硫酸锰溶液处理对玉米种子抗氧化酶活性的影响

Two kinds of corn were used as materials,changes of SOD,CAT,POD and MDA Contents after Germination of maize seeds in five different concentrations of manganese sulphate were studied.The results show that the content of MDA was significantly different among different varieties,difference was very significant compared with control.The activities of antioxidant enzymes of HuangJinNuo 1 first increased then decreased after treated with manganese sulfate,while that of YinLong BaiYuNou continuous elevation,the resistance of Maize after manganese sulphate increased during germination.     

Investigation of environmental and land use impacts in forested permafrost headwaters of the Selenga-Baikal river system,Mongolia - Effects on discharge,water quality and macroinvertebrate diversity

Headwater streams play a major role for provision of ecosystem services, e.g. drinking water. We investigated a high-altitude headwater catchment of the Kharaa River (including 41 1st-order rivers) to understand the impact of land cover (especially forest cover), environment and human usage on runoff, chemical water quality and macroinvertebrate fauna in a river basin under discontinuous permafrost conditions in an arid, sparsely populated region of Mongolia. To verify our hypotheses that different landuses and environmental impacts in permafrost headwaters influence water quality, we investigated 105 sampling sites, 37 of them at intermittent stream sections without water flow. Discharge was positively impacted by land cover types steppe, grassland and forest and negatively by shrubland, forest burnt by wild fires (indicating a reduction of permafrost) and slope. Water quality was affected by altitude, longitude and latitude, shrub growth and water temperature. Shannon diversity of macroinvertebrates was driven by water temperature, iron content of the water, flow velocity, and subbasin size (adjusted R² = 0.54). Sample plots clustered in three groups that differed in water chemistry, macroinvertebrate diversity, species composition and bio-indicators. Our study confirms that steppes and grasslands have a higher contribution to runoff than forests, forest cover has a positive impact on water quality, and diversity of macroinvertebrates is higher in sites with less nutrients and pollutants. The excellent ecological status of the upper reaches of the Kharaa is severely threatened by forest fires and human-induced climate change and urgently needs to be conserved.     

生长调节物质对小豆豆芽营养成分影响和功能性评价

为筛选最适合芽菜培养的小豆品种,以‘白红8号’为试材,设置3种生长调节物质(乙酰水杨酸、乙烯利和6-苄氨基腺嘌呤(6-BA))的各6个浓度(0.0、0.1、0.2、0.3、0.4、0.5 mmol/L;0、20、30、40、50、60 mg/L和0、2、3、4、5、6 mg/L)喷施处理,测定其生物特性(上胚轴长度、上胚轴直径、萌发率、鲜重、干重和产出比)、营养成分(可溶性蛋白和可溶性糖)及抗氧化等特性。结果表明:3种生长调节物质喷施处理都能够提升其营养价值,在乙烯利喷施浓度为50 mg/L,‘白红8号’小豆芽苗菜中各营养成分、酶活性及抗氧化性等均可达到最大值,显著提高了其营养价值。因此,为提高生产中小豆芽苗菜的产量和营养价值,最终确定乙烯利喷施浓度为50 mg/L效果最佳。     

Hydrodynamic method for estimating production carrying capacity of coastal finfish cage aquaculture in Southeast Asia

