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1.
以亚麻籽油、大豆油、菜籽油与葵花籽油为原料,在不同温度条件下氧化并测定其不同时间的同步荧光光谱,分析同步荧光光谱及荧光物质变化情况。结果表明,4种植物油不同温度下的同步荧光光谱峰变化主要集中在300~415 nm内,且随着加热时间的延长存在波动现象;在50℃和150℃加热氧化条件下,300,330,375,415 nm这4个峰都存在明显的波动现象;二维相关分析表明,这4个峰的荧光强度变化速率不同,不同油变化差异较大;同种油在不同温度下,4个峰的波动情况、相互关系、变化速率均有明显差异。这些峰的变化与油脂氧化过程中荧光物质和油脂氧化程度的变化有关,可以利用同步荧光光谱的变化特性作为监控油脂氧化的依据。 相似文献
2.
M. Özgen 《Journal of Agronomy and Crop Science》1991,166(5):318-325
The purpose of this study was to compare responsiveness to environment as well as the stability of newly developed promising lines with traditional commercial cultivars. Subject research was conducted in Ankara between 1983-1989 on common and durum wheat cultivars and lines. Regression coefficient (b) was used as the criterion of genotypes' responsiveness to environment whereas deviation from regression (S2 d) and coefficient of determination (r2 ) were used as stability parameters. Each experiment year was regarded as an environment and yield average of each year was used as the environmental index.
In consequence of the research, it was determined that new varieties with high yield, adaptable to diverse environments could be developed by means of hybridizations between parents having different genetic characteristics which were provided from diverse ecological regions. 相似文献
In consequence of the research, it was determined that new varieties with high yield, adaptable to diverse environments could be developed by means of hybridizations between parents having different genetic characteristics which were provided from diverse ecological regions. 相似文献
3.
Root length of Holcus lanatus L. declined rapidly with increasing lead and zinc concentrations in nutrient solution. In all used Pb and Zn concentrations root growth of genotypes coming from a Pb-Zn mine area, was greater than that of the control, suggesting that these genotypes evolved tolerance to Pb and Zn.
Negative correlation was also observed between chlorophyll content and increased heavy metal concentrations. The greater chlorophyll content found in tolerant genotypes, in different Pb and Zn concentrations, in comparison with the control, could be served to distinguish tolerant and non-tolerant genotypes. 相似文献
Negative correlation was also observed between chlorophyll content and increased heavy metal concentrations. The greater chlorophyll content found in tolerant genotypes, in different Pb and Zn concentrations, in comparison with the control, could be served to distinguish tolerant and non-tolerant genotypes. 相似文献
4.
Two mungbean varieties, Guj-1 and PIMS-1 differing in their productivity potential, were examined to investigate their photosynthetic system at various stages of growth in relation to yield with two different dates of sowing. Vertical leaves were found to be beneficial. On the other hand, excessive leaf area during the later stages of growth may be detrimental to yield. Lower LAD at seedling stage and overall high NAR values may be reflected in higher grain yield. NAR declined as season progressed and this, in turn, may be related with increase in LAI. The grain yield was considerably more at the first date of sowing as compared to second date of sowing, the effect was being more pronounced in var. PIMS-1 . Various environmental factors recorded at two different dates of sowing and at various stages of growth indicated that these factors may have influenced the yield potential at two different dates of sowing. 相似文献
5.
Rapid Screening for Aluminum Tolerance in Cereals by Use of the Chlorophyll Fluorescence Test 总被引:1,自引:0,他引:1
The effects of aluminum on the photosynthetic apparatus were examined in cereals grown in nutrient solutions (pH 4.5) at two Al levels (0 and 148 μM). The chlorophyll fluorescence kinetics results confirmed that the soft wheat ‘BHG’ cultivar has the potential for growth on acid soils while triticale cultivars ‘Niovi’ and ‘Dada’ appeared to be relatively tolerant. The percentage decrease in Fv/Fm of the less tolerant cultivars after Al-treatment indicated a decrease in the efficiency of the primary photochemistry of PS II, while the decrease in the ratio FV/Fosuggested that exposure of the cultivars ‘Dio’ and ‘Appulo E’ to aluminum caused injury to the thylakoid structure. The percentage fluctuations of the ratio Fv/Fmwere shown to correlate very closely with the assessment of injury as evaluated by the relative top fresh weight. Measurements of chlorophyll fluorescence in vivo could be used to monitor injury caused by “Al-stress”, and thus they may serve as a rapid screening test for Al tolerance. 相似文献
6.
