茶树品种对侧多食跗线螨种群的影响

研究结果表明:侧多食跗线螨种群在各品种上的田间密度有明显差异,平均螨量早白尖上最多,906最少。室内该螨在各品种上的发育历期、产仔动态、增长速度、生命参数均有明显差异。雌成螨历期蜀永3号最长,蜀永1号最短;产卵数以早白尖最多,906最少,内禀增长率蜀永3号最大,蜀永1号和906最小。因此,蜀永1号和906抗螨性强,蜀永3号抗螨性弱。     

Modeling temporal progress of plant diseases

A model for describing temporal progress of plant diseases is presented. The model (termed a ‘mixed’ model) coincides in two special cases with the logistic and the monomolecular models introduced by Vanderplank. The mixed model is implemented using some data available on the spread of zucchini yellow mosaic virus (ZYMV) from a field experiment in Israel.     

不同体色瓜蚜耐药性差异及其生化机制

试验结果表明,在黄瓜上的绿色瓜蚜(Aphis gossypii Glov.)种群对氧化乐果、抗蚜威和氰戊菊酯的耐性明显高于黄色瓜蚜种群。这两种颜色的瓜蚜乙酰胆碱酯酶(ACHE)具有明显的不同,在绿色种群中,有60.7%的个体AChE活性大于0.8(OD_(412)/mg蛋白质,分钟),而在黄色种群中则仅有25.3%的个体AChE活性大于0.8;氧化乐果(终浓度为1.69×10~(-2)mol/L)对单个蚜虫AChE的抑制率,前者仅有19%的个体AChE抑制率在30%以上,而后者则有46%的个体在30%以上。α-乙酸萘酯羧酸酯酶的活性大于25(×10~(-2)μmol/蚜,15分钟)的个体在绿色种群中占56%,而在黄色种群中仅有20%;β-乙酸萘酯羧酸酯酶活性大于25(×10~(-2)μmol/蚜,15分钟)的个体在绿色瓜蚜中占45%,而在黄色种群中仅有7%。说明绿色和黄色瓜蚜耐药性的差异可能是由于AChE敏感性和羧酸酯酶活性的不同造成的。     

陕西关中梨茎蜂生活史及成虫发生动态

为明确陕西关中酥梨产区梨茎蜂的发生规律,为有效防治提供依据,2019年-2021年,通过田间定期取样结合黄色粘虫板监测,系统调查了梨茎蜂生活史和成虫发生动态。结果表明,梨茎蜂在陕西关中一年发生1代,以老熟幼虫在梨树被害枝条内越冬。春季梨芽萌动时,梨茎蜂越冬幼虫开始化蛹,3月中旬成虫陆续羽化出枝,3月中下旬达到高峰,雌蜂造成的折梢高峰期紧随成虫发生高峰期;4月下旬幼虫为害枝梢髓部,8月下旬幼虫老熟后在被害枝条内越冬。黄色粘虫板不仅诱杀梨茎蜂成虫,同时也诱杀蜜蜂、瓢虫、草蛉、食蚜蝇和寄生蜂等有益昆虫。因此,应抓住梨茎蜂出枝盛期诱杀防治,一旦成虫数量大幅降低,及时解除黄板。     

Quantifying inherent predictability and spatial synchrony in the aphid vector Myzus persicae: field-scale patterns of abundance and regional forecasting error in the UK

Background

Sugar beet is threatened by virus yellows, a disease complex vectored by aphids that reduces sugar content. We present an analysis of Myzus persicae population dynamics with and without neonicotinoid seed treatment. We use 6 years' yellow water trap and field-collected aphid data and two decades of 12.2 m suction-trap aphid migration data. We investigate both spatial synchrony and forecasting error to understand the structure and spatial scale of field counts and why forecasting aphid migrants lacks accuracy. Our aim is to derive statistical parameters to inform regionwide pest management strategies.

Results

Spatial synchrony, indicating the coincident change in counts across the region over time, is rarely present and is best described as stochastic. Uniquely, early season field populations in 2019 did show spatial synchrony to 90 km compared to the overall average weekly correlation length of 23 km. However, 70% of the time series were spatially heterogenous, indicating patchy between-field dynamics. Field counts lacked the same seasonal trend and did not peak in the same week. Forecasts tended to under-predict mid-season log₁₀ counts. A strongly negative correlation between forecasting error and the proportion of zeros was shown.

Conclusion

Field populations are unpredictable and stochastic, regardless of neonicotinoid seed treatment. This outcome presents a problem for decision-support that cannot usefully provide a single regionwide solution. Weighted permutation entropy inferred that M. persicae 12.2 m suction-trap time series had moderate to low intrinsic predictability. Early warning using a migration model tended to predict counts at lower levels than observed. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Effects of Dietary Tributyrin on Growth Performance,Serum Biochemical Indices,Immune Function and Antioxidant Capacity of Juvenile Yellow Catfish (Pelteobagrus fulvidraco)北大核心CSCD

