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Three species of blind Amphipoda are recorded from anchihaline cave waters in the Galapagos Islands. One of these, Galapsiellus leleuporum (Monod, 1970) was previously know from the islands; the male is described for the first time. The other two belong to families with predominantly (though not exclusively) deep-sea members: Valettietta cavernicola sp. nov. (family Lysianassidae; and Antronicippe serrata gen. et sp. nov. (family Pardaliscidae). The genus Valettietta was not previously recorded from caves; it contained two abyssal species in the Atlantic, while a third species was recorded from the Pacific in a vertical haul between 0 and 5300 m. Antronicippe is closely related to Spelaeonicippe, a genus with two species known from anchihaline caves in the Canary Islands and the West Indies. 相似文献
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In a study of tempe made by fermenting quinoa (Chenopodium quinoa Willd.) with Rhizopus oligosporus Saito, the interaction between the substrate and the fungus varied according to the raw material used. Low-temperature scanning electron microscopy confirmed that hyphal infiltration in quinoa was normally limited by the seed coat, but a massive penetration was found in fragments of quinoa where the testa was broken. This finding has implications for the texture and quality of tempe fermentation of grains and pulses. 相似文献
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Wheat, Triticwn aestivum L., the winter cultivars Hobbit andCappelle-Desprez, and the spring cultivars Sicco and KJeiber,were grown in normal air or air enriched with CO2 either outdoorsin a glass-roofed cage or in controlled environment rooms. Inneither the winter nor the spring wheat was growth increaseddue to enrichment with CO2 before anthesis. Enrichment of thetwo winter wheat cultivars increased shoot dry weight significantlyat 15 d after anthesis but produced no significant increasein grain yield. With the spring cultivars there was a significantincrease in shoot dry weight by 18 d after anthesis and thegrain yield was also larger due to an increase in grain size.Shoot weight increased because the stems were larger, and therewas a diversion of assimilate from grain growth to late tillerproduction. Root tissue comprised less than 20% of the totaldry matter at anthesis (for all cultivars); effects of CO2 enrichmenton root growth appeared to be less important than effects onshoot and ear growth. Growth and yield responses to CO2 enrichmentwere observed (for the spring cultivars) at irradiances of both250 and 635 µE m2 s1, but the effects weregreater at the lower irradiance. Key words: CO2 enrichment, Wheat, Cultivar 相似文献
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The photosynthetic uptake of root-zone CO2 was determined forEriocaulon septangulare, Gratiola aurea, Isoetes macrospora,Littorella uniflora var. americana and Lobelia dortmanna aspart of a study of the photosynthetic carbon economy of submergedaquatic isoetids. The pH and dissolved inorganic carbon (DIC)of the sediment interstitial water in four Wisconsin lakes reflectedthe water column character, where the DIC increased with depthin the sediment to concentrations five to ten times those ofthe water column. Sediment free CO2 concentrations were 550times those in the water column and were similar at all sites(about 051.0mM CO2 in the root-zone). In pH-driftstudies these plants were unable to take up HCO2. Laboratory determinations of the carbon uptake from the rootand shoot-zones were made for all five species. These experimentsshowed that CO2 in the root-zone accounted for 6595 percent of external carbon uptake for the five species. For G.aurea and E. septangulare, root-zone CO2 was > 85 per centof carbon uptake. Carbon, CO2, photosynthesis, sediment, isoetid, Eriocaulon septangulare, Gratiola aurea, Isoetes macrospora, Littorella uniflora, Lobelia dortmanna 相似文献