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Mycorrhizal efficacy of trifoliate orange seedlings on alleviating temperature stress Texto completo
2011
Q.S. Wu
Citrus plants often suffer from temperature stress, which seriously inhibits tree growth and even results in tree death. The present experiment was conducted to evaluate the effects of Glomus mosseae on growth, root morphology, superoxide dismutase (SOD) and catalase (CAT) activities, and soluble protein content of trifoliate orange (Poncirus trifoliata) seedlings at low (15°C), optimum (25°C) and high (35°C) temperatures. Sixty-eight days after temperature stresses, mycorrhizal colonization and number of both entry points and vesicles were significantly inhibited by low or high temperature. Mycorrhizal seedlings recorded significantly higher growth characteristics than non-mycorrhizal seedlings at both optimum and high temperatures, but the beneficial effects were almost lost at low temperature. Generally, mycorrhizal seedlings presented notably higher root traits (projected area, surface area, number of forks and volume) than non-mycorrhizal seedlings regardless of temperature levels. Mycorrhizal colonization significantly increased SOD and CAT activities and soluble protein content at high temperature, increased only SOD activity at optimum temperature, and decreased only soluble protein content at low temperature. It suggests that mycorrhizal alleviation of temperature stress in trifoliate orange seedlings was at high temperature, but the alleviation was obviously weakened at low temperature.
Mostrar más [+] Menos [-]Efficacy of imazethapyr on weed management in soybean
2011
Meena, D.S. | Ram, Baldev | Jadon, Chaman | Tetarwal, J. P.
The experiment was conducted to evaluate the efficacy of post emergence applications of imazethapyr on weed control and soybean yield. The field was infested with grassy weeds (51.6%), broad leaf weeds (34.1%) and sedges (13.2%). Application of imazethapyr XL 10% SL at 150 g/ha as post emergence significantly reduced the density of all grassy, broad leaf weeds sedges and their dry weight, and provided maximum number of branches/plant, pods/plant, seeds/pod and seed yield as compared to weedy check and imazethapyr 10% at 50 g/ha. Infestation of weeds throughout the growth period caused 57.2% reduction in seed yield of soybean. Maximum seed yield (1075 kg/ha) and weed control efficiency of grasses (86.9%), broad leaf (88.4%) and sedges (73.0%) was obtained with 2 hand weeding at 20 and 40 days after sowing closely followed by imazethapyr XL 10% at 150 g/ha (957 kg/ha). Application of imazethapyr XL 10% SL at 100 g/ha recorded significantly higher net return (Rs 14,237/ha) and B: C ratio (1.68) followed by imazethapyr XL 10% at 150 g/ha over weedy check and imazethapyr XL 10% at 50 g/ha.
Mostrar más [+] Menos [-]Efficacy of imazethapyr on weed management in soybean
2011
Meena, D.S. | Ram, Baldev | Jadon, Chaman | Tetarwal, J. P.
The experiment was conducted to evaluate the efficacy of post emergence applications of imazethapyr on weed control and soybean yield. The field was infested with grassy weeds (51.6%), broad leaf weeds (34.1%) and sedges (13.2%). Application of imazethapyr XL 10% SL at 150 g/ha as post emergence significantly reduced the density of all grassy, broad leaf weeds sedges and their dry weight, and provided maximum number of branches/plant, pods/plant, seeds/pod and seed yield as compared to weedy check and imazethapyr 10% at 50 g/ha. Infestation of weeds throughout the growth period caused 57.2% reduction in seed yield of soybean. Maximum seed yield (1075 kg/ha) and weed control efficiency of grasses (86.9%), broad leaf (88.4%) and sedges (73.0%) was obtained with 2 hand weeding at 20 and 40 days after sowing closely followed by imazethapyr XL 10% at 150 g/ha (957 kg/ha). Application of imazethapyr XL10% SLat 100 g/ha recorded significantly higher net return (Rs 14,237/ha) and B: C ratio (1.68) followed by imazethapyr XL 10% at 150 g/ha over weedy check and imazethapyr XL 10% at 50 g/ha.
