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101.
Fernando González-Andrés Pedro A. Casquero Cristina San-Pedro Elías Hernández-Sánchez 《Genetic Resources and Crop Evolution》2007,54(1):27-44
All the accessions (35) of white lupin (Lupinus albus L.) landraces collected from northwest Iberian plateau and maintained at the Spanish germplasm collection (CRF of INIA),
were studied with the general objective of assessing the biodiversity of these landraces and to ascertain their value as genetic
resources for the development of germplasm adapted to the areas where they were collected with long and chilly winters. The
characterization study comprised 51 qualitative and 50 quantitative characters. Quantitative parameters were analyzed by Principal
Components Analysis (PCA). The 2-dimensional plot (49.3% of cumulative variability) formed a main group of accessions and
4 outliers (#1, #9, #27 and #28) separated in the first PC. The characters with a higher contribution to the first PC were
inflorescence length, leaf petiole length and leaf central foliole area. The presence of alkaloids, the percentage of plants
killed by soil borne fungal diseases, the phenology, the yield per plant and yield components were also assessed. Twenty six
accessions (the main group in the PCA plot) showed high homogeneity, with the following highlights: bitterness, indeterminate
growth habit, early ripeness and spring sowing with the exception of #18, in which seeding date is unknown and it had a later
phenology. By contrast accessions #9 and #27 were bitter of autumn sowing with determinate growing habit and they had the
longest values of primary inflorescence length and a later phenology when they were sown in spring. Average values for yield
and yield components showed a broad range of variation between accessions. The main yield component was the number of pods
per plant. Accession #22 had the highest mean seed mass, although this had not significant influence in yield. Accession #17
showed the highest yield and #1 the lowest. This last also had the lowest values of inflorescence length, leaf petiole length
and leaf central foliole area. No significant differences of resistance to soil-borne fungi were found between accessions.
The year had a significant effect in the phenology, yield and yield components except for number of seeds per pod. The studied
material might be of interest for the development of spring sowing germplasm adapted to north Iberian peninsula. 相似文献
102.
Ilyas Siddique Caroline Gutjahr Gamini Seneviratne Broder Breckling Sudheera W. Ranwala Ian J. Alexander 《Biology and Fertility of Soils》2007,44(1):163-170
Topsoil properties were determined in forest gardens established about 20 years ago on eroded grassland soils (abandoned tea
lands) in the wet zone of the Sri Lankan highlands. They were compared with adjacent, eroded grasslands (abandoned tea lands)
on strongly weathered soils vs soils at earlier stages of pedogenic development in a two-way analysis of variance. Soil pH
in forest gardens was, on average, 6.1, nearly one unit higher than in the adjacent grasslands. In the garden soils, the cation
exchange capacity (CEC measured at pH 4.8) was nearly double, exchangeable calcium concentrations five times and exchangeable
magnesium three times as high as in the grasslands soils. Total soil N content was found to be nearly 40% higher in the gardens.
Topsoil gravel contents in the gardens were less than half as high as in the grasslands. The increases in exchangeable bases
and N in gardens, relative to grasslands, were attributed to increased nutrient retention and acquisition. Higher retention
was partly due to the higher CECpH4.8, and probably to reduced erosion and increased, continuous fine root density in the garden topsoils. Higher field CEC in
gardens was likely to result from generally higher C contents and from the reversal of acidification, presumably caused by
base accumulation and decomposition processes. Our results suggest that forest garden establishment on degraded grasslands
can lead to accumulation of mobile nutrients in the topsoil, probably due to increased nutrient retention, subsoil uptake
and litter input exceeding nutrient uptake by the standing biomass. 相似文献
103.
