The Allelopathic Potential of Rosa blanda Aiton on Selected Wild-Growing Native and Cultivated Plants in Europe

Effects of 13C isotope-labeled allelochemicals on the growth of the invasive plant Alternanthera philoxeroides

The secondary metabolites of indigenous plants have significant allelopathic inhibitory effects on the growth and development of invasive alien plants. Methyl palmitate (MP) and methyl linolenate (ML) were used as exogenous allelopathic substances. The research investigated the differences of inhibitory effects of MP and ML on the growth of seedlings of Alternanthera philoxeroides, and calculated their morphological characteristics, biomass, physiological indicators and the response index (RI). The synthetical allelopathic index (SE) of 1 mmol/L MP was the smallest (- 0.26) and the allelopathic inhibition was the strongest; therefore, it was selected as a 13C-labeled allelochemical. The distribution of 1 mmol/L MP in different parts of A. philoxeroides and the correlation between the biomass ratios of roots, stems and leaves and the 13C content were studied by 13C stable isotope tracing experiments. Atom percent excess (APE) between roots, stems and leaves of A. philoxeroides treated with 1 mmol/L MP were significantly different in terms of magnitude, with leaves (0.17%) > roots (0.12%) > stems (0.07%). The root, stem and leaf biomass ratios of invasive weeds had great significant positive correlation with 13C content (p < 0.01, R2 between 0.96 and 0.99). This current research provides a new idea and method for the control of A. philoxeroides, but large-scale popularization remains to be studied.

Trial Protocol for Evaluating Platforms for Growing Microgreens in Hydroponic Conditions

The hydroponic production of microgreens has potential to develop, at both an industrial, and a family level, due to the improved production platforms. The literature review found numerous studies which recommend procedures, parameters and best intervals for the development of microgreens. This paper aims to develop, based on the review of the literature, a set of procedures and parameters, included in a test protocol, for hydroponically cultivated microgreens. Procedures and parameters proposed to be included in the trial protocol for evaluating platforms for growing microgreens in hydroponic conditions are: (1) different determinations: in controlled settings (setting the optimal ranges) and in operational environments settings (weather conditions in the area/testing period); (2) procedures and parameters related to microgreen growth (obtaining the microgreens seedling, determining microgreen germination, measurements on the morphology of plants, microgreens harvesting); (3) microgreens production and quality (fresh biomass yield, dry matter content, water use efficiency, bioactive compound analysis, statistical analysis). Procedures and parameters proposed in the protocol will provide us with the evaluation information of the hydroponic platforms to ensure: number of growing days to reach desired size; yield per area, crop health, and secondary metabolite accumulation.