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1.
Physiological integration in Cassia fasciculata Michx.: inflorescence removal and defoliation experiments 总被引:3,自引:0,他引:3
Summary In the annual herb Cassia fasciculata virtually every leaf subtends an axillary inflorescence. We examined the degree to which these leaf-inflorescence units (reproductive nodes) were physiologically independent of each other in the production of flowers, fruits, and seeds. Removal of up to 4 of every 5 inflorescences resulted in substantial increases in fruit and seed production by remaining, intact reproductive nodes. These increases nearly compensated for and manipulated reproductive nodes were associated with different vascular strands. When 2 of every 3 leaves were removed, fruit and seed production were reduced at both intact and defoliated reproductive nodes. Taken together, these results suggest that neighboring reproductive nodes in C. fasciculata are not physiologically independent of one another, and that competition among fruits and seeds for parental resources occurs over several reproductive nodes.Scientific contribution no. 1595 from the New Hampshire Agricultural Experiment Station 相似文献
2.
森林土壤是CO2、CH4和N2O等温室气体的主要排放源.本研究采用静态箱/色谱分析技术,对中国科学院鹤山丘陵综合开放试验站内厚荚相思林土壤CO2、CH4和N2O通量进行原位测定,研究剔除林下灌草和添加翅荚决明对土壤温室气体排放的影响.结果表明:厚荚相思林土壤CO2通量在湿季维持较高水平,在旱季则明显降低.CH4和N2O在9-11月波动幅度较大,峰值出现在10月.在不同处理下,厚荚相思林土壤可能是CH4的源也可能是CH4的汇,而于CO2和N2O则是源.林下剔除灌草能显著增大土壤CO2排放(P<0.05),而添加翅荚决明能加快土壤CH4的排放(P<0.05).林下剔除灌草及添加翅荚决明两种处理都能够加大N2O的排放通量.表层土壤温度、湿度、NO3--N和微生物生物量碳都是影响土壤温室气体排放的重要因子. 相似文献
3.
Fumio Okada Tadakazu Takeo Shoji Okada Osamu Tamemasa 《Bioscience, biotechnology, and biochemistry》2013,77(5):791-794
Theaflavins, the oxidized products formed from tea leaf catechins during black tea fermentation, showed an antiviral activity on TMV. From the survey of the interactions of theaflavins with RNA and its related substances, it was presumed that theaflavins disturbed the replication cycle of TMV through binding to TMV-RNA. 相似文献
4.
豆茶决明也Cassia nomame ( Sieb.) Kitag.页为云实科( Caesalpiniaceae)决明属( Cassia Linn.)一年生草本植物[1],其地上部分及种子可入药,主治水肿、肾炎、慢性便秘、咳嗽和痰多等,并具有驱虫、健胃之功效,也可代茶饮用[2],在药理和保健方面具有多重功效,是极具开发潜力的野生植物资源。目前仅燕山山脉的河北省青龙满族自治县每年就有近1000 t的豆茶决明全草出口,而且燕山山脉民间还有用豆茶决明种子做酱的习惯,致使豆茶决明野生资源面临枯竭的境地。目前,对豆茶决明的研究还非常有限,尤其在资源调查、引种、栽培和开发等方面。 相似文献
5.
The hepatoprotective and antioxidant effect of Cassia fistula Linn. leaf extract on liver injury induced by diethylnitrosamine (DEN) was investigated. Wistar rats weighing 200+/-10g were administered a single dose of DEN (200mg/kg b.w., i.p.) and left for 30 days. For hepatoprotective studies, ethanolic leaf extract (ELE) of C. fistula Linn. (500mg/kg b.w., p.o.) was administered daily for 30 days. AST, ALT, ALP, LDH, gamma-GT and bilirubin were estimated in serum and liver tissue. Lipid peroxidation (LPO), SOD and CAT were also estimated in liver tissue as markers of oxidative stress. DEN induced hepatotoxicity in all the treated animals were evident by elevated serum ALT, AST, ALP and bilirubin levels and a simultaneous fall in their levels in the liver tissue after 30 days. Induction of oxidative stress in the liver was evidenced by increased LPO and fall in the activities of SOD and CAT. ELE administration for 30 days prevented the DEN induced hepatic injury and oxidative stress. In conclusion, it was observed that ELE of C. fistula Linn. protects the liver against DEN induced hepatic injury in rats. 相似文献
6.
