Limiting similarity of competitive species and demographic stochasticity.

The limiting similarity of competitive species and its relationship with the competitive exclusion principle is still one of the most important concepts in ecology. In the 1970s, May [R. M.

The Class II KNOX gene KNAT7 negatively regulates secondary wall formation in Arabidopsis and is functionally conserved in Populus.

• The formation of secondary cell walls in cell types such as tracheary elements and fibers is a defining characteristic of vascular plants. The Arabidopsis transcription factor KNAT7 is a component of a transcription network that regulates secondary cell wall biosynthesis, but its function has remained unclear. • We conducted anatomical, biochemical and molecular phenotypic analyses of Arabidopsis knat7 loss-of-function alleles, KNAT7 over-expression lines and knat7 lines expressing poplar KNAT7.

[Effect of the combination of cadmium and UV-B radiation on soybean growth].

This paper studied the characteristics of soybean growth under the stress of Cd, UV-B radiation and their combination. The results showed that UV-B radiation gave a more pronounced inhibition on soybean growth than cadmium. Under UV-B radiation, the internode differentiation and elongation were inhibited, the internode and plant height were reduced, and the activities of SOD and POD had an apparent increase.