scholarly journals Root Response of Moso Bamboo (Phyllostachys edulis (Carrière) J. Houz.) Seedlings to Drought with Different Intensities and Durations

Forests ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 50
Author(s):  
Zhenya Yang ◽  
Yonghui Cao ◽  
Jiancheng Zhao ◽  
Benzhi Zhou ◽  
Xiaogai Ge ◽  
...  
Keyword(s):  
Drought Stress ◽  
Root Architecture ◽  
Specific Root Length ◽  
Dry Weight ◽  
Adaptation Strategies ◽  
Moso Bamboo ◽  
Severe Drought ◽  
Phyllostachys Edulis ◽  
Root Branching ◽  
Moderate Drought

The root of Moso bamboo (Phyllostachys edulis (Carrière) J. Houz.) develops extremely rapidly at seedling phase and is highly sensitive to water content in soil, but its response patterns and adaptation strategies of its root to drought are little known. The aim of this study was to investigate the response of root morphology and architecture of Moso bamboo to drought at seedling phase and then to explore the drought adaptation strategies of its root. One-year-old potted seedlings of Moso bamboo were planted under three drought treatments (control, moderate drought and severe drought) for three months. Seedling growth, specific root length (SRL), root architecture (fractal dimension (FD), root branching angle (RBA) and root topological index (TI)) and non-structural carbohydrate (NSC) concentrations in roots were measured every month. The results are as follows: (i) The dry weight of root and shoot decreased significantly under drought stress. (ii) The SRL decreased under drought stress in the early duration (the first month), and then increased in the late duration (the third month). Both FD and RBA decreased, while TI and the concentrations of NSCs increased under drought stress. (iii) The NSC concentrations were positively correlated with SRL and TI, but exhibited an inverse relationship to FD and RBA. Our results indicated that Moso bamboo seedlings formed a “steeper, simpler, expensive (low SRL and high TI)” root architecture to adapt to a short-term drought (one month), and formed a “cheaper (high SRL)” root to adapt to a long-term drought (three months). Increase of NSC concentrations supported the root architecture plasticity to some extent.

scholarly journals Effects of root phenotypic changes on the deep rooting of Populus euphratica seedlings under drought stresses

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6513 ◽  
Author(s):  
Zi-qi Ye ◽  
Jian-ming Wang ◽  
Wen-juan Wang ◽  
Tian-han Zhang ◽  
Jing-wen Li
Keyword(s):  
Drought Stress ◽  
Root Architecture ◽  
Mass Fraction ◽  
Populus Euphratica ◽  
Severe Drought ◽  
Root Depth ◽  
Phenotypic Changes ◽  
Positive Effects ◽  
Drought Conditions ◽  
Moderate Drought

Background Deep roots are critical for the survival of Populus euphratica seedlings on the floodplains of arid regions where they easily suffer drought stress. Drought typically suppresses root growth, but P. euphratica seedlings can adjust phenotypically in terms of root-shoot allocation and root architecture and morphology, thus promoting deep rooting. However, the root phenotypic changes undertaken by P. euphratica seedlings as a deep rooting strategy under drought conditions remain unknown. Methods We quantified deep rooting capacity by the relative root depth (RRD), which represents the ratio of taproot length to plant biomass and is controlled by root mass fraction (RMF), taproot mass fraction (TRMF), and specific taproot length (STRL). We recorded phenotypic changes in one-year-old P. euphratica seedlings under control, moderate and severe drought stress treatments and assessed the effects of RMF, TRMF, and STRL on RRD. Results Drought significantly decreased absolute root depth but substantially increased RRD via exerting positive effects on TRMF, RMF, and STRL. Under moderate drought, TRMF contributed 55%, RMF 27%, and STRL 18% to RRD variation. Under severe drought, the contribution of RMF to RRD variation increased to 37%, which was similar to the 41% for TRMF. The contribution of STRL slightly increased to 22%. Conclusion These results suggest that the adjustments in root architecture and root-shoot allocation were predominantly responsible for deep rooting in P. euphratica seedlings under drought conditions, while morphological changes played a minor role. Moreover, P. euphratica seedlings rely mostly on adjusting their root architecture to maintain root depth under moderate drought conditions, whereas root-shoot allocation responds more strongly under severe drought conditions, to the point where it plays a role as important as root architecture does on deep rooting.

scholarly journals Role of Suillus placidus in Improving the Drought Tolerance of Masson Pine (Pinus massoniana Lamb.) Seedlings

Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 332
Author(s):  
Min Li ◽  
Haoyun Wang ◽  
Xizhou Zhao ◽  
Zhongke Lu ◽  
Xueguang Sun ◽  
...  
Keyword(s):  
Drought Stress ◽  
Defense Mechanism ◽  
Southern China ◽  
Dry Weight ◽  
Pinus Massoniana ◽  
Photosynthetic Performance ◽  
Ectomycorrhizal Fungus ◽  
Severe Drought ◽  
Masson Pine ◽  
Pine Seedlings

Masson pine is an important afforestation species in southern China, where seasonal drought is common. The present study focused on the effects of Suillus placidus, an ectomycorrhizal fungus, inoculation on the growth and physiological and biochemical performance of masson pine seedlings under four different watering treatments (well-watered, mild drought, moderate drought, and severe drought) to evaluate the symbiotic relationship between S. placidus and masson pine seedlings. Ectomycorrhizal-inoculated (ECM) and non-inoculated (NM) seedlings were grown in pots and maintained for 60 days using the weighing method. Results showed that seedlings’ growth, dry weight, RWC, chlorophyll content, PSII efficiency, and photosynthesis decreased as drought stress intensified in both ECM and NM plants. This suggests that drought stress significantly limits the growth and photosynthetic performance of masson pine seedlings. Nevertheless, increased An/gs and proline contents in both NM and ECM prevented oxidative damage caused by drought stress. In addition, increased peroxidase (POD) activity is an essential defense mechanism of ECM seedling under drought stress. Compared with NM, ECM seedlings showed faster growth, higher RWC, and photosynthetic performance, and lower lipid peroxidation in cell membranes under drought stress, as indicated by higher POD activity and lower proline and malondialdehyde (MDA). Our experiment found that S. placidus inoculation can enhance the drought resistance of masson pine seedlings by increasing antioxidant enzyme activity, water use efficiency, and proline content, thereby enhancing growth under water-deficiency conditions. S. placidus can be used to cultivate high-quality seedlings and improve their survival in regions that experience seasonal droughts.

Mapping QTLs for yield components and chlorophyll a fluorescence parameters in wheat under three levels of water availability

2011 ◽  
Vol 9 (2) ◽  
pp. 291-295 ◽  
Author(s):  
Ilona Czyczyło-Mysza ◽  
Izabela Marcińska ◽  
Edyta Skrzypek ◽  
Małgorzata Chrupek ◽  
Stanisław Grzesiak ◽  
...  
Keyword(s):  
Drought Stress ◽  
Chlorophyll A ◽  
Chlorophyll A Fluorescence ◽  
Wheat Yield ◽  
Dry Weight ◽  
Interval Mapping ◽  
Main Stem ◽  
Severe Drought ◽  
Single Marker Analysis ◽  
Fluorescence Parameters

Drought is one of the major factors limiting wheat yield in many developing countries worldwide. Parameters of chlorophyll a fluorescence kinetics under drought stress conditions have been used to characterize dehydration tolerance in wheat. In the present study, a set of 94 doubled haploid lines obtained from Chinese Spring × SQ1 (CSDH), mapped with 450 markers, was evaluated for yield (grain dry weight/main stem ear), number of grains/main stem ear (NG) and chlorophyll a fluorescence parameters (FC) under moderate and severe drought stress, and compared with results for well-watered plants. quantitative trait loci (QTLs) were identified using Windows QTLCartographer version 2.5 software and the results were analysed using single-marker analysis (SMA) and composite interval mapping (CIM). Analysis using SMA and CIM showed mostly similar QTLs for all traits, though more QTLs were identified by SMA than by CIM. The genetic control of yield, NG and FC varied considerably between drought-stressed and non-stressed plants. Although no major QTL co-locations were found for yield and FC using CIM, the co-location of QTLs for NG, yield and Fv/Fm in drought-stressed plants was observed on chromosome 5A using SMA.

scholarly journals Enhancement of drought tolerance in diverse Vicia faba cultivars by inoculation with plant growth-promoting rhizobacteria under newly reclaimed soil conditions

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Elsayed Mansour ◽  
Hany A. M. Mahgoub ◽  
Samir A. Mahgoub ◽  
El-Sayed E. A. El-Sobky ◽  
Mohamed I. Abdul-Hamid ◽  
...  
Keyword(s):  
Drought Stress ◽  
Drought Tolerance ◽  
Plant Growth ◽  
Plant Growth Promoting Rhizobacteria ◽  
Severe Drought ◽  
Drought Conditions ◽  
Moderate Drought ◽  
Plant Growth Promoting ◽  
Growth Promoting ◽  
Effects Of Drought

