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41.
This study characterizes biologically active compounds of berry fruits, including non-nutritive compounds such as phenolic compounds, including anthocyanins, phenolic acids, stilbens and tannins, as well as nutritive compounds such as carotenoids and vitamin C. It discusses the biological activity of those compounds, in particular their antioxidant properties and the resulting health benefits.  相似文献   
42.
不同品种大果沙棘种子特性研究   总被引:7,自引:3,他引:4       下载免费PDF全文
在黑龙江绥棱和内蒙古磴口试验区对俄罗斯11个大果沙棘品种和蒙古1个大果沙棘品种的种子特性进行了探讨,结果如下:(1)中国沙棘种子千粒质量、种子特征值明显低于引进大果沙棘品种.绥棱试验点供试的11个引进品种千粒质量及种子特征值均比磴口试验点高;根据种子长宽比及形状,对中国沙棘与大果沙棘进行了初步的划分.(2)大部分品种种子的宽度及长度在遗传和对环境适应上具有紧密相关性,种子厚度的遗传比较稳定,对环境的变化不敏感.(3)种子特征指标,如种子长度、宽度、长宽比3个指标与千粒质量呈极显著相关,特别是种子长度;千粒质量与百果质量呈现极显著线性相关.(4)发芽初期,中国沙棘的发芽率较引进品种高;发芽第14天时,所有供试品种的发芽率均达到了最大,发芽率高的品种有乌兰格木、丰产、巨人、绥棘1号、卡图尼礼品,发芽率≥67%.(5)不同大果沙棘种子的总黄酮、维生素E含量均具明显差异;引进品种的饱和脂肪酸显著高于中国沙棘;不同大果沙棘品种的饱和脂肪酸差异明显.  相似文献   
43.
在黑龙江绥棱和内蒙古磴口试验区对13个大果沙棘品种的生长性状及其与产量的相关关系进行了研究,结果表明:(1)大果沙棘的叶片长度在不同试验点间差异不明显,磴口试验点的叶片宽度不同程度地比绥棱试验点小,同一试验点不同品种的叶片长度与宽度亦存在一定差异;中国沙棘叶片长度明显小于引进大果沙棘品种,宽度与引进品种相近;磴口试验点叶片长宽比明显高于绥棱,叶片长宽比的大小可作为衡量品种抗逆性或者适应性的一个指标.(2)不同大果沙棘品种的枝刺数具有很大的不同,且同一品种在不同试验点的枝刺数并不完全一致,在磴口试验点,许多品种的枝刺数有明显的增加趋势,这可能是对干旱环境的一种适应或反应;中国沙棘枝刺数量多,为长期适应干旱瘠薄环境的结果.(3)大多数大果沙棘品种在磴口试验点的株高、地径及冠径均低于绥棱试验点,中国沙棘生长旺盛,其株高、地径及冠径均明显大于大果沙棘.(4)品种不同丰产性也不同,而且产量的年度稳定性相差很大,在试验林进入盛果期后,一些大果沙棘品种产量可达到10000kg·hm-2.(5)不同试验点不同品种的生长指标与产量的线性相关性强弱不一致;从生长指标的大小可对产量进行有效预测,而准确的预测还需要进行连续的生长观测和产量测定,以建立完善的沙棘产量预测体系.  相似文献   
44.
 对国家果树种质资源郑州葡萄圃内的94 份无核葡萄和40 份巨峰系葡萄的果粒颜色、形状、质量和大小进行了连续3 年的调查和统计分析。结果表明, 无核葡萄种质果粒质量和果粒大小遗传变异系数比巨峰系大得多, 无核葡萄种质的平均果粒质量主要在110~510 g 的范围内, 将近50 %无核葡萄种质的果粒为115~215 g , 为中等。因此目前国际及国内的现有描述评价标准都不适合评价无核葡萄种质的果粒质量及大小。根据本项研究结果提出了适合无核葡萄种质新的附加分级评价标准。  相似文献   
45.
This paper reports a complete impact data acquisition, processing, and analyzing software system that applies on the hardware platform of the Berry Impact Recording Device (BIRD). The software has three major sections that correspond to the hardware: The BIRD sensor program, the interface box program, and the computer software i-BIRD. The sensor program samples acceleration data from three axes and records them as single impacts with a maximum sampling rate of 3.0 kHz. Users can configure the sensor via the i-BIRD computer software, with different options of sampling frequencies (682-3050 Hz) and thresholds (0-205 g, where g is the gravitational acceleration). The data recorded can be downloaded, processed and graphically displayed on the computer. A real time clock was created using the interrupt service routine provided by the microcontroller. The accuracy of the sensor’s clock was calibrated with an error of 0.073%, which was adequate to record impact data in this application. The shape of impact curves recorded by the BIRD sensor at three sampling frequencies (682, 998, and 1480 Hz) matched well with the curves recorded by a high frequency (10 kHz) data logger with the maximum root mean squared error of 4.4 g. The velocity change had a relative error less than 5%. With confirmation of all those performances, the software system enabled the BIRD to be a useful tool to collect impact data during small fruit (such as blueberry) mechanical harvest.  相似文献   
46.
