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131.
Zygophyllum simplexL. is a succulent annual that grows on thecoastal and inland saline flats around Karachi, Pakistan. Theseeds are moderately salt tolerant during germination. GerminationofZygophyllum simplexseeds under various salinity, proline,betaine, GA and kinetin treatments was determined. Proline (0.1and 1 mM) and betaine (0.1 and 1 mM) alleviated the innate dormancyof seeds, and germination reached 60–70% compared to 12%in the control set. At low salinity compatible osmotica alleviatedsome effects of salinity, but at higher NaCl concentrationsboth proline and betaine were ineffective. Gibberellic acid(0.3 and 3 mM) and kinetin (0.05 and 0.5 mM) substantially alleviatedboth innate as well as salinity-induced seed dormancy. At highersalinity (125 mM), low concentrations of kinetin (0.05 mM) andhigh concentrations of GA (3 mM) were more effective. GA completelyalleviated the effect of salinity at all concentrations used. Betaine; desert; dormancy; forb; GA; germination; halophyte; kinetin; proline; seeds; Zygophyllum simplex  相似文献   
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KHAN  S. R. 《Annals of botany》1976,40(6):1285-1292
Maturation of sporangia in Albugo sp. involved considerableinternal differentiation. There was a burst of activity in sporangiasoon after their formation when the numbers of mitochondria,and the amounts of endoplasmic reticulum increased. Perinuclearvesicles and smooth surfaced cisternae differentiated into well-developedgolgi apparatus which remained secretory until completion ofmaturation. The cisternae of rough endoplasmic reticulum arrangedthemselves in parallel stacked arrays. Maturing sporangia hadautophagic vacuoles containing various cell organelles. Nucleardegeneration and mitosis proceeded simultaneously. All activitiesdeclined towards the end of sporangial maturation: Golgi dictyosomesbecame quiescent and numbers of mitochondria and amounts ofendoplasmic reticulum decreased. There was a three-fold increasein the thickness of the sporangial wall during maturation.  相似文献   
134.
The effect and involvement of ethylene in germination of partially after-ripened apple (Malus domestica Borkh. cv. Antonovka) embryos were studied. The requirement of ethylene for germination was shown by the use of a rhizobitoxine analog and 8-hydroxy-quinoline sulphate which are inhibitors of ethylene biosynthesis, and by mercuric perchlorate, a trap for endogenously produced ethylene. Excised apple embryos were found to produce progressively greater amounts of ethylene with increasing periods of after-ripening. Inhibition of germination by rhizobitoxine analog or abscisic acid was accompanied by inhibition of ethylene formation in embryos. Thus ethylene appears to be required for the release of dormancy and germination of apple embryos.  相似文献   
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On seven occasions measured amounts of 14CO2 were supplied toindividual leaves on tomato plants grown as a crop under commercialconditions. Twenty-four hours later the distribution of radiocarbonproducts was determined using counting procedures. In the vegetativephase lower leaves exported more carbon up than down, and upperleaves a larger proportion downwards. During the developmentof the crop upper leaves continued to export more carbon downthan up, and lower leaves developed a similar tendency. In theyoung fruiting crop all leaves supplied all the trusses, butas the number of trusses increased groups of leaves came tohave primary (but not absolute) responsibility for supplyingsingle trusses. At the time of fruit development the leavesretained for 20–24 hours more than 80 per cent of thecarbon they fixed. Mature leaves and stems both above and belowthe test leaves were significant sinks for 14C products.  相似文献   
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