AbstractWater deficit has devastating impacts on legume production, particularly with the current abrupt climate changes in arid environments. The application of plant growth-promoting rhizobacteria (PGPR) is an effective approach for producing natural nitrogen and attenuating the detrimental effects of drought stress. This study investigated the influence of inoculation with the PGPR Rhizobium leguminosarum biovar viciae (USDA 2435) and Pseudomonas putida (RA MTCC5279) solely or in combination on the physio-biochemical and agronomic traits of five diverse Vicia faba cultivars under well-watered (100% crop evapotranspiration [ETc]), moderate drought (75% ETc), and severe drought (50% ETc) conditions in newly reclaimed poor-fertility sandy soil. Drought stress substantially reduced the expression of photosynthetic pigments and water relation parameters. In contrast, antioxidant enzyme activities and osmoprotectants were considerably increased in plants under drought stress compared with those in well-watered plants. These adverse effects of drought stress reduced crop water productivity (CWP) and seed yield‐related traits. However, the application of PGPR, particularly a consortium of both strains, improved these parameters and increased seed yield and CWP. The evaluated cultivars displayed varied tolerance to drought stress: Giza-843 and Giza-716 had the highest tolerance under well-watered and moderate drought conditions, whereas Giza-843 and Sakha-4 were more tolerant under severe drought conditions. Thus, co-inoculation of drought-tolerant cultivars with R. leguminosarum and P. putida enhanced their tolerance and increased their yield and CWP under water-deficit stress conditions. This study showed for the first time that the combined use of R. leguminosarum and P. putida is a promising and ecofriendly strategy for increasing drought tolerance in legume crops.

Phedimus Aizoon L. Responds to Drought Stress: Growth, Physiological Changes and Mechanism of Drought Resistance

2020 ◽  
Author(s):  
Yuhang Liu ◽  
Zhongqun He ◽  
Yongdong Xie ◽  
Lihong Su ◽  
Ruijie Zhang ◽  
...  
Keyword(s):  
Drought Stress ◽  
Drought Resistance ◽  
Soluble Sugar ◽  
Severe Drought ◽  
Physiological Changes ◽  
Moderate Drought ◽  
Negative Effect ◽  
Mda Content ◽  
Maximum Water ◽  
Mild Drought

Abstract A pot experiment was conducted to investigate the growth, physiological changes and mechanism of drought resistance of Phedimus aizoon L. under different levels of water content .CK: 75% ~ 80% of the MWHC (maximum water holding capacity), Mild drought: 55% ~ 60%, Moderate drought: 40% ~ 45%, Severe drought: 20% ~ 25%.We observed that the plants grew normally in the first two treatments, even the mild drought promoted the growth of the roots. In the last two treatments, drought stress had a significant negative effect on plant growth, at the same time, Phedimus aizoon L. also made positive physiological response to cope with the drought: The aboveground part of the plant (leaf, plant height, stem diameter) was smaller, the waxy layer of the leaves was thickened, the stomata of the leaves were closed during the day, and only a few stomata were opened at night, which proved that the dark reaction cycle metabolism mode of the plant was transformed from C3 cycle to CAM pathway. The activity of antioxidant enzymes (SOD, POD and CAT) was continuously increased to alleviate the damage caused by drought. To ensure the relative stability of osmotic potential, the contents of osmoregulation substances such as proline, soluble sugar, soluble protein and trehalose increased correspondingly. But plants have limited regulatory power, with aggravation of drought stress degree and extension of stress time, the MDA content and electrolyte leakage of leaves increased continuously. Observed under electron microscope,the morphology of chloroplast and mitochondria changed and the membrane structure was destroyed. The plant's photosynthetic and respiratory mechanisms are destroyed and the plant gradually die.

scholarly journals The Arabidopsis expansin gene (AtEXPA18) is capable to ameliorate drought stress tolerance in transgenic tobacco plants

2021 ◽  
Author(s):  
Alireza Abbasi ◽  
Meysam Malekpour ◽  
Sajjad Sobhanverdi
Keyword(s):  
Drought Stress ◽  
Transgenic Plants ◽  
Transgenic Tobacco ◽  
Dry Weight ◽  
Conventional Polymerase Chain Reaction ◽  
Specific Gene ◽  
Severe Drought ◽  
Transgenic Tobacco Plants ◽  
Tobacco Plants ◽  
Reverse Transcription Pcr