生长调节物质在巨峰葡萄贮藏中的应用   总被引:1,自引:0,他引:1  
巨峰葡萄采后落粒严重,果梗易失水干枯,贮运难度大,在常规贮藏条件“低温、高湿、防腐”情况下,仅能较好地贮藏3个月左右。应用一定浓度的植物生长调节物质2,4—D、PCPA、NAA等在采前3~5天喷洒果穗,可改善巨峰葡萄贮运性能。其中用“防落1号”处理的果实在上述条件下贮藏4个月以上,腐烂、落粒不超过5%,其中落粒低于2%。采后生理测定表明,“防落1号”处理的果穗,贮藏期间果梗耐拉力增加,呼吸强度低于对照果实,Vc含量高于对照果实。  相似文献   
47.
As part of an overall assessment of the commercial suitability of strawberry cultivars for the Nordic environment, we studied 13 diverse cultivars in an experimental field in South East Norway. Early-maturing cultivars were characterized by early initiation of floral primordia and early flowering and fruit maturation. High temperatures in July and early August delayed floral initiation in the early cultivars, resulting in more synchronous initiation of early and late cultivars. The recent Norwegian cultivar ‘Nobel’, which has an everbearing parent, differed from the other cultivars by early initiation also at elevated summer temperature. Inadequate yield and berry size were identified as important causes for outdating of older cultivars, such as ‘Senga Sengana’ and ‘Glima’. Overall, the high-yielding and large-fruited ‘Sonata’ was judged as the best fresh consumption cultivar in Norway, and market trends indicate that it will continue to expand its market share at the expense of ‘Korona’, mainly because of inadequate fruit firmness and shelf life of the latter. Adequate yields and berry quality justify the use of the late maturing ‘Florence’ for prolongation of the fresh market season. The results are discussed together with practical experiences and market preferences in an attempt to provide overall cultivar recommendations for Norway.  相似文献   
48.
大果沙棘品种适应性及其综合评价   总被引:10,自引:4,他引:6       下载免费PDF全文
在黑龙江绥棱、内蒙磴口及陕西永寿试验区对俄罗斯的12个大果沙棘品种和蒙古的1个大果沙棘品种的适应性进行了综合评价,结果表明:(1)影响大果沙棘在我国的适应性的主要因子是环境因子.在大果沙棘品种的推广中,首先要注意地理位置,其次,在适宜栽培区确定的基础上,还需要考虑品种的适应性差异,即需要进行品种的选择.(2)从高纬度引进的品种,在中国的适应性表现是随着纬度的下降适应性逐渐下降,绥棱试验点、磴口试验点及永寿试验点分属最适引种区、适宜引种区及不适应区.(3)绥棱试验点4 500 kg·hm-2以上的品种有楚伊、浑金、优胜、橙色、阿尔泰新闻、乌兰格木6个品种,磴口试验点6 000 kg·hm-2以上的品种有楚伊、金色、优胜3个品种,这些品种丰产性好,是试验区值得大力推广的引进品种.(4)大果沙棘在中国的适应性区划可分为3个区:最适引种栽培区,如黑龙江绥棱县;适宜引种栽培区,如内蒙古磴口县;栽培驯化区,如陕西永寿县.  相似文献   
49.
Firmness is an essential quality parameter of table grapes (Vitis vinifera) for consumers, with grape bunches that contains soft berries less preferred, resulting in a reduction in the market price. The softening of grape berries has been commonly associated with cell walls, especially the disassembly of pectic polysaccharides. However, the process of berry softening is not completely understood. To investigate the softening process of grape berries, we compared the Thompson Seedless variety, which suffers significant economic losses due to fruit softening, and NN107, a new variety with a significantly higher level of berry firmness. The composition of the cell wall during the berry development of these two grape varieties was compared. NN107 berries had a greater amount of calcium and uronic acids in the cell wall material than Thompson Seedless grapes, suggesting a special role for calcium bridge formation in NN107. Additionally, polyacrylamide carbohydrate electrophoresis (PACE) analysis suggested differences between these varieties in pectin structure. Thompson Seedless grapes showed increased pectolyase hydrolysable site dynamics in the cell wall material and higher polygalacturonase activity than NN107. Immunohistochemistry focusing on the pectin structure confirmed the roles of both calcium bridge formation and cell wall integrity as they relate to a firmer grape berry phenotype.  相似文献   
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