Stomatal development and associated photosynthetic performance of capsicum in response to differential light availabilities

Abstract

The mechanisms of capsicum growth in response to differential light availabilities are still not well elucidated. Hereby, we analyzed differential light availabilities on the relationship between stomatal characters and leaf growth, as well as photosynthetic performance. We used either 450-500 μmol m -2 s -1 as high light (HL) or 80-100 μmol m -2 s -1 as low light (LL) as treatments for two different cultivars. Our results showed that the stomatal density (SD) and stomatal index (SI) increased along with the leaf area expansion until the peak of the correlation curve, and then decreased. SD and SI were lower under the LL condition after three days of leaf expansion. For both cultivars, downregulation of photosynthesis and electron transport components was observed in LL-grown plants as indicated by lower light-and CO 2 -saturated photosynthetic rate (P max and RuBP max ), quantum efficiency of photosystem II (PSII) photochemistry (Φ PSII ), electron transport rate (ETR) and photochemical quenching of fluorescence (q p ). The observed inhibition of the photosynthesis could be explained by the decrease of SD, SI, Rubisco content and by the changes of the chloroplast. The low light resulted in lower total biomass, root/shoot ratio, and the thickness of the leaf decreased. However, the specific leaf area (SLA) and the content of leaf pigments were higher in LL-treatment. Variations in the photosynthetic characteristics of capsicum grown under different light conditions reflected the physiological adaptations to the changing light environments.

Effects of Substrate Salinity and Nutrient Levels on Physiological Response, Yield, and Fruit Quality of Habanero Pepper

“…1). Control plants had a photosynthetic efficiency comparable to values obtained in previous studies on C. annuum 'Zhongjiao' and 'Niujiao' (Fu et al, 2010). The light-saturated photosynthetic rate was reduced significantly at low N and 7 dS · m -1 salinity levels to 47% and 64%, respectively, of the observed control rate (Table 2; Fig.…”

SlERF36, an EAR-motif-containing ERF gene from tomato, alters stomatal density and modulates photosynthesis and growth

“…This in turn severely limits the photosynthetic rate as evident from the 30–50% decrease in CO 2 assimilation in transgenic plants. Such an effect of reduced stomatal density and conductance on CO 2 uptake, photosynthesis, and productivity has also been reported in several previous studies in various plants (Freeland, 1948; Heichel, 1971; Fu et al , 2010). Conversely, stomatal density is markedly affected by the environment and hence an effect of reduced photosynthesis on stomatal density reduction cannot be ruled out.…”

Pepper Photosynthesis, Stomatal Conductance, Transpiration, and Water Use Efficiency Differ with Variety, Indigenous Habitat, and Species of Origin

“…However, our values were generally higher than those reported by Borisev et al (2012) who also reported that the WUE of indoorgrown C. annuum variety (nine) varied less than that of field-grown plants (3.2-3.5 and 2.3-3.9, respectively). The WUE of Capsicum is reportedly impacted by irradiance; WUE was higher when plants were grown under high irradiance (400 mmol • m -2 • s -1 ; 2.2) compared to low irradiance (200 mmol • m -2 • s -1 ; 1.8) (Fu et al, 2010). However, irradiance in our study was 1000 mmol • m -2 • s -1 ; therefore, it would be considered high.…”