Hormonal regulation of rest, ageing and stress. The summary

you are: Hormonal regulation of rest, ageing and stress

Maturing of fruits and other aspects of development and ageing in plants are regulated by formation of a gaseous hormone - etilena. That fact that etilena it is possible to eliminate action, having raised concentration СО2 in environment, underlies practical reception of storage of apples and other fruits at high concentration СО2. Etilen are caused by formation apikalnogo a bend in many etiolirovannyh sprouts, and influence of light on bend straightening is connected by that it ingibiruet formation etilena. Etilen can influence also on geotropizm and others mediated auksinom reactions, such, as suppression of growth of lateral kidneys. Interaction auksina and etilena is carried out by different ways as high level auksina starts formation etilena whereas high level etilena can induce enzyme synthesis peroksidazy, inaktivirujushchego IUK. Etilen it is formed from 1-aminotsiklopropan-1-karbonovoj acids (ATSK), metabolita methionine. Earlier the maintenance etilena defined exclusively by means of biotests. Now as a routine method of its definition the gas chromatography serves.

Processing etilenom unripe fruits in many cases leads to substantial growth of quantity СО2, allocated at breath. Such sharp lifting of breath is called klimakteriem. After this change the maintenance of organic acids decreases, intercellular pectins collapse, and fruits ripen. Similarly processing etilenom leaves starts the whole series of the metabolic processes leading to subsidence of leaves. These processes include cell fission and the subsequent formation otdelitelnogo a layer of the thin-walled cages which destruction under the influence of neogenic tselljulazy causes sbrasyvanie leaves. length of day can regulate subsidence of leaves by initsiatsii ageing process in otdelitelnoj to a zone that should occur prior to the beginning of subsidence. In certain cases drawing of low concentration auksina on a sheet plate or a fruit detains ageing thanks to that auksin will neutralise action etilena. Such prevention of subsidence plays the important role at cultivation of fruits. High level auksina, on the contrary, can accelerate sbrasyvanie leaves, and such planned defoliatsija also has found certain practical application. At other types induced etilenom ageing stimulating hormones, including auksin, tsitokinin and gibberellin, can counteract influence etilena.

At revolution of the season in moderate zones before plants there are survival problems. Partially they solve them by transition in a condition of rest or an exit from it. So, reduction of length of day can induce formation of one of hormones abstsizovoj acids (ABK) which suppresses active vegetative growth of kidneys or developing germs and starts the processes conducting to winter rest. Renewal of growth, on the contrary, is caused in the spring by destruction within winter of this hormone inducing rest or synthesis of substances, such, as tsitokininy which overcome influence ABK. Such infringement of rest in kidneys is induced by low winter temperatures whereas blooming of kidneys occurs after rise in temperature and increase in length of day in the spring. Rest of seeds can be interrupted under the influence of water, light or low temperature. In many types of seeds some part mrnk, coding the fibers necessary at germination, is formed before indutsirovaniem rest. In dry seeds this mrnk remains stable and nonfunctioning in expectation of signals to germination.

In some leaves abstsizovaja acid is developed in high concentration at water stress. It causes outflow of ions To + from closing cages therefore ustitsa are closed and by that danger of drying is prevented. Action ABK and etilena, apparently, is caused partially by their influence on selective permeability of membranes, and partially - their participation in regulation of synthesis of fiber.