solutions for pest control [5]. Several insect orders including Coleoptera [6], Hemiptera [7], Hymenoptera [8] and Diptera [9, 10] have been reported to harbor persistent communities of microorganisms. However, the gut microbiome of Lepidoptera is sparsely described [11]. Out of the 157,424 recognized Lepidoptera species [12], <0.1% have been screened for bacterial symbionts, revealing the limited available knowledge on bacterial associates in Lepidoptera [13]. The lepidopteran microbiome is driven by many factors ranging from the environment, diet, gut physiology, and developmental stage [13]. Studies on insect gut bacteria have utilized both cultivable and culture-independent approaches [14]. Cultivable microbes are ideal for studying symbiotic interactions sustained within the host and are also ready to be genetically manipulated for other novel applications [15]. Conventional cultivation techniques are, however, unable to characterize most microbes with 80-90% of microbial species not yet cultured. Cultureindependent approaches such as using 16S metagenomics analysis provide a relatively unbiased view of the The polyphagous eri silk moth, Samia ricini, is associated with various symbiotic gut bacteria believed to provide several benefits to the host. The larvae of S. ricini were subjected to isolation of gut bacteria using culture-dependent 16S rRNA generic characterization, metagenomics analysis and qualitative enzymatic assays. Sixty culturable aerobic gut bacterial isolates comprising Firmicutes (54%) and Proteobacteria (46%); and twelve culturable facultative anaerobic bacteria comprising Proteobacteria (92%) and Firmicutes (8%) were identified inhabiting the gut of S. ricini. The results of metagenomics analysis revealed the presence of a diverse community of both culturable and un-culturable gut bacteria belonging to Proteobacteria (60%) and Firmicutes (20%) associated with seven orders. An analysis of the results of culturable isolation indicates that these bacterial isolates inhabited all the three compartments of the gut. Investigation on persistence of bacteria coupled with metagenomics analysis of the fifth instar suggested that bacteria persist in the gut across the different instar stages. In addition, enzymatic assays indicated that 48 and 75% of culturable aerobic, and 75% of anaerobic gut bacterial isolates had cellulolytic, lipolytic and nitrate reductase activities, thus suggesting that they may be involved in food digestion and nutritional provision to the host. These bacterial isolates may be good sources for profiling novel genes and biomolecules for biotechnological application.

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The sugarbeet root maggot, Tetanops myopaeformis Röder (Diptera: Ulidiidae), is native to North America. However, its primary crop host, sugarbeet, Beta vulgaris L., was introduced to the continent from Europe in the late 19th century. This field and greenhouse research was conducted to compare the relative attractiveness of eight cultivated and wild plant species for oviposition by T. myopaeformis, and the suitability of these potential host plants for larval development to elucidate the potential native and current host range of this pest. Results indicated that females preferred ovipositing in soil immediately adjacent to or on the following plant species: sugarbeet; spinach, Spinacia olerocea L.; common lambsquarters, Chenopodium album L.; redroot pigweed, Amaranthus retroflexus L.; Palmer amaranth, Amaranthus palmeri S. Wats.; and to a lesser extent, spear saltbush, Atriplex patula L. Larval survival was greatest on spinach, sugarbeet, and spear saltbush, which all belong to the family Chenopodiaceae. Larval survival on these plants suggests that T. myopaeformis could have exploited wild chenopodiaceous plants or others within the order Caryophyllales before sugarbeet was introduced to North America. Low larval survival on common lambsquarters, redroot pigweed, and Palmer amaranth suggests that these species are suboptimal hosts, despite demonstrated attractiveness for oviposition. A general lack of oviposition preference by T. myopaeformis females was observed for sunflower, Helianthus annuus L., and common ragweed, Ambrosia artemisiifolia L. These results provide insights regarding the successful and somewhat rapid host preference shift by this insect to sugarbeet after cultivation of the crop began in the continent.

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Oviposition preference and larval survival of the sugarbeet root maggot (SBRM), Tetanops myopaeformis (Röder), was evaluated on three cultivated plant species and five native North American weed species during the 2010 and 2011growing seasons near St. Thomas, in northeastern North Dakota. Treatments included the following: sugarbeet, Beta vulgaris L.; spinach, Spinacia oleroceae L.; sunflower, Helianthus annuus L.; common lambsquarters, Chenopodium album L.; redroot pigweed, Amaranthus retroflexus L.; Palmer amaranth, A. palmeri S. Watts.; spear saltbush, Atriplex patula L.; and common ragweed, Ambrosia artemisiifolia L. The most preferred plant species for egg deposition by SBRM flies included Palmer amaranth, sugarbeet, spinach, common lambsquarters, spear saltbush, and redroot pigweed. Recovery of live third-instar larvae was highest on spinach, sugarbeet, and spear saltbush. Spear saltbush is considered to be native to central and northern latitudes of the continent, further indicating that this species could have served as a common or preferred SBRM host before the apparent host preference shift to sugarbeet. Lower levels of survival were observed on common lambsquarters, redroot pigweed, and Palmer amaranth. These findings suggest that the SBRM could have used some of these weed species as hosts because sugarbeet and spinach are not native to North America. Our observed SBRM survival on weed species in this study suggests that the pest made a significant preference shift to sugarbeet monocultures. Oviposition and larval survival on other plant species suggests that these plants can still serve as alternate hosts. These findings may have important SBRM management implications, especially if one of these weeds becomes resistant to herbicides commonly used sugarbeet.