This paper presents the development of a simple and generally applicable hydrodynamic method for the estimation of production carrying capacity (PCC) of coastal finfish cage aquaculture. Dimensional analysis was used to find significant and general interdependencies between the hydrodynamics at fish farm locations and particulate wastes deposited on the seafloor by fish farms. Modeled ratios of deposition to emission of particulate wastes underneath fish farms were found to be primarily a function of the flow Reynolds numbers at the farming locations and the non-dimensional settling velocity of emitted wastes. In the non-dimensional model, farming conditions include daily feed rate, proportion of unconsumed feed, and carbon content in feed and fish feces. The relationship can be used to estimate the PCC of floating net cages imposing a threshold value for deposition. Results of in-situ assessments of the benthic impacts of several fish farms in an aquaculture site in the northwest of Bali, Indonesia were used to validate and demonstrate the effectiveness of the method. Predicted results were able to clearly identify fish farms operating beyond ecologically sustainable carrying capacity. The proposed method has broad applicability and could help make decisions regarding the estimation of production potential of individual farms in pristine areas, for providing first estimates in sites that have scarce data, and for assessment, expansion, and optimization of the currently operating aquaculture sites in Southeast Asia, China and potentially other data-poor island nations. As the method relies on dynamic models, it enables straightforward assessments over the entire aquaculture region.     

Crude garlic extract significantly inhibits replication of grapevine viruses

Efforts to control viral diseases of grapevine include the production of certified material and development of virus-resistant transgenic grapevines. However, effective antiviral agents, once the viruses have infected the plants, are still lacking. This study shows that a crude garlic extract has significant antiviral activity against grapevine viruses. Replication of grapevine leafroll-associated virus 2 (GLRaV-2) was obviously inhibited in grapevine cv. Cabernet Sauvignon calli treated with diluted (1:100) garlic extract. The relative RNA levels of GLRaV-2 and grapevine fleck virus (GFkV) in cv. Summer Black grapevine in in vitro-grown plantlets 10 days after treatment with diluted (1:100) garlic extract were about 22% and 20%, respectively, of that in controls. The viral RNA accumulation of GLRaV-2, GFkV, grapevine virus A (GVA), grapevine fanleaf virus (GFLV) and grapevine rupestris stem pitting-associated virus (GRSPaV) in field-grown grapevine cv. Centennial Seedless plants sprayed with diluted (1:100) garlic extract were about 31–40%, 26–38%, 18–31%, 17–42% and 15–18%, respectively, of that in controls. Moreover, the garlic extract treatment led to a significant decrease in viral RNA accumulation of GLRaV-3, GLRaV-2, GVA, GFkV, GFLV, GRSPaV and grapevine Pinot Gris virus in pot-grown grapevine cv. Shine Muscat plants, and viral disease symptoms in these plants were obviously attenuated. In addition, this extract significantly induced expression of pathogenesis-related protein genes and stimulated activity of antioxidant enzymes in grapevines. Taken together, these results indicate that the crude garlic extract acts as a significant inhibitor against a broad range of grapevine viruses.     

面包面团发酵性能研究

面团的发酵性能直接影响面包的品质,本研究考察了酵母、糖和食盐用量对面包面团发酵性能的影响,分析了面团在发酵过程中pH值和体积的变化。通过试验发现,面团的发酵速度与酵母和糖的用量成正比,但是过多的酵母和糖均会降低面团的持气性;加入一定的食盐会抑制面团的发酵,而适量的食盐却能在一定程度上改善面团的持气性。通过酵母、糖、食盐的配比试验发现,当酵母添加量为1.0%、糖添加量为10%、盐添加量为10%时,面包面团具有最佳的发酵效果和持气性。     

Orange peel fragment improves antioxidant capacity and haematological profile of Nile tilapia subjected to heat/dissolved oxygen‐induced stress

