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正黑杨派无性系在世界发达国家的杨木生产中占有重要经济地位,特别是欧美杨无性系具有较强的杂种优势,表现出早期速生、无性繁殖容易、适应性强等特点,适宜于无性系育种。经长期引种实践和栽植历史证明,其适生于我国大部分平原地区,成为  相似文献   
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不同栽培树形对油橄榄品种果实产量的效应   总被引:1,自引:1,他引:0       下载免费PDF全文
Longnan City in Gansu Province is the largest base of olive production in China. In the olive orchard locating in Wudu District of Longnan City, thirty trees were sampled each of three cultivars, ‘Leccino’, ‘Chenggu32’, ‘Ezhi8’, with monoconical and vase training system. After planted with density of 5×6 m in 1992, each sample tree was investigated to determine the yield fresh fruit in five different years. The results of survey and analysis showed that there were significant differences of fruit yield among 5 years and 3 cultivars. Different canopy shapes yielded some effect on fruit setting rate and yield of different cultivars in different years. During first fruiting period in the fourth/sixth year after planting, fruit setting rate and yield of ‘Leccino’ with monocone were more 6.7% and 0.15 kg than those with vase and those of ‘Ezhi8’ and ‘Chenggu32’ with vase were more 20%, 10% and 0.18 kg, 0.09 kg than those with monocone. With the increase of tree age, fruit set and yield of ‘Leccino’ and ‘Ezhi8’ with vase was more than those of monocone. In 2011, average yields per tree of ‘Leccino’ and ‘Ezhi8’ with vase were more 13.35 kg and 6.85 kg than those with monocone. And the highest yield per tree of ‘Leccino’ with vase was 75 kg, more 16 kg than that of monocone. Fruit trees with yield over 35 kg of ‘Leccino’ and 25 kg of ‘Ezhi8’ with vase accounted for 80% and 46.7%, more 40% and 30.01% than those of monocone. It was concluded that vase training system would produce higher yield of ‘Leccino’ and ‘Ezhi8’ and its effect and advantages were gradually prominent with increase age. As for ‘Chenggu32’, monocone got a slightly higher yield than that of vase and in 2011 fruit trees with yield over 15 kg accounted for 25%, more 8.34% than vase. The difference between two training system of this cultivar was not obvious.  相似文献   
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为客观准确评价重庆市老鹰茶种质资源情况,调查了123份老鹰茶种质资源的生长势、芽叶颜色、发芽密度等形态指标,对其中27份种质的水浸出物、茶多酚、总黄酮、游离氨基酸和可溶性糖等生化成分含量进行分析,并利用等级评分法和因子分析法对老鹰茶种质资源进行综合评价.结果表明:27份种质的平均水浸出物含量为29.25%,WX18的水...  相似文献   
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不同生境条件下凤丹生长及光合特性比较   总被引:1,自引:1,他引:0       下载免费PDF全文
设置林下(郁闭度0.6)和空旷地两种生境,比较不同生境下凤丹生长及光合特性,探讨凤丹优化栽培的合适生境.结果表明:林下生境的凤丹冠幅面积、一级分枝数、单株挂果量及单位冠幅面积挂果量均优于空旷生境,而前者树高略低于后者.林下生境的凤丹叶绿素a和叶绿素b分别高出空旷生境的103.53%和122.86%,差异具有统计学意义(p0.05).在光合日变化规律方面,林下生境的凤丹净光合速率呈现明显的"单峰"曲线,而空旷生境下的呈不明显"双峰"曲线,总体上前者高于后者;前者胞间CO_2浓度和蒸腾速率低于后者而气孔导度无明显变化趋势;林下生境的光能利用效率和水分利用效率普遍显著高于空旷生境.林下生境因存在一定程度的遮荫,阻挡了夏季强光对凤丹的不良影响,同时也减少了林下的光合有效辐射,但凤丹自身的特性或适应性使得光能和水分利用率高,净光合速率高,有机物合成多,分枝多,植物长势好.  相似文献   
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大力发展老鹰茶产业不仅是传统茶饮的发扬光大,还对促进地方经济发展,提高农民收入,乡村振兴有重要作用。文中对老鹰茶作为茶饮的饮用历史、原料植物、开发利用现状及存在的问题进行了概述,并针对存在问题探讨了老鹰茶产业化发展的对策,以期为老鹰茶产业的平稳快速发展提供参考。  相似文献   
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本研究旨在了解重庆合川地区油橄榄树体的营养状况和果实膨大规律及其相关性,为该地区油橄榄的平衡有效施肥提供依据,实现丰产优质栽培的目的。以不同生长时期内3株树势相同,无病虫害的7年生‘豆果’油橄榄树为研究材料,基于硝酸—盐酸—高氯酸消煮—ICP法测定叶片和果实中大量和微量元素P、K、Ca、Mg、Fe、Mn、Cu、Zn含量,凯氏定氮法测定元素N含量,游标卡尺测定果实纵横径。结果表明:“豆果”生长期内,大量元素在叶片和果实中随果实膨大存在不同变化趋势。总体上,叶片中大量元素含量趋势为K>Ca>N>P>Mg;果实中大量元素含量趋势为K>N>Ca>P>Mg。对微量元素Fe的需求量明显高于元素Mn、Zn、Cu,且叶片中元素Fe远高于果实中的。叶片内部-果实内部-叶片-果实间矿质元素含量以及果实膨大-叶片果实矿质元素含量存在普遍的显著相关性。从矿质元素在“豆果”叶片、果实中的含量动态变化趋势来看,营养元素N、K、Ca在发育期中一直保持相对较高水平,肥料施用上应充分满足;考虑到元素间的拮抗和协同关系,建议生产上施用N肥时还应搭配P肥、K肥、微量元素肥(含Cu和Zn)施用,以达到丰产优质栽培的目的。  相似文献   
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