基于Faster R-CNN的榆紫叶甲虫识别方法研究

针对传统图像识别方法中利用人工设计特征提取模板对昆虫的识别精度不高的问题,提出了基于K-means聚类的深度学习网络模型Faster R-CNN对图像中的目标进行识别。该方法用K-means聚类算法,结合BWP指标对训练数据标签的长宽比值进行聚类,用新的聚类中心点代替标准Faster R-CNN网络中生成初始候选框的长宽比值;对生成初始候选框的尺寸加以改进;将训练数据送入改进后的Faster R-CNN网络进行训练。实验结果表明,在识别具有特定长宽比例的目标时,加入聚类策略的Faster R-CNN网络较标准Faster R-CNN网络有较强的鲁棒性,有效克服了叶片豁口或孔洞造成的冗余现象、榆紫叶甲虫甲壳反光的干扰、相邻的榆紫叶甲虫特征的互相影响和其他与榆紫叶甲虫有相似特征的种类昆虫的干扰。最终达到94.73%的识别精度,较标准网络提高了4.15%。该方法可有效克服传统昆虫检测中特征提取模板的局限性,对识别昆虫这种特征细腻,姿态多样的目标有重要意义。

柑橘几种食叶甲虫的发生为害与综合治理

柑橘是闽西北地区的主要果树,柑橘食叶甲虫是为害柑橘梢、嫩叶、花的一类重要害虫.主要有柑橘恶性叶甲、橘潜叶甲、柑橘灰象甲.近年来此类害虫有加重为害的趋势,为害严重时,削弱树势,影响产量.近年通过对本地区此类害虫发生规律的观察,并制定实施防治技术,获得很好的防治效果.

甘草萤叶甲虫害田间防治药剂筛选与药效评价

本试验在田间条件下,研究了1%苦参碱水剂、20%呋虫胺悬浮剂、0.8%·160亿孢子/mL阿维·球孢白僵菌油悬浮剂、70%吡虫啉WG对甘草萤叶甲的药效和使用浓度及甘草的安全性,结果表明,1%苦参碱水剂2000、1500、1000倍液,20%呋虫胺悬浮剂2000、1500、1000倍液,0.8%·160亿孢子/mL阿维·球孢白僵菌油悬浮剂750、600、500倍液,70%吡虫啉WG 10000、7500、5000倍液,药后10 d对甘草萤叶甲虫害的防效都在97.44%以上,都表现出较好的持效性和较高的防效。尤其20%呋虫胺悬浮剂2000倍液和1500倍液、0.8%·160亿孢子/mL阿维·球孢白僵菌油悬浮剂500倍液、70%吡虫啉WG 10000倍液防效达到100.00%,生产中可在萤叶甲始盛期的5月下旬选择无风的早晨进行施药防治,上述4种药剂可交替使用。

桤木叶甲虫的发生及其防治

桤木叶甲,在我省大面积发生后,1991年全省受灾面积达296万亩。该虫为桤木叶片、嫩梢专食性害虫,属全变态,以成虫在林下枯枝落叶层、瓦檐下、石缝等处越冬。大发生时,每株树上聚集上万头,叶片吃成网状,桤木枯梢枯死,形如火烧。叶甲虫在四川一年发生5～7代,4月上旬上树活动取食,中下旬产卵,雌虫产卵量最高达620粒,平均产卵量360粒。卵期4～8天,

赤杨叶甲生物学特性的初步研究

赤杨叶甲Agelastica coerulea Baly是赤杨Alnus japonica(Thunb.)Steud.的重要食叶害虫。一年2代,以成虫在枯枝落叶层或杂草中越冬。越冬成虫于4月下旬开始活动取食,5月中旬产卵,6月中旬出现第1代成虫,8月中下旬出现第2代成虫,9月中下旬开始越冬。在越冬成虫产卵前喷洒80％敌敌畏乳油或敌杀死1000—2000倍液,防治成虫能较好地控制其危害。

