Pinewood nematode (Bursaphelenchus xylophilus) is a highly destructive invasive species, causing extensive economic and ecological losses across Eurasia. It has recently invaded mid-temperate zone of northern China, threating large areas of coniferous forests. Herein, we evaluated the physiological and molecular basis of cold tolerance in pinewood nematode isolates from different temperature zones of China. After exposure to −5 °C and −10 °C, the survival rates of five pinewood nematode isolates from different temperature zones were 93.94%–94.77% and 43.26%–45.58% after 8 h, and 93.04%–94.85% and 9.93%–10.56% after 24 h, without significant differences among isolates. In a comparison of an isolate from a mid-temperate zone and an isolate from a subtropical zone under gradient cooling, the survival rates remained steady at nearly 95% when minimum temperature ranged from −5 °C to −15 °C, with no significant difference between isolates. In addition, phylogenetic and population structure analyses based on whole genome resequencing data suggested that isolates from mid-temperate and warm temperate zones are clustered with different isolates from subtropical zone, with no obvious geographic pattern. We did not detect significant variation in cold tolerance ability and selected gene among pinewood nematode isolates from different temperature zones. The recently invaded pinewood nematodes in the mid-temperate zone of northern China may spread by multiple invasion events from southern China, without adaptive revolution. Our research implies that it is important to reinforce quarantine inspection to control the rapid spread of pinewood nematode.

The angle of repose in soil particles plays a key role in slope stability. There was a need for the investigation on the association between the angle of repose in loess particles and the angle of slopes. The fixed funnel methods with different particle sizes were carried out. The pressure of particle gravity weight was obtained based on the vibration stacking test. Four contact structures in loess particles were put forward including the triangular pyramid contact structure (TS), rectangular pyramid contact structure (RS), pentagonal pyramid contact structure (PS), and hexagon contact structure (HS). The particles transformed successively in four kinds of contact structures. The transformation of entropy value of the particles in different accumulation areas was discussed during the process of accumulation. The relationship between the natural angle of repose and the evolution of the contact structures was established. Combined with the existing experimental conclusion that loess particles transform in four stable states, in turn, the reason that the friction angle of uniform sand particles proposed by Shields in 1936 is 33° was explained. The formation theory of the loess angle of repose was well extended to speculate the formation process of the loess slope system. It is verified that loess slopes were mainly distributed under 30°.

Eogystia hippophaecolus Hua, Chou, Fang et Chen (Lepidoptera: Cossidae) is a notorious carpenterworm pest of sea buckthorn, Hippophae rhamnoides L. (Elaeagnaceae). Chemosensory proteins (CSPs) are thought to be responsible for initial biochemical recognition during olfactory perception by the insect. We examined the structure, function, and expression profiles of these proteins in four structures (e.g., antennae, labipalp, legs, and external genitalia) of male adults. Molecular weight, isoelectric point, hydrophilicity and hydrophobicity of proteins, and signal peptide prediction of 18 E. hippophaecolus CSPs (EhipCSPs) were investigated via software. Expression profiles in the four male structures were analyzed by fluorescence quantitative real-time polymerase chain reaction. Bioinformatics analysis showed that most EhipCSPs are low-molecular-weight proteins with hydrophobic regions and a high proportion of alpha-helices, consistent with the general characteristics of insect CSPs. Eight EhipCSPs (EhipCSP2, EhipCSP5, EhipCSP7, and EhipCSP13–17) were predominantly expressed in the labipalp (P < 0.01), and three (EhipCSP6, EhipCSP8, and EhipCSP9) were predominantly expressed in legs (P < 0.01). We speculate that these proteins may be related to contact sensations, host recognition, and other functions. Two EhipCSPs (EhipCSP4 and EhipCSP11) were highly expressed in the external genitalia (P < 0.01), suggesting that they may be involved in spousal positioning or mating activities. Most EhipCSPs were differentially expressed in the four structures, with wide overall expression, indicating an important role in olfactory recognition in multiple tissues. Our findings establish the foundation for further investigation of EhipCSPs and potential development of nonpesticide control measures.

A FMCW W-band radar system and assembly of chipset have been proposed. Low phase noise, enough transmit power and good receiver noise performance have been achieved from 81.24GHz to 85.92GHz. Range detection function has been verified through the IF output calculation. What's more, to improve the reliability of the chipset and radar system, a package for the transmitter chip has been design. Functions of the package has been verified and electromagnetic performance has been examined by simulation.

Microplitis manilae (Ashmead) (Hymenoptera: Braconidae) is a solitary endoparasitic wasp of Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), a significant agricultural pest. We compared the parasitism of M. manilae on the first-, second-, and third-instar larvae of S. frugiperda and found that M. manilae prefered the second instar. We investigated the effect of 5 temperatures (18, 22, 26, 30, and 34 °C) on the development period in the immature stage of M. manilae and found that moderately high temperatures shortened the development time. Considering the development period, cocooning rate, and emergence rate, 26 °C was the optimal temperature for the highest value of females’ fecundity. We also examined the development of the immature stage of M. manilae by dissecting parasitized hosts and cocoons in the laboratory. Our results revealed that the eggs matured within 2 d, and the larvae progressed through 3 instars, culminating in a total developmental period of about 9 d. The prepupal stage retained the larval form, and the pupa pigment gradually precipitated after molting. All stages were documented in detailed micrographs. Our study lays a robust foundation for further studies on the physiological interactions between M. manilae and S. frugiperda.