Forage quality and physiological performance of mowed alfalfa (Medicago sativa L.) subjected to combined light quality and drought

Abstract

Alfalfa (Medicago sativa) can dwell in water-deficient habitats, where it is difficult to predict dry mass (DM) production and forage quality due to understory transmittance. Mowing is a recommended practice for alfalfa populations under drought, but its effect on forested land receives less attention. In a controlled indoor experiment, we found that drought better reduces shoot DM weight and crude fiber content (CFi) in blue light (33.7% red, 48.5% green, and 17.8% blue lights) than red light (71.7% red, 13.7% green, and 14.6% blue lights). Mowing decreases carbon (C) isotope signature (δ13C), CFi, and total C content in shoots but increases their accumulations in DM, nonstructural carbohydrates, and crude fat content (CFa). The results also demonstrated that mown alfalfa has higher starch content when exposed to green light (26.2% red, 56.4% green, and 17.4% blue lights) compared to the other two spectra. Multiple factorial regression indicated that higher soluble sugar content accounted for the increase of CFa and DM weight for CFi. Overall, mowing in blue-light–enriched understory stands is recommended and produces high-forage–quality alfalfa, which can be used as a lowered crude fiber component.

Natural Bioactive Substances in Fruits of Aronia melanocarpa (Michx.) Elliott Exposed to Combined Light-Type, Chitosan Oligosaccharide, and Spent Mushroom Residue Treatments

“…Chitosan oligosaccharide (CO) can be widely obtained from seafood wastes and used as a plant-growth regulator. The direct addition of CO can increase drought assistance by controlling stomatal conductance in Buddhist pine ( Podocarpus macrophyllus ) seedlings [ 52 ]. The CO addition can also improve the ability of nutrient uptake and utilization in Buddhist pine [ 29 , 51 ] and fragrant rosewood ( Dalbergia odorifera ) seedlings [ 53 ].…”

Drought stress tolerance and metabolomics of Medicago sativa induced by Bacillus amyloliquefaciens DGL1

“…Although alfalfa is highly drought tolerant, it requires a large amount of water for growth; thus, cultivation in arid and semi-arid areas is overly dependent on irrigation, and the growth process is susceptible to drought stress ( Attram et al., 2016 ). The growth indicators of alfalfa, such as stem length, stem thickness, number of tillers, and leaf area, decrease after being subjected to drought stress ( He et al., 2022 ). Alfalfa growth and physiological characteristics can also be limited.…”

Light-Emitting Diodes Modify Medicinal Quality of Mown Rabdosia rubescens, with Changes in Growth, Physiology, and Antioxidant Activity, under Drought Stress

“…However, perennial roots reserve essential substances that can support and fuel annual shoot sprouting. Mowing has been proven to be a feasible practice that can promote annual sprouting from perennial roots help the plants to cope with the shock of drought’s effects [ 19 , 20 ]. Mowing forage plants can improve their water-use efficiency through modulating stomatal conductance and gas exchange [ 19 ].…”

“…Mowing has been proven to be a feasible practice that can promote annual sprouting from perennial roots help the plants to cope with the shock of drought’s effects [ 19 , 20 ]. Mowing forage plants can improve their water-use efficiency through modulating stomatal conductance and gas exchange [ 19 ]. It has been identified that mowing can increase the synthesis and accumulation of secondary metabolites in annual shoots of medicinal plants [ 16 ].…”

“…For example, a spectrum with a 70%:30% red-to-blue light ratio can increase resistance to drought stress in lemon balm ( Melissa officinalis ) plantlets [ 24 ]. LED lighting was found to interact with mowing, and both factors had combined effects on the development of newly sprouted shoots [ 16 , 19 ] and nutrient utilization [ 16 ]. The best strategy for setting up a solid spectrum of artificial light with other cultural practices to help plants cope with drought is still undetermined.…”