科技动态

据美联社东京消息：日本一家公司发明了一个装置，可以将花朵变成扬声器发出悦耳的乐音，花瓣和叶子还会随着音律的振动起舞。这个被称为“花音”的装置是一个底部有一个环形磁石和电线圈的花瓶，花瓶与CD唱机、音响设备或电视机连接。把花插在瓶子里，开着开关掣，磁石和电线圈就会将音波的振动透过植物的水管传送到花茎。将耳朵凑近花朵，就会听到花瓣发出音乐声，抚摸叶子，会感觉到它在颤动，就像是在跳舞。“花音”把声音向各个方向辐射，令到整个房间充满更有自然氛围的音乐。价钱由3000-5000日元不等，由7月开始在互联网上接受订购。

Recent advances in the molecular genetics of resin biosynthesis and genetic engineering strategies to improve defenses in conifers

Since the first terpenoid synthase cDNA was obtained by the reverse genetic approach from grand fir, great progress in the molecular genetics of terpenoid formation has been made with angiosperms and genes encoding a monoterpene synthase, a sesquiterpene synthase, and a diterpene synthase. Tree killing bark beetles and their vectored fungal pathogens are the most destructive agents of conifer forests worldwide. Conifers defend against attack by the constitutive and inducible production of oleoresin that accumulates at the wound site to kill invaders and both flush and seal the injury. Although toxic to the bark beetle and fungal pathogen, oleoresin also plays a central role in the chemical ecology of these boring insects. Recent advances in the molecular genetics of terpenoid biosynthesis provide evidence for the evolutionary origins of oleoresin and permit consideration of genetic engineering strategies to improve conifer defenses as a component of modern forest biotechnology. This review described enzymes of resin biosynthesis, structural feathers of genes genomic intron and exon organization, pathway organization and evolution, resin production and accumulation, interactions between conifer and bark beetle, and engineering strategies to improve conifer defenses.

Regional Risks for Biogas Production in Germany by the Maize Pest Diabrotica v. virgifera？

Caused by its multi purpose applicability in different areas of the energy system, biogas is an important source for the concept of ＂Energy Turnaround for Sustainability＂. To clarify the regional risks for biogas production due to Diabrotica virgifera virgifera （Coleoptera： Chrysomelidae） （Dw） results from the questionnaire on the current situation of the biogas plants in Germany are compared to our Dvv monitoring experiences and literature data. Maize silage is the main source for biogas production in Germany. Dvv is the most important maize pest within the United States. It also was monitored in different German States during the last years. The Dvv infestation risk and consequent damages are closely linked to the percentage of maize within the regional crop rotations scheme. Maize cropping within a monocultural production can lead to a significant harvest reduction of 30% to 80% after the outbreak of Dvv, especially in dry years. A high risk to the biogas production based on silage maize especially in some areas in North West and in southern Germany has been detected. Further research is needed focusing on （1） strategies to control Dvv, （2） development in alternative energy crops regarding their susceptibility to Dvv and （3） development of technologies along the process chains for using alternative substrates, especially residues from plant production.

Vertical and seasonal distribution of flying beetles in a suburban temperate deciduous forest collected by water pan trap

Vertical and seasonal distributions of flying beetles were investigated in asuburban temperate deciduous forest in Kanazawa, Japan using water pan traps to determine the abundance and composition among vertical strata, change in the abundance and composition through seasons and determinant factors in generating the distributions. Traps were placed at three levels (0.5 m, 10 m, and 20 m above ground) on a tower. Samplings were carried out seasonally from May to November in 1999 and 2000. Variations in the abundance of flying beetles were observed from different layers. The results showed that the abundance and composition of flying beetles varied among strata and seasons. In both 1999 and 2000,Elateridae was consistently most abundant in the bottom layer, while Attelabidae and Cantharidae were most abundant in the upper layer. In 1999, Eucnemidae and overall scavengers were most abundance in the bottom layer, but results were not consistent with those in 2000. In general, the abundance of herbivores reaches a peak in the early season(May/June) and decreases in the following months. Peaks of abundance in predators vary vertically. In the bottom layer a peak was observed in the early season (May/June), while in the upper layer this was observed in July. Scavengers had two peaks, in May/June and September. These patterns indicated that vertical distributions in the abundance of differentfeeding guilds varied through seasons.