The pheromone frontalin and its dual function in the invasive bark beetle Dendroctonus valens.

The red turpentine beetle, Dendroctonus valens LeConte, is one of the most destructive invasive forest pests in China, having killed more than 6 million pines since its first outbreak in 1999. Little is known about D. valens pheromone biology and no aggregation pheromone has yet been identified.

[Community structure and its dynamics of predatory arthropod in jujube orchards intercropped with different herbage species].

By using community structural characteristic indices and principal component analysis, this paper studied the community structure and its dynamics of predatory arthropod in the jujube orchards intercropped with Astrugalus complanatus, Trifolium repen, Lotus comiculotus, and Medicago sativa. The results showed that in all test jujube orchards, spider and predatory insects were the predominant components of the predatory arthropod community, and their relative abundances were 48.3% - 52.

[Population structure and niche of main scale insects in jujube orchards intercropped with wheat].

To effectively control the scale insects in jujube orchards, a field study was made on the population structure and niche of Pseudococcus comstock Kuwane, Ceroplastes japonicus Green and Quadraspidiotus perniciosus Comstock in the jujube orchards intercropped with wheat in Taigu area of Shanxi Province. The results showed that at the early development stage of jujube trees, these three kinds of scale insects mainly distributed on the southeast direction of the lower and central parts of the tree crown, and P. comstock was the dominant species, with a wider breadth of two-dimensional temporal-spatial niche than the other two scale insects.

[Functional groups of natural enemies and their temporal-spatial dynamics in jujube orchard intercropped with herbage].

In this paper, an investigation was made on the temporal-spatial dynamics of the functional groups of natural enemies in the jujube orchard 2.5 km west of Taigu (112 degrees 8'E, 38 degrees 9'N, 780 m elevation), Shanxi Province in 2002, aimed to work out an effective strategy to control the pests there. In this orchard, four management modes were applied, i.