Ecotypes

Bjorkman, O. Holmgren, P. (1963). Adaptability of the photosynthetic apparatus to light intensity in ecotypes from exposed and shaded habitats. Physiologia Plantarum, 16, 889-914. 

Gauhl, E. (1976). Photosynthetic response to varying light intensity in ecotypes of Solanum dulcamara L. from shaded and exposed habitats. Oecologia, 22,275-86. 

Insectivora (4/6) Poorly studied but comparable to other primitive eutherians (Broom, 1915 Hofer, 1982 Stephan, 1982 Matsuzaki et al., 1993) the variety of ecotypes represented, from aquatic to burrowing, are unknown for chemoreceptive adaptations. 

Zearalenone (mycotoxin) scFv Passive immunization of animals in their feed A. thaliana (ecotype Columbia) Inducible lac No targeting signal - 58... 

Scalfi L, Fogliano V, Pentangelo A, Graziani G, Giordano I and Ritieni A. 2000. Antioxidant activity and general fruit characteristics in different ecotypes of Corbarini small tomatoes. J Agric Food Chem 48(4) 1363-1366. 

The basic approach used by Roessner et a/.39,41 has also been developed by Fiehn et al. for Arabidopsis. 43 Using GC-MS analysis, these authors distinguished some 326 distinct compounds in Arabidopsis leaves, of which roughly half could be assigned a chemical structure. They applied the GC-MS method to the analysis of four different Arabidopsis genotypes the ecotype Columbia (Col-2) and the dgdl... 

Smith MM, Hodson MJ, Opik H, Wainwright SJ. Salt-inducedultrastructural damage to mitochondria in root tips of a salt-sensitive ecotype of Agrostis stolonifera. J Exp Bot 1982 33 886-895. 

Fig. 9.6 Chemical structures of phytoalexins from Thellungiella salsuginea Shandong ecotype 1-methoxybrassenin B (15), rapalexin A (16), wasalexins A (17) and B (18), biswasalexins A1 (19), and A2 (20)...

Fig. 9.8 Proposed biosynthetic pathway of phytoanticipins 21 and 29 and phytoalexins 17/18 and 28 in Thellungiella salsuginea Shandong ecotype (two arrows indicate more than one intermediate in the pathway)...

Differences in lignification of forage crops were examined in terms of genetic, biosynthetic and environmental factors. This was achieved by comparison of brittle ecotypes of fescue (Festuca arundinacea), and brown-midrib (b.m.3)-mutants of maize (Zea mays) with the corresponding normal plants. For each plant type,... 

Firstly, we studied possible relationships between lignin variation and brittleness of plant organs, using two ecotypes of tall fescue grass (Festuca arundinacea Schreb). Thus, both normal fescue and a brittle ecotype (discovered by Jadas-Hecart (27)), characterized by a brittleness of leaves, sheath and stem, were compared. Possible environmental effects on the biochemistry of lignin formation were estimated by comparison of several parallel crops from two locations. 

Table I. Klason, Acid-insoluble, and Acetylbromide Lignin Contents of Normal and Brittle Fescue Ecotypes Grown at Grignon and Lusignan (standard deviation less than 10%)...

In both localities, the strains were sorted according to their similarities and clustered using the KHI2 coefficient and variance analysis. On the graphical representation of this sorting (dendrograms), any group or isolate at a level of 70 % (90% for the api 20 B tests) of similarity was considered as a different bacterial ecotype. 

Various mechanisms of tolerance have been proposed to explain how some plants cope with toxic conditions and how some species have developed tolerant ecotypes (Baker, 1989 Cumming and Tomsett, 1992 McNair and Baker in Chapter 3)... 

Lead is considered to be a non-essential metal to plants, and only a small proportion of the lead in soils is biovailable to plants (Alloway, 1990). Visible symptoms of toxicity, though unspecific to Pb, are smaller leaves and a stunted growth. Leaves may become chlorotic and reddish with necrosis and the roots may turn black. Several plant species, ecotypes and bacterial strains have been known to develop Pb tolerance. The phytotoxicity of Pb is low as it has very limited availability and uptake from soil and soil solutions. However, plant roots are usually able to take up and accumulate large quantities of Pb2+ in soil and culture solutions but translocation to aerial shoots is generally limited due to binding at root surfaces and cell walls (Lagerwerff, 1971 Jones et al., 1973 Lane and Martin, 1977). 

The evolution of the tolerant ecotype is conceptually easy. As described above, first tolerance evolves, and then further adaptations to the other features of the mine environment can be expected to spread. Other genes that enhance the tolerance produced by the initial gene(s) (modifiers) increase the adaptation (Macnair, 1983 Schat and ten Bookum, 1992 a). The problem is, how does an ecotype evolve into a full species Kruckeberg (1984) points out that on the California serpentines there are about 250 endemic taxa, but a further 1000 species that are found both on and off the serpentine (bodenvag species), most of which can be expected to have evolved serpentine-tolerant taxa. What is the difference between a bodenvag species and a species that has evolved into an edaphic endemic ... 

---