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31.
通过对糯米糍荔枝叶片、果皮、土壤中矿质元素含量的研究,探讨矿质营养对荔枝裂果率的影响。初步探明糯米糍荔枝叶片中的钙、镁、硼含量,果皮中的氮钾比,以及土壤中的N/K比、有机质、交换性钙含量影响其裂果率。 相似文献
32.
Iride Passarella Irene Elia Barbara Guarino Giancarlo Bourlot Michèle Nègre 《Journal of environmental science and health. Part. B》2013,48(2):137-143
The dissipation of the fungicides captan, cyprodinil, fludioxonil, dithianon, and tebuconazole and of the insecticides chlorpyrifos, fenitrothion, and malathion was studied, following a single treatment of different cultivars of pears, apples, and peaches. The study was conducted in northern Italy, over two successive growing seasons (2004 and 2005). The treatments were performed by the farmers involved, in line with their usual practice. At various time intervals from treatment to harvest, representative samples of fruit were collected and analyzed for pesticide residues. In some cases, concentrations lower than the maximum residue levels (MRLs) were found immediately after treatment. In all trials a rapid decline in pesticide concentrations was observed leading to residues at harvest greatly below the MRLs. 相似文献
33.
SYLVAIN GLÉMIN† CHRISTOPHE PETIT† SANDRINE MAURICE† AGNÈS MIGNOT† 《Conservation biology》2008,22(1):216-221
Abstract: Self-incompatibility systems prevent self-fertilization in angiosperms. Although numerous S alleles are usually maintained by negative frequency-dependent selection, the number of S alleles can be low in small populations, which limits mate availability and reduces fecundity in endangered populations of self-incompatible plants. Despite the increasing evidence of the negative effect of self-incompatibility in small populations, the direct link between the number and the distribution of S alleles and their reproductive consequences has been rarely reported. Brassica insularis is a rare self-incompatible species with medium to very small populations. Results of a previous study showed that the smallest population has very few S alleles. We investigated whether reduced mate availability affects reproduction in this species. We compared the pollination success and the fruit set in 4 populations differing in population size and number of S alleles. Our results suggest that reproduction may be negatively affected by the low S-allele diversity in the smallest population. Nevertheless, other populations also had reduced fruit set that could not be attributed to self-incompatibility alone. 相似文献
34.
R.P. Singh A. EmbrandiriM.H. Ibrahim N. Esa 《Resources, Conservation and Recycling》2011,55(4):423-434
Solid waste management is one of the challenging problems worldwide and it is becoming more complex by the increase in population and subsequently the waste generated. In Malaysia, among industrial solid waste palm oil mill waste (POMW) contributes the highest share. Wastes from the oil palm mill includes palm oil mill effluent (POME), decanter cake, empty fruit bunches, seed shells and the fibre from mesocarp. Generally most of the waste generated is either disposed of via open dumping or used as fertilizers as such or as animal feed. Land application of POMW and POME is very common practice as it contains numbers of plant nutrients. Direct application of POMW into agricultural soil can result in a number of problems such as water pollution, leaching etc. To deal with these problems, vermicomposting of palm oil mill waste may be a sustainable waste management option.There are number of researches going on management of biomass residues from palm oil mill, but very few works are going on vermicomposting of these agro-industrial waste. Vermicomposting of POMW can be a good practice as it will also be helpful in recycling the useful plant nutrients and it is better than that of composting process. Present review deals with the various aspects of vermicomposting of POMW and its importance. Review also put forward the effect of potential application of vermicompost on plant growth. On the whole it looks for the possibility of vermicomposting of waste from palm oil mill as a sustainable waste management alternative. 相似文献
35.
36.
攀西地区果树资源开发研究 总被引:2,自引:0,他引:2
攀西地区光热资源丰富,集南北果树于一地。从商品化、规模化的要求出发,规划,构建该区果树树种的合理布局和良种结构,培养发展果品市场和技术市场是攀西地区果品上新台阶的重要途径。 相似文献
37.
汤立志 《湖南环境生物职业技术学院学报》2006,12(4):356-359
通过对果树注射施肥技术原理,特点与操作方法的介绍,并与传统的方法相对比.从果品产量与品质,肥料利用率,环境影响程度等方面分析了果树注射施肥的效果,该方法具有较大的推广应用前景. 相似文献
38.
为实现边坡危险性及时预警预报,以露天矿边坡变形量为研究对象,提出采用七项影响指标作为边坡位移变形量的响应参数,建立支持向量机回归预测模型(SVR)。引入修正的果蝇优化算法(MFOA)对模型参数进行优化,构建基于MFOA-SVR露天矿边坡变形量协同预测模型,并以实际监测数据进行模型仿真预测。结果表明:该模型平均绝对误差为0.9167mm,平均相对误差为4.2737%,较其他模型预测精度高,综合性能好,将其运用于露天矿边坡变形量预测研究具有较好的适用性和可靠性。 相似文献
39.
镉胁迫对不同砧穗组合葡萄植株镉吸收规律和果实品质的影响 总被引:1,自引:0,他引:1
以3年生盆栽不同砧穗组合葡萄植株为供试材料,加入氯化镉(CdCl2)以模拟成15mg·kg-1Cd2+的Cd污染土壤,研究镉在不同砧穗组合葡萄植株内的吸收和分配规律以及对果实品质的影响。结果表明:Cd在不同组合葡萄植株的积累浓度由高到低顺序均为:根系〉茎〉叶片〉果实,不同组合葡萄植株镉含量和果实品质存在显著的差异。所有葡萄植株的果实Cd积累质量分数均低于我国绿色食品Cd限量标准(0.03mg·kg-1,FW),然而自根苗果实Cd质量分数(0.028mg·kg-1,FW)非常接近0.03mg·kg-1FW,嫁接葡萄植株果实的Cd含量均显著低于自根苗,大约为自根苗的20%~86%,Y/华佳8号、Y/SO4和Y/5BB葡萄果实的Cd含量较低。嫁接降低了葡萄果实中的Cd含量,从一定程度上减轻了人类的Cd暴露风险。不同组合葡萄植株果实的品质存在差异,嫁接提高了Cd胁迫下葡萄果实的可溶性糖(Y/SO4除外)和花青苷含量,降低了可滴定酸含量,提高了果实品质。 相似文献
40.
M. Inés Toral Pablo Richter Mónica Cavieres Walter González 《Environmental monitoring and assessment》1999,54(2):191-203
A simple method by first derivative spectrophotometry is proposed for the simultaneous determination of o-nitrophenol and p-nitrophenol. The analytes were separated from samples by liquid-liquid extraction (pH = 7.4) as tetrabutylammonium ion pairs into the 1,2-dichloroethane organic phase and subsequently the extracts were evaluated directly by derivative spectrophotometry. Simultaneous determination of both analytes could be carried out using the zero-crossing and the graphical methods for o-nitrophenol and p-nitrophenol, respectively. The determination ranges were found to be between 0.115 to 3.00 ppm and 0.130 to 3.00 ppm for o-nitrophenol and p-nitrophenol, respectively. The relative standard deviations were in all instances less than 2.0%. The proposed method was applied to the determination of these compounds in fruit juices. 相似文献