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Mechanism of action of Gliocladium virens on Alternaria helianthi  [cached]
R. ANITHA and K. MURUGESAN
Indian Phytopathology , 2012,
Abstract: The light and scanning electron microscopic studies on the interaction between Alternaria helianthi, causal agent of blight of sunflower and the antagonist Gliocladium virens revealed that there was no hyphal envelopment and physical coiling between the hyphae of the mycoparasite and its host.
INFLUENCE OF NUTRITION MEDIA ON FORMATION OF PERITHECIA OF Diaporthe helianthi (Phomopsis helianthi) Munt.-Cvet.
Karolina Vrande?i?,Dra?enka Jurkovi?,Jasenka ?osi?
Poljoprivreda (Osijek) , 2009,
Abstract: Diaporthe helianthi isolates were grown on various media (water agar with various plant tissues, potatoes dextrose agar, malt agar and V-8 juice agar) with the aim to examine media influence on the development of reproductive structures. Isolates were distinguished by whether they form teleomorphic stage or not, and by the number of formed pycnidia and perithecia. Water agar with various plant parts was proved as a suitable media for perithecia production.
Effect of Surfactants on Bioherbicidal Activity of Alternaria helianthi on Multiple-Seeded Cocklebur
D. Sanyal,P.C. Bhowmik,H.K. Abbas
Plant Pathology Journal , 2008,
Abstract: Multiple-seeded cocklebur (Xanthium strumarium L.) is a biotype which has different morphology and higher seedling production ability than common cocklebur. Greenhouse studies were conducted to investigate the bioherbicidal activity of Alternaria helianthi (Hansf.) Tubaki and Nishih. on multiple-seeded cocklebur as affected by various rates of Tenkoz COC (crop oil concentrate), Activator 90 (non-ionic surfactant), BAS 9050 0 S (methylated oil), Silwet L-77 (organosilicone surfactant) and Top film (natural based surfactant). Taking X as the recommended rate for each surfactant, 0-X, -X, -X, X and 2-X rates were used for each of the surfactants. Surfactants were added to the conidial suspension of A. helianthi. Each surfactant rate was also applied with sterile water without any A. helianthi spore. Treated plants were kept in the dew chamber for 6 h before transferring to the greenhouse. At the end of the experiment (two weeks after treatment), plant shoots were clipped at the soil surface and the fresh weights were determined. Alternaria helianthi resulted in significant reduction in fresh weight of multiple-seeded cocklebur as compared to the plants treated without the fungus. Among five surfactants, Activator 90 and Silwet L-77 had significant effects on the bioherbicidal activity of A. helianthi in reducing fresh weight of multiple-seeded cocklebur. Fresh weight decreased with increase in surfactant rates. Our data demonstrate that A. helianthi control multiple-seeded cocklebur more with higher rates of Activator 90 and Silwet L-77 .
A new species of Uroleucon (Hemiptera: Aphididae) on Madia (Asteraceae) in Chile
Delfino, Miguel A.;Gonzáles, Wilfredo L.;
Neotropical Entomology , 2005, DOI: 10.1590/S1519-566X2005000200010
Abstract: uroleucon is one of very few aphid genera that have species indigenous to south america. a new species of aphid from chile is described and illustrated, uroleucon eumadiae sp. nov., living on the two south american species of the genus madia (asteraceae): m. sativa mol. and m. chilensis (nutt.) reiche. morphological characters are discussed and the characters by which this aphid species may be distinguished from related ones are given. the long, hairy last rostral segment of the new species suggests strongly a feeding adaptation, and parallels that of a north american madia-feeding species in the same genus which is not, however, closely related.
