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991.
Ernesto P. Benito Arjen ten Have John W. van 't Klooster Jan A.L. van Kan 《European journal of plant pathology / European Foundation for Plant Pathology》1998,104(2):207-220
An inoculation procedure was developed to obtain efficient and synchronous infection on detached tomato leaves by Botrytis cinerea. In spray-inoculated leaves incubated at 20 °C, the infection process consisted of three phases: the formation of primary necrotic lesions (until 20 hpi), a quiescent phase (20-72 hpi), and the expansion of a proportion of the primary lesions (from 72 hpi onwards), resulting in full tissue maceration. At 4 °C, the infection progressed slowly but steadily without inducing necrotic responses in the host. The actin and -tubulin genes of B. cinerea were cloned, characterized and used as probes on blots containing RNAs from leaves at various stages of the infection. The genes displayed a similar expression pattern throughout the infection and the hybridization signal reflected the amount of fungal biomass. The actin mRNA accumulated to higher levels than the -tubulin mRNA. Tomato PR protein mRNAs (chitinase, -1,3-glucanase and PR-1) were induced during the infection, albeit with different kinetics and to different levels. At 20 °C, -1,3-glucanase and PR-1 mRNAs were induced more rapidly than chitinase mRNAs. At 4 °C, mRNAs encoding extracellular -1,3-glucanase and intracellular, as well as extracellular chitinase were hardly induced. 相似文献
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研究了同步叶片修剪对温室番茄品种‘Capita’干物质优化分配的影响。结果表明, 在每穗果实数修剪为6个时, 一方面会减少营养生长库强, 显著降低了叶面积指数(LA I) 和植株总干质量; 另一方面有利于干物质分配到果实, 显著提高果实累积干物质分配率, 补偿因植株总干质量降低而引起的果实干质量的降低。在合理增加植株密度时, 同步叶片修剪可以显著提高LA I与单位面积植株总干质量, 从而显著提高单位面积果实干质量。 相似文献
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In nature, oviposition and larval growth of the olive fruit flyBactrocera oleae (Rossi) (Diptera: Tephritidae) occur only in the mesocarp of fruits of the genusOlea, including the cultivated olive. Here we report on its growth in tomatoes, in the laboratory, as affected by a number of
factors. Caged flies from a colony reared for more than 100 generations on an artificial diet, oviposited in intact fruits
of four tomato cultivars in an unheated greenhouse and in the open. In choice tests, at 25°C, 16L:8D and 65% r.h., medium
(5–6 cm diam) and large (>6 cm diam) fruits received more eggs than small (3–4 cm diam) fruits, but differences were not significant
in all cases. In all cultivars, more eggs were laid in greenhouse than in open-air tomatoes of three different degrees of
maturity, the differences being significant in most cases. The smaller the resistance of a cultivar’s epicarp to penetration
by flat ended 0.2 and 1 mm square probes, the greater the number of eggs a cultivar received. Green (unripe) fruits proved
unsuitable for larval growth. Half-ripe and fully ripe (red) fruits of cvs. ‘Isidro’, ‘204’, ‘Tobo’ and ‘Ace’ yielded pupae
of acceptable weight (mean 5.6 to 6.7 mg) with a high percentage of adult emergence, yet the yield was considerably lower
than that of olive fruit. Fully ripe greenhouse Isidro tomatoes yielded an average of 3.2 adults per fruit and 20.4% of the
eggs laid developed into adults, whereas the other categories and cultivars yielded less. The mean percentages of pupae over
eggs were higher in fully ripe Isidro and 204 fruits, than in half-ripe Tobo and Ace ones. The mean time from oviposition
to pupation ranged from 16.2 to 25 days, depending on the cultivar and degree of fruit maturity. In fully ripe Isidro and
204 fruits, the fewer the eggs laid per fruit, the higher the percent yield in pupae and the longer the time from oviposition
to pupation. Greenhouse fully ripe fruits of cv. 204 maintained under a low light intensity of 50 lux gave a much lower yield
in pupae and slower larval growth than under 1600 lux. The usefulness of tomatoes as substitutes of artificial diets in rearing
the fly is discussed.
http://www.phytoparasitica.org posting May 20, 2005. 相似文献
997.
Sopid Sawangjit Orawan Chatchawankanphanich Pissawan Chiemsombat Tipvadee Attathom James Dale Supat Attathom 《Journal of General Plant Pathology》2005,71(4):314-318
Nucleotide sequences of the three distinct Tomato yellow leaf curl Thailand virus (TYLCTHV) strains (CM, NK, SK) were analyzed for recombination events. Recombination detection program analyses and a sequence alignment survey provided evidence of recombination between AC1 sequences of TYLCV, TYLCTHV-[MM], and TYLCTHV-[NK] as major parents and of ToLCLV, ToLCTWV, and TYLCTHV-[SK] as minor parents of TYLCTHV-[NK], -[SK], -[CM], respectively. The results further support the notion that interspecies recombination may play a significant role in geminivirus diversity and their emergence as important pathogens. 相似文献
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