Most cited article - PubMed ID 11347271
Vegetative survival, akinete formation and germination in three blue-green algae and one green alga in relation to light intensity, temperature, heat shock and UV exposure
This review surveys on the influence of different environmental factors like light (intensity, quality, photoperiod), temperature, season, nutrients (inorganic, organic), biotic factors (algal extracellular products, bacterial association, animals grazing), osmotic stress, pH of the medium, wave motion and mechanical shock, pollution, and radiations (UV, X-rays, gamma radiation) on the induction (or inhibition) of algal reproduction like cell division in unicellular algae, and formation of zoospores, aplanospores, akinetes, cysts, antheridia, oogonia, zygospores, etc.
- MeSH
- Ecosystem * MeSH
- Eukaryota growth & development physiology MeSH
- Plant Physiological Phenomena * MeSH
- Reproduction * MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
This review surveys whatever little is known on the influence of different environmental factors like light, temperature, nutrients, chemicals (such as plant hormones, vitamins, etc.), pH of the medium, biotic factors (such as algal extracellular substances, algal concentration, bacterial extracellular products, animal grazing and animal extracellular products), water movement, water stress, antibiotics, UV light, X-rays, gamma-rays, and pollution on the spore germination in algae. The work done on the dormancy of algal spores and on the role of vegetative cells in tolerating environmental stress is also incorporated.
- MeSH
- Ecosystem * MeSH
- Eukaryota physiology radiation effects MeSH
- Spores physiology radiation effects MeSH
- Cell Survival MeSH
- Publication type
- Journal Article MeSH
- Review MeSH
Pithophora oedogonia and Cladophora glomerata survived lowest 60 and 58%, respectively, in June when the pond diurnal water temperature (PDWT) increased to a maximum of 28 degrees C. The lowering of PDWT only by 1 degrees C in July improved survivability of both algae to their almost maximum level of 100 and 96%, respectively. Further lowering of PDWT to 17-22 degrees C in November initiated akinete formation in P. oedogonia. The process of akinete initiation, maturation and germination continued till April when PDWT increased to 20-24 degrees C, but not beyond that in May when PDWT was 21-26 degrees C. By this time, probably all akinetes have germinated in situ, and the alga was entirely vegetative. P. oedogonia population is not synchronous in nature, since during the 5-6-month reproductive season, some filaments were in active vegetative stage, some had akinete initiation, some had completed akinete formation, and some had akinetes germinating. C. glomerata grew dense vegetative in November and initiated (zoo)sporangial primordia formation (to some extent) in February (when PDWT was lowest, viz. 10-14 degrees C) till April. Meanwhile, no (zoo)-sporangial primordia either produced any zoospore or germinated into a germ tube; and all released their cytoplasmic content and died (along with some vegetative cells) with an increase in PDWT to 21-26 degrees C in May. Vaucheria geminata vegetative patches appeared on the soil surface, 2nd week of January by lowering of atmospheric diurnal temperature (ADT) to 9-16 degrees C in the 1st week. The alga started sexual reproduction by the 2nd week of March (when ADT increased to 20-23 degrees C) and completed the process of reproduction by the 1st week of April (when ADT increased to 24-26 degrees C) and died thereafter. P. oedogonia, C. glomerata and V. geminata survived better and longer in submerged conditions than air-exposed (which was true for P. oedogonia and C. glomerata aquatic habitat and also indicated that the soil alga V. geminata could survive to some extent if submerged in rain water). P. oedogonia formed akinetes and C. glomerata (zoo)sporangial primordia only in submerged condition and not when air-exposed on moist soil surface. V. geminata did not complete the life cycle both under submerged and air-exposed conditions. Vegetative survival in P. oedogonia, C. glomerata, V. geminata, Aphanothece pallida, Gloeocapsa atrata, Scytonema millei, Myxosarcina burmensis, Phormidium bohneri, Oscillatoria animalis, O. subbrevis, Lyngbya birgei, L. major, Microcoleus chthonoplastes and Rhizoclonium crassipellitum, reproduction in P. oedogonia, C. glomerata and V. geminata, cell division in A. pallida and G. atrata, heterocyst and false branch formation in S. millei, all, were adversely affected at approximately 28.5 degrees C for t12 h at light intensity of approximately 160 micromol m(-2) s(-1); high intensity does not ameliorate high temperature damage to any algae. The presence of liquid water, than its absence, outside the different algae moderated the severity of heat to some extent but not when the heat was severe.