Effects of Flos carthami on CYP2D6 and on the Pharmacokinetics of Metoprolol in Rats
Gaofeng Liu,Yan Liu,Rui Liu,Feng Dong,Zhiren Zhang
Evidence-Based Complementary and Alternative Medicine , 2011, DOI: 10.1155/2011/207076
Abstract: Flos carthami is a traditional Chinese herbal medicine. Clinically, the Flos carthami Injection has been used concomitantly with other Western drugs and may be used concomitantly with β-blockers, such as metoprolol, to treat cerebrovascular and coronary heart diseases, in China. Metoprolol is a CYP2D6 substrate and is predominantly metabolized by this isozyme. However, we do not know whether there is an effect of Flos carthami on CYP2D6 and the consequences of such an effect. Concern is raised regarding the possible herb-drug interaction. In this report, the effects of Flos carthami on the activity of CYP2D6 in vivo and in vitro and on the pharmacokinetics of metoprolol, in rats, are investigated. To assess the inhibitory potency of Flos carthami, the concentration associated with 50% inhibition (IC50) of dextromethorphan metabolism was determined based on the concentration-inhibition curves. The inhibitory effect of Flos carthami on CYP2D6 was also compared with cimetidine in vitro. Flos carthami could significantly inhibit CYP2D6 in rats both in vitro and in vivo (<.05) and could slow down the metabolic rate of metoprolol as suggested by prolonged t1/2 (67.45%), by increased max (74.51%) and AUC0−∞ (76.89%). These results suggest that CYP2D6 is a risk factor when Flos carthami is administered concomitantly with metoprolol or other CYP2D6 substrates.
Patogenicidade de Alternaria helianthi (Hansf.) e Alternaria zinniae (Pape) ao girassol a partir de sementes
Salustiano, Maria Eloísa;Machado, José da Cruz;Pittis, Janice Elaine;
Revista Brasileira de Sementes , 2005, DOI: 10.1590/S0101-31222005000100017
Abstract: the effects of alternaria helianthi and alternaria zinniae on the initial development of the sunflower were investigated under controlled conditions from inoculated seeds and 10 day old plants. inoculated plants with a. helianthi spore suspension produced a high index of disease with reduction in stand, fresh weight and plant height. similar results were obtained in the assay on inoculation of seeds and sunflower plants with alternaria zinniae. the high index of this disease also induced the reduction of stand, fresh weight and plant height.
Multispectral Imaging for Authenticity Identification and Quality Evaluation of Flos carthami  [PDF]
Cuiying Hu, Qingxia Meng, Ji Ma, Qichang Pang, Jing Zhao
Optics and Photonics Journal (OPJ) , 2013, DOI: 10.4236/opj.2013.33037
Abstract:

The identification and quality evaluation of Flos carthami were studied using tunable liquid spectral imaging instrument, to discuss the application range and advantages of spectral imaging technology in Chinese medicine identification and quality control field. The Flos carthami was indentified by extracting the normalized characteristic spectral curves of Flos carthami, Crocus sativus and Dendranthema morifolium, which were standard samples supplied by National Institute for Drug Control. The qualities of Flos carthamies collecting from different pharmacies were evaluated by extracting their normalized characteristic spectral curves. The imaging spectrum testing system was designed independently. The spectral resolution was 5 nm, and the spectral range was from 400 nm to 680 nm. The results showed that the normalized characteristic spectral curve of Flos carthami was significantly different from those of Crocus sativus and Dendranthema

Collective Defense of Aphis nerii and Uroleucon hypochoeridis (Homoptera, Aphididae) against Natural Enemies  [PDF]
Manfred Hartbauer
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0010417
Abstract: The prevalent way aphids accomplish colony defense against natural enemies is a mutualistic relationship with ants or the occurrence of a specialised soldier caste typcial for eusocial aphids, or even both. Despite a group-living life style of those aphid species lacking these defense lines, communal defense against natural predators has not yet been observed there. Individuals of Aphis nerii (Oleander aphid) and Uroleucon hypochoeridis, an aphid species feeding on Hypochoeris radicata (hairy cat's ear), show a behavioral response to visual stimulation in the form of spinning or twitching, which is often accompanied by coordinated kicks executed with hind legs. Interestingly, this behaviour is highly synchronized among members of a colony and repetitive visual stimulation caused strong habituation. Observations of natural aphid colonies revealed that a collective twitching and kicking response (CTKR) was frequently evoked during oviposition attempts of the parasitoid wasp Aphidius colemani and during attacks of aphidophagous larvae. CTKR effectively interrupted oviposition attempts of this parasitoid wasp and even repelled this parasitoid from colonies after evoking consecutive CTKRs. In contrast, solitary feeding A. nerii individuals were not able to successfully repel this parasitoid wasp. In addition, CTKR was also evoked through gentle substrate vibrations. Laser vibrometry of the substrate revealed twitching-associated vibrations that form a train of sharp acceleration peaks in the course of a CTKR. This suggests that visual signals in combination with twitching-related substrate vibrations may play an important role in synchronising defense among members of a colony. In both aphid species collective defense in encounters with different natural enemies was executed in a stereotypical way and was similar to CTKR evoked through visual stimulation. This cooperative defense behavior provides an example of a surprising sociality that can be found in some aphid species that are not expected to be social at all.
