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991.
用沙棘种子油对狗(12只,性别随机)的急性消炎能力进行了研究。急性炎症试验部位都选择在狗的背部。使用游标卡尺连续7d测量皮肤上发炎部位的情况来检测沙棘种子油的消炎能力。结果说明沙棘种子油有抗炎的能力。同时使用棉球肉芽肿瘤测定法测定了沙棘种子油对狗(12只)皮肤的慢急性炎症的消炎能力。沙棘油对狗皮肤慢性炎症的抗感染能力太弱以致于无法检测到。  相似文献   
992.
The present study reports the results of a field-basedexperiment conducted to assess the effect of simulated acid rain(SAR) of different pH i.e. 5.6 (control), 5.0, 4.5, 4.0 and 3.0on two cultivars of wheat (Triticum aestivum, Malviya 213(M213) and Sonalika). Shoot and root lengths significantlydeclined at pH 3.0 in both varieties. Leaf area declined at pH4.0 and 3.0 in M213 at both ages and at 75 days in Sonalika.Total biomass of 75 days plants declined significantly at pH range4.5–3.0 in M213 and at pH 4.0 and 3.0 in Sonalika. Netassimilation rate (NAR) declined significantly at pH 3.0 inboth varieties. Compared to control, yield of M213 showedsignificant reductions at pH 4.0 and 3.0, whereas Sonalikaresponded negatively at pH 3.0. The study showed that acid rainhas a significant negative effect on wheat plant performance.  相似文献   
993.
Afforestation and reforestation of pastures are key land-use changes in New Zealand that help sequester carbon (C) to offset its carbon dioxide (CO2) emissions under the Kyoto Protocol. However, relatively little attention has been given so far to associated changes in trace gas fluxes. Here, we measure methane (CH4) fluxes and CO2 production, as well as microbial C, nitrogen (N) and mineral-N, in intact, gradually dried (ca. 2 months at 20 °C) cores of a volcanic soil and a heavier textured, non-volcanic soil collected within plantations of Pinus radiata D. Don (pine) and adjacent permanent pastures. CH4 fluxes and CO2 production were also measured in cores of another volcanic soil under reverting shrubland (mainly Kunzea var. ericoides (A. Rich) J. Thompson) and an adjacent pasture. CH4 uptake in the pine and shrubland cores of the volcanic soils at field capacity averaged about 35 and 14 μg CH4-C m−2 h−1, respectively, and was significantly higher than in the pasture cores (about 21 and 6 μg CH4-C m−2 h−1, respectively). In the non-volcanic soil, however, CH4-C uptake was similar in most cores of the pine and pasture soils, averaging about 7-9 μg m−2 h−1, except in very wet samples. In contrast, rates of CO2 production and microbial C and N concentrations were significantly lower under pine than under pasture. In the air-dry cores, microbial C and N had declined in the volcanic soil, but not in the non-volcanic soil; ammonium-N, and especially nitrate-N, had increased significantly in all samples. CH4 uptake was, with few exceptions, not significantly influenced by initial concentrations of ammonium-N or nitrate-N, nor by their changes on air-drying. A combination of phospholipid fatty acid (PLFA) and stable isotope probing (SIP) analyses of only the pine and pasture soils showed that different methanotrophic communities were probably active in soils under the different vegetations. The C18 PLFAs (type II methanotrophs) predominated under pine and C16 PLFAs (type I methanotrophs) predominated under pasture. Overall, vegetation, soil texture, and water-filled pore space influenced CH4-C uptake more than did soil mineral-N concentrations.  相似文献   
994.
The opium latex of 1470 individual plant samples of 98 germplasm lines were screened for five major economic alkaloids. The alkaloids profile showed that morphine content ranged from 9.20–20.86% with an average of 15.00 ± 0.267. Codeine ranged from 1.69–6.48% with arithmetic mean of 3.35 ± 0.091, thebaine from 0.52–7.95% with an average of 2.27 ± 0.116. Narcotine ranged from 8.79–17.97% with an average 8.79 ± 0.266 and papaverine content ranged from 0.00–6.07% with an average 1.18 ± 0.167 in over all the germplasm lines. The content of different alkaloids categorized into class interval which exhibited that maximum number of plants and accessions for morphine content fall in group of 10–15% followed by 15–20%, for codeine content in group of 2–4% followed by 4–6%, for thebaine content in 1–2% followed by 2–4%, for narcotine in 5–10% followed by 10–15% and for papaverine content 0–2%. 24 germplasm lines had morphine content above 16.0%. Similarly, 37 germplasm lines for codeine and 13 for thebaine showed consistently high content, i.e., above 3%. 33 germplasm lines had narcotine content above 9% and 20 lines exhibited papaverine content above 2%. Line BR 316 was found unique having thebaine content 6.27–9.33%. The probable reasons of increase or decrease of different alkaloids based on their biosynthetic pathway has been discussed in detail.  相似文献   
995.
