微胚乳超高油玉米籽粒胚乳消减及油分积累的规律

[目的]研究微胚乳超高油玉米籽粒胚乳消减和油分积累规律。[方法]以高油玉米115为对照,研究2种微胚乳超高油玉米籽粒的胚、胚乳、种皮及相应油分的积累规律。[结果]微胚乳超高油玉米在籽粒发育过程中胚乳干重在发育的第27 d达最大,第37 d消减基本结束;胚的重量一直增加,种子成熟时和胚乳的重量相当;整粒干重第32 d达最大。3个玉米品种授粉后的种皮干重一直增加,第32 d基本稳定,整粒油分37 d前一直增加,之后趋于稳定。微胚乳超高油玉米胚乳的油分在17~27 d增加较慢,27~37 d增加迅速,37 d到成熟期下降,比高油115的高很多;胚的油分在17~27 d增加,27 d到成熟期略下降。高油玉米115胚和胚乳的重量一直增加,胚乳的油分一直很低,胚的油分在17~27 d增加。[结论]该研究为微胚乳超高油玉米的籽粒胚乳消减机理研究提供了参考。     

氮钾硫配方施肥对萝卜产量和硝酸盐含量的影响

为使人们能够吃上健康的无公害食品,采用三因素五水平最优回归设计,探讨了氮钾硫配方施肥对黄泥土萝卜产量和硝酸盐含量的影响。结果表明,萝卜高产和低硝酸盐含量的最佳氮钾硫用量为N 180~200 kg/hm2,K2O 120~150 kg/hm2,S 135~160 kg/hm2。     

白玫瑰挥发油化学成分的研究

本研究采用GC/MS/DS联用技术,分析了白玫瑰花挥发油的化学成分。从分离的的44化合物中,鉴定了41个组分,占挥发油总含量的97.64%。白玫瑰挥发油的主要成分是β—笨乙醇,含量高达86.53%,其次是丁香酚(4.75%)和香叶醇(2.45%)。     

心里美萝卜生长动态和氮磷钾营养吸收特性

 对心里美萝卜生长动态及氮磷钾养分吸收规律的研究表明:播种后37～46 d（肉质根膨大初期）整株鲜、干重增长最快,吸收氮磷钾养分量最多。不同时期吸收量及比例不同。肉质根产量在75 812 kg/hm²时,平均每生产1 000 kg肉质根植株需吸收N 3.49 kg,P 0.39 kg,,K 3.46 kg,比例为1∶0.11∶0.99. 收获时植株吸收的各种养分主要贮存在肉质根中。     

不同氮肥水平下烯效唑对水萝卜产量和品质的影响

采用盆栽试验方法,研究不同氮肥水平下,喷施不同浓度烯效唑对水萝卜产量和品质的影响。结果表明:在不同施氮水平下,烯效唑处理均有利于水萝卜产量的提高,在低氮与高氮水平下,提高幅度分别为7.0%～43.3%和5.0%～24.8%;在增产的同时,烯效唑处理还能有效改善水萝卜的品质,表现为显著提高蛋白质、可溶性糖和维生素C含量,降低体内硝态氮的含量;喷施烯效唑还可以增加水萝卜叶片叶绿素的含量,提高叶片的同化能力。试验条件下,水萝卜达到高产、优质的烯效唑浓度为30 mg/kg。     

Methane fluxes from three ecosystems in tropical peatland of Sarawak, Malaysia

Methane fluxes were measured monthly over a year from tropical peatland of Sarawak, Malaysia using a closed-chamber technique. The CH₄ fluxes in forest ecosystem ranged from −4.53 to 8.40 μg C m⁻² h⁻¹, in the oil palm ecosystem from −32.78 to 4.17 μg C m⁻² h⁻¹ and in the sago ecosystem from −7.44 to 102.06 μg C m⁻² h⁻¹. A regression tree approach showed that CH₄ fluxes in each ecosystem were related to different underlying environmental factors. They were relative humidity for forest and water table for both sago and oil palm ecosystems. On an annual basis, both forest and sago were CH₄ source with an emission of 18.34 mg C m⁻² yr⁻¹ for forest and 180 mg C m⁻² yr⁻¹ for sago. Only oil palm ecosystem was a CH₄ sink with an uptake rate of −15.14 mg C m⁻² yr⁻¹. These results suggest that different dominant underlying environmental factors among the studied ecosystems affected the exchange of CH₄ between tropical peatland and the atmosphere.     

