A communal catalogue reveals Earth’s multiscale microbial diversity

Our growing awareness of the microbial world’s importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth’s microbial diversity

A communal catalogue reveals Earth's multiscale microbial diversity

Our growing awareness of the microbial world's importance and diversity contrasts starkly with our limited understanding of its fundamental structure. Despite recent advances in DNA sequencing, a lack of standardized protocols and common analytical frameworks impedes comparisons among studies, hindering the development of global inferences about microbial life on Earth. Here we present a meta-analysis of microbial community samples collected by hundreds of researchers for the Earth Microbiome Project. Coordinated protocols and new analytical methods, particularly the use of exact sequences instead of clustered operational taxonomic units, enable bacterial and archaeal ribosomal RNA gene sequences to be followed across multiple studies and allow us to explore patterns of diversity at an unprecedented scale. The result is both a reference database giving global context to DNA sequence data and a framework for incorporating data from future studies, fostering increasingly complete characterization of Earth's microbial diversity.Peer reviewe

The Effects of Spodoptera Exigua Herbivory on Soybean Plant Chemistry

Many plants have induced responses to herbivory whereby the plants turn on defensive chemicals to deter herbivores. Both trypsin inhibitors and chitinase can be induced by herbivores. Trypsin inhibitors can stunt development and deter insect feeding. Chitinase exhibits hydrolytic activity towards the structural component of insects called chitin, and it can delay insect development. The purpose of this experiment was to examine the effect of caterpillar herbivory on defensive chemical induction in soybeans. For this experiment, 15 soybeans plants were exposed to beat armyworm, Spodoptera exigua, herbivory and 15 plants were used as the control group. Caterpillars were placed directly on the plant and left to feed for 72 hours. Then two leaves per plant were removed and chitinase and trypsin inhibitor concentrations were measured. It was hypothesized that there will be a significant difference in the production of trypsin and chitinase between the caterpillar treatment and the control group

Kudzu Bug Preference Across Four Soybean Varieties

The kudzu bug,Megacopta cribraria,was first discovered in Georgia in 2009. Soybeans are a profitable agricultural crop and a host plant for kudzu bugs. The purpose of this experiment was to determine if kudzu bugs would exhibit a preference between rhizobia-inoculated and un-inoculated treatments across four different soybean varieties (Butterbean, Viking, Black jet, and Tohya). Rhizobia bacteria allow nodulation and nitrogen fixation in soybeans. Kudzu bug preference was determined by placing 6-10 kudzu bugs into a bug dorm with one inoculated and one uninoculated plant. Soybean varieties were examined separately. For two days, the number of kudzu bugs present on each plant was counted and recorded twice a day. There was no significant difference in preference between inoculated and control treatments for tohya. Kudzu bugs significantly preferred inoculated black jet and viking and uninoculated butterbean soybean varieties. It was expected that kudzu bugs would have preferred inoculated soybeans across all varieties; however, the varied preferences in the experiment was unexpected because soybeans with nodules are assumed to have a higher nutritional content than those without