Biological aspects and life table of Uroleucon ambrosiae (Thomas, 1878) as a function of temperature
Auad, Alexander Machado;Moraes, Jair Campos de;
Scientia Agricola , 2003, DOI: 10.1590/S0103-90162003000400008
Abstract: the aphid uroleucon ambrosiae (thomas) is considered a pest of hidroponically-grown lettuce, but basic and applied information on its control are scarce in brazil. the aim of this study was to determine the effect of different temperatures on biological aspects and life history of u. ambrosiae (thomas) developing on hydroponic lettuce (lactuca sativa l.) crop. newly emerged nymphs were placed on 4-cm discs of hydroponic lettuce, var. ver?nica, which were maintained on 5-cm petri dishes, at temperatures of 15, 20 and 25oc and 14 h photophase, and inside a greenhouse, within micro-cages at room temperature. the duration of development in all nymphal stages varied inversely to temperature. nymphs maintained at 20oc and 25oc, had similar development period. however, at fluctuating greenhouse temperatures (daily mean = 21oc), different results were obtained, which was also true for the pre-reproductive, reproductive and post-reproductive periods. daily and total fertilities at 20oc were better in comparison to the other treatments. the highest mortality rate of aphids occurred under greenhouse conditions. the production of 1.28 nymphs per female per day, the time needed for the population to double in size (td=2.77days), and the intrinsic rate of population increase (rm=0.25), were similar for in insects maintained at 20 and 25oc. on the other hand, time interval between generations (t) and the net reproductive rate (ro) were higher at 20oc. in the greenhouse, even though t was similar to laboratory conditions at 20 and 25oc, the r0, rm and l parameters were lower and td was higher. based on biological aspects, fertility and life expectancy tables, constant temperature of 20oc is the most suitable for u. ambrosiae.
Biological aspects and life table of Uroleucon ambrosiae (Thomas, 1878) as a function of temperature  [cached]
Auad Alexander Machado,Moraes Jair Campos de
Scientia Agricola , 2003,
Abstract: The aphid Uroleucon ambrosiae (Thomas) is considered a pest of hidroponically-grown lettuce, but basic and applied information on its control are scarce in Brazil. The aim of this study was to determine the effect of different temperatures on biological aspects and life history of U. ambrosiae (Thomas) developing on hydroponic lettuce (Lactuca sativa L.) crop. Newly emerged nymphs were placed on 4-cm discs of hydroponic lettuce, var. Ver nica, which were maintained on 5-cm Petri dishes, at temperatures of 15, 20 and 25oC and 14 h photophase, and inside a greenhouse, within micro-cages at room temperature. The duration of development in all nymphal stages varied inversely to temperature. Nymphs maintained at 20oC and 25oC, had similar development period. However, at fluctuating greenhouse temperatures (daily mean = 21oC), different results were obtained, which was also true for the pre-reproductive, reproductive and post-reproductive periods. Daily and total fertilities at 20oC were better in comparison to the other treatments. The highest mortality rate of aphids occurred under greenhouse conditions. The production of 1.28 nymphs per female per day, the time needed for the population to double in size (TD=2.77days), and the intrinsic rate of population increase (r m=0.25), were similar for in insects maintained at 20 and 25oC. On the other hand, time interval between generations (T) and the net reproductive rate (Ro) were higher at 20oC. In the greenhouse, even though T was similar to laboratory conditions at 20 and 25oC, the R0, r m and l parameters were lower and TD was higher. Based on biological aspects, fertility and life expectancy tables, constant temperature of 20oC is the most suitable for U. ambrosiae.
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