Physiological Responses in C3 and C4 Turfgrasses under Soil Water Deficit

Abstract

<jats:p>Lawns must be managed increasingly under less frequent or deficit irrigation. Deficit irrigation can reduce gas exchange, carbon assimilation, and physiological function in both warm- (C<jats:sub>4</jats:sub>) and cool- (C<jats:sub>3</jats:sub>) season turfgrasses, yet limited research has compared the physiological response to increasing levels of soil water deficit. The objectives of this greenhouse study were to compare three commonly used transition-zone turfgrasses—bermudagrass [<jats:italic>Cynodon dactylon</jats:italic> (L.) Pers.] (C<jats:sub>4</jats:sub>), buffalograss [<jats:italic>Buchloe dactyloides</jats:italic> (Nutt.) Engelm.] (C<jats:sub>4</jats:sub>), and tall fescue (<jats:italic>Festuca arundinacea</jats:italic> Schreb.) (C<jats:sub>3</jats:sub>)—and their ability to maintain quality and physiological function under water deficit stress. Visual turf quality, normalized difference vegetation index (NDVI), reflective canopy temperature, and gross photosynthesis were evaluated initially near field capacity (FC), and subsequent soil water deficit [48% (moderate) and 33% (severe) of plant-available water] conditions. Bermudagrass and tall fescue had similar quality ratings near FC, although the photosynthetic rate was greater for bermudagrass. Compared with other turfgrasses, bermudagrass maintained greater turf quality, NDVI, and photosynthetic rates further into water deficit stress. Tall fescue quality and photosynthetic rates declined most rapidly in both experiments as a result of the combined heat and drought stress. Buffalograss used less water compared with other species, and maintained consistent turf quality, NDVI, and photosynthetic rates under moderate and severe water deficit. These results support the notion that buffalograss and bermudagrass are better adapted than tall fescue at maintaining functional and ecosystem services with shallow soil depths in landscape situations under imposed summertime water restrictions.</jats:p>

Effect of Plants Morphological Parameters on Plant-Microbial Fuel Cell Efficiency

“…The increase of both biomass production and CO 2 fixation with light intensity and CO 2 concentration in C4 is faster than that in C3, which reflected more efficient use of light and CO 2 in C4 plant. C4 plants approximately have 50% higher photosynthesis efficiency than those of C3 plants [32,40,41]. Apparently, the C4 pathway of C. hirta sedge is another advantage of PMFC based on it, which contributes to its effectiveness.…”

Evaluation of newly established buffalograss for tolerance to glyphosate

“…Buffalograss treated with 2.0 lb N 1,000 sq ft –1 exhibited acceptable turf quality while reducing clipping yields compared with treatment with 4.0 lb N 1,000 sq ft –1 (Frank et al., 2004). Greenhouse and field trials have demonstrated that buffalograss withstands deficit irrigation with minimal reduction in turf quality, in comparison to other common warm‐ and cool‐season grasses (Culpepper et al., 2019; Qian & Engelke, 1999). Despite its resilience in low‐input management, buffalograss is still susceptible to encroachment by weeds that can reduce aesthetics and traffic tolerance (Brosnan et al., 2014).…”