Abstract Expansins are cell wall proteins that, due to changes in pH, causing the expansion of the cell walls. In this study, a previously gene construct designed based on a root-specific gene, AtEXPA18, was utilized to assess its potential roles on different morphological, physiological, and cellular levels of generated transgenic tobacco plants in response to moderate and severe drought stress. AtEXPA18 gene was successfully transferred to the tobacco plants through an agrobacterium-mediate transformation system. Upon obtaining the second generation, tobacco transgenic plants were confirmed by conventional polymerase chain reaction (PCR) technique alongside reverse transcription PCR (RT-PCR) using specific primers. Under drought stress, the transgenic lines showed remarkable growth and significantly improved based on morphological traits such as height and stem diameter, leaf area, leaf number, root dry weight, and Abscisic acid (ABA) levels of leaves compared control plants. As a result, the Cytokinin content of transgenic plants has increased under severe stress levels. Notably, the area's expansion for abaxial epidermal cells under the microscope confirmed in transgene cells compared with the -transgene cells. These results, altogether, could support the AtEXPA18 gene implication in cell expansion and improving tolerance capacity of transgenic crops under drought stress.

scholarly journals Genetic Parameters and QTLs for Total Phenolic Content and Yield of Wheat Mapping Population of CSDH Lines under Drought Stress

2019 ◽  
Vol 20 (23) ◽  
pp. 6064 ◽  
Author(s):  
Czyczyło-Mysza ◽  
Cyganek ◽  
Dziurka ◽  
Quarrie ◽  
Skrzypek ◽  
...  
Keyword(s):  
Drought Stress ◽  
Total Phenolic Content ◽  
Genetic Parameters ◽  
Phenolic Content ◽  
Dry Weight ◽  
Total Phenolic ◽  
Doubled Haploid Population ◽  
Severe Drought ◽  
Gene Effects ◽  
Significant Additive Effect

A doubled haploid population of 94 lines from the Chinese Spring × SQ1 wheat cross (CSDH) was used to evaluate additive and epistatic gene action effects on total phenolic content, grain yield of the main stem, grain number per plant, thousand grain weight, and dry weight per plant at harvest based on phenotypic and genotypic observations of CSDH lines. These traits were evaluated under moderate and severe drought stress and compared with well-watered plants. Plants were grown in pots in an open-sided greenhouse. Genetic parameters, such as additive and epistatic effects, affecting total phenolic content, were estimated for eight year-by-drought combinations. Twenty-one markers showed a significant additive effect on total phenolic content in all eight year-by-drought combinations. These markers were located on chromosomes: 1A, 1B, 2A, 2B, 2D, 3A, 3B, 3D, 4A, and 4D. A region on 4AL with a stable QTL controlling the phenolic content, confirmed by various statistical methods is particularly noteworthy. In all years and treatments, three markers significantly linked to QTLs have been identified for both phenols and yield. Thirteen markers were coincident with candidate genes. Our results indicated the importance of both additive and epistatic gene effects on total phenolic content in eight year-by-drought combinations.

PeSNAC-1 a NAC transcription factor from moso bamboo (Phyllostachys edulis) confers tolerance to salinity and drought stress in transgenic rice

2020 ◽  
Vol 40 (12) ◽  
pp. 1792-1806
Author(s):  
Dan Hou ◽  
Zhongyu Zhao ◽  
Qiutao Hu ◽  
Ling Li ◽  
Naresh Vasupalli ◽  
...  
Keyword(s):  
Drought Stress ◽  
Transgenic Rice ◽  
Interaction Analysis ◽  
Water Shortage ◽  
Moso Bamboo ◽  
Wild Type ◽  
Phyllostachys Edulis ◽  
Functional Roles ◽  
Drought And Salt Stress ◽  
Physiological Indexes

Abstract NAC (NAM, AFAT and CUC) proteins play necessary roles in plant response to environmental stresses. However, the functional roles of NAC genes in moso bamboo (Phyllostachys edulis), an essential economic perennial woody bamboo species, are not well documented. In this study, we retrieved 152 PeNAC genes from the moso bamboo V2 genome, and PeSNAC-1 was isolated and functionally characterized. PeSNAC-1 was localized in the nucleus and had no transactivation activity in yeast. PeSNAC-1 extremely expressed in rhizome and young roots (0.1 and 0.5 cm) and was significantly induced by drought and salt treatments but repressed by abscisic acid (ABA), methyl jasmonate and high temperature (42 °C) in moso bamboo. Under water shortage and salinity conditions, survival ratios, Fv/Fm values, physiological indexes such as activities of superoxide dismutase, peroxidase and catalase and contents of malondialdehyde, H2O2 and proline were significantly higher in transgenic rice than the wild type, which suggests enhanced tolerance to drought and salt stress in PeSANC-1 overexpressed plants. Transcript levels of Na+/H+ antiporter and Na+ transporter genes (OsSOS1, OsNHX1 and OsHKT1;5), ABA signaling and biosynthesis genes (OsABI2, OsRAB16, OsPP2C68, OsLEA3-1, OsLEA3, OsNCED3, OsNCED4 and OsNCED5) and ABA-independent genes (OsDREB1A, OsDREB1B and OsDREB2A) were substantially higher in transgenic as compared with the wild type. Moreover, protein interaction analysis revealed that PeSNAC-1 could interact with stress responsive PeSNAC-2/4 and PeNAP-1/4/5 in both yeast and plant cells, which indicates a synergistic effect of those proteins in regulating the moso bamboo stress response. Our data demonstrate that PeSNAC-1 likely improved salt and drought stress tolerance via modulating gene regulation in both ABA-dependent and independent signaling pathways in transgenic rice. In addition, PeSNAC-1 functions as an important positive stress regulator in moso bamboo, participating in PeSNAC-1 and PeSNAC-2/4 or PeSNAC-1 and PeNAP-1/4/5 interaction networks.

