细化搜索
结果 1-10 的 1,819
Impact of adjuvants on bentazon efficacy on selected broadleaf weeds 全文
2009
Abouziena, Hussein Fawzy H. | Sharma, Shiv D. | Singh, Megh
Tank-mix adjuvants can increase the efficacy of herbicides. Therefore, the effects of different rates of bentazon alone or tank-mixed with ammonium sulfate, non-ionic (0.25% Induce) or organosilicone (0.1% Kinetic) adjuvants were investigated on cocklebur (Xanthium strumarium), black nightshade (Solanium nigrum), velvetleaf (Abutilon theophrasti), and stranglervine (Morrenia odorata) under greenhouse condition. There were variations in susceptibility of the four weed species to bentazon-adjuvants tank-mixture treatments. Black nightshade control never exceeded 55% with all bentazan treatments rates from 0.84 to 2.24kg ha^-^1 with or without the adjuvants. While cocklebur was completely controlled with the application of bentazon at 1.12kg ha^-^1, or with bentazon at 0.84kg ha^-^1 plus one of the three adjuvants, with insignificant differences between adjuvants. The limited factor of controlling velvetleaf and stranglervine is the bentazon rate. Complete foliar death (98-100%) of velvetleaf and stranglervine was with bentazon at 1.68kg ha^-^1 alone or with Induce or Kinetic adjuvant. The results suggested that black nightshade was difficult-to-control weed, while cocklebur was susceptibility to bentazon at lowest rate (0.84kg ha^-^1) plus adjuvant. Mixing adjuvant with bentazon generally enhanced common cocklebur and black nightshade control, while addition of adjuvant to bentazon at all rates for controlling stranglervine did not cause any significant difference.
显示更多 [+] 显示较少 [-]Study on efficacy of different fungicides on leaf spot of cabbage
2009
Lakho, A.A.
An investigation was undertaken both In-vitro as well as In-vivo to assess the efficacy of various fungicides on leaf spot of cabbage caused by Alternaria brassicae. Symptoms of disease shows that the spots were sphagenous, the entire leaf became brown and the spots were of lighter shade than the surrounding parts. The hyphye measured from 1-4.5 micron in diameter and conidiophores measured 3-10 micron. During the studies carried out In-vivo, to see the development of fungus under various fungicide treatments. It was observed that Ridomil remained on top among various fungicides in reducing Alternaria brassicae population, although all fungicides reduced disease as compared to control but remained at par with Ridomil. On the basis of present investigation it may be concluded that Ridomil was the more effective fungicide in control leaf spot of cabbage.
显示更多 [+] 显示较少 [-]Improved efficacy of tetracycline by acaciasides on Dirofilaria immitis 全文
2009
Datta, S. | Maitra, S. | Gayen, P. | Sinha Babu, S. P.
The discovery of Wolbachia, a bacterial endosymbiont that occurs in the filarial parasite and its sensitivity to tetracycline, has fostered a new initiative in the development of suitable antifilarial drugs. The present study is an attempt to investigate whether adding acaciasides (saponins from Acacia auriculiformis) to the standard dose of tetracycline would further improve the efficacy of tetracycline treatment against Dirofilaria immitis microfilariae in vivo. Treatment of microfilaremic adult dogs (body weight range 8-12 kg) with tetracycline at 10 mg/kg/day for 40 days resulted in 72% and 83% reduction in mf count on days 15 and 30, respectively, and the maximum reduction in mf count (91%) was achieved on day 75 post-treatment. However, treatment with tetracycline (10 mg/kg/day for 40 days) followed by acaciasides (10 mg/kg/day for 7 days) resulted in almost 100% clearance of mf at a faster rate on day 45 post-treatment and ensured long-term (until 4 months post-treatment) protection against microfilaremia. Data from polymerase chain reaction analysis reveals that compared to untreated dogs, in treated dogs, there was marked reduction in Wolbachia specific wsp markers in fast depleting mf population. The present data indicate that prior tetracycline treatment enhances microfilaricidal activity of saponins. This effect may be additive or synergistic as the worms are weakened by Wolbachia depletion, and these weakened microfilariae are possibly killed by the saponins.
显示更多 [+] 显示较少 [-]Efficacy of bio-pesticides against jassid on okra crop
2009
Laghari, A.A.
A field experiment was carried out to evaluate the efficacy of bio-pesticides against jassid on okra seed was sown on ridges keeping a ridge to ridge distance of 45 cm after completion of germination seedlings were thinned and a plant to plant distance of 22.5 cm was maintained. There were twenty plots, each plot measuring an area of 6x3.5 meter. Following bio-pesticides were applied against thrice jassid at economic threshold level. Pre-treatment population of jassid was recorded one day before spray from randomized selected 5 plants from each treatment. While post treatment jassid count was made after 24, 48, 72 hours one and two weeks of spray. It was observed that during 1st spray all the four bio-pesticides reduce the population of jassid as compared to untreated control. However, the reduction percentage varied significantly between the products after 24, 48, 72 hours, one and two weeks of their application.