This experiment was conducted to investigate the effects of dietary tributyrin on growth performance, serum biochemical indices, immunity function and antioxidant capacity of juvenile yellow catfish (Pelteobagrus fulvidraco). A total of 480 juvenile yellow catfish with an initial body weight of (5.53±0.02) g were selected and randomly divided into 4 groups with 3 replicates in each group, and 40 fish in each replicate. Four isonitrogenous and isolipid experimental diets were fed with 0 (G0), 500 (G1), 1 000 (G2) and 2 000 mg/kg (G3) triglyceride, respectively. The experiment lasted for 56 days. The results showed as follows: 1) weight gain rate and feed efficiency rate in G2 group were significantly higher than those in other groups (P<0.05). The fatness in G1 group was significantly lower than that in G0 and G3 groups (P<0.05), but there was no significant difference between G1 group and G2 group (P>0.05). 2) The serum glucose content in G3 group was significantly higher than that in G1 and G2 groups (P<0.05), and there were no significant differences in the serum contents of total protein, albumin, globulin, triglyceride, urea nitrogen and the activities of alanine aminotransferase and aspartate aminotransferase among all groups (P>0.05). 3) Compared with G0 group, serum lysozyme activity in G1, G2 and G3 groups was significantly increased (P<0.05), serum alkaline phosphatase activity in G1 and G2 groups was significantly increased (P<0.05), and serum immunoglobulin M content in G2 group was significantly higher than that in G3 group (P<0.05). There was no significant difference in serum complement C3 content among all groups (P>0.05). 4) Compared with G0 group, serum total antioxidant capacity in G1 group was significantly increased (P<0.05), and serum super-oxide dismutase activity in G1, G2 and G3 groups was significantly increased (P<0.05). The serum catalase activity in G3 group was significantly higher than that in G0, G1 and G2 groups (P<0.05), but there were no significant differences in serum glutathione peroxidase activity, glutathione and malondialdehyde contents among all groups (P>0.05). In conclusion, dietary supplementation of 500 to 2 000 mg/kg triglyceride can significantly improve non-specific immune and antioxidant capacity of yellow catfish, and dietary supplementation of 1 000 mg/kg triglyceride can significantly improve weight gain rate and feed efficiency of yellow catfish. Combined with the comprehensive evaluation of growth performance, serum immunity and antioxidant indexes, the optimal supplemental level of triglyceride in yellow catfish diet is 1 000 mg/kg. © 2023 Authors. All rights reserved.     

MC3R基因对京海黄鸡屠体性状的遗传效应分析

本研究以MC3R基因为鸡屠体性状的候选基因,旨在探讨其对京海黄鸡屠体性状的影响。运用PCR-SSCP方法结合测序技术,检测了MC3R基因在京海黄鸡群体中的多态性,并采用一般线性模型(GLM)分析基因型与屠体性状的遗传效应。结果显示,MC3R基因CDS序列检测区内,引物MR2、MR3和MR8扩增的片段具有多态性,其中引物MR2和MR3扩增片段均存在2个SNP位点,分别形成AA、AB、AC 3种基因型和EE、EF、FF、EH 4种基因型,引物MR8扩增片段只存在1个SNP位点,形成了KK、KL和LL 3种基因型;检测到的5个SNPs位点分别为CDS区C160A、G192T、C273T、G310A、G762A突变。关联分析结果显示,MR2位点对京海黄鸡各屠体性状(除腹脂质量)均有极显著影响(P0.01);MR3位点各基因型(排除个体数少于3的基因型)屠体性状间差异均不显著(P0.05),推断MR3位点对京海黄鸡屠体性状影响不显著(P0.05);MR8位点对京海黄鸡屠体质量、胸肌质量、腿肌质量、全净膛质量、半净膛质量有极显著影响(P0.01),对活体质量和腹脂质量有显著影响(P0.05)。对MR2和MR8 2个位点的效应进行联合分析,结果显示,2个位点组合基因型对所有屠体性状均有显著或极显著影响(P0.05或P0.01),其中AB/KK基因型组合为有利基因型组合,AA/LL基因型组合为不利基因型组合。因此,本研究可为京海黄鸡分子标记辅助育种提供依据,有利于加快对京海黄鸡屠体性状选择的育种进程,同时通过本研究可推测MC3R基因对家禽的屠体性状具有很大的遗传效应,为家禽育种工作提供理论依据。     

用黄酒滤渣生产苏云金杆菌的研究*

研究表明，利用生产黄酒的滤渣代替苏云金杆菌制剂生产中的部份原料，如酵母粉、淀粉等，取得了较好效果，用黄酒滤渣配方生产的苏云金杆菌，杀虫活性不低于原生产配方，并且生产成本降低30％以上。     

LED黄光诱虫灯对温室白粉虱的诱虫效果

运用固体冷光源发光二极管(LED)研制成的黄光诱虫灯对温室白粉虱进行诱杀试验,与生产常用的黄板做对比.结果表明:与黄板相比,LED黄光诱虫灯诱杀白粉虱的效果较好.     

北京怀柔区板栗黄化皱缩病害调查

在怀柔板栗主要产区对中国板栗黄化皱缩病进行了2 a的系统调查,结果为发病村占94.7%2,009年和2010年发病地块依次为34.6%和35.7%,发病株分别为3.58%和3.77%,平均病情指数分别为0.0147和0.0149。病害分为发病初期、发病盛期、滞留期、稳定期和落叶期5个阶段,用PCR扩增16S rRNA基因检测植原体,检出率81.2%;在感病板栗林内采集到蝽类、叶蝉和栗斑蚜共11种刺吸式昆虫。