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21.
Malformin stimulated ethylene production of Phaseolus vulgarisL. seedlings and explants. However, when malformin was vacuum-infiltratedinto apical bud sections, the production of ethylene was inhibited,ethane production was stimulated and the sections became softand pliable; in pure oxygen, ethylene production was- stimulatedand the sections remained firm. Prolonged stimulation of ethaneproduction by malformin-treated sections required oxygen. Indoleaceticacid (IAA) had no effect on the stimulation of ethane productionby malformin-infiltrated tissues; malformin and IAA stimulatedethylene production synergistically at the same time that malformininducedethane production had increased markedly.
1This work was supported by grant GB-7158 from the NationalScience Foundation.
2Journal Paper No. 3560 of the Purdue Agricultural ExperimentStation. (Received July 23, 1969; ) 相似文献
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ROY AB 《The Biochemical journal》1956,62(1):41-50
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RACHAEL HICKLING † DAVID B. ROY JANE K. HILL† RICHARD FOX‡ CHRIS D. THOMAS† 《Global Change Biology》2006,12(3):450-455
Evidence is accumulating of shifts in species' distributions during recent climate warming. However, most of this information comes predominantly from studies of a relatively small selection of taxa (i.e., plants, birds and butterflies), which may not be representative of biodiversity as a whole. Using data from less well‐studied groups, we show that a wide variety of vertebrate and invertebrate species have moved northwards and uphill in Britain over approximately 25 years, mirroring, and in some cases exceeding, the responses of better‐known groups. 相似文献
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1. The interspecific relationship between the distributions of consumers and resources is examined, using data for macrolepidoptera (moths) in Britain.
2. Monophagous moth species feeding on host plants with small geographical ranges also have small ranges, whilst those feeding on host plants with large ranges may have small or large ranges themselves. Likewise, there is an approximately triangular relationship between the proportion of the range of its host that a monophagous moth occupies and the size of the host range.
3. Most monophagous moths occupy a small proportion of the range of their host, and only feed on hosts that have relatively large geographical ranges.
4. Factors determining both the range size of a monophage and the proportion of the host plant's range that it occupies are independent of taxonomy.
5. Monophages tend to have smaller geographical ranges than congeneric polyphages, but do not occupy a smaller proportion of the ranges of the plants that they consume. 相似文献
2. Monophagous moth species feeding on host plants with small geographical ranges also have small ranges, whilst those feeding on host plants with large ranges may have small or large ranges themselves. Likewise, there is an approximately triangular relationship between the proportion of the range of its host that a monophagous moth occupies and the size of the host range.
3. Most monophagous moths occupy a small proportion of the range of their host, and only feed on hosts that have relatively large geographical ranges.
4. Factors determining both the range size of a monophage and the proportion of the host plant's range that it occupies are independent of taxonomy.
5. Monophages tend to have smaller geographical ranges than congeneric polyphages, but do not occupy a smaller proportion of the ranges of the plants that they consume. 相似文献
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1. The mating system of Mediterranean fruit flies ( Ceratitis capitata , Diptera: Tephritidae), is based on male leks that form on the foliage of trees. Following observations that not all males participate in leks, the hypotheses that (a) small males are absent from leks and (b) males with inadequate nutrient reserves are unable to participate in leks were examined.
2. The size and weight of lekking males ( n = 183) and resting males captured at the same time in the vicinity of leks ( n = 148) were established. In addition, using biochemical techniques, the amounts of sugar, glycogen, lipid and protein in each individual were established quantitatively.
3. There was no significant size difference between lekking and resting males. However, lekking males were significantly heavier and contained significantly more sugars and protein than resting males.
4. In conclusion, leks are exclusive, and only males with adequate nutritional reserves may join. Thus, in this species, reproductive success is closely linked to foraging success. 相似文献
2. The size and weight of lekking males ( n = 183) and resting males captured at the same time in the vicinity of leks ( n = 148) were established. In addition, using biochemical techniques, the amounts of sugar, glycogen, lipid and protein in each individual were established quantitatively.
3. There was no significant size difference between lekking and resting males. However, lekking males were significantly heavier and contained significantly more sugars and protein than resting males.
4. In conclusion, leks are exclusive, and only males with adequate nutritional reserves may join. Thus, in this species, reproductive success is closely linked to foraging success. 相似文献
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Cyclic AMP and GA3 stimulated both -amylase activity in riceendosperm and the germination of the seed. In combination theyalso induced germination of ABA-treated seeds but cyclic AMPalone failed to neutralize the inhibitory effect of ABA; withadded kinetin, however, it promoted the -amylase activity ofthe dormant seeds. The enzyme activity decreased as the storageperiod of seeds increased. Cyclic AMP and GA 相似文献