显示更多 [+] 显示较少 [-]Efficacy of new insecticides against pod borer on soybean.
2009
Keyhaniyan, A`li Akbar | Barari, Hassan | Qadiri Rad, Sa`id | Sharifi Ziveh, Parviz | A`ttaran, Mohammad Reza | Espahbodi Niya, A`bd Ol-Ali | Mohammadi Pur, A`li | Ahmadi, Mohammad | Saqqaei Niya, A`raz Mohammad | Heydar Zadeh, E. | Panj A`li Zadeh, Teymur
The soybean pod borer, Helicoverpa armigera is one the most important pest's of soybean in Iran. In recent years, the chemical control of this pest has become difficult because of less effect of the common insecticides. Therefore, the efficacy of the common and new insecticides from Sumitomo and Keshtgar companies on the pest larvae were tested in a Randomized Complete Blocks Design with six treatments and a control (only water) in four replications in three provinces, Ardebil, Golestan and Mazandaran during 2007-2008.The treatments were Sevin (carbaryl) (3kg/ha), Avaunt (indoxacarb)SC15 (250ml/ha), EC15 (250ml/ha),Pridalyl (sumipleo) EC50 (200ml/ha), Pridalyl (sumipleo)EC50(150ml/ha) and Tracer(spinosad) SC24 (150ml/ha). Insecticide application was carried out when the most pest eggs were hatched and very young larvae started feeding on terminal and apical buds and pods. Sampling and counting live larvae was done a day before and 1, 3, 7, and 10 days after treatment by randomly selected 10 plants from four middle rows in each replication. Data were analyzed with SAS software, the means were compared using Duncan and the larval mortality was calculated by Henderson- Tilton formula. The results of seven and ten days after insecticide application showed a significant difference among treatments at 1% and 5% level. Indoxacarb SC15 (250ml/ha.) and Carbaryl Avaunt EC15(250ml/ha) were both the most effective treatments and placed in the first group (A), Indoxacarb EC15(250ml/ha), Pridalyl EC50 (200ml/ha) and Pridalyl EC50 (150ml/ha) in second group (B) , wile Tracer SC24 (150ml/ha) placed in third group.
显示更多 [+] 显示较少 [-]Efficacy of Rheum officinale liquid formulation on cucumber powdery mildew 全文
2009
Yang, Xiaojun | Ma, Xingxia | Yang, Lijun | Yu, Dazhao | Qian, Yixin | Ni, Hanwen
Rheum officinale liquid formulation, the ethanol extract from roots of R. officinale Baill., formulated as physcion 5gl^-^1 aqueous solution (AS), has been commercialized in China for controlling cucumber powdery mildew (Podosphaera xanthii (Castagne) U. Braun '' Shishkoff). The efficacy of the product was evaluated in pot tests under controlled conditions and in open and protected fields in China over 2 years. In most trials, the efficacy reached above 80% at the rates of 10-50mga.il^-^1 water after three applications and at the rates of 20-50mga.il^-^1 water after two applications. The cucumber fruit yield in the product treatment was as many or more as triadimefon treatment, and over 53.1% compared to the untreated control. These results showed that Chinese rhubarb extract could be an effective alternative plant protecting agent in the integrated and biological management of cucumber powdery mildew.
显示更多 [+] 显示较少 [-]Efficacy of myrtle oil against Salmonella Typhimurium on fresh produce 全文
2009
Gündüz, Gülten Tiryaki | Gönül, Şahika Aktuğ | Karapinar, Mehmet
The antimicrobial activity of myrtle leaves (Myrtus communis) oil was tested against the nalidixic acid resistant strain of Salmonella Typhimurium ATCC 13311. An inoculum (100 μl, ca.10⁸ cfu/ml) was deposited on the skin of whole tomatoes and 10 g of shredded iceberg lettuce, dried for 2 h at 22 °C and held for 22 h at 4 °C before treatments. Inoculated iceberg lettuce (3.51-3.99 log cfu/g) and tomatoes (3.47-4.86 log cfu/tomato) were treated with three different washing procedures for 5, 10, 15 and 20 min; washing with sterile distilled water (control), washing with three different concentrations of myrtle leaves oil and the last treatment was a combination of washing with myrtle leaves oil and then rinsing in sterile distilled water for 1 min. Washing with myrtle leaves oil with or without rinsing procedures caused significant reduction in S. Typhimurium population compared with the control after treatment for four different times (p <0.05). There is no significant difference between washing times in reduction of S. Typhimurium (p >0.05). The maximum logarithmic reductions of 1.66 cfu/g-1.89 cfu/tomato were respectively obtained on iceberg lettuce and tomatoes treated with 1000 ppm myrtle leaves oil without any rinsing treatment. The results suggest that the use of myrtle leaves oil is an innovative and useful tool as an alternative to the use of chlorine or other synthetic disinfectants in fruits and vegetables, especially for organic products.
