To determine the distribution characteristics of heavy metal pollution in farmland soils and related influencing factors in the Taige canal valley, and guarantee soil environmental quality and safety of agricultural products, 118 topsoil samples were collected from the Taige canal valley's farmland soils, and contents of chromium (Cr), mercury (Hg), arsenic (As), copper (Cu), zinc (Zn), nickel (Ni), lead (Pb), and cadmium (Cd) were measured. A single factor index and comprehensive index were used to assess soil heavy metal contamination with the soil background value of the Taihu Lake basin as the evaluation standard. The multivariate statistical analysis and the geostatistical analysis were combined to identify and apportion the pollution sources of soil heavy metals.
View Article and Find Full Text PDFTo compare the performance of Frankliniella occidentalis (Pergande) and native Frankliniella intonsa (Trybom) on cucumber and tomato leaves in laboratory, life history characters were investigated, and life tables were constructed using the method of age-stage, two-sex table life. Compared with tomato leaf, there were shorter total preoviposition period (TPOP), higher fecundity, longer female longevity, and higher intrinsic rate of increase (r) of both F. occidentalis and F.
View Article and Find Full Text PDFPhloem-feeding whiteflies in the species complex Bemisia tabaci cause extensive crop damage worldwide. One of the reasons for their "success" is their ability to suppress the effectual jasmonic acid (JA) defenses of the host plant. However, little is understood about the mechanisms underlying whitefly suppression of JA-regulated defenses.
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