scholarly journals Effects of Drought Stress During Critical Periods on Photosynthesis Characteristics and Production Performance of Naked Oat (Avena Nuda. L)

Author(s):  
Xinjun Zhang ◽  
Wenting Liu ◽  
Yaci Lv ◽  
Tianliang Li ◽  
Jianzhao Tang ◽  
...  

Abstract Revealing the effects of drought stress during the critical period on the photosynthetic characteristics and production performance of naked oats could provide theoretical basis for optimizing the water managements and selecting the drought resistance cultivars. In this study, a potted experiment consisting of four water levels was conducted, to investigate the response of photosynthesis, chlorophyll fluorescence, biomass, yield and yield components of to drought stress during 12-15 days before heading at a typical site in Zhangjiakou. Results showed that the initial chlorophyll fluorescence rate (Fo) increased by 9.03-50.92% under drought stress, while the maximum fluorescence rate (Fm) and photochemical efficiency (Fv/Fm) decreased by 8.49-19.73% and 10.37-24.12%. Moreover drought stress decreased the photosynthetic rate (Pn), transpiration rate (Tr), stomatal conductance (Gs). The CO2 concentration (Ci) decreased under light drought stress, while increased under moderate and severe drought stress. Drought stress during critical periods also had significant impacts on oat yield and yield components. Oat yields decreased by 9.5-12.7%, 16.8-27.0% and 44.1-47.7% under light, moderate and sever drought stress, respectively. The yield components such as grains per spike, 1000-grain weight were decreased by 1.7-12.5%, 8.3-24.3%, 32.7-34.2% and 5.7-8.6%, 12.7-14.5%, 16.8-19.1% under light, moderate and severe drought stress, respectively. But the Spike numbers were not signifigantly different between different treatments. Our study explored the impacts of drought stress on the photosynthetic characteristics and production performance of naked oats, which had significance for enhancing the production efficiency for oat under drought stress.

Water ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 793
Author(s):  
Juanli Chen ◽  
Xueyong Zhao ◽  
Yaqiu Zhang ◽  
Yuqiang Li ◽  
Yongqing Luo ◽  
...  

Artemisia halodendron is a widely distributed native plant in China’s Horqin sandy land, but few studies have examined its physiological responses to drought and rehydration. To provide more information, we investigated the effects of drought and rehydration on the chlorophyll fluorescence parameters and physiological responses of A. halodendron to reveal the mechanisms responsible for A. halodendron’s tolerance of drought stress and the resulting ability to tolerate drought. We found that A. halodendron had strong drought resistance. Its chlorophyll content first increased and then decreased with prolonged drought. Variable chlorophyll fluorescence (Fv) and quantum efficiency of photosystem II (Fv/Fm) decreased, and the membrane permeability and malondialdehyde increased. When plants were subjected to drought stress, superoxide dismutase (SOD) activity degraded under severe drought, but the activities of peroxidase (POD) and catalase (CAT) and the contents of soluble proteins, soluble sugars, and free proline increased. Severe drought caused wilting of A. halodendron leaves and the leaves failed to recover even after rehydration. After rehydration, the chlorophyll content, membrane permeability, SOD and CAT activities, and the contents of the three osmoregulatory substances under moderate drought began to recover. However, Fv, Fv/Fm, malondialdehyde, and POD activity did not recover under severe drought. These results illustrated that drought tolerance of A. halodendron resulted from increased enzyme (POD and CAT) activities and accumulation of osmoregulatory substances.


2015 ◽  
Vol 41 (1) ◽  
pp. 154 ◽  
Author(s):  
Xing-Hua ZHANG ◽  
Jie GAO ◽  
Wei-Li DU ◽  
Ren-He ZHANG ◽  
Ji-Quan XUE

Cells ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 261
Author(s):  
Md. Mahadi Hasan ◽  
Milan Skalicky ◽  
Mohammad Shah Jahan ◽  
Md. Nazmul Hossain ◽  
Zunaira Anwar ◽  
...  

In recent years, research on spermine (Spm) has turned up a lot of new information about this essential polyamine, especially as it is able to counteract damage from abiotic stresses. Spm has been shown to protect plants from a variety of environmental insults, but whether it can prevent the adverse effects of drought has not yet been reported. Drought stress increases endogenous Spm in plants and exogenous application of Spm improves the plants’ ability to tolerate drought stress. Spm’s role in enhancing antioxidant defense mechanisms, glyoxalase systems, methylglyoxal (MG) detoxification, and creating tolerance for drought-induced oxidative stress is well documented in plants. However, the influences of enzyme activity and osmoregulation on Spm biosynthesis and metabolism are variable. Spm interacts with other molecules like nitric oxide (NO) and phytohormones such as abscisic acid, salicylic acid, brassinosteroids, and ethylene, to coordinate the reactions necessary for developing drought tolerance. This review focuses on the role of Spm in plants under severe drought stress. We have proposed models to explain how Spm interacts with existing defense mechanisms in plants to improve drought tolerance.


2013 ◽  
Vol 46 (1) ◽  
pp. 23-32 ◽  
Author(s):  
F. Monjezi ◽  
F. Vazin ◽  
M. Hassanzadehdelouei

Abstract In hot and arid regions, drought stress is considered as one of the main reasons for yield reduction. To study the effect of drought stress, iron and zinc spray on the yield and yield components of wheat, an experiment was carried out during the crop seasons of 2010 and 2011 on Shahid Salemi Farm in Ahwaz as a split factorial within randomized complete block design with three replications. The main plots with irrigation factor and three levels were considered: Level A) full irrigation, Level B) stopping irrigation at pollination step, and Level C) stopping irrigation at the seed filling stage. Subsidiary plots were considered with and without iron and zinc spray. Influencing the seed filling process, in interaction with iron, wich is an important leaf's chlorophyll cation, zinc increased the seed yield. The drought stress reduced the thousand kernels weight (TKW) and the number of seeds per spike increased about 24% and 8.5% more than the one of control treatment, respectively. Using iron, as compared with control treatment, causes the increase of thousand kernels weight from 45.71 to 46.83 grams and the increase of spike from 49.51 to 51.73. Zinc spray increased seed yield and thousand kernels weight. The results obtained from the present research showed that iron and zinc spray has fairly improved the effects caused by drought stress.


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 ◽  
...  

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.


Sign in / Sign up

Export Citation Format

Share Document