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1.
M. J. van Steenis K. A. M. H. El-Khawass 《Entomologia Experimentalis et Applicata》1995,76(2):121-131
Life table data forAphis gossypii Glover (Homoptera: Aphididae), an important pest in glasshouse cucumber crops, were studied at 20, 25 and 30°C on two cucumber
cultivars (Cucumis sativus L.) in controlled climate cabinets. The development time on the cucumber cv. ‘Sporu’ ranged from 4.8 days at 20°C to 3.2
days at 30°C. Immature mortality was approximately 20% and did not differ between temperatures. Most mortality occurred during
the first instar. Reproduction periods did not differ among temperatures, but at 25 and 30°C more nymphs were produced (65.9
and 69.8 nymphs/♀, respectively) than at 20°C (59,9 nymphs/♀) because of a higher daily reproduction. Intrinsic rate of increase
was greatest at 25°C (r
m
=0.556 day−1). At 20 and 30°C the intrinsic rate of increase was 0.426 and 0.510, respectively. On cv. ‘Aramon’, the development time
ofA. gossypii was approximately 20% longer at all temperatures. Immature mortality did not differ between the two cultivars. The intrinsic
rate of increase on cv. ‘Aramon’ was 15% smaller than on cv. ‘Sporu’. The use of cucumber cultivars partially resistant to
aphids is discussed in relation to biological control of cotton aphid in glasshouses. Development time and immature mortality
on leaves of the middle and upper leaf layer of glasshouse grown cucumber plants (cv. ‘Aramon’) were comparable to development
in the controlled climate cabinets. On the lower leaves immature mortality was much higher (approximately 82%) than on leaves
of the middle (24.0%) and upper leaf layer (24.5%). Reproduction was less on the lower leaf layer (45.9, 70.5 and 70.1 nymphs/♀
on leaves of the lower, middle and upper leaf layer, respectively).
Aphids, successfully parasitized byAphidius colemani Viereck (Hymenoptera: Braconidae) only reproduced when they were parasitized after the third instar. Fecundity was 0.1 to
0.9 and 10.5 to 13.3 nymphs/♀ for aphids parasitized in the fourth instar or as adults, respectively. Reproduction of aphids
that were stung but survived the attack was lower than for aphids not stung. Average longevity of these aphids was equal to
the longevity of aphids not stung byA. colemani. 相似文献
2.
This work was to investigate the effect of flavonoids from Angelica gigas Nakai on the proliferation and differentiation of PC12 cells. Several solvents including hexane, chloroform, ethyl acetate,
butanol and water consecutively partitioned. We determined the ethanol crude extract of Angelica gigas Nakai. The hexane fraction was shown to contain the highest number of flavonoids as follows; 21.48 mg/g and the composition
of the flavonoids was as follows: 12.24 mg/g of quercetin, 4.39 mg/g of myricetin and 2.58 mg/g of catechin. In addition,
this hexane fraction greatly increased both cell growth and outgrowth of the neurite, and whose effects were three times higher
than those of the other fractions. The length of the neurites was measured as ca. 110 μm in adding 50 μg/mL of the hexane
fraction, which was about the same as the case of adding 50 ng/mL of NGF as a positive control. This result indicates that
the differentiation of PC12 cells by the addition of the hexane fraction was comparable to the case of adding NGF. The hexane
fraction was also determined to prevent apoptosis of PC12 cells by suppressing DNA fragmentation. It is interesting that the
mixture of three major flavonoids, quercetin, myricetin and catechin showed stronger activity on, both PC12 cell growth and
neuritis outgrowth, than when adding each flavonoid alone. We believe this was due to the synergistic effects of the three
flavonoids. The activities of these flavonoids from Angelica gigas Nakai are reported for the first time in this study. 相似文献
3.
