Elevated CO2 reduces the drought effect on nitrogen metabolism in barley plants during drought and subsequent recovery

Abstract2-(3,4-Dichlorophenoxy) triethylamine (DCPTA) regulates many aspects of plant development; however, its effects on soil drought tolerance are unknown. We pre-treated maize (Zea mays L.) by foliar application of DCPTA and subsequently exposed the plants to soil drought and rewatering conditions during the pre-female inflorescence emergence stage. Exogenous DCPTA significantly alleviated drought-induced decreases in maize yield, shoot and root relative growth rate (RGR), leaf relative water content (RLWC), net photosynthetic rate (Pn), stomatal conductance (Gs) and transpiration rate (Tr), nitrate (NO3−), nitrite (NO2−), and soluble protein contents, and nitrate reductase (NR), nitrite reductase (NiR), isocitrate dehydrogenase (ICDH), alanine aminotransferase (AlaAT) and aspartate aminotransferase (AspAT) activities; increases in the intercellular CO2 concentration (Ci), the ammonium (NH4+) and free amino acid contents, and the glutamate dehydrogenase (GDH) and protease activities. Simultaneously, exogenous DCPTA improved the spatial and temporal distribution of roots and increased the root hydraulic conductivity (Lp), flow rate of root-bleeding sap and NO3− delivery rates. Moreover, Exogenous DCPTA protected the chloroplast structure from drought injury. Taken together, our results suggest that exogenous DCPTA mitigates the repressive effects of drought on N metabolism and subsequently enhances drought tolerance during the pre-female inflorescence emergence stage of maize.HighlightsThis is the first article that explores the effects of DCPTA on nitrogen metabolism and the first article that explores the effects of DCPTA on crops under soil drought conditions.

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Elevated CO2 alters tissue balance of nitrogen metabolism and downregulates nitrogen assimilation and signalling gene expression in wheat seedlings receiving high nitrate supply

PROTOPLASMA ◽

10.1007/s00709-020-01564-3 ◽

2020 ◽

Vol 258 (1) ◽

pp. 219-233

Author(s):

Sandeep B. Adavi ◽

Lekshmy Sathee

Keyword(s):

Gene Expression ◽

Nitrogen Metabolism ◽

Elevated Co2 ◽

Nitrogen Assimilation ◽

Wheat Seedlings ◽

Nitrate Supply

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Photosynthetic carbon and nitrogen metabolism and the relationship between their metabolites and lipid peroxidation in dwarf bamboo (Fargesia rufa Yi) during drought and subsequent recovery

Trees ◽

10.1007/s00468-015-1241-0 ◽

2015 ◽

Vol 29 (6) ◽

pp. 1633-1647 ◽

Cited By ~ 8

Author(s):

Chenggang Liu ◽

Yanjie Wang ◽

Kaiwen Pan ◽

Yanqiang Jin ◽

Jin Liang ◽

...

Keyword(s):

Lipid Peroxidation ◽

Nitrogen Metabolism ◽

Dwarf Bamboo ◽

Subsequent Recovery ◽

Carbon And Nitrogen ◽

Photosynthetic Carbon ◽

Carbon And Nitrogen Metabolism ◽

The Relationship

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Response of Nitrogen Metabolism in Masson Pine Needles to Elevated CO2

Forests ◽

10.3390/f11040390 ◽

2020 ◽

Vol 11 (4) ◽

pp. 390

Author(s):

Fan Wu ◽

Xiaobo Sun ◽

Xingfeng Hu ◽

Bingzhang Zou ◽

Nengqing Lin ◽

...

Keyword(s):

Gene Expression ◽

Nitrogen Metabolism ◽

Elevated Co2 ◽

Enzyme Activities ◽

Glutamate Synthase ◽

Pinus Massoniana ◽

Pine Needles ◽

Future Research ◽

Nitrate Content ◽

Masson Pine

To explore the response of nitrogen metabolism in Masson pine (Pinus massoniana) to high CO2 concentrations, needles from one-year-old seedlings were used as materials to detect key enzyme activities, gene expression and different forms of nitrogen metabolites after CO2 stress for different durations (0 h, 6 h, 12 h, 24 h). The results show that elevated CO2 affected the efficiency of nitrogen metabolism in Masson pine needles, inhibiting the expression of key genes involved in nitrogen metabolism, including glutamate synthase (GOGAT), nitrite reductase (NiR), glutamine synthase (GS), nitrate reductase (NR) and glutamate dehydrogenase (GDH), and decreasing the activities of GOGAT, NiR, and GS. The decrease in enzyme activities and gene expression caused a decrease in different forms of nitrogen metabolites, including total nitrogen, ammonium, nitrite and specific amino acids. With prolonged stress, the nitrate content increased first and then decreased. In this study, the response pattern of nitrogen metabolism to CO2 stress in Masson pine needles was described, which may aid future research on nitrogen utilization in Masson pine.

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Photosynthetic Responses of Canola and Wheat to Elevated Levels of CO2, O3 and Water Deficit in Open-Top Chambers

Plants ◽

10.3390/plants8060171 ◽

2019 ◽

Vol 8 (6) ◽

pp. 171 ◽

Cited By ~ 1

Author(s):

Bheki G. Maliba ◽

Prabhu M. Inbaraj ◽

Jacques M. Berner

Keyword(s):

Water Deficit ◽

Elevated Co2 ◽

Photosynthetic Efficiency ◽

Jip Test ◽

Drought Effect ◽

Open Top Chambers ◽

Non Invasive ◽

Elevated O3 ◽

Photosynthetic Responses ◽

Chlorophyll A Fluorescence Transients

The effects of elevated CO2 (700 ppm) and O3 (80 ppb) alone and in combination on the photosynthetic efficiency of canola and wheat plants were investigated in open-top chambers (OTCs). The plants were fumigated for four weeks under well-watered and water-stressed (water deficit) conditions. The fast chlorophyll a fluorescence transients were measured after 2 and 4 weeks of fumigation, as well as in control plants, and analyzed by the JIP-test, which is a non-destructive, non-invasive, informative, very fast and inexpensive technique used to evaluate the changes in photosynthetic efficiency. Biomass measurements were taken only after 4 weeks of fumigation. The performance index (PItotal), an overall parameter calculated from the JIP-test formulae, was reduced by elevated CO2 and O3 under well-watered conditions. In the absence of any other treatment, water stress caused a decrease of the PItotal, and it was partly eliminated by fumigation with elevated CO2 and CO2 + O3. This finding was also supported by the biomass results, which revealed a higher biomass under elevated CO2 and CO2 + O3. The decrease in biomass induced by elevated O3 was likely caused by the decline of photosynthetic efficiency. Our findings suggest that elevated CO2 reduces the drought effect both in the absence and presence of O3 in canola and wheat plants. The study also indicates that elevated O3 would pose a threat in future to agricultural crops.

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