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Reductholaspis Emberson is rediagnosed with the description of a new species, Reductholaspis longicorniculussp. nov. Shen & Yi from southwestern China. This is the first report of the genus Reductholaspis from the Oriental Region and the first described male for the genus. Reductholaspis longicorniculussp. nov. is distinguished from R. analis Hyatt & Emberson by the dorsal shield with 28 pairs of setae, posterior margin of the sternal shield with deep hollows lateral to iv2, latigynal sclerites well developed, metasternal plates ovate, all setae on coxae I–IV pilose, tarsus I with proximal pilose setae, and three pairs of lightly sclerotized platelets between the epigynal shield and anal shield. [ABSTRACT FROM AUTHOR]

Five species of Unionicola Haldeman, 1842 (Acari: Hydrachnidia: Unionicolidae) were collected between 2018 and 2019. Notably, Unionicola (Armatax) armata Walter, 1929, previously unrecorded in China, is now documented for the first time in the country. Additionally, Unionicola newsumi Wiles, 1999 has been reclassified and assigned to the new subgenus Vespicola within the genus Unionicola Haldeman, 1842. These findings also led to the establishment of three new subgenera: Micronodusgen. nov., Vespicolagen. nov., and Lingshuiataxgen. nov. including four species: Unionicola soluplatussp. nov. U. jinisp. nov. U. caudipessp. nov. and U. armatallasp. nov. This marks the first description and documentation of these subgenera and species. [ABSTRACT FROM AUTHOR]

Flaveria bidentis (L.) Kuntze, an invasive plant, poses a serious threat to the structure and function of the native ecosystem in Hebei Provience, China. However, little is known about the allelopathic activity of the residues of this plant species. In this study, the impact of the phytotoxicity of unburnt (UR) and burnt (BR) residues of the exotic invasive weed on the growth of wheat (Triticum aestivvm L.) was assessed. Extracts prepared from both UR and BR reduced the shoot length, root length and dry weight of wheat significantly compared with the control, thereby indicating the presence of some water-soluble allelochemicals in F. bidentis residues. Growth studies conducted in soil amended with UR and BR extracts or residues also revealed phytotoxic effects towards wheat. A significant amount of phenolics was detected in the residue extracts and in residue-incorporated soil. The phenolic content rose with increasing residue concentration, thereby showing their direct involvement in the observed growth inhibition. The inhibition of wheat growth by the burnt residue and its water extracts was similar to that of unburnt residue, so burning it is not a good way to eliminate the allelopathic effects of the residue of F. bidentis on native plants. [ABSTRACT FROM PUBLISHER]

Since insects are ectothermic, they are highly vulnerable to the sudden increase of temperature. Indeed, it has been hypothesized that the survival, development, fecundity, and even population expansion of insects are all affected significantly by extremely high temperature. We studied the effect of short-term high temperature stress on the survival and development of different stages, adult longevity and fecundity of Ophraella communa (Coleoptera: Chrysomelidae), a biological control agent of the invasive plant, the common ragweed, Ambrosia artemisiifolia (Asterales: Asteraceae) in the laboratory. The results showed that egg, larval, pupal and adult survival rates were significantly affected after 2 hour-short-stress at high temperatures (35 to 47°C) when compared to the 28°C control. With the exceptions of the control and 35°C stress, survival rate of females was significantly higher than that of males after short-stress at any high temperature. Short-term high temperature stress also significantly impacted longevity and fecundity of adult beetles. Except for control, female longevity was significantly longer than male's after short-stress at any high temperature. The survival rates of different stages, and adult longevity and fecundity of the beetle decreased significantly with the increase of short-term stress temperature. Based on the results of the present study, we conclude that the development and population expansion of O. communa may be significantly affected when they are exposed to a high temperature stage in a summer day in the areas invaded by common ragweed, in southern China. [ABSTRACT FROM AUTHOR]

Dambullaeus hainanensis Xu & Jin sp. nov. is described and illustrated based on larvae ectoparasitic on Delphacidae (Hemiptera) from Hainan Island, China. A modified generic diagnosis of larval Dambullaeus is provided and a key to the species of larval Dambullaeus is presented. [ABSTRACT FROM AUTHOR]

The genus Dyneogamasus is transferred to the subfamily Pergamasinae, and the generic diagnosis is revised. A new mite species, Dyneogamasus serratus Yao & Jin sp. nov., is described and illustrated based on females from Fujian province, China. A key to the known species of the genus is given. [ABSTRACT FROM AUTHOR]

Two new water mites species of the genus Sperchon Kramer, 1877 from China, Sperchon synsetus sp. nov. and Sperchon xiaoqikongensis sp. nov. are described and illustrated in this article. Sperchon synsetus sp. nov. differs from known species of the genus in the following: cuticle covered with very fine spinules arranged in polygonal pattern and each polygon with an annular line inside; two peg-like setae fused at the base on the ventral side of P-IV. Sperchon xiaoqikongensis sp. nov. is characterized by cuticle covered with scale-shaped papillae; P-II with an obtuse projection bearing three setae and A1 setae is plumose. To the present, 18 species of the genus Sperchon have been described from China. [ABSTRACT FROM AUTHOR]