Patrick H. Brown Steven A. Weinbaum Geno A. Picchioni 《Trees - Structure and Function》1995,9(3):158-164
The influence of alternate bearing on nutrient utilization and total tree nutrient content was investigated in mature pistachio
(Pistacia vera L. cv Kerman trees). Removal of N, P and Zn in fruit and abscised leaves of cropping (‘on’) trees averaged 5, 6, and 2 times,
respectively, the removal in abscised leaflets of the non-fruiting, ‘off’ year trees. One hundred and thirty-five kg N, 131
kg K, 86 kg Ca, 39 kg Mg and 18 kg P per hectare were removed in fruits and abscised leaves in ‘on’ year trees. Tree nutrient
contents and, presumably, the size of nutrient storage pools in dormant trees varied between ‘on’ and ‘off’ years. There was
22% and 14% more N and P, respectively, in dormant trees following ‘off’ than ‘on’ years. The greater N and P accumulation
in ‘off’ year trees is depleted in support of the large fruit demand for N and P during ‘on’ years. In contrast to N and P,
there was greater K and Ca accumulation in perennial tree parts during ‘on’ years than during ‘off’ years. The greater K accumulation
in perennial tree parts and approximately 30% greater removal of K in annual organs during ‘on’ than ‘off’ years suggests
that K uptake could be 4 times higher in ‘on’ year trees than in (non-cropping), ‘off’ year trees. 相似文献
4.
C.R. Vieira M.F. Marques P.R. Soares L. Matuda C.M.A. de Oliveira L. Kato C.C. da Silva L.A. Guillo 《Phytomedicine》2008,15(6-7):528-532
On a preliminary screening, relevant in vitro antiproliferative activity was observed to the crude ethanolic extract of Pterodon pubescens seed oil against the human melanoma cell line SK MEL 37. The diethyl ether fraction from crude ethanolic extract which exhibited stronger activity was submitted to fractionation by gradient elution with hexane/ethyl acetate. Subfraction A, eluted by hexane/ethyl acetate (80:20), was essentially the most active between all the assayed subfractions with an IC50 of 37 μg/ml calculated by the MTT colorimetric method. At this concentration, subfraction A caused morphological features and internucleosomal DNA fragmentation pattern of apoptosis. Through chromatographic separation, the furane diterpene 1 was isolated from this active subfraction and identified by spectral techniques. Compound 1 showed an IC50 value of 32 μM and fluorescence staining with DAPI revealed some typical nuclear changes which are characteristic of apoptosis. These findings support a role for diterpenoids vouacapan-type skeleton as a model to develop new anticancer agents. 相似文献
5.
Jeyasankar Alagarmalai Mor Grinberg Rafael Perl-Treves Victoria Soroker 《Journal of Insect Behavior》2009,22(5):375-387
This study examined the host-selection ability of the broad mite Polyphagotarsonemus latus (Banks) (Acari: Tarsonemidae). To make long-distance-shifts from one host plant patch to another, broad mites largely depend
on phoretic association with whiteflies. However, the host plants of whiteflies and broad mites are not necessarily the same.
We determined the host-preference and acceptance of free-moving and phoretic broad mites using two behavioral bioassays. We
used a choice test to monitor host selection by free-moving mites. In the case of phoretic mites, we compared their rate of
detachment from the phoretic vector Bemisia tabaci placed on leaves taken from various host plants. The suitability of the plant was further determined by monitoring mite’s
fecundity and its offspring development. We compared the mites’ responses to young and old cucumber (Cucumis sativus cv. ‘Kfir’) leaves (3rd and 8–9th leaf from the apex, respectively), and two tomato (Solanum lycopersicum cvs. ‘M82’ and ‘Moneymaker’). Free-moving mites of all stages and both sexes preferred young cucumber leaves to old cucumber leaves and preferred young
cucumber rather than young tomato leaves, demonstrating for the first time that broad mites are able to choose their host
actively. As for phoretic mated females, although eventually most of the mites abandoned the phoretic vector, the rate of
detachment from the whitefly vector was host dependent and correlated with the mites’ fitness on the particular host. In general,
host preference of phoretic female mites resembled that of the free-moving female. Cues used by mites for host selection remain
to be explored. 相似文献
6.
