Plant-Based Protein Hydrolysate Improves Salinity Tolerance in Hemp: Agronomical and Physiological Aspects

Abstract

Hemp (Cannabis sativa L.) is a multipurpose plant attracting increasing interest as a source for the production of natural fibers, paper, bio-building material and food. In this research we studied the agronomical performance of Cannabis sativa cv. Eletta Campana irrigated with saline water. Under those conditions, we tested the effect of protein hydrolysate (PH) biostimulant application in overcoming and/or balancing deleterious salinity effects. The results of the diverse treatments were also investigated at the physiological level, focusing on photosynthesis by means of a chlorophyll a fluorescence technique, which give an insight into the plant primary photochemical reactions. Four salinity levels of the irrigation solution (fresh water–EC0, and NaCl solutions at EC 2.0, 4.0 or 6.0 dS m−1, EC2, EC4 and EC6, respectively) were combined with 2 biostimulant treatments (untreated (control) or treated with a commercial legume-derived protein hydrolysate (LDPH)). The increasing salinity affected plant photochemistry resulting in lower plant growth and seed production, while the LDPH biostimulant showed a protective effect, which improved crop performance both in control and in salinity conditions. The LDPH treatment improved seeds yield (+38.6% on average of all treated plants respect to untreated plants), as well as residual biomass, relevant in fiber production.

Mitigation of High-Temperature Damage by Application of Kaolin and Pinolene on Young Olive Trees (Olea europaea L.): A Preliminary Experiment to Assess Biometric, Eco-Physiological and Nutraceutical Parameters

“…Before the end of the experiment, chlorophyll a fluorescence measurements were recorded in the field on 30 min dark-adapted leaves using a PAR-FluorPen FP 110/D portable fluorimeter (Photon Systems Instruments, Drásov, Czech Republic) equipped with detachable leaf-clip. Measurements occurred at 9 a.m. and 1:30 p.m., for a one hour lap each, according to the procedure reported by Mola et al [29]. Fluorescence data were analyzed by the FluorPen software ver.…”

Assessment of Yield and Nitrate Content of Wall Rocket Grown under Diffuse-Light- or Clear-Plastic Films and Subjected to Different Nitrogen Fertilization Levels and Biostimulant Application

“…Conditions of high diffuse radiation elicit a plant production increase as a result of a higher efficient yield per unit of PAR [30]. In these conditions, radiation comes from all the directions and can penetrate deeper into the canopy that is usually shaded, thus covering it uniformly [31] and increasing the light use efficiency and consequently yield, since the photosynthesis is the main factor influencing productivity [32]. In addition, some authors claimed that plants cultivated under diffuse light suffer fewer stress events related to water and heat [33,34].…”

Impact of Ecklonia maxima Seaweed Extract and Mo Foliar Treatments on Biofortification, Spinach Yield, Quality and NUE

“…One of the most pioneeristic agronomic practices to meet these challenges is the use of plant biostimulants which can elicit growth and development, productivity, abiotic stress tolerance and quality of plants [3,4]. Several authors [5][6][7][8][9][10][11][12] have reported that biostimulants can promote primary and secondary metabolism in vegetables, modulating micro-and macronutrient uptake and assimilation, buildup of phytochemicals and tolerance to abiotic distresses. Among plant biostimulants, seaweed extracts (SEs), especially the brown macro-algae, are often used for their content in signaling molecules such as polysaccharides, betaines, macroand micronutrients and phytohormones which enhance plant performance [13,14].…”