The Evaluation of Phenolic Acids and Flavonoids Content and Antiprotozoal Activity of Eryngium Species Biomass Produced by Biotechnological Methods

Three species from the Eryngium L. genus—E. campestre, E. maritimum, and E. planum, plants with a rich chemical composition, were selected for phytochemical and biological studies. The applied biotechnological methods allowed to obtain the biomass of these rare or protected species in the form of multiplied shoots (stationary system) and roots cultured in a liquid medium (agitated system). In the extracts from the raw material obtained under in vitro conditions, the content of selected phenolic acids and flavonoids (HPLC-DAD method) as well as the total of polyphenols (Folin–Ciocalteu assay) were quantified. The highest amount of all phenolic compounds was found in extracts from E. planum roots (950.90 ± 33.52 mg/100 g d.w.), and the lowest from E. campestre roots (285.00 ± 10.07 mg/100 g d.w.). The quantitatively dominant compound proved to be rosmarinic acid. The highest amounts were confirmed for E. planum root extract (694.58 mg/100 g d.w.), followed by E. planum (388.95 mg/100 g d.w.) and E. campestre (325.85 mg/100 g d.w.) shoot extracts. The total content of polyphenols was always increased in the biomass from in vitro cultures in comparison to the analogous organs of intact plants of each species. The obtained extracts were assessed for antiprotozoal activity against Acanthamoeba sp. The strength of biological activity of the extracts correlated with the content of phenolic compounds. To our knowledge, this is the first report on the amoebicidal activity of E. campestre, E. maritimum, and E. planum extracts from biomass produced by biotechnological methods.

GhAIL6, a Member of the AP2 Family Gene, Promotes Somatic Embryogenesis in Cotton.

Background Somatic embryogenesis (SE) is the process by which plant somatic cells are cultured in vitro without fertilization to regenerate embryos and develop into intact plants, the difficulty of cotton regeneration has severely limited functional gene research and transgenic breeding. The AP2 family is a relatively large family of transcription factor genes that regulate the process of growth and development, but the role of Aintegumenta-Like6 ( AIL6) in cotton SE has not been reported. Methods The 35S::AIL6:GR vector was constructed and transformed into cotton JH713 by Agrobacterium-mediated method, after 3 years of self-breeding, stable genetic T3 generation positive plants were obtained, identified by Southern, and three lines were selected for the following regeneration experiments.Results The results showed that overexpression of GhAIL6 significantly inhibited the proliferation of callus during the first 30 days, and promoted the embryogenic callus production at about 45 days.Couclusion Our results indicated that GhAIL6 was a key regulator of cotton SE, overexpression of GhAIL6 helped to improve the regeneration efficiency of cotton SE

Novel Encapsulated Herbicide Delivery Mechanism: Its Efficacy in Mimosa Bush (Vachellia farnesiana) Control

Mimosa bush (Vachellia farnesiana) is an invasive woody weed widely distributed in Australia. While it can be controlled using several mechanical and chemical techniques, this study evaluated a novel herbicide delivery mechanism that minimizes the risk of spray drift and potential non-target damage. This method, developed by Bioherbicides Australia, involves the implantation of encapsulated granular herbicides into the stem of intact plants or into the stump after cutting off plants close to ground level (cut stumps). Trials were implemented near Moree (New South Wales, Australia) on intact (two experimental runs) plants and cut stumped (two experimental runs) plants. For each trial, an untreated control plus the conventional basal bark application of a liquid formulation of triclopyr + picloram mixed with diesel was included for comparison. Encapsulated glyphosate, aminopyralid + metsulfuron-methyl, hexazinone and clopyralid were also tested in all trials. In addition, encapsulated triclopyr + picloram, and metsulfuron-methyl were included in one of the intact plant trials. Aminopyralid + metsulfuron-methyl was consistently most effective on cut stump and intact plants, whilst clopyralid provided highest mortality when applied to cut stumps and single-stemmed intact plants. Particularly for multi-stemmed intact plants, clopyralid should be applied to each stem. Overall, the highest efficacy was achieved on single stemmed plants, but with further refinement of the technique, it should be possible to achieve similar results for multi-stemmed individuals. This method resulted in a reduction in the use of herbicide and environmental contamination while significantly improving speed of treatment.