Dagmar Janovská Pavel Klouček Jan Urban Tomáš Vaněk Vojtěch Rada Ladislav Kokoška 《Biologia》2008,63(5):607-609
The antimicrobial activity of the dichloromethane extract from aerial parts of Leuzea carthamoides DC. was tested in vitro against 19 Staphylococcus aureus strains (ATCC 25923, CNCTC Mau 43/60, clinical isolates). The extract was fractionated by column chromatography on silica
gel into six fractions (petroleum ether, toluene, dichloromethane, ethyl acetate, methanol and water). The minimum inhibitory
concentrations (MICs) of the fractions ranged from 64 to 1024 μg/mL. An ethyl acetate fraction (EA 1) with the widest range
of activity inhibited all of the strains with MIC in the range 128–512 μg/mL. This fraction exhibited potent activity against
strains which showed associated resistance to oxacillin, ciprofloxacin and erythromycin. 相似文献
7.
In vitro and in vivo anti-allergic effects of ‘benifuuki’ green tea containing O-methylated catechin and ginger extract enhancement 总被引:1,自引:0,他引:1
‘Benifuuki’, a tea (Camellia Sinensis L.) cultivar in Japan, is rich in anti-allergic epigallocatechin-3-O-(3-O-methyl) gallate (EGCG3″Me). ‘Benifuuki’ green tea and simultaneous addition of ginger extract remarkably suppressed cytokine
(TNF-α and MIP-1α) secretion from mouse bone marrow-derived mast cells after antigen stimulation and, as expected, suppressed
delay-type allergy. After drinking ‘benifuuki’ green tea containing 43.5 mg of EGCG and 8.5 mg of EGCG3″Me, the AUC (area
under the drug concentration time curve; min μg/ml) of EGCG was 6.72 ± 2.87 and EGCG3″Me was 8.48 ± 2.54 in healthy human
volunteers. Though the dose of EGCG was 5.1 times the dose of EGCG3″Me, the AUC of EGCG3″Me was higher than that of EGCG.
A double blind clinical study on subjects with Japanese cedar pollinosis was carried out. At the 11th week after starting
the study, in the most severe cedar pollen scattering period, symptoms, i.e., blowing the nose and itching eyes, were significantly
relieved in the ‘benifuuki’ intake group compared with the placebo group, and blowing the nose, itching eyes and nasal symptom
score, and at the 11th and 13th weeks, stuffy nose, throat pain and the nasal symptom medication score were significantly
relieved in the ‘benifuuki’ containing ginger extract group compared with the placebo group. These results suggested that
over one consecutive month, drinking ‘benifuuki’ green tea was useful to reduce some of the symptoms from Japanese cedar pollinosis,
and did not affect any normal immune response in subjects with seasonal rhinitis, and the ginger extract enhanced the effect
of ‘benifuuki’ green tea. 相似文献
8.
C. M. Felland L. A. Hull B. A. Barrett A. L. Knight J. W. Jenkins P. A. Kirsch D. R. Thomson 《Entomologia Experimentalis et Applicata》1995,74(2):105-114
Mating disruption treatments for the tufted apple bud moth (TABM),Platynota idaeusalis (Walker), were tested in small plot trials in apple orchards in Pennsylvania. Treatments were evaluated by fruit injury and
by capture of male TABM in traps baited with synthetic pheromone sources or virgin females. The TABM pheromone is a two component
isomeric blend ofE-11-tetradecen-1-ol (E11-14:OH) andE-11-tetradecenyl acetate (E11-14:Ac). A 50∶50 ratio of these two components was used in standard monitoring septa and in mating
disruption treatments released from either hollow fibers (‘fiber’) or PVC tubes (‘PVC’). Other pheromone blends tested included
a 90∶10 ratio of E11-14: Ac and E11-14:OH (‘EAc’) and its reverse (‘EOH’), mixture ‘EAc’ with 30% of the Z-isomers (‘low AEc’),
and a blend similar to the preceding with 2% Z9-12:Ac (‘generic’). These other blends were released from multi tube tape (‘tape’)
or Shin-Etsu type rope (‘rope’) dispensers. Seasonal dispenser release rate in mg ha−1 h−1 was ca. 30 for the ‘rope’ dispensers, 14 for ‘PVC’ and 6 for ‘fiber’. ‘EAc-tape’ and ‘EOH-tape’ were equally effective in
reducing catches of males in traps baited with synthetic lures and in traps baited with virgin females. Both treatments also
reduced fruit injury. ‘EAc-rope’, ‘fiber’ and ‘PVC’ also were generally effective; whereas, the ‘low EAc’ and ‘generic’ treatments
reduced trap capture less than 90% and did not reduce fruit injury. Dispenser density was positively correlated with reduction
in trap capture for the ‘low EAc-rope’ and ‘genericrope’ treatments. Traps loaded with ‘fiber’ dispensers captured more male
TABM than the other treatments in non-pheromone permeated environments. Trap capture of other tortricids was reduced in pheromone
treatments. ‘EAc-rope’ and the ‘TABM’ treatments provided mean (s.e.) percent reduction in trap catch of 99.5 (0.4) and 42.9
(10.1), respectively, for the redbanded leafroller,Argyrotaenia velutinana (Walker), and 90.4 (6.8) and 90.4 (1.3), respectively, for the obliquebanded leafroller,Choristoneura rosaceana (Harris). 相似文献
9.