Urea at 200 ppm (probably serving as a nitrogen source), liquid Bold's basal medium at pH 7.5, temperature of about 22 degrees C and light intensity of about 40 micromol m(-2) s(-1) for 16 h a day induced rapid and/or abundant zoospores formation and zoosporangia dehiscence and favored zoospore liberation, speed and motility time period in the green alga Rhizoclonium hieroglyphicum. However, factors such as water stress (2 and 4 % agarized media, liquid media with 0.2-0.4 mol/L NaCl, 5-60 min blot-dryness of filaments), pH extremes of liquid media (at < or =6.5 and > or =9.5), temperature shock in liquid media (5 and 35 degrees C for > or =5 min), UV exposure (0.96-3.84 kJ/m2), lack of all nutrients from liquid medium (double distilled water), darkness, and presence of "heavy" metals (1-25 ppm Cu, Fe, Zn, Hg, Ni, Co) or organic substances (200-600 ppm captan or DDT, 800 and 1000 ppm 2,4-D, 50 and 400 ppm indole-3-acetic acid (3-IAA), 1000 and 2000 ppm urea, 100 and 200 ppm thiourea) in liquid media decreased and/or delayed at various levels either zoosporangia survival, zoospore formation or zoosporangia dehiscence and/or the rate of zoospore liberation from zoosporangia, zoospore speed and time period of motility in the media or totally inhibited all these processes. 3-IAA at 50 and 400 ppm induced zoosporangial papilla to grow into a tube-like projection of about 30-120 microm in length. Zoosporangial dehiscence rather than zoospore formation or zoosporangia survival, and zoospore motility period rather than zoospore speed are probably more sensitive to various adverse environmental factors. The rate of zoospores liberation from zoosporangium (possibly related directly to some extent on the zoospore number inside) is probably independent of zoospore speed in the medium.
- MeSH
- Chlorophyta drug effects growth & development physiology radiation effects MeSH
- Hydrogen-Ion Concentration MeSH
- Culture Media MeSH
- Urea pharmacology MeSH
- Movement MeSH
- Spores drug effects growth & development radiation effects MeSH
- Temperature MeSH
- Metals, Heavy pharmacology MeSH
- Darkness MeSH
- Ultraviolet Rays MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Culture Media MeSH
- Urea MeSH
- Metals, Heavy MeSH
Morphological characteristics of an edible terrestrial cyanobacterium Nostoc flagelliforme in liquid suspension cultures under photoautotrophic conditions are presented. Different cell forms alternated in a regular manner during the experimentation period (30 d). N. flagelliforme exhibited a very complex life cycle in terms of colony morphology, including mainly 4 different colony morphological forms, viz. hormogonia, filaments, seriate colonies and aseriate colonies. Under laboratory conditions it formed spherical colonies on solid media but not threadlike colonies as it did under natural conditions. The overall life span of the alga was not altered by the existence of different nitrogen sources in the media despite the depression of some cell forms or colony morphologies. Compared with growth on the medium with urea and ammonium as nitrogen sources, the alga on standard medium had a short period of hormogonia and aseriate colony, suggesting that both ammonium and urea could stimulate the formation of hormogonia, at the same time inhibiting the formation of heterocystous cells. The new information on the growth and morphology of N. flagelliforme could be potentially used for the scale-up or field cultivation.
- MeSH
- Agar MeSH
- Culture Media MeSH
- Quaternary Ammonium Compounds metabolism MeSH
- Microbiological Techniques MeSH
- Urea metabolism MeSH
- Food Microbiology * MeSH
- Cyanobacteria cytology growth & development metabolism MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Agar MeSH
- Culture Media MeSH
- Quaternary Ammonium Compounds MeSH
- Urea MeSH
Vegetative cells in dried, mucilagenous mass of Gloeocapsa aeruginosa and Aphanothece nidulans, reticulum of Hydrodictyon reticulatum, mucilagenous mass of Chroococcus minor, and filaments of Oedogonium sp. and Scytonema hofmanni died within 1/2, 1/2, 1/2, 1, 3 and 6 h, respectively, while dried vegetative filaments of Phormidium foveolarum retained under similar storage conditions viability for 4 d. P. foveolarum tolerated 1 mol/L NaCl. The resistance to desiccation in P. foveolarum exhibited similar dependence as that to heat or UV light. The water stress imposed on growing algae either on high-agar solid media or in NaCl-containing liquid media reduced at various levels or altogether inhibited the survival of vegetative parts in all, the cell division in C. minor, G. aeruginosa and A. nidulans, formation of heterocyst and false branch in S. hofmanni, oogonium in Oedogonium sp., and daughter net in H. reticulatum. Heat or UV shock of any level also produced similar effects as that by water stress. P. foveolarum tolerated low light level of 10 and 2 mumol m-2 s-1 and no light longer than the rest of other algae studied. Tolerance of microalgal forms to water, heat or UV stress depends primarily upon cell-wall characteristics or cell-sap osmotic properties rather than their habitats, morphology and prokaryotic or eukaryotic nature.