Mostrar más [+] Menos [-]Effects of flavone 6-substitutions on GABAA receptors efficacy Texto completo
2011
Ren, Lihuan | Chan, Wing Man | Wang, Feng | Xu, Zhiwen | Zhao, Cunyou | Mat, Wai Kin | Chai, Yanwen | Wong, J Tze-Fei | Tsang, Shui Ying | Xue, Hong
Flavones have been studied for their activities via benzodiazepine site on the type-A γ-aminobutyric acid (GABAA) receptors, for which knowledge on structure–efficacy relationships has been rather limited in comparison to that on structure–affinity relationships. The present study focused on flavone 6-substitution, implied in previous studies being relevant to efficacy. Structure analogs, each varying only at position 6, were compared, including 6-fluoroflavone, 6-chloroflavone, 6-bromoflavone, and 2′-hydroxyflavone analyzed in the present study, as well as 6,2′-dihydroxyflavone reported earlier. Radio-ligand binding assays, whole-cell patch-clamp, and mouse behavioral experiments were performed. In consistent with a previous report, the present whole-cell patch-clamp and animal behavior experiments demonstrated 6-bromoflavone to be a positive modulator at GABAA receptors acting through flumazenil-sensitive high-affinity benzodiazepine site. In contrast, the other two 6-haloflavones were both neutralizing modulators. In vitro electrophysiological and in vivo animal experiments showed that 2′-hydroxyflavone was a neutralizing modulator, different in efficacy from its structural analog, 6,2′-dihydroxyflavone, a negative modulator of GABAA receptors. The fact that flavone analogs differing only at position 6 showed drastically different pharmacological properties clearly points to 6-substitution being an important determinant of efficacy. The results suggest that a large width of the first atom on the 6-substituent favors a high binding affinity of the 6-substituted flavone, whereas a large overall volume of the 6-substituent favors positive modulator activity, which could be modified by, e.g., 2′-hydroxyl substitution. These findings have contributed to the understanding of quantitative structure–efficacy relationships for flavones acting at GABAA receptors, and hence facilitation of flavone-based drug development.
Mostrar más [+] Menos [-]Field Efficacy of Imidacloprid on Okra Sucking Pest Complex
2011
Raghuraman, M. | Birah, Ajanta
Field trials were undertaken during late kharif of 2004 and 2005 with okra (Abelmoschus esculentus-var. Pusa Sawani) to evaluate the efficacy of imidacloprid 17.8% SL against sucking pest complex. Imidacloprid @ 80 g ai/ha significantly suppressed whitefly and leafhopper populations, and consequently increased the yield. The maximum yield (508.8 kg/ha, 1188.8 kg/ha) was recorded in imidacloprid (80g ai/ha) followed by its lower dose 40g ai/ha (455.5 kg/ha, 1055.5 kg/ha) during 2004 and 2005, respectively. The results suggest that neonicotinoids are potential alternatives to conventional insecticides and could be used in formulating a successful management strategy for sucking pests in okra.
Mostrar más [+] Menos [-]Efficacy of Foliar Fungicides in Controlling Fire on Daffodils Texto completo
2011
Chastagner, G. | DeBauw, A.
Fire, caused by the fungus Botryotinia polyblastis (Botrytis polyblastis), can completely kill the foliage in a field of daffodils (Narcissus pseudonarcissus) within a few weeks under warm, moist conditions in the spring. The premature death of foliage reduces bulb yields and subsequent flower production. In the Pacific Northwest, research has shown that one or two applications of a dicarboximide fungicide when the disease first appears can provide very effective control of this disease. Because a number of newer Botrytis fungicides are now on the market, a trial was established to determine their effectiveness in controlling the development of fire on ‘Gigantic Star’ daffodils in a commercial field with a history of problems with this disease. Two plots were established. Each was a randomized complete block design with five blocks containing 1.2 m of row per treatment. Treatments were applied on 20 April and 3 May, 2006. All treatments were applied in the equivalent of 935.3 L of water per ha. Disease was rated on a scale of 0 to 10, where 0 = none, 1 = 1-10%, 2 = 11-20%, … and 10 = 91-100% of foliage still green. By late May, virtually all of the foliage had been killed in the checks. The most effective treatments in both plots were applications of 26 GT (iprodione). Applications of Switch (cyprodinil plus fludioxonil), Daconil Ultrex (chlorothalonil), Daconil Weather Stik (chlorothalonil), Medallion (fludioxonil), Vangard (cyprodinil), Insignia (pyraclostrobin), and Dithane Rainshield (mancozeb) reduced disease development, but were not as effective as 26 GT. By early June, the plants treated with the high rate of 26 GT were the only plants that retained a significant amount of green foliage. Of the 10 fungicides included in these trials, the dicarboximide fungicide (26 GT) was the most effective material in controlling fire on daffodils.
Mostrar más [+] Menos [-]Quality, safety and efficacy of follow-on biologics in Japan Texto completo
2011
Yamaguchi, Teruhide | Arato, Teruyo
Recently, WHO, EU, Japan and Canada have published guidelines on biosimilar/follow-on biologics. While there seems to be no significant difference in the general concept in these guidelines, the data to be submitted for product approval are partially different. Differences have been noted in the requirements for comparability studies on stability, prerequisites for reference product, or for the need of comparability exercise for determination of process-related impurities. In Japan, there have been many discussions about the amount and extent of data for approval of follow-on biologics. We try to clarify the scientific background and rational for regulatory pathway of biosimilar/follow-on biologics in Japan in comparison with the guidelines available from WHO, EU and Canada. In this article, we address and discuss the scientific background underlying these differences to facilitate the harmonization of follow-on biologic principles in the guidelines in future.