Identification,isolation and characterization of a CC-NBS-LRR candidate disease resistance gene family in grapevine 总被引:2,自引:0,他引:2
Andreas Kortekamp Leocir Welter Sarah Vogt Alexander Knoll Florian Schwander Reinhard Töpfer Eva Zyprian 《Molecular breeding : new strategies in plant improvement》2008,22(3):421-432
10.
Reported crystallographic data and calculated molecular models indicated that chlorophyll (Chl) a and bacteriochlorophyll (BChl) a tend to bind the fifth ligand on the side of the macrocycle where the C132-(R)-methoxycarbonyl moiety protrudes (denoting the ‘back’ side). The crystal structures of 34 photosynthetic proteins possessing
(B)Chl cofactors revealed that most of Chl a and BChl a (and b) are coordinated by any peptidyl residue (e.g., histydyl-imidazolyl group), peptidyl backbone or water from the ‘back’ side.
Almost all the cofactors that bind a water molecule as the fifth ligand in these proteins have a ‘back’ configuration. Theoretical
model calculations for methyl chlorophyllide a (MeChlid a) and methyl bacteriochlorophyllide a (MeBChlid a) bound to an imidazole molecule indicated that the ‘back’ side is energetically favored for the ligand binding. These results
are consistent with the fact that ethyl chlorophyllide a (EtChlid a) dihydrate crystal consists of the ‘back’ complex. The modeling also showed that both removal and stereochemical inverse
of the C132-methoxycarbonyl group affect the relative stability between the ‘back’ and ‘face’ complexes. The effect of the C132-moiety on the choice of the macrocycle side for the ligand binding is discussed in relation to the function of P700.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
11.
Leal F Loureiro J Rodriguez E Pais MS Santos C Pinto-Carnide O 《Plant cell reports》2006,25(9):978-985
Flow cytometry was employed to determine the ploidy level of Vitis vinifera L. somatic embryo-derived plants obtained from anther culture. Only one among the 41 analysed plants (2.4%) presented somaclonal variation (tetraploidy); the other plants were diploid. No significant differences (P≤0.05) were detected between diploid and parental field plants. No haploid or aneuploid plants were observed. The nuclear DNA content of nine V. vinifera cultivars was also estimated using flow cytometry. A non-significant variation was found among the cultivars, with DNA content ranging from 1.17 pg/2C (cv. ‘Tinta Barroca’ and ‘Viosinho’) to 1.26 pg/2C (cv. ‘Cabernet Sauvignon’). These results and previous studies on other Vitis species suggest that Vitis genome is stable with regard to nuclear DNA content. 相似文献
12.
Paul Ondo Ovono Claire Kevers Jacques Dommes 《Plant Cell, Tissue and Organ Culture》2007,91(2):107-114
Yams (Dioscorea spp) are tuber crops used as staple food in Africa because of their nutritional value. However agronomic constraints, phytosanitary
problems and the lack of good healthy planting material restrict their production. In contrast to the inefficiency of traditional
method of planting, tissue culture techniques allow to increase the multiplication and the rapid production of pathogen- free
plant material. This work was undertaken to provide farmers in African countries with healthy microplants and microtubers
as seeds. In vitro nodal segments of two varieties of local yams D. cayenensis–D. rotundata complex (cv. ‘Singo’, cv. ‘Singou’ and cv. ‘Gnidou’) were micropropagated on the modified medium of Murashige and Skoog.