Summary Among the nematodes infesting chickpea (Cicer arietinum L.) plants in Syria, cyst nematode (Heterodera ciceri Vovlas, Greco et Di Vito) is the most important. It is uneconomical to grow chickpea in fields infested with cyst nematode and to control this nematode with nematicide. Therefore, investigations were conducted at ICARDA, Syria from 1987 to 1991 to identify sources of resistance to cyst nematode in 7258 lines of C. arietinum and 102 lines of eight annual Cicer species including C. bijugum K.R. Rech. (13 lines), C. chorassanicum (Bge) M. Pop. (3 lines), C. cuneatum Hochst. ex Rich. (3 lines), C. echinospermum P.H. Davis (8 lines), C. judaicum Boiss. (18 lines), C. pinnatifidum Jaub. & Sp. (18 lines), C. reticulatum Ladiz. (36 lines), and C. yamashitae Kitamura (3 lines). All lines were grown in a greenhouse at 15–25°C in pots containing soil infested with 20 eggs of the nematode g-1 soil. Nematode infestation was evaluated on a 0 to 5 scale based on number of females and cysts on roots. Resistance was found in one line of C. bijugum, six lines of C. pinnatifidum, and one line of C. reticulatum. No lines of C. arietinum, C. chorassanicum, C. cuneatum, C. echinospermum, C. judaicum, or C. yamashitae was resistant to cyst nematode. Plants with resistance have been recovered in the F3 generation from crosses between the cultigen and C. reticulatum, indicating the possibility of transfer of gene(s) for resistance to cyst nematode from wild to cultivated Cicer species.Joint contribution from Istituto di Nematologia Agraria, ICARDA and ICRISAT (International Crops Research Institute for the Semi-Arid Tropics), Patancheru P.O., A.P. 502 324, India.  相似文献   
996.

The ability of fly ash to remove fluoride from water and wastewaters has been studied at different concentrations, times, temperatures and pH of the solution. The rate constants of adsorption, intraparticle transport, mass transfer coefficients and thermodynamic parameters have been calculated at 30, 40, and 50 °C. The empirical model has been tested at various concentration for the present system. The removal of fluoride is favorable at low concentration, high temperature and acidic pH.

  相似文献   
997.
998.
Summary There was no correlation between the quantity of exopolysaccharide produced and acetylene reduction activity by Rhizobium spp. or by Bradyrhizobium spp. (Cajanus). The exopolysaccharide-defective mutants of Rhizobium sp. strain P 116 either failed to nodulate or showed a decrease in effectiveness. The deficiency in exopolysaccharide production was corrected by the addition of purified exopolysaccharide from the parent strain, or from Bradyrhizobium sp. strain P 149 or S24 isolated from pigeonpea (Cajanus cajan) and mungbean (Vigna radiata), respectively. However, the nodules so formed were not fully effective compared to those formed by the parent strain.  相似文献   
999.
Three hundred and forty five accessions of pea of diverse origin, height, leaf types and disease reaction were screened for rust disease severity and area under disease progress curve (AUDPC). The frequency of slow rusting types in the tall, dwarf, early and late groups appeared comparable. Of the 345 accessions, forty-four genotypes were evaluated for disease intensity, which was converted into AUDPC, number of pustules/leaf and pustule size. Wide range of variation was found for these traits. The slow rusting attribute of 16 genotypes was further confirmed by testing these under unprotected (inoculated) and protected (fungicidal spray) conditions for two successive years for disease intensity by assessing the AUDPC, seed yield/plot, and 100-seed weight. The fast rusting genotypes exhibited lower AUDPC, accompanied with increased seed yield and seed weight when grown under the protected condition, as compared to those raised under the unprotected condition. The genotypes Pant P 11, FC 1, HUDP 16, JPBB 3 and HUP 14 appeared as slow rusting genotypes.  相似文献   
1000.
Abstract. The effects of rice-straw management (incorporation, burning or removal) on soil organic carbon content and physical and hydraulic properties were determined after five years of rice–wheat cropping in a sandy loam soil in northwest India. Soil organic carbon content was greater with straw incorporation and straw burning than with straw removal, and aggregation status, total porosity, pore-size distribution, bulk density, dispersion ratio and soil strength were correspondingly improved. The treatment effects were confined mainly to the 0–5 cm depth. Water retention was less with straw burning than straw removal, owing to increased water repellency of the soil surfaces. Cumulative infiltration and its rate after five hours were greater with straw incorporation than straw burning or removal. Air entry values were unaffected by straw management; however, the values were greater after rice harvest than after wheat harvest.  相似文献   
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