Hydroxy, n-saturated, branched, dioic, and unsaturated fatty acids in six freshwater wild cyanobacteria (Chroococcus minutus, Lyngbya ceylanica, Merismopedia glauca, Nodularia sphaerocarpa, Nostoc linckia, and Synechococcus aeruginosus) collected from different lakes and springs of Israel have been identified by gas chromatography-mass spectrometry (GC-MS).
- MeSH
- Fatty Acids analysis MeSH
- Gas Chromatography-Mass Spectrometry MeSH
- Cyanobacteria chemistry classification isolation & purification ultrastructure MeSH
- Fresh Water microbiology MeSH
- Bacterial Typing Techniques MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Israel MeSH
- Names of Substances
- Fatty Acids MeSH
Dried vegetative filaments of Spirogyra sp., Vaucheria geminata and Nostoc calcicola died within 1/2, 1 and 4 h, respectively; those of Hormidium fluitans, Oscillatoria agardhii and Lyngbya martensiana retained under similar storage conditions viability for 3, 5 and 10 d, respectively. The viability of dried vegetative filaments of L. martensiana, O. agardhii and H. fluitans decreased on storage at 20 degrees C in the dark. L. martensiana and O. agardhii tolerated 0.8 mol/L NaCl. The resistance to desiccation in L. martensiana and O. agardhii exhibited similar dependence as that to frost, to heat and UV light. O. agardhii filaments became slightly broader and their cells developed large number of gas vacuoles when grown in 0.8 mol/L NaCl-containing medium. The water stress imposed on growing algae either on high-agar solid media or in NaCl-containing liquid media reduced hormogonium formation in L. martensiana and O. agardhii, heterocyst and akinete formation in N. calcicola and fragmentation in H. fluitans; it did not induce conjugation in Spirogyra sp. and formation of reproductive organs in V. geminata. In all studied algae the stress reduced at various levels the survival of vegetative parts. Generally, algal body form and composition rather than habitats seem to decide primarily the level of resistance against various stress conditions.
- MeSH
- Sodium Chloride pharmacology MeSH
- Culture Media MeSH
- Heat-Shock Response * MeSH
- Reproduction physiology MeSH
- Cyanobacteria growth & development physiology MeSH
- Ultraviolet Rays MeSH
- Hot Temperature MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Sodium Chloride MeSH
- Culture Media MeSH
Lack of nitrogen, phosphorus, or all nutrients, extremes of pH (< 4, > 11), presence of 'heavy' metals (Co, Cu, Zn, Hg, Pb; 0.5-10 ppm) or pesticides (carbofuran, 2,4-D, dithane, phorate, or bavistin; 1-50 ppm) decreased to various extent or completely inhibited the survival or vegetative cells in all studied algae. The formation of akinetes, their viability and germination in Anabaena iyengarii, Westiellopsis prolifica, Nostochopsis lobatus and Pithophora oedogonia and the formation of zoosporangia, their viability, and the germination of zoospores in Cladophora glomerata and Rhizoclonium hieroglyphicum was affected. The formation of viable akinetes or zoosporangia was shown to be directly linked with vegetative cell survival and growth; it could not be induced by any chemical stress imposed.
- MeSH
- Chlorophyta drug effects growth & development MeSH
- Nitrogen pharmacology MeSH
- Phosphorus pharmacology MeSH
- Hydrogen-Ion Concentration MeSH
- Culture Media MeSH
- Pesticides pharmacology MeSH
- Heat-Shock Response MeSH
- Cyanobacteria drug effects growth & development physiology MeSH
- Spores MeSH
- Metals, Heavy pharmacology MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Nitrogen MeSH
- Phosphorus MeSH
- Culture Media MeSH
- Pesticides MeSH
- Metals, Heavy MeSH
The influence of pH 3-10 on the growth, motility and photosynthesis in Euglena gracilis was demonstrated during a 7-d cultivation. The cells did not survive at pH < 4 and > 8, highest growth rate being detected at pH 7. Motility followed a similar pattern as growth rate. Photosynthetic response curves were shown to be of the same type over the whole pH range. High respiration was characteristic for cells grown at pH 5 and 6, the lowest one at 7. At high and also at low pH more active respiration was found which can be considered as a protective response on proton stress. Respiration was not completely inhibited with potassium cyanide. Photosynthesis was the most effective at pH 6; lower and higher pH decreased photosynthetic efficiency. pH affected more the growth rate than the photosynthesis.
- MeSH
- Euglena gracilis growth & development physiology MeSH
- Photosynthesis * MeSH
- Hydrogen-Ion Concentration MeSH
- Potassium Cyanide MeSH
- Movement MeSH
- Oxygen Consumption MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- Potassium Cyanide MeSH