Huang GJ Sheu MJ Chen HJ Chang YS Lin YH 《Journal of agricultural and food chemistry》2007,55(15):6000-6006
Peroxynitrite (ONOO-), formed from a reaction of superoxide and nitric oxide, is one of the most potent cytotoxic species known to oxidize cellular constituents including essential proteins, lipids, and DNA. ONOO- induces cellular and tissue injury, resulting in several human diseases such as Alzheimer's disease, atherosclerosis, and stroke. Due to the lack of endogenous enzymes responsible for ONOO- scavenging activity, finding a specific ONOO- scavenger is of considerable importance. In this study, the ability of trypsin inhibitor (TI), isolated from sweet potato storage roots (SPTI), to scavenge *ON and ONOO- was investigated. The data obtained show that TI generated a dose-dependent inhibition on production of nitrite and superoxide radicals. The IC50 value of TI on superoxide radical was 143.2 +/- 4.29 microg/mL. SOD activity staining was used to confirm SOD activity of SPTI. SPTI also caused a dose-dependent inhibition of the oxidation of dihydrorhodamine 123 (DHR) by peroxynitrite. A calculated IC50 value of 809.1 +/- 32.36 microg/mL was obtained on the inhibition of peroxynitrite radical. Spectrophotometric analyses revealed that TI suppressed the formation of ONOO--mediated tyrosine nitration through an electron donation mechanism. In further studies, TI also showed a significant ability to inhibit nitration of bovine serum albumin (BSA) in a dose-dependent manner. In vivo TI inhibited lipopolysaccharide-induced nitrite production in macrophages in a concentration-dependent manner with an IC50 value of 932.8 +/- 29.85 microg/mL. The present study suggested that TI had an efficient reactive nitrogen species scavenging ability. TI might be a potential effective NO and ONOO- scavenger useful for the prevention of NO- and ONOO--involved diseases. 相似文献
104.
茶树油清除豇豆农药残留的效果 总被引:1,自引:0,他引:1
为研究茶树油清除果蔬农药残留的效果,该试验选取豇豆为供试材料,以不同浓度的茶树油和水溶性茶树油等清洗处理,利用气相色谱和气相色谱-质谱联用检测豇豆内有机磷类、拟除虫菊酯类和氨基甲酸酯类的农药残留量,计算农药清除率。供试7种农药中,水胺硫磷、马拉硫磷、氧乐果、三唑磷、毒死蜱、氯氰菊酯和速灭威在豇豆中的初始浓度分别为:20.395、1.690、6.524、10.719、0.160、12.104和23.057mg/kg。茶树油处理后检测结果表明,茶树油具有清除残留在豇豆中农药的能力,清除效果随茶树油浓度增加而增强;清除有机磷类农药效果较拟除虫菊酯类和氨基甲酸酯类农药明显。茶树油比去离子水、市售果蔬农残清洗剂清除农药残留效果显著,同时,相同浓度的水溶性茶树油比相应茶树油清除农药残留能力强。0.8%水溶性茶树油清除效果最佳,清除率分别为水胺硫磷80.48%,马拉硫磷94.54%,三唑磷82.79%,毒死蜱84.58%,氧乐果72.20%,氯氰菊酯80.51%,速灭威72.21%。通过研究结果可知,茶树油可作为有开发前景的果蔬清除剂。 相似文献
105.
为恢复和保护濒危淡水贝类资源,该文根据物质平衡原理,以具有代表性的淡水彩虹贝类为研究对象,设计并构建了一套小型的室内淡水彩虹贝循环水养殖系统,该系统由养殖池、生物过滤器、蓄水池、循环水泵、充氧系统和自动投饵装置等环节组成。并在该循环水系统中对钩介幼虫2日龄的彩虹贝幼贝进行了为期60 d的养殖(2011年6月21日到2011年8月20日),整个养殖周期内,彩虹贝幼贝养殖系统环境稳定,水质稳定良好,彩虹贝幼贝壳长日增长量为15.2μm/d,彩虹贝幼贝的最大相对增长率发生在第40天到第50天,其相对生长率为32.4%,和之前池塘流水、跑道式等养殖模式相比,该循环水系统养殖的彩虹贝幼贝获得了更高的生长率。该研究可为淡水贝类的人工繁育和养殖提供参考。 相似文献
106.