This study evaluated the ability of orange peel fragment (OPF) to act as a functional feedstuff, influencing growth, haematological profile, and antioxidant enzyme activity of Nile tilapia subjected heat/dissolved oxygen‐induced stress (HDOIS). A group of 440 male Nile tilapia (31.7 g ± 0.34) was randomly distributed in 40 250‐L aquaria (11 fish/tank) and fed five practical diets with graded levels of OPF at 0%, 0.2%, 0.4%, 0.6%, and 0.8% for 70 days. The diets were formulated to contain 30% crude protein and 18 MJ/kg crude energy. After the feeding period, growth performance was evaluated and six fish per treatment were sampled for haematological profile and antioxidant enzyme activity, before and after HDOIS. Then, fish were subjected to HDOIS (32°C/2.3 mg/L dissolved oxygen) for three days and the same haematological profile and antioxidant enzyme activity were determined. There was no effect of OPF on the haematological profile, either before or after HDOIS. The polynomial regression model was used to express the relationship between antioxidant enzymes activity and OPF supplementation level. The maximum activity of superoxide dismutase, catalase, and glutathione peroxidase was reached at 0.66%, 0.63%, and 0.68% of OPF respectively. Results of the present study suggest that a dietary supplementation level of 0.63%–0.68% of orange peel fragment was appropriate to maintain Nile tilapia haematological profile and improve its antioxidant capacity under HDOIS.     

油菜素内酯浸根对水稻水卷苗机插植伤的修复效应

目的 探究油菜素内酯(Brassinolide, BR)浸根对机插水卷苗栽后本田生长及产量的影响。方法 以宁粳8号为试验材料,分析不同浓度BR(T1、T10、T20,分别表示水培营养液中BR浓度为1 mg/L、10 mg/L、20 mg/L)浸根对水卷苗机插本田后返青活棵及产量的影响,以正常水培营养液处理为对照(CK)。结果 BR浸根(T1、T10、T20)能够促进水稻地上部生长,栽插本田21d后株高较CK分别增加11.68%、8.12%和7.61%;BR浸根对水卷苗栽后根系的促生作用更为明显,不同浓度BR浸根对水卷苗栽后根长、根表面积、根尖数、根体积、根直径、根质量和根冠比均产生了显著影响,其中根尖数以低浓度BR处理效果更优,而其他根系指标均以高浓度BR处理效果更优。与CK相比,不同浓度BR浸根降低了叶片过氧化氢浓度(至移栽后12 d,分别降低12.50%、23.25%和22.25%),增强了叶片抗氧化酶活性;与移栽当天相比,移栽后第2天BR浸根处理叶片中玉米素(ZT)浓度迅速增加(分别为197.27%、153.11%和243.78%),而CK增加缓慢(2.94%),根系表现一致,且根系中生长素(IAA)浓度显著高于CK;同时BR处理在栽后一周内赤霉素(GA₃)浓度均明显高于对照。与CK相比,T10处理显著提高了每穗粒数和结实率(分别为15.04%和6.62%),T20处理显著提高了结实率(6.17%),但BR处理千粒重均显著下降,最终产量T10和T20处理较CK分别提高5.11%和7.99%。结论 适当浓度的BR(T10~T20)浸根能减轻水卷苗机插植伤,提高抗氧化酶活性,降低H₂O₂含量,提高ZT、GA₃和IAA浓度,高效地促进根系生长,提高了每穗粒数和结实率。本研究可为减轻机插植伤,促进机插水稻高产稳产提供理论依据和技术参考。     

玉米叶片表皮蜡质相关性状的全基因组关联分析

为发掘玉米叶片表皮蜡质合成与调控相关基因，以218份由温带、亚热带和热带自交系组成的关联群体为材料，在原阳对其3个生物学重复叶片表皮挂水能力进行调查，利用1.25 M覆盖玉米全基因组的SNPs进行Q、K和Q+K这3种模型下的全基因组关联分析。结果表明，Q模型较K模型和Q+K模型能更好地评价叶片表皮的挂水能力。Q模型下，共检测到88个覆盖玉米9条染色体的显著SNPs（P ≤ 2.04E-6），88个SNPs分布于47个QTLs内，单个QTL可解释13.6%~45.6%的叶片挂水能力表型变异，47个QTL内共有97个候选基因，其中，77个具有功能注释。位于第2染色体上的转录因子NAC77（GRMZM2G018436）和第3条染色体上的亚油酸酯氧合酶（GRMZM2G156861）编码基因，是叶片表皮蜡质性状的重要候选基因。