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31.
Salah MA Bedir E Toyang NJ Khan IA Harries MD Wedge DE 《Journal of agricultural and food chemistry》2003,51(26):7607-7610
Hexane and ethyl acetate phases of the methanol extract of Macaranga monandra showed fungal growth inhibition of Colletotrichum acutatum, C. fragariae and C. gloeosporioides, Fusarium oxysporum, Botrytis cinerea, Phomopsis obscurans, and P. viticola. Bioassay-guided fractionation led to the isolation of two active clerodane-type diterpenes that were elucidated by spectroscopic methods (1D-, 2D-NMR, and MS) as kolavenic acid and 2-oxo-kolavenic acid. A 96-well microbioassay revealed that kolavenic acid and 2-oxo-kolavenic acid produced moderate growth inhibition in Phomopsis viticola and Botrytis cinerea. 相似文献
32.
The objective of this study was to investigate the effects of five isonitrogenous (35% crude protein) diets having different
energy contents; 10.85, 11.82, 12.73, 13.69, and 15.06 MJ DE/kg, respectively, on the gonad development and weight gain of
Sharptooth catfish fingerlings. Energy contents of the experimental diets were increased with the increasing amount of soy-acid
oil (0, 4, 8.5, 13, 18%) and each group of fish was fed on their respective diets (group I was fed diet I) during 180 days.
The gonad maturation was significantly affected by dietary energy. In both sexes, the histological inspections of the gonads
did reveal differences among the fish fed different energetic diets. Fish fed diets I, II, and III had significantly heavier
and more developed gonads compared to those on diets IV and V. Fish fed the higher energetic diets (IV and V) had partially
low numbers of yolky oocytes compared to other groups. The mean GSI values of female and male fish fed with diet III was significantly
greater than those fed diets with higher dietary energy; however, higher HSI values were recorded for fish fed with the higher
energetic diets (IV and V). Also, the best weight gain for both males and females were recorded from the fish fed diet III
(12.73 MJ DE/kg). Therefore, on the basis of the present results, among energy levels tested, 12.73 MJ DE/kg was found to
be optimal for healthy gonad development and weight gain. 相似文献
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34.
BACKGROUND: Adjuvants can improve pesticide application efficiency and effectiveness. However, quantifications of the adjuvant‐amended pesticide droplet actions on foliage, which could affect application efficiencies, are largely unknown. RESULTS: Droplet evaporation rates and spread on waxy or hairy leaves varied greatly with the adjuvant types tested. On waxy leaves, the wetted areas of droplets containing crop oil concentrate (COC) were significantly smaller than those containing modified seed oil (MSO), non‐ionic surfactant (NIS) or oil surfactant blend (OSB), whereas the evaporation rates of COC‐amended droplets were significantly higher. On hairy leaves, COC‐amended droplets remained on top of the hairs without wetting the epidermis. When the relative concentration was 1.50, the wetted area of droplets with NIS was 9.2 times lower than that with MSO and 6.1 times lower than that with OSB. The wetted area increased as the adjuvant concentration increased. MSO‐ or OSB‐amended droplets spread extensively on the hairy leaf surface until they were completely dried. CONCLUSION: These results demonstrated that the proper concentration of MSO, NIS or OSB in spray mixtures improved the homogeneity of spray coverage on both waxy and hairy leaf surfaces and could reduce pesticide use. Published 2011 by John Wiley & Sons, Ltd. 相似文献
35.
Scott HM Fosgate GT Libal MC Sneed LW Erol E Angulo AB Jordan ER 《American journal of veterinary research》2007,68(3):236-245
36.
AbstractThis study aimed to assess the efficiencies of composts and vermicomposts obtained from two different composting methods on the growth, mineral nutrition and nutrient uptake of wheat. Composts and vermicomposts were applied to plastic pots under greenhouse condition with the application doses of 0, 5, 10, 20, and 40 t ha?1. The pot-experiment lasted three months. The results showed that plant dry weight increased with the increase in doses when compared to the control groups where no composts and vermicomposts were applied. However, no differences were found among the doses from 5 to 40 t ha?1 of composts and vermicomposts. Although application doses did not affect significantly on the most of the plant nutrient concentrations, Fe concentration in plant decreased with the increase in application doses. Additionally, no significant differences among the composts and vermicomposts on plant nutrient concentrations except for Mg were detected. Comparing to the control dose (0 t ha?1), nutrient uptakes by plant from the soil significantly increased with the increase of application doses, but no significant differences were determined amongst the doses of 5 and 40 t ha?1, generally. The effect of production methods on the most of investigated parameters including plant dry weight was similar. 相似文献
37.