本文通过光合作用参数的测定,详细的研究了中系8541和8240两种不同产量水平的水稻品种的光合特性.论述了在含等量叶绿素的条件下,中系8541和中系8240之间在对光谱的吸收、叶片的光合作用量子转化效率,叶绿体的PSⅡ(光系统Ⅱ)潜在活性(Fv/F_0)和原初光能转化效率(Fv/Fm等的主要区别.实验结果说明,上述各光合作用参数中系8541都优于中系8240.不仅如此.在Mg~(2+)作用下,Fv/Fo和Fv/Fm比值的提高以及Mg~(2+)对两个光系统激发能分配的调节能力中系8541也强于中系8240. 相似文献
7.
在沙尘暴应急监测方法研究中,通过对总悬浮颗粒物采样仪器及各种采样参数的研究确定和降尘采样器的研制,制定出沙尘暴应急监测方法。 相似文献
8.
北疆棉花不同品种叶绿素荧光特性的研究 总被引:8,自引:3,他引:5
测定了北疆6个不同棉花品种田间叶片的净光合作用、荧光参数的变化。结果表明:晴天棉花叶片的光化学效率(Fv/Fm)随着光强上升而下降,到14∶00左右降到最低值,之后又随光强的减弱逐渐回升;非光化学猝灭系数(qN)则与此相反。棉叶在晴天易发生光抑制,可能会引发反应中心的降解等破坏反应。产量较高的新陆早8号和新陆早10号的Fv/Fm、光化学猝灭系数(qP)均高,且正午过后Fv/Fm恢复较快,不仅能较强地吸收光能,同时还具有较高的PSII的活性和光能转化效率,从而将所吸收的光能有效地转化为化学能,提高光合电子传递速度,形成更多的ATP和ENADPH,为光合碳同化提供充分的能量和还原能力。 相似文献
9.
《Livestock Production Science》2005,95(3):255-263
The aim of the experiment was to investigate the effects of cage floor and cage density on stress parameters of laying hens. A total of 162 brown laying hens (Hyline Brown), aged 34 weeks, were used in the experiment. Compact-type battery cages, with three floors, were used. Hens were allocated as one, three or five hens in each of 18 cages to obtain three different cage density groups of 1968, 656 and 393.8 cm2 floor area per hen, respectively. The same number of cages with different cage density were allocated to three different battery floors (first floor=top, second=middle, third=bottom) systematically. Values for body weight, mortality rate, egg weight, egg production, egg quality characteristics, egg yolk cholesterol content, the levels of blood plasma corticosterone, serum glucose, total cholesterol and triglycerides, the ratio of heterophils to lymphocytes (H-L ratio), antibody titers, claw length score, foot health score, plumage score and throat skin injuries were taken as indicators of stress. The values for egg weight (P<0.01) at the first floor were greater than the other floor levels. The group with five hens per cage had significantly lower mean estimates (P<0.01) than other groups with respects to body weight (P<0.001), egg production (P<0.001), egg weight (P<0.001) and plumage score (P<0.01), while significantly higher mean estimates for egg albumen index (P<0.01), Haugh unit (P<0.01), serum glucose (P<0.001), and H-L ratio (P<0.001). Serum cholesterol was higher in cages with one hen than that with five hens, whereas plasma corticosterone was lower. Antibody titers in cages with one hen was similar to that with three or five hens; however, those with three hens had higher titers than those with five hens. Values for egg breaking strength, yolk index, egg cholesterol content, and foot health score were not affected by cage density or floor. The results suggest that the allocation of three hens per cage had no measurable effect on health and welfare. 相似文献
10.
本研究选用40头胎次、产奶量、泌乳期相近的中国荷斯坦奶牛随机分成4组(n=10),试验组奶牛日粮中分别添加45、60和75mg/kg大豆黄酮,在试验前及试验开始后第10天、第20天和第30天颈静脉采血,测定4组奶牛血清钙、磷和葡萄糖水平。结果表明:与对照组相比较,试验1组中血清钙、磷和葡萄糖变化均不显著(P>0.05);试验2组仅血清钙在第30天时显著高于对照组(P<0.05);试验3组第10天和20天时血清钙水平显著高于对照组(P<0.05),第30天时血清钙水平极显著高于对照组(P<0.01),而血糖水平仅第30天显著高于对照组(P<0.05)。 相似文献