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Elevation distribution of fine root biomass and soil organic carbon storage of mature Chinese fir (Cunninghamia lanceolata) plantations in East China

100%

Wang Q., Teng Z., Wang J., Xie X., Xu X.

Polish Journal of Ecology

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2020

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tom 68

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nr 1

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Biomass partition and carbon storage of Cunninghamia lanceolata chronosequence plantations in Dabie Mountains in East China

86%

Xie X., Cui J., Shi W., Liu X., Tao X., Wang Q., Xu X. N.

Dendrobiology

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2016

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tom 76

The quantification of biomass carbon pools is important for understanding carbon cycling in forest ecosystems. This study was designed to reveal the effects of stand age on biomass partitioning and carbon storage of Chinese fir plantation stands in Dabie Mountains of Anhui, East China. A total of six even-aged Chinese fir plantation stands along an age-sequence from 10 to 50 years were selected. To quantify the biomass of different tree components, 18 trees with diameter at breast height (D1.3) from 6.5 to 35.2 cm were harvested from the different aged stands. Biomasses of understory vegetation, forest floor and standing dead trees were also investigated. Total biomass carbon storages ranged from 57.6 to 211.4 Mg ha–1 in the different aged stands. Tree layer comprised from 93.7% to 96.4% of the total biomass C pools in the different aged stands. The C pools of the necromass were from 1.8 to 6.2 Mg ha–1. Stand age had a significant effect on tree biomass partitioning, with an increase in proportion of root biomass. The root/shoot ratios were from 0.187 to 0.312, which was significantly positively correlated to stand age. The existing plantation stands are still developing and have somewhat high rate of biomass and carbon accumulations beyond the normal rotation period (usually 25–30 years) even over an age of 50 years. Appropriate prolongation of the rotation period of Chinese fir plantation will be effective in maintaining long-term productivity and providing large carbon sink. The measurements provide valuable data for modelling productivity of Chinese fir plantation forest.

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Transcriptomic responses in Neolitsea sericea leaves under acute drought stress

86%

Wang Y., Zhao L., Xie X., Huang J., Li D., Chen W., Zhu A.

Acta Physiologiae Plantarum

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2018

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tom 40

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nr 02

Neolitsea sericea is acclimated to arid islands, but few studies have examined its responses to water stress. To look into the defending responses that assist N. sericea seedlings to survive drought, physiological and transcriptomic analysis of leaves was conducted after drought was induced. Over 17,768,244 reads for each sample were generated, totalling over 4400 million base pairs (bp). Among 129,239 unigenes that were assembly yielded with an average length of 816 bp, 51,137 of them (39.6%) were annotated successfully. Under severe drought, physiological inhibition was strengthened and abscisic acid content was significantly upregulated. The responses were strongly accompanied by transcriptional regulation of genes participating in stress perception, protective signalling, hormone metabolism, transcription factors, abiotic stress, transport, and degradation. In total, 61, 65, and 67 differentially expressed genes were identified after 12, 24, and 72 h exposure to severe drought stress, respectively. Gene Ontology and MapMan functional enrichment analysis revealed that the most upregulated genes were involved in protein transport, the regulation of transcription, and miscellaneous enzyme families. In addition, genes that encode glycosyl transferase and UDP-glycosyltransferases may modulate the drought-stress responses of N. sericea. Multiple hormones were active in N. sericea leaves during drought stress, including those associated with auxins, abscisic acid, brassinosteroid, and cytokinins. Transcription factors, including AtbHLH112, AtCOL4, AtZFP3, AtCIR1, and AtCCA1, may participate in ABA signal transduction in drought-treated N. sericea. The present study elucidates how N. sericea make transcriptomic responses to drought stress, helping to reveal the molecular mechanisms connected to drought adaptation.

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Downregulation of the lycopene ε-cyclase gene confers tolerance to salt and drought stress in Nicotiana tabacum

52%

Shi J., Liu P., Xia Y., Wei P., Li W., Zhang W., Chen X., Cao P., Xu Y., Jin L., Li F., Luo Z., Wei C., Zhang J., Xie X., Qu L., Yang J., Lin F., Wang R.

Acta Physiologiae Plantarum

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2015

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tom 37

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nr 10

Lycopene ε-cyclase (ε-LCY) functions at a branch point of the carotenoid biosynthesis pathway and modulates the ratio of lutein to the β-carotenoids. RNA interference (RNAi) and overexpression (OE) of Ntε-LCY were used to evaluate the physiological roles of ε-LCY in Nicotiana tobacum. In leaves, strong accumulation of β branch carotenoids and high expression of carotenoid biosynthesis genes resulted from suppression of Ntε-LCY expression. RNAi plants showed enhanced salt and drought tolerance, while overexpression of the Ntε-LCY gene weakened tolerance to salt and drought stress, as compared to control. Further analysis revealed that RNAi plants exhibited less water loss and had lower reactive oxygen species levels than did WT plants after both the salt and drought treatments. Further, higher levels of ABA accumulated in the RNAi lines than in the WT lines under stress conditions. These results suggest that reduced Ntε-LCY expression can improve drought and salinity tolerance in Nicotiana tabacum by enhancing their ROS scavenging ability.

Ograniczanie wyników

Elevation distribution of fine root biomass and soil organic carbon storage of mature Chinese fir (Cunninghamia lanceolata) plantations in East China

Biomass partition and carbon storage of Cunninghamia lanceolata chronosequence plantations in Dabie Mountains in East China

Transcriptomic responses in Neolitsea sericea leaves under acute drought stress

Downregulation of the lycopene ε-cyclase gene confers tolerance to salt and drought stress in Nicotiana tabacum