A high-affinity K+ transporter PutHKT2;1 cDNA was isolated from the salt-tolerant plant Puccinellia tenuiflora. Expression of PutHKT2;1 was induced by both 300 mM NaCl and K+-starvation stress in roots, but only slightly regulated by those stresses in shoots. PutHKT2;1 transcript levels in 300 mM NaCl were doubled by the depletion of potassium. Yeast transformed with PutHKT2;1, like those trans...

BACKGROUND AND AIMS Most studies on seed position-dependent effects have focused on germination characteristics. Our aim was to determine the effects of seed position in the spikelet on differences in timing of germination and on the ecological life history of the grass Eremopyrum distans in its cold desert habitat. METHODS For seeds in three spikelet positions, morphology, mass and dormancy/...

This paper is the first taxonomic account of the hydroid orders Anthoathecatae and Leptothecatae from the Caribbean and Pacific coast of Costa Rica. All specimens are currently stored at the reference collection of the Museo de Zoología, Escuela de Biología, Universidad de Costa Rica. Sixteen hydroid species are recorded: Eudendrium carneum, Pennaria disticha, Acryptolaria longitheca, Plumulari...

The Wolf–Rayet phenomenon is a stellar phenomenon. This means that its length scale is essentially that of the star, i.e. some 10 cm. A typical nebular size is 10 cm or higher, which immediately illustrates that it may not be easy to make the connection between the star and the nebulae and observations confirm this. In this paper I will try to discuss some ways in which the nebular properties c...

Soil salt-alkalinization is a widespread environmental stress that limits crop growth and agricultural productivity. The influence of soil alkalization caused by Na(2)CO(3) on plants is more severe than that of soil salinization. Plants have evolved some unique mechanisms to cope with alkali stress; however, the plant alkaline-responsive signaling and molecular pathways are still unknown. In th...