排序方式： 共有9条查询结果，搜索用时 546 毫秒
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2004年3~6月,选择胶州湾口近海作为研究海区,在栈桥、湛山湾和石老人3个站位每月取样两次,每次退潮后,在潮间带固定地点采集底质样品,分别测定样品中叶绿素a、b、c和脱镁叶绿素a的含量,同步观测海水温度、海水密度和pH值。结果显示,青岛近岸春季海水水温上升较快,海水密度和pH比较稳定。栈桥取样点底质中叶绿素a、b、c和脱镁叶绿素a的平均含量分别为0·58、0·47、0·34和0·16μg/g。湛山湾取样点底质中的叶绿素含量最高,波动较小,叶绿素a、b、c和脱镁叶绿素a的平均含量分别为0·72、0·56、0·36和0·45μg/g。石老人海水浴场底质中的叶绿素含量最低,波动较大,叶绿素a、b、c和脱镁叶绿素a的平均含量分别为0·36、0·28、0·20和0·29μg/g。 相似文献
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S. V. Chanda A. K. Joshi P. P. Vaishnav Y. D. Singh 《Journal of Agronomy and Crop Science》1988,160(4):217-223
Fully expanded leaf occupying topmost position in a field grown pearl millet hybrid (BJ-104) and its parents (J-104 and 5141-A) were analysed at weekly intervals for chlorophylls, Hill activity and phosphoenolpyruvate carboxylase activity. Large ontogenic drifts in these parameters, made the actual comparison between hybrid and parents, difficult. However, up to 52 d the hybrid leaf possessed considerably higher chlorophyll pigments than its parents. Amongst the inbreds, the male parent was initially better than the female parent while at later stages, the trend was reversed. Hill activity and PEPcase were more in the male than in the female parent and the hybrid followed the better parent. Rate limiting steps for productivity, measured as NAR (g dry weight)−1 , were worked out in the female parent, using multiple regression and correlation analysis, and the significance of such an analysis is discussed in relation to plant productivity. 相似文献
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黄瓜叶片叶绿素含量近红外光谱无损检测 总被引：3，自引：0，他引：3
为了简化黄瓜叶片叶绿素光谱模型和提高模型预测精度,采用联合区间偏最小二乘法( SiPLS)结合净分析物法( NAS)提取近红外光谱的特征信息,建立了黄瓜叶片叶绿素光谱模型.收集了110片新鲜黄瓜叶片,用近红外光谱仪采集光谱数据后立刻用化学分析方法测定叶绿素含量.原始光谱经过SNV预处理和子区间总数优化后,将全光谱均匀划分为29个子区间,用联合区间偏最小二乘法优选出4个特征子区间,在上述特征子区间的基础上,用净分析物法分离光谱中同叶绿素相关的光谱信息,并结合线性回归法建立了叶绿素光谱模型.模型对应的校正集相关系数Rc、校正均方根误差、预测集相关系数Rp和预测均方根误差分别为0.947 2、0.079 5 mg/g、0.925 0和0.090 6 mg/g.结果表明:联合区间偏最小二乘法结合净分析物法能够有效提取叶绿素的特征光谱信息,提高模型精度的同时降低其复杂度. 相似文献
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Maize (Zea mays L.) seeds of hybrid Ganga‐2 and its parent cultivars were germinated and allowed to absorb Zn labelled ZnCl2 , ZnEDTA or ZnEDDHA for 24 hours. The translocation of Zn in seedlings raised from them was followed on 5, 7 and 10 days. It was found that while the endosperm Zn content decreased rapidly, there was no significant increase in Zn transported to scutellum, root and shoot. There was no difference between Zn treatments as well as between the cultivars. The results demonstrated the poor mobility of Zn in maize during early growth. Further studies showed that the pretreatment of seeds with ZnEDTA and low amount of Fe enhanced chlorophyll content in 10 day old seedlings. No hybrid vigor was observed either in Zn translocation, or effects of Zn and Fe on chlorophyll synthesis. 相似文献
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试验结果表明，返白系返白基因表达与否取决于环境温度，而与光照变化无关。诱导近白基因表达的临界低温值大抵在旬均气温５℃左右，而诱导部位是处于低温临界内的新生叶片的生长部位。 相似文献
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Fruit of Actinidia deliciosa have green flesh when ripe, whereas fruit of Actinidia chinensis often have yellow flesh when ripe. The outer and inner pericarps of A. deliciosa fruit retain their chlorophyll during ripening. In those fruit of A. chinensis that become yellow on ripening, the colour change is caused by the disappearance of chlorophylls unmasking the yellow carotenoids already present, rather than by increased synthesis of carotenoids. In fruit of A. deliciosa and those fruit of A. chinensis that remain green, the chloroplasts retain their typical morphology during ripening, whereas in fruit of A. chinensis that become yellow during ripening the chloroplasts of the immature green fruit are transformed into fully developed chromoplasts. 相似文献
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H2O2 和Ca2+ 对受低温胁迫香蕉幼苗抗冷性的影响 总被引：30，自引：0，他引：30
研究表明, 香蕉幼苗喷施H2O2 或CaCl2 或二者结合使用, 能提高其POD 活性, 降低膜渗漏率, 增加可溶性糖含量及减缓叶绿素降解, 从而提高抗寒力, 二者结合表现出协同效应。H2O2 对提高POD活性, 降低膜渗漏率和减缓Chl. b 降解的效果优于CaCl2 ; CaCl2 则在提高可溶性糖含量和减少Chl. a 降解方面占优。相关性分析表明, POD 活性与膜渗漏率的负相关性达到显著水平, 高POD 活性有利于减少低温下膜渗漏。 相似文献
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Debora Tura Carmen Gigliotti Stefano Pedò Osvaldo Failla Daniele Bassi Arnaldo Serraiocco 《Scientia Horticulturae》2007
Oxidation stability is an important property of olive oil quality and is affected by different antioxidant compounds whose levels may be influenced by cultivar, year and place of production. Polyphenols, tocopherols, carotenoids, chlorophylls and fatty acids levels were correlated to oxidative stability in olive oils from three experiments: cultivar influence (18 cultivars assessed for 4 years in the same place); environmental influence by mesoclimatic (4 cultivars from 17 sites in a single region for 4 years) and macroclimate conditions (3 cultivars from 3 different regions for 3 years). Total polyphenols and saturated on polyunsaturated fatty acids ratio were shown to be the major factors in oil antioxidant stability, according to multivariate regression models. Among the surveyed cultivars, oils from ‘Leccino’ and from three ‘local’, minor cultivars (‘Miniol’, ‘Regina’ and ‘Rossanello’) resulted in higher oxidative stability and oils from cultivars grown in Tuscany (central Italy) showed the highest oxidative stability by comparison with northern and southern regions. 相似文献
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