Identification of Pueraria spp. through DNA barcoding and comparative transcriptomics

Background Kudzu is a term used generically to describe members of the genus Pueraria. Kudzu roots have been used for centuries in traditional Chinese medicine in view of their high levels of beneficial isoflavones including the unique 8-C-glycoside of daidzein, puerarin. In the US, kudzu is seen as a noxious weed causing ecological and economic damage. However, not all kudzu species make puerarin or are equally invasive. Kudzu remains difficult to identify due to its diverse morphology and inconsistent nomenclature. Results We have generated sequences for the internal transcribed spacer 2 (ITS2) and maturase K (matK) regions of Pueraria montana lobata, P. montana montana, and P. phaseoloides, and identified two accessions previously used for differential analysis of puerarin biosynthesis as P. lobata and P. phaseoloides. Additionally, we have generated root transcriptomes for the puerarin-producing P. m. lobata and the non-puerarin producing P. phaseoloides. Within the transcriptomes, microsatellites were identified to aid in species identification as well as population diversity. Conclusions The barcode sequences generated will aid in fast and efficient identification of the three kudzu species. Additionally, the microsatellites identified from the transcriptomes will aid in genetic analysis. The root transcriptomes also provide a molecular toolkit for comparative gene expression analysis towards elucidation of the biosynthesis of kudzu phytochemicals.

Noxious Weed Views and Behaviors in Montana after 25 Years of Public Education

In 1994 a general population survey was conducted to evaluate Montanans’ knowledge about noxious weeds, and results from that survey launched an ongoing statewide education campaign. In 2019 we conducted another general population survey to assess the views and behaviors of Montanans as they relate to noxious weeds and to identify new approaches for disseminating noxious weed information. We also asked questions to evaluate changes over the 25-year period, though our ability to make direct comparisons is subject to limitations. We implemented a mail-based survey in March through May 2019. The response rate was 18%, with 830 responses from 4,582 valid mailing addresses. Just under half (48%) of respondents report “little” or “no” knowledge about noxious weeds, which would constitute a 19-point improvement since 1994. A large majority (68%) of respondents indicate that noxious weeds are a “serious” or “very serious” problem, and appreciation for the range of negative impacts associated with noxious weeds is considerable. Most respondents (61%) identify humans as contributing “a lot” to noxious weed spread, and respondents report that their behaviors to prevent the spread of noxious weeds have increased over time. While the 1994 respondents rated television, newspaper, and radio as the best ways to disseminate information about noxious weeds, respondents now also recognize methods such as websites and social media pages as effective. Our survey identifies a need for increased educational messaging for women and people in the 18-39 age group. Overall, our results indicate that individuals who have seen different forms of advertisements and have participated in educational programs are more likely to consider noxious weeds a serious problem and to engage in behaviors to stop their spread.

Parthenium hysterophorus: Weed of Pharmacological Importance

Parthenium hysterophorus, often known as congers grass, is a noxious weed that is a member of the Asteraceae family of plants. Its natural habitats include the areas surrounding the Gulf of Mexico, Central America, Southern North America, the West Indies, and Central South America, among other places. Congress grass has risen to become one of the world’s seven most destructive and deadly weeds, according to the World Health Organization. This invasive plant is also a significant concern in India. It is responsible for a variety of illnesses and allergies in both people and animals. Aside from that, there is some potential for this plant to be used as an insecticide, herbicide, fungicide, wood preservative, anti-amoebic, and even for medicinal purposes. If any species, particularly an invasive weed, is to be evaluated for its ability to benefit living organisms, it is necessary to have a thorough understanding of both its positive and negative impacts. As a result, this review paper is an attempt to describe the present state of knowledge regarding the hazardous and helpful effects of Parthenium hysterophorus on people and animals.