Leaf morphology, photochemistry and water status changes in resprouting Quercus ilex during drought

2005 ◽  
Vol 32 (2) ◽  
pp. 117 ◽  
Author(s):  
Karen Peña-Rojas ◽  
Xavier Aranda ◽  
Richard Joffre ◽  
Isabel Fleck
Keyword(s):  
Drought Stress ◽  
Quercus Ilex ◽  
Structural Characteristics ◽  
Water Status ◽  
Stomatal Closure ◽  
Severe Drought ◽  
Clear Cut ◽  
Leaf Mass Area ◽  
Relative Water ◽  
Moderate Drought

Functional and morphological (structural) characteristics of Quercus ilex L. leaves under drought stress were studied in the forest and in a nursery. We compared undisturbed individuals (controls) with resprouts emerging after clear-cut or excision. When soil water availability was high, gas-exchange was similar in resprouts and controls, despite higher midday leaf water potential, midday leaf hydration and relative water content (RWC). In moderate drought, stomatal closure was found to limit photosynthesis in controls, and in severe drought non-stomatal limitations of photosynthesis were also greater than in resprouts. Leaf structure and chemical composition changed under drought stress. Leaves tended to be smaller in controls with increasing drought, and resprouts had larger leaves and lower leaf mass area (LMA). The relationship between nitrogen (N) content and LMA implied lower N investment in photosynthetic components in controls, which could be responsible for their increased non-stomatal limitation of photosynthesis. Changes were more apparent in leaf density (D) and thickness (T), components of LMA. Decreases in D were related to reductions in cell wall components: hemicellulose, cellulose and lignin. In resprouts, reduced D and leaf T accounted for the higher mesophyll conductance (gmes) to CO2 measured.

scholarly journals The Effect of Potassium Addition on Oil Palm (Elaeis guineensis Jacq.) Roots Anatomic Properties under Drought Stress

2020 ◽  
Vol 35 (1) ◽  
pp. 54
Author(s):  
Wiski Irawan ◽  
Eka Tarwaca Susila Putra
Keyword(s):  
Drought Stress ◽  
Oil Palm ◽  
Elaeis Guineensis ◽  
Block Design ◽  
Field Capacity ◽  
Limiting Factors ◽  
Severe Drought ◽  
Cell Width ◽  
K Fertilizer ◽  
Moderate Drought

The availability of water is one of the main limiting factors for oil palm growth and production. Potassium (K) is an essential nutrient for plants because of its role in controlling metabolic and physiological activities. This study aimed to examine the effect of different K fertilizer doses on root anatomic properties under drought stress. The experiment was arranged in factorial Randomized Complete Block Design (RCBD) with two factors. The first factor was drought stress, consisting of three levels of fractions of transpirable soil water (FTSW) (FTSW 1 (control: field capacity); FTSW 0.35 (moderate drought); FTSW 0.15 (severe drought)) and the second factor was K dose (sourced from KCl), consisting of five levels (K0: 0%; K1: 50%; K2: 100%; K3: 150%; K4: 200%). The results showed that there was an interaction between the addition of K doses and the tolerance level of oil palm plants to drought stress. The addition of 100% K gave higher results in the parameters of xylem diameter, phloem diameter and cortex cell width compared to the plants without K. The results disclosed that 200% K application on moderate drought stress and severe drought stress in oil palm seedlings could widen xylem diameter, phloem diameters, strengthen cell such as epidermal cells, cortex cells, thickness of endodermic cells, thickness of sclerenchyma cells and increase hardness of cell compared to field capacity. As for the parameters of thick endodermic cells, stele diameter and sclerenchyma diameter, an addition of 50% K could give higher results.

Sign in / Sign up

Export Citation Format

Share Document