Features of the strawberry field repository formation

For the successful functioning of a breeding and nursery center of scientific and practical work with fruit and small fruit crops, an important task is to create repositories, including thosein the field. A field repository is a plant gene bank based in accordance with international standards on planting material that is free from dangerous pathogens, including viruses, representing tested for productivity typical plants.For the purpose of a comparative study of promising varieties, hybrids and clones-candidates for original plants, a field repository and mother plantation of strawberries clones and varieties have been created on the territory of the Federal Horticultural Research Center for Breeding, Agrotechnology and Nursery.As a result of research in 2015-2020, 386 high-yielding strawberry plants were selected and tested for the main harmful viruses using diagnostic kits from “Loewe” firm (Germany). The prevalence of harmful Arabis mosaic virus (ArMV), Raspberry ringspot virus (RpRSV), Tomato black ring virus (TBRV), Strawberry latent ringspot virus (SLRSV), Cucumber mosaic virus (CMV) in strawberry plantations depended on the area cultivation, varietal composition of plantings and ranged from 31 to 69 %. The prevalence of viruses RpRSV (up to 36 %), TBRV (up to 31 %) and CMV (up to 22 %) was established. The high efficiency of dry-air thermotherapy for the recovery of strawberries with the number of virus-free intact plants of 56 % has been shown.A genebank of "candidates for original plants" has been formed from 234 strawberry plants of 39 varieties and hybrids, which, after confirming their status by PCR, will be transferred to the category of "original plants".

FLAVONOIDS OF IRIS SIBIRICA L. GROWN IN VITRO CULTURE

The aim of this study was to evaluate the effect of 6-benzylaminopurine (BAP) separately and in interaction with auxins on the change in the qualitative and quantitative composition of flavonoids in the raw materials of regenerating plants Iris sibirica L. Cambridge grade in comparison with aeroponic and intact raw materials using the method of high-performance liquid chromatography. Raw materials of I. sibirica Cambridge variety obtained in vitro culture had a richer qualitative composition of flavonoids than intact plants. The dependence of the accumulation of flavonoids on the concentration of 6-benzylaminopurine in nutrient media was noted. The presence of 13 compounds was observed in extracts of 70% ethyl alcohol from regenerating plants grown at the lowest concentration of BAP (1.0 µM) within the experiment. In quantitative terms, the flavonoid apigenin was maximally determined on a medium with BAP 1 µM, and kaempferol - on media with BAP 5.0 µM, supplemented with auxins. For a medium with 7.5 µM BAP, the lowest variety of compounds was observed (9) and the lowest kaempferol content. Auxins influenced the synthesis of flavonoids. The amount of flavonoids in all variants of the experiment increased by an average of 13% in the presence of auxins. The stages of the technological process of obtaining raw materials I. sibirica Cambridge variety on the basis of clonal micropropagation and cultivation in aeroponics conditions allowed to obtain raw materials that do not contain heavy and toxic metals, are not infected with pathogens and pests. With 1 m2 of useful area of aeroponics for 1 year, it is possible to collect 5 times more raw materials than with field cultivation. According to the qualitative composition of phenolic compounds, aeroponic raw materials are identical to intact plants.

The Effect of Cutting and Waterlogging on Plant-Related CO2 and N2O Fluxes Associated with the Invasive N-Fixing Species Gunnera tinctoria

The overall impact that plant invasions have on greenhouse gas emissions (GHG) by plant-mediated effects and how these interact with environmental and management factors is largely unknown. To address this, we report on the effects of leaf removal and waterlogging, either singularly or in combination, on the fluxes of CO2 and N2O associated with the invasive species Gunnera tinctoria. Both the removal of leaves with and without flooding resulted in higher CO2 emissions due to reductions in photosynthesis. Whilst waterlogging alone was also associated with a reduction in photosynthesis, this was slower than the effect of leaf removal. Significant N2O emissions were associated with intact plants, which increased immediately after leaf removal, or seven days after waterlogging with or without leaf removal. We found positive correlations between CO2 and N2O emissions and petiole and rhizome areas, indicating a size-dependent effect. Our results demonstrate that intact plants of G. tinctoria are a source of N2O emissions, which is enhanced, albeit transiently, by the removal of leaves. Consequently, management interventions on invasive plant populations that involve the removal of above-ground material, or waterlogging, would not only reduce CO2 uptake, but would further compromise the ecosystem GHG balance through enhanced N2O emissions.