Understanding distribution and diversity of invasive weeds is essential for the development of efficient control measures against it. In the present study, inter-simple sequence repeat (ISSR) markers were used to assess the biogeographic relationships among populations of the invasive Crofton weed (Ageratina adenophora (Spreng.)) during 2004-2006 in China. A total of 100 ISSR primers with di-, tri-, tetra- and penta-nucleotide repeats were screened, from which 20 polymorphic and informative primers were selected. Amplification of the 20 primers generated a total of 479 polymorphic bands among the 64 weed populations, and a high level of genetic diversity (HE = 0.1541 ± 0.0193) was detected in A. adenophora. Neighbor-joining (NJ) cluster analysis based on genetic distances among populations grouped the populations according to their geographical origin, i.e. (1) populations of southwestern Guizhou, (2) populations of Liangshan city in Sichuan, (3) populations of western Guizhou, (4) Guangxi populations plus Chongqing populations, (5) populations of southern Yunnan, and (6) populations of Yangtze River Valleys in Sichuan plus populations of western Yunnan. A significant positive correlation between geographical and genetic distance was detected by the Mantel test (r = 0.183, p = 0.0012). Based on the divergence relationships revealed by ISSR markers, it was assumed that A. adenophora mainly dispersed through wind and water in China. [ABSTRACT FROM AUTHOR]

Alloeuzercon seemani Sun, Jin & Yi gen. & sp. nov. (Acari: Mesostigmata: Celaenopsoidea: Euzerconidae) associated with passalid beetles (Coleoptera: Passalidae) is described, representing the first record of the family Euzerconidae from China. The new genus bears a close resemblance to the genera Euzerconoides and Paraeuzercon, prompting us to update the key to genera. [ABSTRACT FROM AUTHOR]

The genus Arrhenoseius Walter & Lindquist, 2000 is recorded for the first time from the Oriental Realm on the basis of two new species. Arrhenoseius hallidayisp. nov. can be distinguished from other species of the genus by the ventrianal shield bearing five pairs of ventral setae and unsclerotised ventro-lateral cuticle without setae in the adult female, and Arrhenoseius granulatussp. nov. can be distinguished by the ventrianal shield bearing eight pairs of ventral setae and unsclerotised lateral cuticle with six pairs of setae. A key to species of Arrhenoseius is given based on the adult females. [ABSTRACT FROM AUTHOR]

The mixture ofBacillus subtilisstrain SM21 andBacillus cereusstrain AR156, referred to as ASB, is a biopesticide in the process of registration in China, which has the capacity of controlling root-knot nematode in cucumber,Phytophthorawilt in pepper andRalstoniawilt in tomato. In this study, we tested its effects on a range of physiological indicators of plant growth including biomass, yield, chlorophyll content and fruit nutrients of pepper, as well as, its efficacy in controlling bacterial wilt caused byRalstonia solanacearumunder field conditions in 2009 and 2010 by a variety of inoculation methods. Three application methods – soaking seeds, drenching soil around seeds right after sowing and drenching the rhizosphere of transplanted seedling with the aqueous solution (as a soil drench) –and three concentrations of ASB (1.0 × 106CFU/mL, 1.0 × 107CFU/mL, and 1.0 × 108CFU/mL) were employed. The results showed that both soaking seeds with ASB at 1.0 × 107CFU/mL as well as drenching rhizosphere with ASB at 1.0 × 106CFU/mL and 1.0 × 107CFU/mL promoted growth, increased yield and fruit nutrient contents of pepper. The combination of these two inoculation methods led to significant increases in growth and fruit nutrient contents. We found that the most effective way was the combination of soaking seeds with the ASB at 1.0 × 107CFU/mL and drenching rhizosphere with it at 1.0 × 106CFU/mL, which is also easy for Chinese farmers to implement. [ABSTRACT FROM PUBLISHER]

Ambrosia artemisiifoliaL. is native to North America, and was unintentionally introduced into China in the 1930s, where it has become invasive. The two insect speciesEpiblema strenuanaandOphraella communahave been considered as biological control agents ofA. artemisiifoliain China. The purpose of this study was to examine the control effect ofO. communa+E. strenuanaonA. artemisiifoliain the field. The mortality ofA. artemisiifoliaplants increased with time and increasing initial release densities ofO. communaand/orE. strenuanain 2008 and 2009. The treatments of 0.53O. communa+ 0.53E. strenuanaper plant and 12O. communa+ 16E. strenuanaper plant at early (60–70 cm tall) and later (90–100 cm tall) growth stages could subsequently kill all plants prior to seed production in both 2008 and 2009. Thus, the two initial densities of the two insect species may be recommended when they are jointly used for biological control ofA. artemisiifoliaat the two growth stages. However, all or some plants could survive and bear seeds in any other treatment and in the non-treated control plots. This implies that biological control ofA. artemisiifoliawith the two biological control agents will be recommended in the areas invaded byA. artemisiifoliain China. [ABSTRACT FROM AUTHOR]