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61.
《Plant Production Science》2013,16(2):185-192
Abstract

Rice productivity is related to the ability of plants to adapt to heat stress. The heat-tolerant cultivars ‘Nikomaru’ and ‘Chikushi 64’ and heat-sensitive cultivar ‘Hinohikari’ were grown at 30ºC and 25ºC for 49 days after flowering. At 30ºC, only a few white immature kernels were produced in ‘Nikomaru’ and ‘Chikushi 64’, but about 22% of grains had immature kernels in ‘Hinohikari’. The high temperature(30ºC) caused no significant changes in grain dry weight, water content, and the NMR T1 value during the early ripening stage in ‘Nikomaru’ and ‘Chikushi 64’. It also did not affect grain development, especially with respect to the nucellar epidermis, in ‘Nikomaru’ and ‘Chikushi 64’, but caused clear cessation of development of the nucellar epidermis at 14 days after flowering in ‘Hinohikari’. In addition, high temperature decreased the amylose content and increased hardnessvs. adhesion ratio of cooked rice in both ‘Nikomaru’ and ‘Chikushi 64’ resulting a softer, less sticky texture, but not in ‘Hinohikari’. The maximum viscosity and breakdown values were increased, and final viscosity decreased at 30ºC in all three cultivars. These results suggested that starch in the endosperm of grains changed from a fluid state to a doughy state more slowly in ‘Nikomaru’ and ‘Chikushi 64’ than in ‘Hinohikari’, in which the water content and NMR relaxation time decreased, and transported assimilates accumulated slowly during grain development.  相似文献   
62.
《African Zoology》2013,48(1):78-91
Photo-identification surveys over three years along 390 km of coastline north of Cape Town, revealed that Heaviside’s dolphin distribution was consistent between years and higher in areas more exposed to swells and with greater long-term availability of small hake Merluccius capensis (their principal prey). Dusky dolphin sighting rates varied considerably between years, but were generally higher in areas with lower hake availability and sandier shores (mostly straighter coastline). Large groups of 50–200 dusky dolphins were only seen in St Helena Bay, the site of a wind-driven upwelling zone. Heaviside’s dolphins were found in shallower, cooler water than dusky dolphins and were more likely to be seen during brighter phases of the moon (when nocturnal light conditions may influence the vertical migration patterns of prey) and in areas of high hake abundance. Near-shore fishing activity was higher in the northern half of the study area and clustered around harbours. Set netting occurred only at Yzerfontein and St Helena Bay, but due to changes in the industry is currently thought to be a low threat to the population. Interactions between Heaviside’s and dusky dolphins were usually neutral and sympatry appears to be mediated by differences in overall range and the type and size of prey species taken.  相似文献   
63.
林蕊桂 《茶叶》2009,35(3):178-179
本文阐述了蕉城区名优茶质量评比的参评情况并对其结果进行研究分析,提出了茶产业发展的对策。  相似文献   
64.
种植密度与底磷肥用量对绿豆产量的影响   总被引:3,自引:0,他引:3  
通过2因子4水平复因子试验与统计分析,研究了绿豆种植密度和底磷肥施用量对绿豆产量的影响。结果表明,绿豆种植密度和底磷肥施用量,是决定绿豆产量的主要因素。明确了绿豆的最佳种植密度和底磷肥施用量。  相似文献   
65.
The influence of 9 rootstocks (M2, M7, M25, M26, MM104, MM106, MM109, MM111 and seedling) on fruit quality at harvest and after storage of ‘Wellspur Delicious’ (WS) and ‘Goldspur’ (GS), and of 3 rootstocks (M7, M26 and MM106) on fruit quality of ‘Red King Delicious’ (RK) and ‘Golden Delicious’ (GD) apple (Malus domestica Borkh.) was evaluated during a 4-year period. Fruits from trees on M26 were larger, developed earlier color and soluble solids (SS), and maintained higher levels of acidity (at harvest and during storage) in comparison with other rootstocks. Fruit from trees on M2 tended to have high SS. Fruit color from trees on MM104, MM106 and MM109 tended to be comparatively poor. There were significant rootstock effects on SS, starch, acidity, color, circumference, weight and box size.  相似文献   
66.
比较了4种土壤类型和3种留茬高度对威提特东非狼尾草(Pennisetum clandestinum cv. Whittet)种子产量和质量的影响。结果表明:以单因素而言,生土处理和0.05 m留茬高度处理所获得的平均种子产量最高;两因素处理的结果表明,以生土和0.05 m留茬高度互作后所获得的种子产量最高,其种子产量达447kg/hm2;各土壤类型和不同留茬高度的处理对种子的质量影响差异不显著。  相似文献   
67.
指出了木材干燥窑壳体传热量的传统计算方法中的不足,并利用形状因子法来分析计算木材干燥窑壳体的传热量.对比2种计算方法所得的结果表明,传统的干燥窑壳体计算方法较为保守,而根据形状因子法计算结果来配置干燥窑的加热器面积则不会造成干燥窑中散热设备投资的浪费,同时也可以节省干燥窑墙体设计用材的量.  相似文献   
68.
A comparison was made of the response to storage temperatures (0–17°C) of grapefruit ‘Shamouti’ and ‘Valencia’ oranges, and lemon fruit. There was no chilling injury (CI) and the incidence of rot was relatively low at 12°C or higher for all cultivars. At low storage temperatures, however, pitting and subsequent rot development in grapefruit and in ‘Shamouti’ and ‘Valencia’ oranges were highest at 6°C, while in lemon the incidence of these disorders rose with the decrease in storage temperature, and was highest at 2°C. Grapefruit and ‘Shamouti’ oranges exhibited the highest susceptibility to CI, lemon showed an intermediate susceptibility, and ‘Valencia’ orange a very low one. In grapefruit, severe peel pittings that developed in cold storage were covered by mold rots during cold storage and shelf-life, but in ‘Valencia’ and particularly in ‘Shamouti’ oranges the incidence of decay during cold storage was low. During shelf-life, a pronounced CI-induced increase in the incidence of mold rots was evident. This breakdown during shelf-life may be associated with microscopic peel injuries which are formed during cold storage and covered by mold rots during shelf-life. Increased susceptibility of the cultivar to CI could be correlated with an increase in ethanol content at low temperatures.  相似文献   
69.
70.
为研究低海拔区域浙江红花油茶无性系开花物候特性,对浙江金华东方红林场的22个浙江红花油茶无性系开花物候、花期长短、开花数量进行了调查观测。结果表明:低海拔地区浙江红花油茶无性系花期始于1月下旬,结束于4月中下旬,花期长达62.5 d,花期较集中,但开花期容易受到气候的影响。不同浙江红花油茶无性系开花物候差异显著,开花期最早的是无性系dy144,最晚的是无性系hy31。花期持续时间最长的是无性系hy54、hy179,花期持续时间均值为53.5 d;最短的是无性系hy58,花期持续时间均值为26.5d。22个无性系之间开花数量存在极显著差异(P<0.01)。根据本试验的研究结果,其中无性系dy156、hy8、hy28、hy31、hy43、hy47、hy59、hy63、hy54、hy71、hy179可以考虑作为园林观赏推广品种。  相似文献   
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