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61.
The relationship between the relative growth rate (RGR) and the nitrogen concentration of the whole plant (PNC) was analyzed by using experimentally determined relations (1) between the PNC and the fraction of dry matter (LWR) and nitrogen in leaves, (2) between the specific leaf area (SLA) and the leaf nitrogen concentration (LNC) and (3) between the net assimilation rate (NAR) and the LNC on an area basis. A strong dependence of RGR on nitrogen concentration resulted from the increase in NAR, LWR and SLA with increasing PNC. A curvilinear relationship between RGR and PNC gave an optimum curve for nitrogen productivity against PNC.  相似文献   
62.
Our primary focus in this research was to identify and characterize its bioactive compounds for potential therapeutic use. Twenty-seven metabolites of Polygonum orientale were identified using LC-QTOF tandem mass spectrometry. Interestingly, P. orientale extracts included several highly oxygenated flavonoids were isolated from P. orientale by column chromatography. 13C NMR data of highly oxygenated flavonoids (1–7) are reported here for the first time. In addition, nitric oxide, 1,1-diphenyl-2-picrylhydrazyl, and water-soluble tetrazolium salt assays were carried out on the isolated compounds to investigate their anti-inflammatory, anti-oxidant, and neuroprotective activities, respectively. Compounds 1, 2, 3, 5, 7, and 8 significantly attenuated lipopolysaccharide-stimulated NO production in BV2 cells without affecting cell viability. Compounds 9–12 exhibited significant antioxidant activity, while compounds 8, 9, and 12 exhibited protective effects against glutamate-induced neurotoxicity in HT22 cells. Our results indicate that P. orientale is a promising source of natural agents for the potential treatment of inflammation and neurodegenerative diseases.  相似文献   
63.
64.
Measurements of photosynthetic activity ofPolygonum weyrichii var.alpinum were carried out in a field at the timberline of Mt. Fuji and in the laboratory in summers of 1982 and 1983. In order to measure photosynthesis at remote alpine locations, measurement systems were divided into several units small enough for carrying by one person. In addition, special care was taken in collecting and transporting plant materials for photosynthetic measurement in the laboratory. Good agreement was found for the light-photosynthesis curves between the field and laboratory measurements.  相似文献   
65.
Abstract. 1. Observations were made on the biology of Gastrophysu polygoni (L.) (Coleoptera: Chrysomelidae) in cereal fields in southern England in 1977, 1978 and 1979. Adults of the overwintering generation emerged in late April/ May and there were usually two generations during the spring and summer months. In 1979 there was some evidence for at least a partial third generation.
2. In the field, the oviposition period was 44 days in the first generation and c . 25 days in the second. Fecundity varied from 586 to 1028 eggs per female and was higher in the first than in the second generation in both 1977 and 1979; in 1978 the reverse was true.
3. Every year there were Iarge losses in the numbers within a generation. However, only one parasite was bred from the developmental stages and a pathogen attacking the larvae was found only in 1977.
4. In some fields and in some years, harvesting and straw burning operations were carried out when eggs were present on the plants. Harvesting did not result in a significant reduction in the numbers of eggs. Burning reduced the numbers of egg batches. The effect was most severe when the straw was spread over the field prior to burning.
5. In the field, significantly more eggs were laid on plants of Polygonum aviculare than on P.convolvulus . In the laboratory, larval survival was higher and duration of development shorter on these two species than on other Polygonaceae found on the farm.  相似文献   
66.
采用光学显微镜对中国蓼属分叉蓼组(Polygonum section Aconogonon)和冰岛蓼属(Koenigia)的21种植物的叶下表皮微形态进行了观察研究。结果表明,其叶下表皮微形态特征可分为三种类型:(1)气孔器类型为无规则型,表皮细胞多边形,垂周壁为波状;(2)气孔器类型为无规则型兼有非典型不等型,表皮细胞为多边形或不规则形,垂周壁为平直弓形或波状;(3)气孔器类型为不等细胞型,表皮细胞多边形,垂周壁为平直弓形。分叉蓼组(西伯利亚蓼除外)植物的叶表皮气孔器类型具有高度一致性,说明该组是一个自然类群。本文研究结果不支持将大铜钱叶蓼(Polygonum forrestii Diels)、铜钱叶蓼(P. nummularifolium Meissner)划归于冰岛蓼属的处理意见;支持将西伯利亚蓼(P. sibiricum Laxm.)独立成属,即西伯利亚蓼属(Knorringia Tzvel.)的观点;同时也支持仍将多穗蓼(P. polystachyum Wall.ex Meissner)和松林蓼(P. pinetorum Hemsl.)归在分叉蓼组的处理意见。  相似文献   
67.
郑磊  刘关君  杨传平 《植物研究》2007,27(2):212-217
以3% NaHCO3溶液胁迫处理48 h的西伯利亚蓼为试材,利用RACE技术,从其茎部组织克隆了脱水应答蛋白RD22的全长cDNA序列。测序后的结果分析表明,该cDNA序列全长为1 302 bp,5′非翻译区为59 bp,3′非翻译区为25 bp,开放读码框为1 218 bp,编码405个氨基酸。在氨基酸序列的C端含有一个比较保守的BURP结构域,N端含有5个重复序列THV-VGKGGV-V。信号肽检测证明该蛋白为分泌性蛋白,前21个氨基酸区域为信号肽结构。其推演的氨基酸序列与葡萄的同源性最高,达到60%。该基因已在GenBank上注册,基因序列登录号为DQ836050。  相似文献   
68.
The aphid genus Blackmania gen. nov. is described. In the genus, B. eastopi sp. nov. associated with Polygonum equisetiforme (Polygonaceae) from Israel and Cyprus is described and illustrated. Morphologically, the new genus is similar to the genus Acaudella in respect to the lack of a cauda. Acaudella puchovi, associated with Atraphaxis caucasica (=A. buxifolia) and A. spinosa (Polygonaceae) from Uzbekistan and Israel, is re‐described and the apterous viviparous female is figured for the first time. The lectotype and paralectotypes of A. puchovi are also designated. An identification key to known species of the tribe Macrosiphini without cauda is provided. The morphological separation of B. eastopi gen. nov., sp. nov. from A. puchovi is visualized using principal component analysis.  相似文献   
69.
考察了外植体、培养基及光照条件对中药植物虎杖愈伤组织形成及次生代谢产物生产的影响。总的来看,所有愈伤组织中总酚和总黄酮含量比原植物的含量高2—3倍;而蒽醌的含量比原植物中含量低。外植体对愈伤组织形成及次生代谢产物生产的影响很大,所考察的3种外植体中。叶外植的愈伤组织诱导率最高而源于根外植体的愈伤组织具有最好的次生代谢能力。所考察的6种培养基中,MS+0.5mg/L 2,4-D+1.0mg/L 6-BA和N6+0.5mg/L 2,4-D+1.0mg/L 6-BA无论对于愈伤组织的产生还是次生代谢产物的累积都有较优表现。光照对愈伤组织诱导及次生代谢产物产生有明显影响。但二者无规律性联系。  相似文献   
70.
杠板归(Polygonum perfoliatum L.)的系统位置一直存在争议,文中以塔黄为外类群,采用最大简约法对杠板归及其近缘类群的trnL-F序列进行了系统发育分析,结果表明:(1)杠板归和刺蓼为姊妹群,自展分析的支持率为99%,分子证据支持杠板归归人刺蓼组,而没有必要单立组或属。(2)刺蓼组、春蓼组和头状蓼组植物聚在一起,自展支持率为100%,说明它们之间有很近的亲缘关系。  相似文献   
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