General mechanisms of drought response and their application in drought resistance improvement in plants

Plants often encounter unfavorable environmental conditions because of their sessile lifestyle. These adverse factors greatly affect the geographic distribution of plants, as well as their growth and productivity. Drought stress is one of the premier limitations to global agricultural production due to the complexity of the water-limiting environment and changing climate. Plants have evolved a series of mechanisms at the morphological, physiological, biochemical, cellular, and molecular levels to overcome water deficit or drought stress conditions. The drought resistance of plants can be divided into four basic types-drought avoidance, drought tolerance, drought escape, and drought recovery. Various drought-related traits, including root traits, leaf traits, osmotic adjustment capabilities, water potential, ABA content, and stability of the cell membrane, have been used as indicators to evaluate the drought resistance of plants. In the last decade, scientists have investigated the genetic and molecular mechanisms of drought resistance to enhance the drought resistance of various crops, and significant progress has been made with regard to drought avoidance and drought tolerance. With increasing knowledge to comprehensively decipher the complicated mechanisms of drought resistance in model plants, it still remains an enormous challenge to develop water-saving and drought-resistant crops to cope with the water shortage and increasing demand for food production in the future.     

The effect of abrin,anti-lymphocyte globulin and their conjugates on the immune response of mice to sheep red blood cells

Summary A chemical conjugate of anti-mouse lymphocyte globulin and abrin, is about twice as effective as a similar conjugate made with normal immunoglobulin and abrin, in suppressing the ability of the mouse to respond immunologically to an injection of sheep red blood cells.Acknowledgment. We thank Dr Stuart, Society of Herbalists, London, and Prof. G.C. Clark, Dept. of Botany, University of Ghana, for gifts ofAbrus precatorius seeds, and Mrs L. Bushby for help in the preparation of the horse anti-mouse lymphocyte globulin. D.C.E. is an external member of the staff of the Wellcome Foundation Ltd.