Impacts of chronic marine oil pollution and the murre hunt in Newfoundland on thick-billed murre Uria lomvia populations in the eastern Canadian Arctic

We developed a deterministic and stochastic age-based matrix projection population model to assess and quantify the impact of mortality caused by chronic oil pollution and legal hunting on thick-billed murre Uria lomvia populations breeding and wintering in eastern Canada. We calculate the potential population growth rate in the absence of anthropogenic mortality sources using a modeling technique that translates absolute number of birds killed from anthropogenic mortality to potential survival rates in the absence of these anthropogenic impacts. The intrinsic growth rate of the deterministic matrix based on vital rates from Coats Island (λ_d=1.0102), as well as the stochastic growth rate (λ_s=1.0098, 95% C.I. 0.9969-1.0226), matched observed population trends. Hunting mortality reduced population growth rate by 0.020 (0.012-0.039), oiling mortality reduced population growth rate by 0.025 (0.012-0.039). Combined these sources reduced the population growth rate by 0.047 (0.033-0.610). Although thick-billed murre populations are stable or slowly growing in eastern Canada, anthropogenic sources of mortality are reducing the ability of the population to grow, and increase vulnerability in these populations to changes in their environment and other pulse perturbations. Our modeling technique could be used to assess specific anthropogenic impacts on populations where a vital rates and numbers killed are known, but no long-term trend information is available.     

Combined microbial community level and single species biosensor responses to monitor recovery of oil polluted soil

Understanding the effects of oil contamination on the composition and function of soil microbiota entails investigation of the effects of a mixture of hydrocarbons at the community level in a complex environmental matrix. One approach to this difficult problem is to ally a community-level fingerprinting approach with bioassays that have a physiological or functional implication. Two contrasting refined oils (paraffin and motor oil) were used to contaminate soil microcosms, and a simulated bioremediation treatment with nutrient-addition was applied. The indigenous microorganisms were monitored over 103 d using complementary community-level techniques (carbon source physiological profiling using Biolog^® microplates, and phospholipid fatty acid (PLFA) profiling). Changes in the toxicity of the applied oils were monitored using luminescent bacterial bioassays, including Vibrio fischeri and a hydrocarbon-degrading Pseudomonas putida strain. Distinct shifts in microbial community structure and C source utilization profiles were observed as a result of oil contamination. There was some evidence that bioremediated soils were returning to control values by the end of the experiment. This was supported by the bioassay results which showed an initial increase in toxicity as a result of the oil addition which had then decreased by the conclusion of the experiment. The two oils exhibited markedly different toxicity towards the bioassay organisms, with species-specific differences in response. This oil-specific difference was also found in the PLFA profiles which showed the two oil types selected different microbial communities.     

油用向日葵新葵19号恢复系654R的选育及利用

[目的]研究油用向日葵恢复系的选育方法。[方法]在现有技术中向日葵恢复系的选择过程比较漫长且结果不明确的情况下,为了改变从杂种一代F1以后连续自交的作法,在早代就开始进行测定其配合力,有目的的选择,方向比较明确,提高选择效率,创造新的优异资源。[结果]选育出油用向日葵新葵19号恢复系654R,该恢复系植株性状好、抗病性好、抗逆性强、配合力高、杂种优势强。[结论]该研究提供了一种油用向日葵恢复系新的选育方法,并对654R进行利用。     

包装材料对食用油储藏的影响

采用3种不同的包装形式进行食用油储藏,考察不同包装材料对食用油储藏指标的影响.试验得出,在50℃干燥箱贮藏过程中,不同包装材料灌装的大豆油油样指标变化程度由低到高依次为:玻璃瓶装、PET装、软包装复合食品袋装.可以看出,玻璃瓶对油样的贮藏效果最好.为保持食用油品质,可加入限量的抗氧化剂来弥补包装材料的差异.