was studied at The University of Arid Agriculture, Rawalpindi, using 10 wheat varieties. Seed presoaking beyond 12 h does not improve germination further, and beyond 21 h, germination rate is drastically reduced. 相似文献
8.
In 3 urban areas in Selangor, Peninsular Malaysia between 1973 and 1981, blood from 4080 dogs was examined for haematozoa. The following frequencies were found: Babesia gibsoni 17.7%; microfilariae of Dirofilaria immitis 9.6%; Hepatozoon canis 1.2%; B. canis 1.1%; Ehrlichia canis 0.2%; Trypanosoma evansi 0.1%. A detailed examination of B. gibsoni infections and microfilariasis due to D. immitis with regards to monthly distribution, breed frequency, sex and age, revealed that pedigree and non-pedigree dogs were equally susceptible to Babesia and microfilariae infections. 相似文献
9.
Khazaeel Kaveh Pesarakli Hamid Mashhadi Alireza Ghadrdan Borujeni Mahdi Pourmahdi 《Veterinary research communications》2022,46(2):405-417
Veterinary Research Communications - Accurate estimation of a horse's age based on the condition of the tooth status is necessary as a scientific and artistic technique, which has not been... 相似文献
10.
Five morphinoid alkaloids have been isolated from Dehaasia longipedicellata, namely (-) pallidine, a new alkaloid (+) pallidinine (1), (+)-milonine, (-) 8,14-dehydrosalutaridine and (-) sinoacutine. 相似文献