Mostrar más [+] Menos [-]Mycorrhizal efficacy of trifoliate orange seedlings on alleviating temperature stress Texto completo
2011
Wu, Q.S.,Yangtze Univ., Jingzhou (China). Coll. of Horticulture and Gardening
The present experiment was conducted to evaluate the effects of Glomus mosseae on growth, root morphology, superoxide dismutase (SOD) and catalase (CAT) activities, and soluble protein content of trifoliate orange (Poncirus trifoliata) seedlings at low (15 deg C), optimum (25 deg C) and high (35 deg C) temperatures. Sixty-eight days after temperature stresses, mycorrhizal colonization and number of both entry points and vesicles were significantly inhibited by low or high temperature. Mycorrhizal seedlings recorded significantly higher growth characteristics than non-mycorrhizal seedlings at both optimum and high temperatures, but the beneficial effects were almost lost at low temperature. Generally, mycorrhizal seedlings presented notably higher root traits (projected area, surface area, number of forks and volume) than non-mycorrhizal seedlings regardless of temperature levels. Mycorrhizal colonization significantly increased SOD and CAT activities and soluble protein content at high temperature, increased only SOD activity at optimum temperature, and decreased only soluble protein content at low temperature. It suggests that mycorrhizal alleviation of temperature stress in trifoliate orange seedlings was at high temperature, but the alleviation was obviously weakened at low temperature.
Mostrar más [+] Menos [-]Efficacy of herbicides on Weeds grown in Triticale (Triticale hexaploide)
2011
parviz Sharifi Ziveh, Ardebil Agricultural and Natural Resources Research Center
To evaluate the Efficacy of herbicides on Weeds grown in Triticale(Triticale hexaploide) a field experiment was conducted in a randomized complete block design with four replications in Moghan in 2011. Treatments were included dual herbicide sulfosulfuron (Apiros®) (26.6 g/ha), mesosulfuron+Eudosulfuron (Atlantis®) (1.5 L/ha) metsulfuron-methyl+sulfosulfuron (Total®) (40 g/ha) plus surfactantyl (1250 mL/ha), isoproton+diflofenikan (Panther®) (2L/ha) and clodinaphop proparghyl (Topic®)(0.8L/ha) pinoksaden (Axial®)(1.5 l/ha) diclofop metyl (Iloxan®) (2.5 L/ha), pinocsaden+clodinafop propargil (Traxus®) (1.5L/ha), phenoxaprop -ethyl +mphen paper d-ethyl (Pumasuper®) (0.8L/ha) Tralkoxydim (Grasp) (1.2 L/ha) plus liter of oil, flem-prep-M isopropyl (Suffix B W ®) (4L/ha) against Triticale weeds beside a control. The results showed that narrow-leaf weeds wild oat and pegweed were dominant. All herbicides except Grasp had desirable effects on narrow-leaf weeds withoue any effect on yield loss.Also, in some cases of herbicide effects are observed an ignorable paleness in Triticale but this effect did not cause yield loss. Key
Mostrar más [+] Menos [-]Mycorrhizal efficacy of trifoliate orange seedlings on alleviating temperature stress Texto completo
2011
Wu, Q.S.
Citrus plants often suffer from temperature stress, which seriously inhibits tree growth and even results in tree death. The present experiment was conducted to evaluate the effects of Glomus mosseae on growth, root morphology, superoxide dismutase (SOD) and catalase (CAT) activities, and soluble protein content of trifoliate orange (Poncirus trifoliata) seedlings at low (15°C), optimum (25°C) and high (35°C) temperatures. Sixty-eight days after temperature stresses, mycorrhizal colonization and number of both entry points and vesicles were significantly inhibited by low or high temperature. Mycorrhizal seedlings recorded significantly higher growth characteristics than non-mycorrhizal seedlings at both optimum and high temperatures, but the beneficial effects were almost lost at low temperature. Generally, mycorrhizal seedlings presented notably higher root traits (projected area, surface area, number of forks and volume) than non-mycorrhizal seedlings regardless of temperature levels. Mycorrhizal colonization significantly increased SOD and CAT activities and soluble protein content at high temperature, increased only SOD activity at optimum temperature, and decreased only soluble protein content at low temperature. It suggests that mycorrhizal alleviation of temperature stress in trifoliate orange seedlings was at high temperature, but the alleviation was obviously weakened at low temperature.
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