Growing in Mixed Stands Increased Leaf Photosynthesis and Physiological Stress Resistance in Moso Bamboo and Mature Chinese Fir Plantations

Abstract

Mixed-stand plantations are not always as beneficial for timber production and carbon sequestration as monoculture plantations. Systematic analyses of mixed-stand forests as potential ideal plantations must consider the physiological-ecological performance of these plantations. This study aimed to determine whether mixed moso bamboo (Phyllostachys pubescens (Pradelle) Mazel ex J. Houz.) and Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.) stands exhibited better physiological-ecological performance than monoculture plantations of these species. We analyzed leaf photosynthesis, chlorophyll fluorescence, antioxidant enzyme activities, chlorophyll content and leaf chemistry in a moso bamboo stand, a Chinese fir stand and a mixed stand with both species. The results showed that both species in the mixed stand exhibited significantly higher leaf net photosynthesis rate (Amax), instantaneous carboxylation efficiency (CUE), chlorophyll content, maximum quantum yield of photosynthesis (Fv/Fm), photochemical quenching coefficient (qP), PSII quantum yield [Y(II)], leaf nitrogen content, and antioxidant enzyme activities than those in the monoculture plantations. However, the non-photochemical quenching (NPQ) in Chinese fir and 2-year-old moso bamboo was significantly lower in the mixed stand than in the monocultures. In addition, the water use efficiency (WUE) of Chinese fir was significantly higher in the mixed stand. The results suggest that the increase in leaf net photosynthetic capacity and the improved growth in the mixed stand could be attributed primarily to the (i) more competitive strategies for soil water use, (ii) stronger antioxidant systems, and (iii) higher leaf total nitrogen and chlorophyll contents in the plants. These findings suggest that mixed growth has beneficial effects on the leaf photosynthesis capacity and physiological resistance of moso bamboo and Chinese fir.

Age effects of Moso bamboo on leaf isoprene emission characteristics

“…The leaf photosynthetic capacity decreased with increasing culm age; however, the isoprene emission rate followed the order of young >old >and mature plants. The effects of culm age on photosynthesis observed in our study are consistent with those of previous studies ( Kleinhenz and Midmore, 2001 ; Peng et al., 2021 ). As expected, young plants had the highest isoprene emission rate because the biosynthesis of isoprene is based on a photosynthetically fixed carbon ( Niinemets et al., 2002 ; Jardine et al., 2014 ; de Souza et al., 2018 ).…”

“…Owing to a lack of secondary development and the blocking of xylem vessels by tyloses, aged culms are particularly susceptible to xylem dysfunction; this can lead to a progressive loss of photosynthates, nutrients, and conductivity for water and, eventually, culm mortality ( Liese and Weiner, 1996 ). Moreover, leaf morphology ( Hu et al., 2021 ) and photosynthesis ( Kleinhenz and Midmore, 2001 ; Peng et al., 2021 ) depend not only on the leaf age but also on the culm age. However, whether culm age affects leaf isoprene emissions is unclear.…”

Modeling of the Potential Geographical Distribution of Three Fritillaria Species Under Climate Change

“…Most of the distribution area, including the center area, of three Fritillaria species received the influence of monsoon from the Indian and Pacific oceans and has sufficient precipitation from May to September. Water was reported to play an essential role in root growth ( Sharma et al, 2021 ), seed dormancy and germination ( Sheppard et al, 2014 ), and leaf growth and photosynthesis ( Peng et al, 2021 ). Water deficiency would activate transcription factors and thus promote the expression of stress-related genes ( Van Beek et al, 2021 ), whereas sufficient water would increase stomatal and leaf area ( Mozo et al, 2021 ) and promote dormancy and germination ( Chritine et al, 2014 ; Sheppard et al, 2014 ).…”

Integrating Physiological Features and Proteomic Analyses Provides New Insights in Blue/Red Light-Treated Moso Bamboo (Phyllostachys edulis)

“…10,11 Moso bamboo efficiently utilizes light energy to synthesize essential organic matter, contributing significantly to its rapid growth. 12 It has been reported that young bamboo shoots will perish within 10 days under complete shading treatment, 13 which highlights the importance of light for the growth of Moso bamboo. Currently, there have been notable advancements in the examination of light regulation in Moso bamboo.…”

“…Presently, research on Moso bamboo predominantly centers on both biotic and abiotic stresses that impact its yield, including factors such as disease infestation, drought, soil salinity, temperature, and high light . Light, as a critical factor, serves not only as an energy source for photosynthesis in plants but also plays a crucial role in regulating the growth and development of plants. , Moso bamboo efficiently utilizes light energy to synthesize essential organic matter, contributing significantly to its rapid growth . It has been reported that young bamboo shoots will perish within 10 days under complete shading treatment, which highlights the importance of light for the growth of Moso bamboo.…”