Carrillo Daniel, Cruz Luisa F, Revynthi Alexandra M, Duncan Rita E, Bauchan Gary R, Ochoa Ronald, Kendra Paul E, Bolton Samuel J
Tropical Research and Education Center, University of Florida, Homestead, FL 33031, USA.
Electron and Confocal Microscopy Unit, United States Department of Agriculture, Agricultural Research Service, Beltsville, MD 20705, USA.
Insects. 2020 Apr 9;11(4):235. doi: 10.3390/insects11040235.
The lychee erinose mite (LEM), (Keifer) is a serious pest of lychee ( Sonn.). LEM causes a type of gall called 'erineum' (abnormal felty growth of trichomes from the epidermis), where it feeds, reproduces and protects itself from biotic and abiotic adversities. In February of 2018, LEM was found in a commercial lychee orchard on Pine Island, Florida. Infestations were recorded on young leaves, stems, and inflorescences of approximately 30 young trees (1.5-3.0 yrs.) of three lychee varieties presenting abundant new growth. Although LEM is present in Hawaii, this mite is a prioritized quarantine pest in the continental USA and its territories. Florida LEM specimens showed small morphological differences from the original taxonomic descriptions of Keifer (1943) and Huang (2008). The observed differences are probably an artifact of the drawings in the original descriptions. Molecular comparisons were conducted on the DNA of LEM specimens from India, Hawaii, Brazil, Taiwan, Australia and Florida. The amplified COI fragment showed very low nucleotide variation among the locations and thus, could be used for accurate LEM identification. The ITS1 sequences and partial 5.8S fragments displayed no nucleotide differences for specimens from any of the locations except Australia. Consistent differences were observed in the ITS2 and 28S fragments. The ITS1-ITS2 concatenated phylogeny yielded two lineages, with Australia in one group and Hawaii, India, Brazil, Florida and Taiwan in another. Specimens from Taiwan and Florida present identical ITS and rDNA segments, suggesting a common origin; however, analysis of additional sequences is needed to confirm the origin of the Florida population.
荔枝瘿螨（LEM），（凯弗）是荔枝（桑）的一种严重害虫。荔枝瘿螨会引发一种名为“瘿瘤”的虫瘿（表皮毛状体异常毡状生长），它在其中取食、繁殖并保护自己免受生物和非生物逆境的影响。2018年2月，在佛罗里达州派恩岛的一个商业荔枝果园中发现了荔枝瘿螨。在三个呈现大量新梢生长的荔枝品种的约30棵幼树（1.5 - 3.0年树龄）的幼叶、茎和花序上记录到了虫害。尽管夏威夷存在荔枝瘿螨，但这种螨在美国大陆及其属地是优先检疫害虫。佛罗里达州的荔枝瘿螨标本与凯弗（1943年）和黄（2008年）最初的分类描述相比，形态上存在细微差异。观察到的差异可能是原始描述中绘图的人为因素造成的。对来自印度、夏威夷、巴西、台湾、澳大利亚和佛罗里达州的荔枝瘿螨标本的DNA进行了分子比较。扩增的细胞色素氧化酶亚基I（COI）片段在不同地点之间显示出非常低的核苷酸变异，因此可用于准确鉴定荔枝瘿螨。除澳大利亚外，来自任何地点的标本的内转录间隔区1（ITS1）序列和部分5.8S片段均未显示核苷酸差异。在内转录间隔区2（ITS2）和28S片段中观察到了一致的差异。ITS1 - ITS2串联系统发育产生了两个谱系，澳大利亚在一组，夏威夷、印度、巴西、佛罗里达州和台湾在另一组。来自台湾和佛罗里达州的标本呈现相同的ITS和核糖体DNA（rDNA）片段，表明有共同的起源；然而，需要分析更多序列来确认佛罗里达州种群的起源。
