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From the year 2000 on, different steps have been taken to study the real extent of pesticide use in Germany. For this paper, the data of farms in North East Germany were examined for the chemical plant protection measures carried out between 2000 and 2004. Results are presented for 97 winter wheat fields and 68 fields of oil seed rape. Pesticide use intensity is described as frequency of use, number of pesticides used, and treatment frequency index. Number and composition of tank mixtures are given in detail. More over it can be shown that the use of reduced dosages contributes to smaller overall pesticide use intensity. 相似文献
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G. V. Subbarao C. Johansen J. V. D. K. Kumar Rao M. K. Jana 《Biology and Fertility of Soils》1990,9(1):49-53
Summary There were significant differences among pigeonpea [Cajanus cajan (L.) Millsp] Rhizobium sp. strains (IC 3506, IC 3484, IC 3195, and IC 3087) in their ability to nodulate and fix N2 under saline conditions. Pigeonpea plants inoculated with IC 3087 and IC 3506 were less affected in growth by salinity levels of 6 and 8 dS m-1 than plants inoculated with the other strains. For IC 3506, IC 3484, and IC 3195, there was a decrease in the number of nodules with increasing salinity, while the average nodule dry weight and the specific nitrogenase activity remained unaffected. However, in IC 3087, the number of nodules increased slightly with increasing salinity. Leaf-P concentrations increased with salinity in the inoculated plants irrespective of the Rhizobium sp. strain, and leaf-N concentrations decreased with increasing salinity in IC 3484 and IC 3195 only. Shoot-Na and-Cl levels were further increased in these salt-sensitive strains only at 8 dS m-1. Therefore there may be scope for selecting pigeonpea Rhizobium sp. symbioses better adapted to saline conditions. The Rhizobium sp. strains best able to form effective symbioses at high salinity levels are not necessarily derived from saline soils.Submitted as JA No. 919 by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) 相似文献
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The effects of Hg, As, Pb, Cu, Cd, and Cr (1, 2, and 5 mg L?1 each) on Azolla pinnata R. Br. were analyzed. The treatments (2 and 5 mg L?1) of the heavy metal pollutants decreased Hill activity, chlorophyll, protein and dry wt, and increased tissue permeability over control values. The effects were most pronounced with the treatment of 5 mg L?1. The harmful effects of the metals were, in general, found by the treatments in the order: Cd 〉 Hg 〉 Cu 〉 As 〉 Pb 〉 Cr. There was no significant change in these parameters at 1 mg L?1 of the metals over control. Thus Azolla pinnata shows tolerance to the heavy metals tested up to 1 mg L?1 each. 相似文献
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Effect of Thermal Energy Intensity on Time and Rate of Nitrogen Accumulation by Maize (Zea mays L.)1
A. Olness G. R. Benoit K. van Sickle Jana Rinke 《Journal of Agronomy and Crop Science》1990,164(5):312-320
The effect of thermal energy intensity (TEI) on the rate of nitrogen (N) accumulation by maize from a Hamerly clay loam soil (Aerie Calciaquoll) was examined with and without supplemental irrigation. Soil- and air-TEI expressed as cumulative growing degree days (GDD) was determined from hourly temperature measurements taken within each plot at soil depths of 0.05-, 0.15-, and 0.3-m and at a height of 1.2-m above ground surface. A daily mean TEI (GDD per day) was calculated for each growth period. Estimates of time coefficient(s), k, in uni- and diphasic tanh[k(time)] functions, plotted against mean TEI for the periods; 1) planting to emergence, 2) emergence to eighth leaf, 3) eighth leaf to time(s) of maximum N accumulation rate, (t0), 4) planting to t0, 5) emergence to t0, 6) first diphasic maximum accumulation rate (t01) to 50 % silking, and 7) silking to second diphasic maximum accumulation rate t02 showed several linear relationships. Uniphasic time coefficients were modelled as functions of air-TEI. The first diphasic time coefficient, k1 was modelled as a function of pre- and post-emergent soil-TEI. Attempts to model k2, the second time coefficient of the diphasic model were unsuccessful; however, this time coefficient was linearly related to TEI for the growth period ‘t01, to 50 % silking’ and curvilinearly related to k1. 相似文献
