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G. Kritzman A. Shani-Cahani B. Kirshner Yehudit Riven Z. Bar J. Katan A. Grinstein 《Phytoparasitica》1996,24(4):293-304
Peanut pod wart, a relatively new disease to peanut culture, was first reported in Israel in 1988 attacking peanut plants and causing dark warts on the pod. The causal agents are variousStreptomyces spp. Scanning electron microscopy showed a significant difference between healthy and diseased tissues of the exocarp and mesocarp layers of the pod; there were no effects on the endocarp layer. The mesocarp cells of infected tissue were smaller and more compressed than those of healthy tissue. In most cases two cells under the peak of the wart were extremely large and the cells growing from them toward the surface were uneven, forming the shape of a fan. The pathogen could be isolated from the soil and rhizosphere, but in the pod it was found only in the waited tissue. The microorganisms isolated from the warts belong to different groups ofStreptomyces spp.; subsequent pathogenicity tests proved their virulence to a limited host range. In potato, these isolates ofStreptomyces spp. caused deep pitted scab; in peanuts they caused warts. Peanut seeds which developed in infected pods were free of the pathogen if the shell was undamaged. However, the pathogen is surface seedborne, and contaminated seeds during the mechanical cracking process. 相似文献
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Elisabeth J. Faassen Maria G. Antoniou Wendy Beekman-Lukassen Lucie Blahova Ekaterina Chernova Christophoros Christophoridis Audrey Combes Christine Edwards Jutta Fastner Joop Harmsen Anastasia Hiskia Leopold L. Ilag Triantafyllos Kaloudis Srdjan Lopicic Miquel Lürling Hanna Mazur-Marzec Jussi Meriluoto Cristina Porojan Yehudit Viner-Mozzini Nadezda Zguna 《Marine drugs》2016,14(3)
Exposure to β-N-methylamino-l-alanine (BMAA) might be linked to the incidence of amyotrophic lateral sclerosis, Alzheimer’s disease and Parkinson’s disease. Analytical chemistry plays a crucial role in determining human BMAA exposure and the associated health risk, but the performance of various analytical methods currently employed is rarely compared. A CYANOCOST initiated workshop was organized aimed at training scientists in BMAA analysis, creating mutual understanding and paving the way towards interlaboratory comparison exercises. During this workshop, we tested different methods (extraction followed by derivatization and liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) analysis, or directly followed by LC-MS/MS analysis) for trueness and intermediate precision. We adapted three workup methods for the underivatized analysis of animal, brain and cyanobacterial samples. Based on recovery of the internal standard D3BMAA, the underivatized methods were accurate (mean recovery 80%) and precise (mean relative standard deviation 10%), except for the cyanobacterium Leptolyngbya. However, total BMAA concentrations in the positive controls (cycad seeds) showed higher variation (relative standard deviation 21%–32%), implying that D3BMAA was not a good indicator for the release of BMAA from bound forms. Significant losses occurred during workup for the derivatized method, resulting in low recovery (<10%). Most BMAA was found in a trichloroacetic acid soluble, bound form and we recommend including this fraction during analysis. 相似文献
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The global trend to shift from highly toxic pesticides to environmentally safe and less toxic chemicals requires, generally, very high spatial uniformity of the spray deposition. Effective penetration of the spray into a dense canopy can be achieved by utilizing fast air-streams. In contrast, slow and turbulent flow near the leaves and the stems is required for good deposition of the spray. A new sprayer was designed to achieve a sharp decline in air velocity to meet the two — seemingly contradictory — constraints, and thereby obtain effective penetration and coverage of dense canopy. In the present work, air ducts with several shapes of air outlets were developed and tested in an attmept to meet these requirements. Generally, a short and wide air slit created a moderate decline in air velocity; a longer and narrower air slit improved the uniformity of the air velocity along the slit outlet, and brought about a sharper decline in speed of the air-streams. Installing air deflectors at the air outlets added a slight upward motion to the air-streams and enhanced spray deposition on the underside of leaves. Preliminary field tests with the long and narrow air slit showed uniform spray deposition on all plant parts. 相似文献
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Liat Avrahami-Moyal Yehudit Tam Marina Brumin Shanmugam Prakash Diana Leibman Malenia Pearlsman Menachem Bornstein Noa Sela Mouhammad Zeidan Zion Dar Uri Zig Amit Gal-On Victor Gaba 《Phytoparasitica》2017,45(4):591-598
Potato (Solanum tuberosum) is the largest crop in Israel. Production is based on the import of seed tubers from Europe for the spring crop. Imported tubers are generally free from virus infection. The most important virus infecting potato is Potato virus Y (PVY), which may cause severe damage to marketable yields. In Israel, tubers from the spring harvest are stored over the summer for planting in the autumn. It is important to be able to determine the infection rate of seed tuber lots from the spring harvest prior to storage. Commonly, infection is measured by sprouting tubers and measuring virus titre in the leaves using ELISA (the “Growing-On test”), which takes at least 6 weeks to give results. There is a need for a faster method to produce results, such as Taqman Real Time PCR (qPCR), for direct analysis of viral infection in tubers at harvest. To use qPCR as a diagnostic tool, it is necessary to demonstrate that both techniques give comparable results on batches of field-grown tubers. Such a comparison was performed on potential seed tuber lots of 14 different cultivars over three Israeli spring harvests (2013–2015). The agreement between the results of the two techniques was not of high statistical significance. However, the qPCR technique can distinguish well, by binary classification, between tuber lots with a low PVY infection rate (<5% by Growing On test; suitable for seed) and those unsuitable for seed (≥5% by Growing On test). Therefore, qPCR is an appropriate technique for determination of the PVY infection rate of seed tuber lots in Israel. 相似文献
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