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To study the identification mechanism of microplastics in agricultural environmental media by molecular spectroscopy, two typical media, soil and fishmeal, were selected for this study. Three common microplastics, PE, PP, and PS, were used as research objects. Near-infrared (NIR) and mid-infrared (MIR) spectroscopy combined with chemometric methods were used to explore microplastics' identification and analysis effects in different agricultural media and reveal their identification mechanisms. PCA analysis revealed that different soil types would affect the identification results of microplastics. PLS-DA discriminant analysis showed that the accuracy of NIR spectroscopy technology in identifying microplastics in different types of soil decreased in the order of sand > loam > clay. In contrast, the rule of MIR spectroscopy technology was the opposite. The sensitivity and specificity of the three microplastics in the NIR model of sand and the infrared spectroscopy model of fishmeal reached 1.000. NIR spectroscopy technology is suitable for identifying microplastics in soil, while infrared spectroscopy technology is more suitable for identifying microplastics in fish meal. Furthermore, based on the VIP values of each wavelength point in the spectrum, the characteristic bands that have essential contributions to identifying microplastics in soil were screened out. The NIR spectra of 4500–4300 cm − 1 , 4300–3900 cm − 1 and 7100–5800 cm − 1 are the most essential characteristic bands for identifying microplastics in clay, loam, and sand, respectively. The MIR of 3000–2900 cm − 1 and 700–650 cm − 1 were the most essential characteristic bands for identifying microplastics in soils, and the overlap of the characteristic spectra of the three soils reached 59.45%. The NIR spectra of 6050–5600 cm − 1 , 4700–4000 cm − 1 and the MIR spectra of 2300–1900 cm − 1 and 800–400 cm − 1 are the most essential characteristic bands for the identifying microplastics in fishmeal. This study provides a more suitable technical "solution" for identifying microplastics in environmental media, which is of great significance for improving the accuracy of molecular spectroscopic identification in environmental media and clarifying the interaction between microplastics and environmental media. [ABSTRACT FROM AUTHOR]

Summary: Fruit neck length (FNL) is an important quality trait in cucumber because it directly affects its market value. However, its genetic basis remains largely unknown. We identified a candidate gene for FNL in cucumber using a next‐generation sequencing‐based bulked segregant analysis in F2 populations, derived from a cross between Jin5‐508 (long necked) and YN (short necked). A quantitative trait locus (QTL) on chromosome 7, Fnl7.1, was identified through a genome‐wide comparison of single nucleotide polymorphisms between long and short FNL F2 pools, and it was confirmed by traditional QTL mapping in multiple environments. Fine genetic mapping, sequences alignment and gene expression analysis revealed that CsFnl7.1 was the most likely candidate Fnl7.1 locus, which encodes a late embryogenesis abundant protein. The increased expression of CsFnl7.1 in long‐necked Jin5‐508 may be attributed to mutations in the promoter region upstream of the gene body. The function of CsFnl7.1 in FNL control was confirmed by its overexpression in transgenic cucumbers. CsFnl7.1 regulates fruit neck development by modulating cell expansion. Probably, this is achieved through the direct protein–protein interactions between CsFnl7.1 and a dynamin‐related protein CsDRP6 and a germin‐like protein CsGLP1. Geographical distribution differences of the FNL phenotype were found among the different cucumber types. The East Asian and Eurasian cucumber accessions were highly enriched with the long‐necked and short‐necked phenotypes, respectively. A further phylogenetic analysis revealed that the Fnl7.1 locus might have originated from India. Thus, these data support that the CsFnl7.1 has an important role in increasing cucumber FNL. [ABSTRACT FROM AUTHOR]