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1.
Summary A 6×6 diallel was prepared to study the inheritance of leaf angle in T. aestivum L. Genetic analysis in terms of diallel cross parameters and graphic analysis indicated the control of additive gene effects in the expression of this character. The results of F1 analysis were supported by the analysis of F2 data. 相似文献
2.
Raspberry (Rubus idaeus) leaves, collected in different locations of Lithuania were extracted with ethanol and the extracts were tested for their antioxidant activity (AA) by using ABTS(.)(+) decolourisation and DPPH(.) scavenging methods. All extracts were active, with radical scavenging capacity at the used concentrations from 20.5 to 82.5% in DPPH(.) reaction system and from 8.0 to 42.7% in ABTS(.)(+) reaction. The total amount of phenolic compounds in the leaves varied from 4.8 to 12.0 mg of gallic acid equivalents (GAE) in 1 g of plant extract. Quercetin glucuronide, quercetin-3-O-glucoside and rutin were identified in the extracts. 相似文献
3.
中国饮茶方式历经了由唐以前的生煮羹饮、唐代的煎茶、宋代的点茶到明清瀹饮法的漫漫演进,中国饮茶方式的历史演变也是中华茶文化发展进程的缩影,也是中华茶文化的精华所在。 相似文献
4.
我国银杏产业现状及对策 总被引：2，自引：2，他引：2
阐明发展我国银杏产业的重要意义，总结当前的现状和存在问题，并进一步发展银杏产业的几点意见。 相似文献
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通过盆栽试验,研究了不同土壤铅浓度对茶叶生长及叶片生理特性的影响。结果表明,随着土壤铅浓度的升高,夏茶叶绿素含量显著下降,并有失绿现象,茶树生长受到一定程度的抑制。春茶叶绿素含量呈上升趋势,夏茶叶绿素含量呈先增加后降低的趋势。当铅浓度为100mg·kg-1时,叶绿素含量达到最大值2.93mg·g-1;铅浓度为1500mg·kg-1时,叶绿素含量达到最小值2.28mg·g-1;随铅浓度增加,叶片中游离脯氨酸、丙二醛含量显著增加,两者与铅浓度呈显著正相关,春茶的相关系数分别为0.922（P〈0.01）和0.880（P〈0.01）,夏茶的相关系数为0.871（P〈0.05）和0.971（P〈0.01）,且夏茶中的游离脯氨酸、丙二醛含量大于春茶。铅对春茶、夏茶中可溶性糖的合成有一定的抑制作用,相关系数分别为-0.715（P〈0.01）和-0.912（P〈0.01）。在铅浓度为0～200mg·kg-1时,春茶可溶性糖有小幅度增加;在铅浓度为200mg·kg-1时,春茶、夏茶可溶性糖含量都同时达到最大值。 相似文献
7.
银杏种子氨基酸成分和微量元素的测定 总被引：3，自引：0，他引：3
本文分析４个银杏品种种子中的氨基酸成分和微量元素的含量。其中含有人体所必需的１２种营养元素，氨基酸的总含量高达５．５３％─９．０６％。 相似文献
8.
Xiang LI;Zhiyou YUAN;Feng JIAO 《水土保持研究》2023,30(02):87-92
In order to further improve the plant nutrient cycle model in China, we used meta-analyses to collect 51 published studies to explore the different N/P resorption pattern between herbs, shrubs and trees and the relationships between N/P resorption, temperature and precipitation in China. The results showed that:(1)average N contents of senesced leaves in herbs, shrubs and trees were 9.05 mg/g, 14.91 mg/g, 12.72 mg/g, respectively; average P contents of senesced leaves of herbs, shrubs and trees were 0.50 mg/g, 0.79 mg/g, 0.76 mg/g, respectively; average N resorption efficiencies of herbs, shrubs and trees were 64.16%, 51.97% and 35.82%, respectively; average P resorption efficiencies of herbs, shrubs and trees were 65.51%, 46.74% and 41.72%, respectively;(2)N and P contents of senesced leaves of herbs were significantly lower than those of shrubs and trees; N and P resorption efficiencies of herbs were significantly higher than those of shrubs and trees; N resorption efficiency of shrubs was significantly higher than that of trees; There was not remarkable difference to other variables of nutrient resorption between shrubs and trees;(3)N and P contents of senesced leaves were positively correlated with temperature; there was a negative relationship between N resorption efficiency and temperature, while P resorption efficiency was not related to temperature; N content of senesced leaves and N resorption efficiency were positively and negatively correlated with precipitation, respectively; there was no correlation between P content of senesced, P resorption efficiency and precipitation; this result indicated that the high nutrient resorption efficiency of herbs might reflect that the regeneration rate of herbs was higher than that of shrubs and trees; it also indicated that different life-form plants had various nutrient adaptation strategies to the environment shifts. In this study, N resorption was more sensitive to the changes of precipitation and temperature than P resorption. It suggested that the strategy of plant N uptake and utilization might be more flexible than that of P along the climate gradients. The response of N and P resorption pattern to temperature and precipitation may imply the difference adaptability of plant to hydrothermal conditions under the climate change. 相似文献
9.
Zhen Yang Xin Li Ning Zhang Xiaolei Wang Yuna Zhang Yulong Ding Benke Kuai Xueqing Huang 《Plant Breeding》2017,136(2):188-196
Functional stay‐green is generally regarded as a desirable trait of varieties in major crops including maize. In this study, we used an F3:4 recombinant inbred line population with 165 lines from a cross between a stay‐green inbred line (Zheng58) and a model inbred line (B73) using 211 polymorphic simple sequence repeat markers to map quantitative trait loci for three stay‐green‐associated parameters, chlorophyll content, photosystem II photochemical efficiency and stay‐green area, at maturity stage, detected a total of 23 quantitative trait loci (QTL) on nine chromosomes. Single QTL explained 3.7–13.5% of the phenotypic variance. Additionally, we validated some important stay‐green QTL using a heterogeneous inbred family approach and found that the stay‐green‐associated parameters were significantly correlated with the plant yield. This study may contribute to a better insight into the regulatory mechanism behind leaf stay‐green in maize and a novel development of elite maize varieties with delayed leaf senescence through molecular marker‐assisted selection. 相似文献
10.