Changes in the Physiological and Morphometric Characteristics and Biomass Distribution of Forage Grasses Growing under Conditions of Drought and Silicon Application

Abstract

Research on mitigating the effects of water scarcity by applying silicon to perennial grasses is still insufficient. This study was conducted to investigate the effect of spring and summer droughts and silicon applications on gas exchange parameters; the morphometric characteristics of root systems; and the biomass distribution of Festulolium braunii, Festuca arundinacea, and Lolium perenne cultivars. Plants were treated with a drought during the tillering phase once a year (during spring or summer regrowth) for 21 days. Foliar nutrition with silicon was applied twice under the drought conditions. Grasses in a pot experiment were cut three times during vegetation. The plants that were exposed to the drought had lower values of the gas exchange parameters than those that were well watered. The beneficial effect of silicon was related to the reduction of excessive water loss through transpiration during the spring drought. Under the drought and silicon applications, the water use efficiency, root dry mass, and length increased compared to the control. Moreover, silicon increased the proportion of both the finer and thicker roots in F. braunii and L. perenne, while the distribution of the root diameter changed least in the more resistant F. arundinacea. Silicon also reduced the carbon content in the roots and increased root carbon accumulation. Our results indicated that Si may help perennial forage grasses cope better with drought stress. This was due to the allocation of carbon to the roots to develop the fine root network, increasing the length and root biomass and improving the water use efficiency.

Preference of Silicon Accumulation on the Shaded Foliage of Tree Crowns and its Implications for Juniperus chinensis L

“…4) and is consistent with the optimal allocation theory (McKey 1974). Similar results have con rmed the negative correlation between foliar Si and carbon concentrations (Klotzbücher et al 2018) and the reduced carbon content in Si applications (Mastalerczuk et al 2022). In addition, plants also adapt to minimize available light through the enhancement of light capture, for example, via the increased synthesis of chlorophyll and protein (Atanasova et al 2003).…”

Germination of Lolium perenne and Medicago Species under the Conditions of Drought and Silicon Application as Well as Variable pH and Medicago sativa Root Extracts

“…The same was also observed when the seeds of the examined species were germinated as a mixture. Our other pot studies [ 40 ] have shown that while drought conditions reduced the root lengths of L. perenne in the tillering phase by approx. 40–50% compared to control conditions, the application of Si significantly increased the length of the roots (approx.…”

Mitigating drought stress in wheat plants (Triticum Aestivum L.) through grain priming in aqueous extract of spirulina platensis

“…The diminution in flag leaf biomass, water content, succulence degree, succulence, succulence quotient, area, and specific area can be ascribed to several drought-induced phenomena: (i) a decline in cellular turgor pressure, ostensibly obstructing cell division, enlargement, and differentiation [ 59 ], (ii) an encumbered assimilate supply, largely attributed to the limitations imposed on critical plant processes, predominantly photosynthesis [ 60 ], (iii) a perturbation in nutrient availability, concomitant with a diminished water supply [ 61 ], and/or, (iv) a temporal shift, manifesting as delayed leaf emergence and precipitated leaf senescence [ 62 ].…”