Strigo-D2 - a bio-sensor for monitoring the spatio-temporal pattern of strigolactone signaling in intact plants

Strigolactones (SLs) are a class of plant hormones modulating developmental programs in response to endogenous and exogenous stimuli and mediating biotic interactions. However, a comprehensive view on the spatio-temporal pattern of SL signaling has not been established and tools for a systematic in planta analysis do not exist. Here, we present Strigo-D2, a genetically encoded ratiometric SL signaling sensor, allowing the examination of SL signaling distribution with cellular resolution and its rapid response to altered SL levels in intact plants. By monitoring the abundance of a truncated and fluorescently labeled SUPPRESSOR OF MAX2 1-LIKE 6 (SMXL6) protein, a proteolytic target of the SL signaling machinery, we show that all cell types investigated have the capacity to respond to changes in SL levels but with very different dynamics. In particular, SL signaling is pronounced in vascular cells but low in guard cells and the meristematic region of the root. We also show that other hormones leave Strigo-D2 activity unchanged indicating that initial SL signaling steps work in isolation from other hormonal signaling pathways. Specificity and spatio-temporal resolution of Strigo-D2 underline the value of the sensor for monitoring SL signaling in a broad range of biological contexts and with highly instructive analytical depth.

Exogenous Treatments to Enhance Splice-Grafted Watermelon Survival

This study evaluated the use of splice grafting as a propagation strategy for watermelon. In experiment 1, the treatments consisted of sucrose, antitranspirant A, antitranspirant B, auxin (indole-3-butyric acid (IBA)) at two concentrations (10 and 20 mgL−1), plus a water control. The survival (%) of splice-grafted watermelon plants differed due to the number of days after grafting and treatment (p < 0.0001, for both). At 21 days after grafting, plants treated with sucrose and antitranspirant A, and sucrose and antitranspirant A with 10 mgL−1 auxin had 90% and 88% survival, respectively, whereas the graft survival was 18% for plants treated with water. Experiment 2 included the three top performing treatments from experiment 1 and a water control treatment, applied to both root-intact and root-excised rootstocks. There was a significant difference in survival (%) of splice-grafted watermelon due to root treatments, exogenous treatments, and the number of days after grafting (p < 0.0001, for all). At 21 days after grafting, survival for root-excised grafted plants was 11% lower compared to root-intact plants. Plants treated with sucrose and antitranspirant A, and sucrose and antitranspirant A with 10 mgL−1 auxin had 87% and 86% survival, respectively, whereas plants treated with water had 14% survival. The external application of auxin applied to rootstock seedlings does not appear to be cost-effective; however, other products should be evaluated.

More than a stick in the mud: Eelgrass leaf and root bacterial communities are distinct from those on physical mimics

We examine the role of physical structure vs. biotic interactions in structuring host-associated microbial communities on a marine angiosperm, Zostera marina, eelgrass. Across several months and sites, we compared microbiomes on physical mimics of eelgrass roots and leaves to those on intact plants. We find large, consistent differences in the microbiome of mimics and plants, especially on roots, but also on leaves. Key taxa that are more abundant on leaves have been associated with microalgal and macroalgal disease and merit further investigation to determine their role in mediating plant-microalgal-pathogen interactions. Root associated taxa were associated with sulfur and nitrogen cycling, potentially ameliorating environmental stresses for the plant. Our work identifies targets for future work on the functional role of the seagrass microbiome in promoting the success of these angiosperms in the sea.