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Ilva Nakurte Kristaps Klavins Inga Kirhnere Jana Namniece Liene Adlere Jaroslavs Matvejevs Arta Kronberga Aina Kokare Vija Strazdina Linda Legzdina Ruta Muceniece 《Journal of Cereal Science》2012
Lunasin is a novel, cancer-preventive, anti-inflammatory and cholesterol-reducing peptide that was originally isolated from soy and later from barley, wheat and rye. We report the first discovery of lunasin in triticale (X Triticosecale Wittmack). Moreover, we report first data of lunasin content in winter rye and wheat genotypes grown in Northern Europe. These data are novel as previously published data on finding of lunasin in cereals were obtained in genotypes grown in Korea. Lunasin content was uncovered using a previously published procedure for isolation from cereals and identified by LC-MS/MS assay. We found that triticale was the most lunasin-rich cereal, with the tested genotypes displaying the following trend in lunasin content: genotype 0002-26 > Dinaro > DSGU 10/94 > 0213-22 > 0317-14 > 0006-31. The greatest lunasin content was 6.46 mg/g in the grain of triticale genotype 0002-26. In comparison, the highest lunasin content in rye variety Dankovske Diament was 1.5 mg/g, and the highest lunasin content in the winter wheat variety Fredis was 0.23 mg/g. We conclude that triticale can play a significant role as functional food, with great potential for the use of triticale products in human and animal diets. 相似文献
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Janaína?Camacho?da?Silva Antonio?Sergio?Varela Junior J?sie?Shwartz?Caldas Clarissa?da?Silva Freitas Joziel?Gon?alves?Botelho Elton?Pinto?Colares Carine?Dahl?CorciniEmail authorView authors OrcID profile 《Fish physiology and biochemistry》2016,42(1):93-102
Sperm quality tests on fish are classically used for evaluating cryopreservation procedures, and they are also promising to assess aquatic toxicity and biomarkers of xenobiotic effects on reproduction. Osmotic shock from the storage medium is one of the main factors affecting sperm quality during evaluation. Thus, the objective of this study was to evaluate the effects of different osmolalities (240–460 mOsm/kg) for at least 4 days on the sperm quality parameters of the viviparous fish Jenynsia multidentata. The level of significance was (P < 0.05). The plasma osmolality of J. multidentata is 326 ± 3.9 mOsm/kg. The motility of fresh semen was higher in osmolalities of 280 and 300 mOsm/kg but did not differ between osmolalities from 240 to 320 mOsm/kg. Above 380 mOsm/kg, the motility observed was 0 %. Over the time period studied motility increased with increasing osmolality, and the most constant and long-lasting rates were between 300 and 320 mOsm/kg. On the 4th day of evaluation, higher membrane integrity rates were observed between 280 and 360 mOsm/kg, higher mitochondrial membrane potential was observed between 300 and 460 mOsm/kg, and higher DNA integrity rates were observed between 260 and 380 mOsm/kg. Moreover, osmolalities ≥460 and ≤240 resulted in the lowest motility and DNA integrity levels. Over 4 days, the plasma membrane integrity was significantly lower at ≤260 and ≥400 mOsm/kg, and the mitochondrial membrane potential was significantly lower only in osmolalities ≤240 mOsm/kg. Therefore, we conclude that for sperm quality preservation in J. multidentata, an osmolality of 300–320 mOsm/kg of the most suitable diluent is necessary. Furthermore, we conclude that the storage of sperm in a hyposmotic (<260 mOsm/kg) or hyperosmotic (>400 mOsm/kg) solution affects not only motility but also other sperm quality parameters. 相似文献
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