Plant extracts - importance in sustainable agriculture

Abstract

Plants due to the high content of various bioactive compounds are the main raw material for production of valuable, and useful bio-products (e.g., food, cosmetics, medicines, biostimulants, biopesticides, and feed). Different plant parts, for instance: seeds, fruits, flowers, stems, leaves, and roots can be used for their manufacture. Nowadays, there is a clear need to develop new, efficient, and environmentally safe methods of stimulation of plant, growth and crop protection. Plant-based extracts are new, natural, and multi-compounds products that could be used for these purposes. They possess antifungal, antimicrobial, antiparasitic, antiprotozoal, antioxidant, medicinal, aromatic, and anti-inflammatory properties. This group of natural products has the potential to become a new generation of bio-products suitable for use in sustainable agriculture. The purpose of this review is to provide an overview of the literature describing the impact of plant-derived extracts/biostimulants (PDBs) on crops grown in controlled, and real conditions as well as under various abiotic and biotic stresses; the extraction methods used to obtain PDBs, and the specific constituents responsible for their biostimulating activity. The application of these bio-products could be beneficial for sustainable production, due to several advantages, such as low toxicity to humans and the environment, enhanced resistance of cultivated plants to biotic and abiotic stress, increased yields and quality of crops, as well as the reduction in the use of mineral fertilisers and pesticides. However, deeper cooperation between industrial and academic research is required to accelerate the development of new environmentally safe solutions for future agriculture.
 Highlights - Higher plants constitute a rich source of various bioactive compounds for the production of useful natural products. - The importance of the proper choice of extraction method and solvent to process and preserve the desired substances.- Plant extracts as biostimulants and plant protection products for use in modern and sustainable agriculture. - The positive effects of plant-based extracts on plants cultivated under normal and unfavourable conditions.- Plant extracts as a new generation of eco-friendly products for the increment of the production of high-quality food.

Photosynthetic Pigments and Biochemical Response of Zucchini (Cucurbita pepo L.) to Plant-Derived Extracts, Microbial, and Potassium Silicate as Biostimulants Under Greenhouse Conditions

“…It is noted that there is an effect of the use of biostimulants on the metabolism of plants and the final quality (Colla et al, 2015 ). Plant growth, quality, tolerance to abiotic and biotic stresses, photosynthesis, and using nutrients, fertilizers, and water are able to be enhanced by plant-derived biostimulants (PDBs) by modulating plant biochemical, molecular, and physiological processes (Rouphael and Colla, 2020b ; Godlewska et al, 2021 ; Mosa et al, 2021b ). Our previous work (Hassan et al, 2021 ) showed that the most abundant phenolic compounds in Eucalyptus camaldulensis LE were pyrogallol, caffeic acid, and p -coumaric acid, in Citrus sinensis LE were syringic and ferulic acids, and in Ficus benghalensis were gallic, p-coumaric, and syringic acids.…”

“…In addition, phenolic acids and flavonoids often play the important roles in the plant's defense against disease (Sarker and Oba, 2018 ). However, the plant extracts can be considered a good source of natural antioxidants and antimicrobial in both in vitro and in vivo (Di Mola et al, 2019 ; Souri and Bakhtiarizade, 2019 ; Godlewska et al, 2021 ). The raw materials resulting from the pruning processes of Eucalyptus camaldulensis, Citrus sinensis , and Ficus benghalensis trees are readily available in high quantities in Egypt.…”

Effects of Biostimulants on the Chemical Composition of Essential Oil and Hydrosol of Lavandin (Lavandula x intermedia Emeric ex Loisel.) Cultivated in Tuscan-Emilian Apennines

“…In particular, EO biosynthesis was demonstrated to be strictly related to agro-climatic, soil conditions, light exposure, genetic variability, and development stage of the whole plant [11,12]. Moreover, in recent years, the application of plant extracts or biostimulants has been attempted on aromatic plants cultivation [13][14][15][16], also allowed in organic farming. Biostimulants are compounds able to enhance plant nutrition, stress tolerance, and/or plant metabolic processes in order to improve crop quality.…”

Time-course gene expression profiling data of Triticum aestivum treated by supercritical CO2 garlic extract encapsulated in nanoscale liposomes

“…Using plant-based extracts, such as garlic extract as the plant biostimulant (PB) is effective to enhance the sustainability of crop protection and may increase defense responses to abiotic and biotic stresses [ [1] , [2] , [3] – 4 ]. Supercritical CO 2 extraction technique and nanoscale drug delivery system (liposomes composed of plant-derived lipids) have been shown to more efficient penetration and translocation than many liquid organic solvents [ [5] , [6] – 7 ].…”