Cícero Nicolini Renato O. Resende Genira. P. Andrade Elliot W. Kitajima Gilvan
Pio‐Ribeiro Tatsuya Nagata 《Journal of Phytopathology》2012,160(2):82-87
Cowpea aphid‐borne mosaic virus (CABMV) causes major diseases in cowpea and passion flower plants in Brazil and also in other countries. CABMV has also been isolated from leguminous species including, Cassia hoffmannseggii, Canavalia rosea, Crotalaria juncea and Arachis hypogaea in Brazil. The virus seems to be adapted to two distinct families, the Passifloraceae and Fabaceae. Aiming to identify CABMV and elucidate a possible host adaptation of this virus species, isolates from cowpea, passion flower and C. hoffmannseggii collected in the states of Pernambuco and Rio Grande do Norte were analysed by sequencing the complete coat protein genes. A phylogenetic tree was constructed based on the obtained sequences and those available in public databases. Major Brazilian isolates from passion flower, independently of the geographical distances among them, were grouped in three different clusters. The possible host adaptation was also observed in fabaceous‐infecting CABMV Brazilian isolates. These host adaptations possibly occurred independently within Brazil, so all these clusters belong to a bigger Brazilian cluster. Nevertheless, African passion flower or cowpea‐infecting isolates formed totally different clusters. These results showed that host adaptation could be one factor for CABMV evolution, although geographical isolation is a stronger factor. 相似文献
7.
Oxanthrone esters from the roots of Cassia kleinii 总被引:1,自引:0,他引:1
From the roots of Cassia kleinii two new oxanthrone esters, kleinioxanthrone-3 and kleinioxanthrone-4 have been isolated. Their structures were established as 1,8-dihydroxy-3-methyl-9(10H)-anthracenone-10-oxyhexadecanoate 3 and 2,6,7-trihydroxy-1,8-dimethoxy-3-methyl-9(10H)-anthracenone-10-oxydecanoate 4 respectively based on degradative and spectroscopic evidence. 相似文献
8.
决明胰蛋白酶抑制剂1(CoTI1)属于Kunitz胰蛋白酶抑制剂家族成员,通过序列比对预测Arg86、Leu84和Thr88等3个氨基酸残基可能是CoTI1发挥抑制作用的关键残基。通过定点突变的方法将Arg86、Leu84与Thr88残基分别突变为Asp残基,并考察各突变体对胰蛋白酶及棉铃虫等鳞翅目害虫消化酶的抑制作用。与CoTI1相比,CoTI1R86D、CoTI1T88D与CoTI1L84D突变体对胰蛋白酶的抑制活性分别下降了93%、64%与59%;对棉铃虫、甜菜夜蛾、斜纹夜蛾等3种鳞翅目害虫消化酶的平均抑制活性分别下降了88.7%、57%与60.7%。以上结果表明Arg86、Leu84与Thr88是CoTI1发挥抑制作用的关键残基,这为CoTI1的抑制分子机制及抗虫研究提供了重要的理论依据。 相似文献
9.
An efficient, rapid and reproducible plant regeneration protocol was successfully developed for Cassia angustifolia using nodal explants excised from 14-day-old aseptic seedlings. Of the two cytokinins, 6-benzyladenine (BA) and thidiazuron
(TDZ) evaluated as supplements to Murashige and Skoog (MS) medium, TDZ at an optimal concentration of 5.0 μM was effective
in inducing multiple shoots. The highest rate of shoot multiplication was achieved on MS medium supplemented with 5.0 μM TDZ
and 1.0 μM indole-3-acetic acid (IAA) at pH 5.8. The regenerated shoots when subcultured on hormone free MS medium considerably
increased the rate of shoot multiplication and shoot length by end of fourth subculture passage. Rooting was achieved on the
isolated shoots using MS medium with 60 μM indole -3- butyric acid (IBA) and 1% activated charcoal for 1 week and subsequently
transferring the shootlets to half strength MS liquid media without IBA and activated charcoal. The in vitro raised plantlets
with well-developed shoot and roots were successfully established in earthen pots containing garden soil and grown in greenhouse. 相似文献
10.