Herbicides for lamb's quarters control in soybean crops

The results of the study of toxicity level for the lamb's quarters (Chenopodium album L.) of well-known herbicides used in soybean crops as well as herbicides promising for soybean production in the Far East are presented. Lamb's quarters (Chenopodium album L.) is a highly noxious weed species that is widespread in the south of the region. Weediness monitoring conducted in 2006-2020 showed that this species was present in the Primorsky Territory on 63-100% of fields occupied by soybeans with an average growth density of 3-117 pcs/m2. In 2013-2020 in a series of experiments, conducted in the conditions of the vegetation house and on the experimental fields of the institute, the toxicity level for Common lamb's quarters was determined by 20 herbicides (based on 14 active substances) used in soybean crops. It was found that the control of this weed species is most effective when applying herbicides in the soil and treating plants with a height of up to 4-11 cm at the early stages of development - 1-3 pairs of leaves. Reliable suppression of lamb's quarters in experiments was provided by the soil (before sowing or before soybean seedlings) use of herbicides containing active substances metribuzin, imazetapir, trifluralin, pendimetalin and acetochlor. Among the active ingredients of the tested foliar herbicides, fomesafen, combinations of bentazone + acifluorfen and imazamox + chlorimuron-ethyl were the most toxic for lamb's quarters. It is recommended to use the following herbicidal preparations to control the spread of lamb's quarters: before sowing or sprouting of soybeans - Lazurit, Zenkor Ultra, Pivot, Proponit, Fabian; for processing vegetative plants - Flex, Galaksi Top, Concept, Classic Forte (Harmony Classic), Proponit.

Opposing effects of plant growth regulators via clonal integration on apical and basal performance in alligator weed

Aims Invasive plants are a major threat to biodiversity and may adversely affect food security. Clonal integration enables the sharing of resources between connected ramets and can enhance plant performance in many invasive species. However, few studies have examined the role of clonal integration when weeds are exposed to plant growth regulators (PGRs). PGRs are used extensively in agriculture and may affect nearby weeds through soil leaching, erosion, and runoff. Our aim was to investigate the effects of clonal integration on growth in a noxious weed, Alternanthera philoxeroides (alligator weed), in response to two PGRs frequently used in agriculture, gibberellins (GA) and paclobutrazol (PAC). Methods Ramets of A. philoxeroides were propagated in the greenhouse, and treated with PGRs. PGRs were applied to the older ramets (i.e., ‘basal’ part), with half of the plants having the stems between the apical (younger) and basal parts left connected, while the remaining plants had the stems between the two parts severed. Following the growing period, plants were measured for growth traits. Important Findings We found that GA and PAC had contrasting effects on plant growth. GA significantly promoted above-ground growth of the apical ramets via clonal integration. Alternatively, PAC inhibited above-ground growth in the basal and apical parts, and enhanced below-ground growth of the basal and apical ramets through clonal integration. Our results highlight how clonal integration can promote growth in A. philoxeroides following the application of PGRs, which is likely an important mechanism for this species to invade new environments.

Standardized invasive species terminology for effective education of Floridians

In this document we introduce a standardized set of seven terms compiled by the members of the UF|IFAS Invasive Species Council that can describe most situations involving invasive species. We do so to promote a common language among Florida’s Extension and outreach professionals. This will limit confusion caused by excessive jargon used to describe invasive species and the fact that much of this jargon is used incorrectly. This confusion hinders stakeholder understanding of environmental and economic impacts caused by invasive species which can prevent stakeholders from adopting behaviors that can both limit the introduction of new invasive species and decrease the impacts of those already established. The seven terms we propose are “native”, “nonnative”, “introduced”, “established”, “invasive”, “nuisance”, and “range change”. We also list six terms to avoid due to their tendency to create confusion and/or be misused and misinterpreted (“native invasive”, “invasive exotic”, “invasive weed”, “alien”, “foreign”, and “nonindigenous”) as well as precise definitions of common legal terms (“noxious weed”, “injurious”, “prohibited”, and “conditional/restricted”). By speaking this common language, Florida’s Extension and outreach professionals can deliver a simplified and unified message about the impacts of invasive species and how to best prevent and control them, potentially increasing the environmental and socioeconomic benefits of invasive species Extension and outreach programs.