First report of the South American tomato leafminer, Tuta absoluta (Meyrick), in China

et al. 2021

Insects

The tomato leaf miner, Tuta absoluta is a destructive pest of tomato. The leaf-mining activities of its larvae can cause significant yield losses. Real-time quantitative polymerase chain reaction (RT-qPCR) is commonly used to measure gene expression, and the selection of stable reference genes for calibration and standardization is critical for accurate use of RT-qPCR. We studied the stable expression of nine common housekeeping genes in T. absoluta. These were examined at different developmental stages, in larval tissues, as well as those induced by exposure to 20E and insecticides. Four dedicated algorithms (geNorm, BestKeeper, NormFinder, and ΔCt method) and online tool (RefFinder) were used to analyze and rank the tested reference genes. Based on the standardized gene expression data of target gene ecdysone receptor (EcR), the applicability of specific reference genes was verified. The results clarify that the optimal internal reference genes vary greatly under different experimental conditions. GAPDH and RPS11 were the best reference genes for developmental stages; RPL28 and RPL10 for different tissues; EF1α and RPL28 for 20E treatment; EF1α and RPL7A for insecticide treatments. The most suitable reference genes in all experimental conditions are EF1α and RPL28.

Section: Introductionmentioning

confidence: 99%

Selection and Validation of Reference Genes for Gene Expression Analysis in Tuta absoluta Meyrick (Lepidoptera: Gelechiidae)

Yan

et al. 2021

Insects

“…7,10,12 By the end of 2019, T. absoluta had spread through 88 confirmed and 23 unconfirmed (numbers indicated in parentheses) countries and districts worldwide: 29 European, 24 (14) African, 2 Central American, 22 (6) Asian, 1 North America, and 10 (3) South American. 8,[12][13][14][15][16][17] China is one of the major tomato-producing regions of the world. 18 Across China, the largest total cropping area and highest output of tomatoes are found in Xinjiang (a province-level autonomous region consisting of 14 prefectures) and the largest total cropping area and output of fresh-market and cherry tomatoes are found in Yunnan.…”

Section: Introductionmentioning

confidence: 99%

“…18 Across China, the largest total cropping area and highest output of tomatoes are found in Xinjiang (a province-level autonomous region consisting of 14 prefectures) and the largest total cropping area and output of fresh-market and cherry tomatoes are found in Yunnan. 19,20 The notorious T. absoluta pest was detected in northwestern China in Ili, Xinjiang in 2017 and southwestern China in Lincang, Yunnan in 2018, 17,20 having caused serious damage to tomato crops in Ili. 17 T. absoluta rapidly spread via tomato fruit and seedling commercialization and importation from infested areas.…”

Section: Introductionmentioning

confidence: 99%

“…19,20 The notorious T. absoluta pest was detected in northwestern China in Ili, Xinjiang in 2017 and southwestern China in Lincang, Yunnan in 2018, 17,20 having caused serious damage to tomato crops in Ili. 17 T. absoluta rapidly spread via tomato fruit and seedling commercialization and importation from infested areas. 12,21,22 They can also feed and survive on species from eight other plant families apart from Solanaceae.…”

Section: Introductionmentioning

confidence: 99%

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Outbreak of the South American tomato leafminer, Tuta absoluta, in the Chinese mainland: geographic and potential host range expansion

Xian

Pest Management Science

et al. 2021

Self Cite

BACKGROUND: In 2017 Tuta absoluta was identified as an invasive species in China. Due to its rapid geographic expansion and the severe crop damage it causes, T. absoluta poses a serious threat to China's tomato production industry. To determine its geographic distribution and host range, intensive surveys and routine monitoring were conducted across the Chinese mainland between 2018 and 2019. The population colonization coefficient (PCC; ratio of colonized sites and prefectures) and population occurrence index (POI; ratio of infested host species and PCCs) were calculated.RESULTS: In northwestern China, T. absoluta populations established in Xinjiang exhibited a medium PCC value (∼0.03). In southwestern China, populations in Yunnan and its five neighboring provinces exhibited high (∼0.50 in Yunnan and Guizhou), or low (<0.02 in Guangxi, Sichuan, Hunan, and Chongqing) PCC values. In the Chinese mainland, infestations of four crop plant species (tomato, eggplant, potato, and Chinese lantern) and two wild plant species (black nightshade and Dutch eggplant) were identified; tomatoes were infested in every colonized province. Chinese lantern and Dutch eggplant are potentially novel hosts. Yunnan, Guizhou, and Xinjiang experienced the most serious damage (POI). In southwestern China, observed damage significantly decreased with increased distance from the first discovery site of T. absoluta to the farthest county of an infested province increased. CONCLUSION: T. absoluta populations are well-established and could potentially spread to other regions of China. The present study helps to inform the establishment of better pest management guidelines and strategies in China and tomato-producing regions worldwide.

“…The South American tomato leafminer, also known as T.absoluta (Meyrick) (Lepidoptera: Gelechiidae), is one of the most important invasive insect pests globally and has spread to more than 80 countries and regions [33,34]. It has recently invaded China [35] and spread rapidly, becoming well-established in Xinjiang and Yunnan [36] and threatening the growth and development of local tomato plants [33,37,38]. Previous studies assessing T. absoluta have primarily focused on biological characteristics, insecticide resistance, invasiveness and spread pathway, and integrative pest management [33,39]; however, few have assessed the molecular mechanism behind the environmental adaptability of T. absoluta.…”

Section: Introductionmentioning

confidence: 99%

Screening Potential Reference Genes in Tuta absoluta with Real-Time Quantitative PCR Analysis under Different Experimental Conditions

Yang

Wang

Huang

et al. 2021

Genes

Self Cite

Tuta absoluta is one of the most significant invasive pests affecting tomato plants worldwide. RT-qPCR has emerged as one of the most sensitive and accurate methods for detecting gene expression data. The screening of stable internal reference genes is the most critical step for studying the molecular mechanisms of environmental adaptability. The stable reference genes expressed in T. absoluta under specific experimental conditions have not yet been clarified. In this study, seven candidate reference genes (RPL27, RPS13, RPS15, EF1-α, TUB, TBP, and β-actin) and their optimal numbers were evaluated under biotic (developmental stages and adult tissues) and abiotic (insecticide, temperature, and plant VOC) conditions using four software programs. Our results identified the following reference genes and numbers as optimal: three genes (EF1-α, RPS13, and RPL27) for different developmental stages (egg, larva, pupa, unmated adult), two genes (RPS13 and TBP) for adult tissues (antenna, head, thorax, abdomen, leg), two genes (TBP and RPS13) for insecticides (Bacillus thuringiensis, chlorpyrifos, abamectin-aminomethyl, and chlorantraniliprole), two genes (RPL27 and TUB) for temperature-induced stresses (0, 25, and 40 °C), and two genes (RPS13 and TUB) for VOC-induced stresses (nonanal, α-phellandrene, and tomato leaves). Our results provide a reference for selecting appropriate reference genes for further study of the functional genes of T. absoluta under different experimental conditions.