Melatonin alleviates cold‐induced oxidative damage in maize seedlings by up‐regulating mineral elements and enhancing antioxidant activity 
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下载免费PDF全文 Melatonin, known as an animal hormone and an antioxidant with a low molecular weight, is one of the most commonly used substances to improve plant resistance against various environmental stresses. However, there are no studies explaining the effects of melatonin on the relationship between defense system and mineral composition of plants under stressed and unstressed‐conditions. The present study was conducted to investigate whether the mitigating effect of melatonin is associated with its modulating influence on the mineral elements of cold‐stressed maize seedlings. The seedlings were treated with melatonin (1 mM) and cold stress (10/7°C) for 3 d separately and in combination. After 3 d, the seedlings were harvested to determine several physiological, biochemical, and molecular parameters. Melatonin application effectively mitigated the damages from cold stress, as demonstrated by higher relative water concentration, chlorophyll concentration and antioxidant enzyme activities (superoxide dismutase, guaiacol peroxidase, catalase, ascorbate peroxidase, and glutathione reductase), as well as lower superoxide, hydrogen peroxide, and malondialdehyde concentrations. Similarly, melatonin significantly ameliorated cold‐induced reductions in the concentrations of potassium, phosphorus, sulfur, magnesium, iron, copper, manganese, and zinc. Besides, it further increased calcium and boron concentrations compared to cold stress alone. Our results reveal that melatonin has an important modulating influence on the mineral element composition of plants and mitigates cold stress through up‐regulation of these elements and simultaneously enhanced antioxidant activity. 相似文献
38.
Effects of organic and synthetic fertilizer sources on pest and predatory insects associated with tomatoes 总被引：1，自引：0，他引：1
The effects of organic (composted cow manure) and synthetic (NPK) fertilizers on pests (aphids and flea beetles) and predatory
arthropods (anthocorids, coccinellids and chrysopids) associated with tomatoes were evaluated in a 2-year randomized complete
block field experiment. Our data suggested that the application of either organic or synthetic fertilizers could increase
pest populations on tomatoes. However, there were lower populations of aphids on tomatoes grown with the organic fertilizer
than on those grown with the synthetic fertilizers in the second year of the experiment, indicating that organic fertilizers
may have the potential to reduce pest attacks in the long term. Anthocorid populations were larger on tomato plants with high
aphid populations in the synthetic than in the organic fertilizers-treated plots.
http://www.phytoparasitica.org posting July 6, 2003. 相似文献
39.
Xingyuan?Men Feng?GeEmail author Clive?A.?Edwards Erdal?N.?Yardim 《Phytoparasitica》2004,32(3):246-254
The effects of pesticide applications on pests (aphids and acarid mites) and predators (ladybeetles and spiders) were investigated
in transgenicBt cotton and nontransgenic cotton agroecosystems in 1999, 2000 and 2001. Transgenic cotton did not cause changes in populations
of acarids and did not reduce numbers of predators considerably; its effects on aphids were inconsistent. Although insecticides
were not applied against the main pest — cotton bollworm — on transgenic cotton, the total number of insecticide applications
in 3 years was no less than the total applied on nontransgenic cotton, because additional applications were required against
sucking pests on transgenicBt cotton. Pesticide applications decreased numbers of aphids, acarids and predatory spiders significantly on both transgenic
and nontransgenic cottons. The results suggest that the use ofBt cotton should be evaluated carefully in China.
http://www.phytoparasitica.org posting April 30, 2004. 相似文献
40.
An experiment was conducted under greenhouse conditions to test the symbiotic performance and plant nutrient uptake of the twelve nationally registered chickpea cultivars (‘Çak?r’, ‘I??k-05’, ‘Can?tez-87’, ‘Hisar’, ‘Ya?a-05’, ‘Azkan’, ‘Küsmen-99’, ‘Gökçe’, ‘Damla-89’, ‘Diyar-95’, ‘Aziziye-94’, and ‘?zmir-92’) in Turkey. Inoculation with Mesorhizobium ciceri increased the average nodule number by 687%, nodule weight by 257%, plant height by 6%, shoot dry weight by 12%, root dry weight by 21%, chlorophyll content by 4.2%, nitogen (N)% by 7.9%, and total N by 22.7%. Averaged across chickpea cultivars, inoculation also significantly increased sulfur (S) by 14.4%, phosphorus (P) by 1.9%, magnesium (Mg) by 13.8%, potassium (K) by 6.2%, calcium (Ca) by 17.4%, copper (Cu) by 4.5%, iron (Fe) by 16.5%, manganese (Mn) by 10.9% and zinc (Zn) uptake by 9.4%. The macro- and micronutrient uptake of cultivars significantly correlated with their nitrogen content and the magnitude of response to inoculation in relation to nodulation, plant growth, nitrogen fixation, and nutrient uptake significantly varied among cultivars. Based on the amount of fixed N and plant nutrient uptake, ‘Azkan’, ‘Aziziye-94’, ‘Küsmen-99’, ‘Diyar-95’, and ‘Hisar’ were the genotypes with the most positive response to inoculation. Our data showed that nodulation, nitrogen fixation, plant dry matter production, and macro- and micronutrient uptake of the inoculated chickpea can be improved by selecting the best compatible cultivar. 相似文献