The morphogenesis, the growth of microplants and microtuber formation have been found to be controlled by external factors
that act individually and synergistically. Addition of kinetin (2 mg l−1) to the culture media could reduce multiplication rate (node number) of some clones. An increase of the sucrose concentration
from 3% to 5% induced no change in the multiplication and tuberisation parameters. An important reduction of the multiplication
(shoot number, height and node number) and the tuberisation (tuber number and length) was observed with 8% sucrose. Multiplication
(shoot and node number) was increased in the presence of jasmonic acid (10 μM). JA also induced an increase of tuber number
in the absence of Kin. Multiplication of yam by in vitro growth of nodal segments is a way for rapid clonal multiplication
and could allow solving the problem of lack of seed material faced by farmers. This method could also be used for multiplication
of elite cultivars, independently of the growing season. 相似文献
13.
D. Curnoe 《Human Evolution》2001,16(3-4):169-198
Among Plio-Pleistocene hominins the East African ‘robust’ group [Australopithecus (Paranthropus) boisei sensu lato] has the largest sample. This makes it an important test case for examining within-group variability and its implications
for early hominin systematics. When using the CV to test for mixed-species samples, sexual dimorphism and diachronic variation
are important additional (confounding) sources of variability. After examining nineteen variables, five craniometric variables
in the East African ‘robust’ group are identified that have low sexual dimorphism. All are characterised by CVs from a combined
KNM-WT 17000 andA. (P.) boisei sample less than the CV of the bonobo. Diachronic variation is found to be an important source of variability for cranial
capacity. This form of variation cannot be detected in other variables studied here, but its possible presence cannot be ignored
(owing mostly to small sample sizes). It is concluded that there is insufficient evidence to refute the hypothesis that all
East African ‘robust’ fossils belong toA. (P.) boisei (Walker and Leakey, 1988). 相似文献
14.
I. Billy Annan George A. Schaefers Ward M. Tingey W. F. Tjallingii 《Journal of Insect Behavior》1997,10(5):603-618
Electrical penetration graph recordings using direct current (DC-EPGs) were used to analyze aspects of the probing behavior
of cowpea aphid,Aphis craccivora Koch, on intact plants and on hexane, ethyl acetate, and methanol extracts of leaves of aphid-resistant (ICV-12) and aphid-susceptible
(ICV-1) cultivars of cowpeaVigna unguiculata (L.) Walp. In one set of experiments, recordings were done on plants with or without parafilm wrapping, or on plants painted
with raw leaf juice and extracts of the two cultivars. In another study, recordings were done on leaf extracts homogenized
in water or in 0.5M sucrose solution and then placed in parafilm membrane sachets. Electrodes were inserted into soil mix for the experiments
on potted plants or into extract fractions and raw juice for the membrane feeding experiments on leaf extracts in parafilm
sachets. Waveform signals were recorded from resistance fluctuations from interactions between aphids and substrates, and
electromotive forces generated within each preparation. ICV-12 plants with or without parafilm wrapping, and ethyl acetate
extracts and raw juice of that cultivar significantly (P≤0.05) reduced stylet penetration behavior. Thus, antixenosis as manifested by disruption of aphid stylet activity on host
substrates, appeared to be a governing modality of aphid resistance in ICV-12. 相似文献
15.