快速脱水抑制葡萄干制过程中膜脂过氧化及褐变 总被引:1,自引:1,他引:1
为探索脱水速度对无核白葡萄干制过程中膜脂过氧化作用及褐变的影响,以新疆无核白葡萄为试验材料,经过葡萄促干剂处理后,采用快速脱水和缓慢脱水2种处理,质量每减轻10%进行取样,测定脱水过程中果实干基含水率、干燥速率、褐变度、细胞膜透性、丙二醛(malonaldehyde,MDA)含量、脂氧合酶(lipoxygenase,LOX)、超氧化物歧化酶(superoxide dismutase,SOD)、过氧化氢酶(catalase,CAT)、过氧化物酶(peroxidase,POD)、多酚氧化酶(polyphenol oxidase,PPO)活性以及总酚含量的变化。结果表明:与缓慢脱水相比,快速脱水处理显著(P0.05)降低了无核白葡萄褐变度的上升,减少MDA生成量以及膜透性的增加,抑制LOX活性的升高,保持较高的活性氧清除酶SOD、CAT及POD活性及较高的总酚含量,且使PPO活性保持在一个较低的水平。因此认为,快速脱水可以有效地抑制无核白葡萄的膜脂过氧化作用对细胞膜的破坏,保持细胞的完整性,且PPO活性较低,从而减少无核白葡萄脱水褐变的发生。研究结果为快速脱水在无核白葡萄干制中的应用提供参考。 相似文献
107.
不同种植方式对红壤旱地土壤水分及抗旱能力的影响 总被引:1,自引:0,他引:1
通过3年田间小区试验,研究不同种植方式对红壤旱地土壤水分及抗旱能力的影响.结果表明:1)与种植花生相比,种植苎麻可显著提高土壤有机质质量分数(28.44%)、田间持水量(10.06%)和总孔隙度(5.65%),土壤密度则显著降低7.20%;2)监测期内,花生地各层土壤以及整个0~ 100 cm土体水分变异系数普遍高于苎麻地,苎麻地0 ~ 100 cm土体水分的时间稳定性和空间协调性优于花生地;3)苎麻地0~ 40 cm土壤较花生地延长抗旱时间7d以上,但随着土层的加深,差异越来越小;4)红壤坡耕地种植苎麻有利于提高红壤旱地土壤抗旱能力,特别是中、上层土壤.从扩充土壤水库的角度考虑,红壤旱地种植苎麻优于种植花生,该研究结果可为挖掘红壤区深层土壤水分提供参考. 相似文献
108.
109.
Compressed wooden plates and dowels were used to connect members in post-and-beam structures as a substitute for a steel fastener.
In order to take advantage of the characteristic properties of compressed wood and to achieve optimum joint performance, two
compressed wooden plates were used in each joint to give multiple shear planes for each compressed wooden dowel. Consequently,
this type of joint showed very good properties in pull-out and momen-trotation performance, and its engineering design could
be further optimized. This joint is expected to be introduced to many kinds of structural systems, including long-span frame
structures made of domestic timber found in Japanese residential houses. 相似文献
110.
Xu Jun-liang Ma Lv-yi 《中国林学(英文版)》2007,9(4):251-255
In order to explore the relationship between the time processes of solar radiation and sap flow, sap flow velocity (SFV) of Platycladus orientalis and Pinus tabulaeformis, effective solar radiation (ESR) and other environmental factors were synchronously monitored for one year in the Beijing Western Mountains by using a thermal dissipation probe (TDP) system and an automatic weather station. Results showed significant differences between changes in diurnal characteristics of ESR and sap flow in sunny days during three seasons. Starting times of sap flow occurred generally 1.5–3 hours later than those of solar radiation and there were small differences between Platycladus orientalis and Pinus tabulaeformis. But peak times and stopping times of sap flow varied con-siderably with large contrasts in ESR. The duration of sap flow showed clear differences among the seasons owing to the variable rhythms of climate factors in Beijing. Fluctuation amplitude in the duration of sap flow remained relatively stable during the autumn but changed greatly during spring and summer. Changes in diurnal sap flow velocity of both Platycladus orientalis and Pinus tabu-laeformis were about 0–3 hours later than those of ESR but with the same configuration. The start of sap flow was mainly induced by the sudden intensification of ESR (sunrise effect). Seasonal models of SFV indicated that a cubic equation had the best fit. It was more practical to simulate seasonal water consumption models of trees with ESR. In further investigations, these models should be optimized. 相似文献