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61.
番茄(Solanum lycopersicum L.)开花时间直接决定后期的产量和经济效益。为了探讨番茄 SlSP5G3基因功能,以‘Micro-Tom’番茄为试验材料,观察 SlSP5G3基因时间和空间的变化规律及对番茄开花和产量的影响。结果发现 SlSP5G3的表达响应光周期变化,主要在叶片中表达,且表达量不受生长发育时期的影响。在‘Micro-Tom’番茄中过表达 SlSP5G3,获得过表达植株L8和L12。与野生型植株相比,L8和L12植株开花所需叶片数分别增加2.34和2.67片;叶片鲜质量分别增加98.43%和76.89%;叶片干质量分别增加62.79%和41.86%;果实单果质量分别增加49.65%和36.13%;单株产量分别增加34.50%和26.74%,并且 SlSP5G3过表达植株还显著提升了上游开花转录因子 SlCDF3的表达量。 SlSP5G3通过调控开花时间,改变植株生长形态,对提升植株产量产生重要影响。 相似文献
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蝴蝶兰商品化大规模栽培非常成功,在花卉市场所占比重越来越大。为了在国内生产环境下生产出更高品质的蝴蝶兰商品花,本文从品种、温度、光照、水分、气体、肥料等方面对蝴蝶兰成花品质的影响因素进行综述,旨在解决营养生长、昼夜温差等因素对成花品质的影响,以期为蝴蝶兰工厂化生产提供一定的理论支持。 相似文献
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Urbanization has negative effects on plant-animal interactions by reducing plant richness and increasing resource limitations. However, it is possible to replant these areas, and plant species can be selected based on the resources they provide, as well as their relationships with animals. I observed several trees of Ceiba pubiflora (Malvaceae, Bombacoideae) to identify the bird species interacting with their flowers in an urban area. This plant may be especially important, as it blossoms during the dry season, when the overall flower availability in the study area is low. It may also be important during a short period of decline in the fleshy fruit supply. Even though C. pubiflora was growing in the city and had a low volume of nectar accumulating in its flowers (mean of 1.73 μl; SD = 1.39 μl), it attracted a variety of birds (25 species belonging to six families), some of which are usually regarded as forest dependent. Nectarivorous birds from the family Trochilidae (hummingbirds, n = 12 species) had the highest percentage of visits (64.08%), especially during periods of relatively high nectar sugar concentration and calorie availability (c. 18% and 1.5 cal., respectively). Hummingbirds primarily acted as nectar thieves but also sometimes as potential flower pollinators. In contrast, several nonnectarivorous birds (frugivore-granivores, frugivore-insectivores and omnivores) acted only as nectar robbers or flower predators. Ceiba pubiflora flowers appear to be an important source of energy for birds in the urban area. The data of this study show that C. pubiflora has utility as management tool to promote and conserve biodiversity in cities. 相似文献
65.
The effect of night temperature on short day (SD) floral induction has been studied in three June-bearing strawberry cultivars of different geographic origin and compared with yield performance in the cool Nordic environment. At the optimum day temperature of 18 °C, the SD flowering response of the cultivars ‘Florence’ and ‘Korona’ increased significantly with increasing night temperature from 9 to 18 °C, while an optimum was reached at 15 °C in the cultivar ‘Frida’ that is selected under cool-environment conditions in Norway. Also, while saturated flowering response was obtained with 3 weeks of SD treatment at all temperatures in ‘Frida’, several plants of ‘Florence’ and ‘Korona’ failed to initiate flowers at 9 °C night temperature even with 5 weeks of SD. The effect of extended SD period was particularly pronounced in ‘Florence’. The slow SD floral induction response of ‘Florence’ was associated with a 2 week delay of anthesis in subsequent long day (LD) conditions at 21 °C. Yield performance of the same cultivars during 2 years under field conditions at Nes Hedmark and in North Norway also demonstrated that the yield potential of ‘Florence’ was not realized under the climatic conditions prevailing at these locations. In both years the yields varied significantly among the cultivars, ‘Frida’ having the highest yields followed by ‘Korona’, with ‘Florence’ far below. It is concluded that, in the Nordic environment, autumn (September) night temperatures are obviously sub-optimal for yield performance of some June-bearing strawberry cultivars, and that this effect is mediated by autumn temperature effects on flower initiation responses. 相似文献
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观察中华和美味猕猴桃优良品种在南京地区开花物候期,为其花期管理和授粉提供理论依据。笔者田间观察记录中华猕猴桃和美味猕猴桃的初花期、盛花期、末花期和坐果期,并统计不同猕猴桃品种的花期长度。结果表明,中华和美味猕猴桃的花期集中在4 月中旬—5 月上旬,‘红阳’的初花期最早,为4 月10 日,‘海沃德’初花期最晚,为5 月3 日,两者相差24 天。并且不同猕猴桃品种的花期长短不一,‘翠玉’的花期最长,为17 天,而‘金魁’的花期最短,仅5 天。中华猕猴桃的初花期比美味猕猴桃早,并且花期比美味猕猴桃长。 相似文献
69.
[目的]研究不同生境下泽兰实蝇的寄生状况及其影响因素。[方法]通过对云南大中山地区紫茎泽兰入侵生境中泽兰实蝇的寄生状况抽样调查,分别从环境因素和紫茎泽兰生长状况两方面,分析了影响泽兰实蝇寄生的因素。[结果]不同生境泽兰实蝇的寄生状况有显著差异,其中林区公路和林区空旷地寄生率、虫瘿数和虫瘿内幼虫数最高,显著大于华山松林和落叶阔叶林。乔木层盖度与泽兰实蝇的寄生率、虫瘿数、虫瘿重呈显著负相关,而灌木层盖度与泽兰实蝇的寄生率呈显著正相关。泽兰实蝇寄生率与紫茎泽兰均高和开花率均呈极显著的正相关。[结论]开阔的生境有助于泽兰实蝇的寄生和扩散,林下的光照条件对泽兰实蝇的寄生亦有影响。泽兰实蝇偏好寄生林区公路边和林区空旷地植株较大、分枝较多的植株,泽兰实蝇对花期的植株可能更具有趋性。 相似文献
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[目的]研究金银花开花过程中花瓣几种酶活性的变化。[方法]以金银花不同花期(米蕾期、三青期、二白期、大白期、银花期、金花期)的花朵为试验材料,研究金银花开花过程中可溶性蛋白质和丙二醛(MDA)含量、超氧化物歧化酶(SOD)和过氧化物酶(POD)活性的变化。[结果]在金银花开花过程中,随着花瓣可溶性蛋白质含量的下降,超氧化物歧化酶(SOD)、过氧化物酶(POD)的活性也随之下降;从银花期到金花期,随花色的变化,丙二醛(MDA)含量逐渐增加。[结论]该研究可为金银花花色变化的生理机制研究提供科学依据。 相似文献