This study analyzed genetic differences of 19 cultivars selected from somaclonal variants of Syngonium podophyllum Schott along with their parents as well as seven additional Syngonium species and six other aroids using amplified fragment length polymorphism (AFLP) markers generated by 12 primer sets. Among the 19 somaclonal cultivars, ‘Pink Allusion’ was selected from ‘White Butterfly’. Tissue culture of ‘Pink Allusion’ through organogenesis resulted in the development of 13 additional cultivars. Self-pollination of ‘Pink Allusion’ obtained a cultivar, ‘Regina Red Allusion’, and tissue culture propagation of ‘Regina Red Allusion’ led to the release of five other cultivars. The 12 primer sets generated a total of 1,583 scorable fragments from all accessions, of which 1,284 were polymorphic (81.9%). The percentages of polymorphic fragments within ‘White Butterfly’ and ‘Regina Red Allusion’ groups, however, were only 1.2% and 0.4%, respectively. Jaccard's similarity coefficients among somaclonal cultivars derived from ‘White Butterfly’ and ‘Regina Red Allusion’, on average, were 0.98 and 0.99, respectively. Seven out of the 15 cultivars from the ‘White Butterfly’ group and three out of six from the ‘Regina Red Allusion’ group were clearly distinguished by AFLP analysis as unique fragments were associated with respective cultivars. The unsuccessful attempt to distinguish the remaining eight cultivars from the ‘White Butterfly’ group and three from the ‘Regina Red Allusion’ group was not attributed to experimental errors or the number of primer sets used; rather it is hypothesized to be caused by DNA methylation and/or some rare mutations. This study also calls for increased genetic diversity of cultivated Syngonium as they are largely derived from somaclonal variants. 相似文献
16.
Experiments were conducted to quantify parasitism of Colorado potato beetle,Leptinotarsa decemlineata (Say), by the egg parasitoid,Edovum puttleri Grissell, on 3 different cultivars of eggplant,Solanum melongena L. Levels of parasitism were higher (P<0.05) on ‘Black Pride’ than on other cultivars. The percentage of egg masses that
were parasitized was 1.2-fold higher (P<0.05) on ‘Black Pride’ than on ‘Harris Special’ and ‘White’. The number of eggs per
mass that were parasitized was 1.3- and 1.4- fold greater (P<0.05) on ‘Black Pride’ than on ‘Harris Special’ and ‘White’,
respectively. The percentage of eggs that were parasitized per mass and percentage of emerged adult parasitoids did not differ
(P>0.05) among cultivars; between 2.1- to 2.6- fold more females than males emerged from eggs on all cultivars during the
growing season.Edovum puttleri suppressed the 2nd generation ofL. decemlineata on ‘Black Pride’ and ‘Harris Special’, but did not suppress populations on ‘White’.
相似文献
17.
Summary Anthers and ovaries of six grapevine cultivars (three Vitis vinifera L., two V × Labruscana L. H. Bailey, and one complex hybrid) were extracted from flower buds over 2 yr and cultured on three media reported to promote
somatic embryogenesis in Vitis tissues. The highest percent embryogenesis from the hybrid ‘Chancellor’ and V. vinifera ‘Chardonnay’, ‘Merlot’, and ‘Pinot Noir’ occurred on medium C [Nitsch and Nitsch, 1969, basal medium with 3.0% (w/v) sucrose,
0.01% (w/v) inositol. 0.3% (w/v) Phytagel, 2.5 μM 2.4-dichlorophenoxyacetic acid, 2.5μM β-naphthoxyacetic acid, 5.0μM N-(2-chloro-4-pyridyl)-N′-phenylurea, and 0.05% (w/v) glutamine]. Regardless of the media, the labrusca cultivars ‘Concord’ and ‘Niagara’ produced
soft non-embryogenic callus that was sometimes mixed with well-developed somatic embryos. Nine vinifera genotypes were further
tested for several different years on medium C. Embryogenic cultures suitable for transformation were obtained from all genotypes
in more than 1 yr. The average percent embryogenesis from ovaries was 7-fold higher than from anthers. There was significant
annual variation in percent embryogenesis, demonstrating the need for media comparisons to be replicated for more than one
season. Suspension cultures suitable for use in genetic transformation were initiated from ‘Chardonnay’, ‘Merlot,’ and ‘Pinot
Noir’ pro-embryogenic masses. ‘Chardonnay’ suspension cultures plated and grown under conditions developed for recovery of
plants after biolistic transformation yielded approximately 500 non-transformed embryos per plate after 4 mo. of culture,
with 68.6% of the embryos converting to plants. This is the first reported protocol for embryogenesis from ‘Concord,’ ‘Cabernet
Franc,’ and ‘Pinot Noir’ grapevines. 相似文献
18.