显示更多 [+] 显示较少 [-]Leaves coverage of spray liquid and influence on herbicide efficacy 全文
2009
Martin Prokop
The effect of spray liquid leaves coverage on efficacy of herbicides was investigated. Five nozzles sizes were used to reach different percentage coverage. The effect of leaves coverage on Elytrigia repens (L.) Desv. was evaluated using systemic herbicide (clethodim 240 g / l + surfactant) and the effect of leaves coverage on Chenopodium album L. and Galium aparine L. was evaluated using contact herbicides (bentazone 600 g / l and the mixture of bentazone 480 g / l + activator 150 g / l). No significant differences of the efficacy were observed between different percentages of leaves coverage in case of systemic herbicides. Vice versa the efficacy significantly increased with higher percentage of leaves coverage in case of contact herbicides.
显示更多 [+] 显示较少 [-]Efficacy of 5-week doxycycline treatment on adult Onchocerca volvulus 全文
2009
Hoerauf, Achim | Specht, Sabine | Marfo-Debrekyei, Yeboah | Büttner, Marcelle | Debrah, Alexander Yaw | Mand, Sabine | Batsa, Linda | Brattig, Norbert | Konadu, Peter | Bandi, Claudio | Fimmers, Rolf | Adjei, Ohene | Büttner, Dietrich W.
The effects of 5-week doxycycline treatment on the depletion of Wolbachia endobacteria from Onchocerca volvulus, on the interruption of embryogenesis and on microfilariae production, and with regard to macrofilaricidal activity were studied. In 2003, in an endemic area in Ghana, 22 onchocerciasis patients received 100 mg/day doxycycline for 5 weeks. Two years after the start of the study, 20 treated and ten untreated patients were nodulectomized and skin microfilariae were counted. The onchocercomas were examined by immunohistology for the presence of Wolbachia, embryogenesis, and vitality of adult filariae. The latter two parameters were further assessed by alternating logistic regression analysis, taking into account the dependency of worms and nodules in patients. Doxycycline resulted in depletion of Wolbachia and in complete interruption of embryogenesis in all worms that were assumed to have been present during treatment. In the treated patients, only 51% of the female worms were alive, compared to 84% in the untreated patients, indicating a moderate but distinct macrofilaricidal activity of doxycycline at this dose. It is concluded that, in areas with ongoing transmission, doxycycline cannot replace regular ivermectin mass treatment because new infections would require repeated rounds of doxycycline. However, doxycycline can be used for the treatment of individuals outside transmission areas, in foci where ivermectin resistance may occur, and in countries where onchocerciasis and loiasis are co-endemic.
显示更多 [+] 显示较少 [-]Efficacy of prescribed grazing depends on timing intensity and frequency 全文
2009
Rinella, Matthew J. | Hileman, Benjamin J.
1. Exotic weeds and woody plants have invaded many grasslands, and prescribed grazing is one management technique used to combat these plants. Prescribed grazing entails introducing livestock such as sheep or goats that eat unwanted plants. It sometimes has desirable effects, but inconsistencies among study results discourage widespread use. Detailed studies that manipulate grazing timings, intensities and frequencies may explain inconsistencies among previous studies and identify effective weed control strategies. 2. We studied Euphorbia esula, an invasive forb avoided by cattle but eaten by sheep. We used simulated grazing (clipping) to estimate E. esula and resident plant responses to cattle and sheep grazing protocols. 3. Depending on timing, intensity and frequency, simulated grazing either: (i) did not dramatically affect the invader and/or resident species, (ii) increased the invader and decreased resident species or (iii) decreased the invader and increased resident species. These disparate results illustrate that successful prescribed grazing entails more than simply introducing animals that eat unwanted plants. 4. Our most promising finding was that removing small quantities of invader and resident species' biomass at early growth stages reduced the invader and increased resident species over time. Defoliating more intensively at later growth stages often gave the opposite response. Forage availability is lowest in spring, so a given landmass can be prescription grazed with fewer animals (or in less time) in spring compared with later in the year. 5. Synthesis and applications. Our study illustrates that responses to prescribed grazing depend heavily on the specifics of the grazing regime. Our results show that some grazing strategies have the potential to exacerbate weed problems, while other strategies help to control the invader and restore desired species. In the case of E. esula, very light prescribed grazing can be beneficial when conducted early in the growing season.
显示更多 [+] 显示较少 [-]