Flower opening and closure: a review
نویسندگان
چکیده
Flower opening and closure are traits of a reproductive syndrome, as it allows pollen removal and/or pollination. Various types of opening can be distinguished such as nocturnal and diurnal and single or repetitive. Opening is generally due to cell expansion. Osmotic solute levels increase by the conversion of polysaccharides (starch or fructan) to monosaccharides, and/or the uptake of sugars from the apoplast. Repeated opening and closure movements are often brought about by differential elongation. In tulip petals, for example, the upper and lower sides of the mesophyll exhibit a 10 °C difference in optimum temperature for elongation growth, resulting in opening in the morning and closure in the evening. Opening and closure in several other species is regulated by changes in light intensity and, in some species with nocturnal opening, by an increase in relative humidity. A minimum duration of darkness and light are usually required for opening and closure, respectively, in ̄owers that open during the day. Both phytochrome and a blue light receptor seem involved in light perception. In some species, opening and closure are regulated by an endogenous rhythm, which, in all cases investigated, can be reset by changes from dark to light and/or light to dark. So far, Arabidopsis mutants have not been used to investigate the timing of ̄ower opening and closure. As its ̄owers open and close in a circadian fashion, several mutants that are involved in the circadian clock and its light input may help to provide an insight into this type of ̄ower opening. The co-ordination of processes culminating in synchronized ̄ower opening is, in many species, highly intricate. The complex control by endogenous and exogenous factors sets ̄ower opening and closure apart from most other
منابع مشابه
Flower opening and closure: a review.
Flower opening and closure are traits of a reproductive syndrome, as it allows pollen removal and/or pollination. Various types of opening can be distinguished such as nocturnal and diurnal and single or repetitive. Opening is generally due to cell expansion. Osmotic solute levels increase by the conversion of polysaccharides (starch or fructan) to monosaccharides, and/or the uptake of sugars f...
متن کاملبررسی نتایج عمل جراحی یکصد مورد کیست هیداتید ریه به روش (E.B.O.C (Evacuation and Bronchial Opening Closure
متن کامل
Expression of Genes Encoding Protein Kinases During Flower Opening in Two Cut Rose Cultivars with Different Longevity
Ethylene plays an important role in wide-ranging aspects of plant growth and development, includingfruit ripening, leaf and flower senescence. In this study, the expression patterns of two genes involved in theethylene signal transduction pathway (RhCTR1 and RhCTR2) were investigated during the flower openingstages in two Rosa hybrida cultivars, ‘Black magic’ and ‘Maroussia’, ...
متن کاملLaparoscopic Cholecystectomy; closure versus non-closure of the fascial sheath opening of the sub-umbilical port site “10 mm”.
Background: Laparoscopic Surgery (LS) may be associated with many port site complications such as hernia, bleeding, infection, subcutaneous emphysema and ugly scars. Some of these complications are serious such as obstructed port site hernia . Rate of these complications is low depending on size and site of the port incision, type of the trocar that it is used, the condition of the patient a...
متن کاملCold work simulation of hole expansion process and its effect on crack closure
Using cold working fastener holes is a simple life enhancement procedure that strengthens metallic components by retarding crack growth around a hole. In the present paper, the residual stress field that is induced by the hole expansion process is obtained based on different material models namely elastic perfect plastic, isotropic hardening and kinematic hardening using three-dimensional finit...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2003