【背景】人参菌核病是人参的主要病害之一,严重影响人参的产量。【目的】探索白花蒲公英内生菌(Endomelanconiopsis microspora)发酵产物乙酸乙酯提取物对人参核盘菌的抑制机理。【方法】采用人参核盘菌菌丝生长和孢子萌发试验测定抑制效果;采用显微镜观察菌丝形态变化,通过电导率和核酸含量的变化测定细胞膜通透性,通过丙二醛(malondialdehyde,MDA)含量和超氧化物歧化酶(superoxide dismutase,SOD)、过氧化物酶(peroxidase,POD)和过氧化氢酶(catalase,CAT)活力的变化测定膜脂过氧化程度。【结果】内生菌E. microspora发酵产物乙酸乙酯提取物能显著抑制人参核盘菌菌丝生长,最小抑菌浓度为3.75 mg/mL,培养6 d后抑制率为76.22%。该提取物能显著抑制人参核盘菌孢子萌发,15.00 mg/mL时抑制效果最好,抑制率达90.69%。提取物影响菌丝形态,增加人参核盘菌细胞膜通透性,造成菌丝内含物外渗,7.50 mg/mL处理10 h后电导率和核酸含量分别比对照组增加30.11%和62.85%。同时提取物显著增加人参核盘菌MDA含量和SOD、POD、CAT活力,7.50 mg/mL处理组呈现先上升后下降的变化趋势,并在12 h时达到最高值。【结论】内生菌E. microspora发酵产物乙酸乙酯提取物通过改变人参核盘菌细胞膜通透性,加剧膜脂过氧化,破坏细胞膜完整性,导致细胞内含物流失,显著抑制孢子萌发和菌丝生长。 相似文献
19.
M. Pavunraj M. Gabriel Pulraj S. Selva Kumar M.R.K. Rao 《Archives Of Phytopathology And Plant Protection》2013,46(17):2066-2075
Different organic solvent crude extracts from the leaves of Alangium salviifolium (L.F.) Wangerin, were tested for their feeding deterrence, larvicidal activity and protein concentrations on the fourth instar larvae of Spodoptera litura L. under laboratory conditions. Treatments were given through two different host plant leaves such as brinjal and castor. The bioassay was carried out at different concentrations viz., 0.625, 1.25, 2.5 and 5%. The maximum antifeedant activity in brinjal (52.0%) and castor (29.97%) leaf discs was recorded in ethyl acetate extract as compared with hexane and chloroform extracts at 5% concentration. The result of larvicidal activity revealed that the maximum larval mortality was registered in brinjal leaves (65.81%) and castor with (57.48%) in ethyl acetate extract as compared to hexane and chloroform extracts at 5% concentration. The ethyl acetate extract of A. salviifolium contained alkaloids, diterpenoids, and saponins. The treatment also reduced haemolymph protein concentration after 48 h. 相似文献
20.
Betelvine (Piper betle L., family Piperaceae) is an important, traditional and widely cultivated crop of India. The cultivators and consumers recognize
more than 100 cultivars (landraces) based on regional and organoleptic considerations, while in terms of phytochemical constituents
only five groups have been identified for all the landraces. Since betelvine is an obligate vegetatively propagated species,
genomic changes, if any, may have become ‘fixed’ in the landraces. We carried out random amplified polymorphic DNA (RAPD)
analysis in several landraces considered in four groups, namely, ‘Kapoori’, ‘Bangla’, ‘Sanchi’ and ‘Others’ in order to ascertain their genetic diversity. On the basis of the data from eleven RAPD primers, we distinguished genetic
variation within and among the four groups of landraces. The results indicate the’Kapoori’ group is the most diverse. The neighbour joining (NJ) tree after a bootstrap (500 replicate) test of robustness clearly shows
the four groups to be well separated. Interestingly, all known male or female betelvine landraces have separated in the NJ
tree indicating an apparent gender-based distinction among the betelvines. 相似文献