Silicon as a Sustainable Option to Increase Biomass With Less Water by Inducing Carbon:Nitrogen:Phosphorus Stoichiometric Homeostasis in Sugarcane and Energy Cane

Abstract

Climate change has prolonged periods of water deficit in sugarcane and energy cane crops. This condition induces an imbalance of the carbon (C): nitrogen (N): phosphorus (P) stoichiometric homeostasis, impairing accumulated nutrients from being converted into biomass. Silicon (Si) supplementation can mitigate the damage caused by water deficit in plants by improving the C:N:P balance, increasing C, N, and P use efficiencies and the biomass conversion, and reducing climate change effects on crops. This study assesses the beneficial effects of Si applied through fertigation associated with foliar spraying on the alleviation of damage caused by severe water deficit in sugarcane and energy cane for intermediate and long periods. In addition, the effects in maintenance of nutritional homeostasis we assessed and C, N, and P use efficiencies on sugarcane and energy cane under those conditions were increased. Four experiments were conducted during the first growth cycle of each species. The effect of fertigation associated with Si foliar spraying was evaluated by applying Si only during the seedling formation phase in sugarcane and energy cane grown under severe water deficit for 60 days after transplanting (intermediate period). Then, the effect of Si applied during seedling formation and supplemented after transplanting was evaluated in sugarcane and energy cane grown under severe water deficit for 160 days after transplanting (long period). The Si supply decreased C contents, modified the C:N:P ratio, and increased C, N, and P use efficiencies in plants of both species under water deficit at the intermediate and long periods after transplanting. The effects of applying Si through fertigation associated with foliar spraying during seedling formation mitigated the damage caused by severe water deficit in the intermediate period, which was mainly observed in sugarcane. When supplemented with Si after transplanting, the mitigating effects occurred in both species under severe long period water deficit. Therefore, the Si supply through fertigation associated with foliar spraying is a viable alternative to provide Si to the plant. It also comes with beneficial effects that partially reverse the damage to nutritional homeostasis and increase nutritional efficiency in plants under severe water deficit.

Impact of Si on C, N, and P stoichiometric homeostasis favors nutrition and stem dry mass accumulation in sugarcane cultivated in tropical soils with different water regimes

“…Evidence indicates greater Si use from the soil solution by Siaccumulating plants, such as sugarcane (Saccharum officinarum L.) (Teixeira et al, 2021(Teixeira et al, , 2022, as they have efficient carriers for Si absorption (LSi1, LSi2, and LS6) (Yamaji and Jian Feng, 2009). However, studies on this species and most crops focus on plants grown under abiotic (Verma et al, 2020b;Sousa Junior et al, 2021;Teixeira et al, 2021) and biotic stress conditions (Tomaz et al, 2021).…”

New approaches to the effects of Si on sugarcane ratoon under irrigation in Quartzipsamments, Eutrophic Red Oxisol, and Dystrophic Red Oxisol

“…Studies with application of Si via fertigation in sugarcane crops with deficient irrigation are restricted [ 13 , 14 , 31 – 33 ]. This raises concerns, as it may decrease the absorption of Si depending on the soil and restrict its biological benefits in the plant.…”

“…The induction of a new homeostatic balance of C:N:P caused by Si under water deficit conditions also occurs in 30-day pre-sprouted seedlings [ 13 ], and 90-days [ 32 ], 150-days [ 33 ] and 160-days [ 31 ] sugarcane plants. The induction of a new C:N:P homeostasis is not only restricted in sugarcane plants, but has also been observed in forage [ 26 , 27 ], quinoa [ 35 ], wheat [ 36 ], sorghum and sunflower [ 17 , 37 ].…”

Nanosilica modulates C:N:P stoichiometry attenuating phosphorus toxicity more than deficiency in Megathyrsus maximus cultivated in an Oxisol and Entisol

“…Therefore, for the rst time there is a report on the potential of Si to modify C:N:P stoichiometry in forage plants cultivated under excess P, but this depends on the soil used for cultivated, as it stood out more in Entisol, probably due to the greater severity of macronutrient toxicity. Research on the effects of Si on C:N:P stoichiometry in stressed plants [92] , of water de cit in sugarcane [54,93,43] , and of the effect of Si in the forage plant M. maximus are recent [38] .…”

“…A new approach discusses the bene ts of Si for nutrient uptake in plants under limiting conditions [42] and for the modi cation of C:N:P stoichiometry in grasses, attenuating the water de cit [38,43] and nutritional de ciency in forage plants under hydroponic cultivation [44] . This change in C stoichiometry must be related to the incorporation of Si into the cell wall, being metabolized at a low energy cost compared to the synthesis of structural carbon compounds such as lignin [45,46] , and these factors may favor plant growth under stress.…”