Short-Time of Rehydration is not Effective to Re-Establish Chlorophyll Fluorescence and Gas Exchange in Two Cowpea Cultivars Submitted to Water Deficit

Low water supply frequently interferes on chlorophyll fluorescence and gas exchange. This study aimed to answer if a short-time of rehydration is efficient to re-establish chlorophyll fluorescence and gas exchange in cowpea plants. The experiment used four treatments (sensitive / water deficit, sensitive / control, tolerant / water deficit and tolerant / control). The sensitive and tolerant cultivars after water restriction had significant changes in gas exchange. On the third day, the stress caused lower for PN and gs in sensitive cultivar of 67% and 45%, respectively. After rehydration these parameters were not recovered significantly to two cultivars. In relation to chlorophyll fluorescence, water stress caused significant changes in all parameters evaluated of cultivars, being observed effects more intense on sensitive cultivar in the parameters Fv/Fm (38%) and Fo (69%). Rehydration did not promote recovery of the values of Fv/Fm and Fo to sensitive cultivar. Therefore, our study revealed that a short-time of rehydration is not effective to re-establish chlorophyll fluorescence and gas exchange in cowpea plants submitted to water deficit.

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The effect of water deficit on some physiological indices of Indian lettuce (Lactuca indica L.)

Journal of Science Natural Science ◽

10.18173/2354-1059.2021-0010 ◽

2021 ◽

Vol 66 (1) ◽

pp. 80-86

Author(s):

Thin Pham Thi Thanh ◽

Bang Cao Phi ◽

Hai Nguyen Thi Thanh ◽

Khuynh Bui The ◽

Mai Nguyen Phuong ◽

...

Keyword(s):

Chlorophyll Fluorescence ◽

Water Stress ◽

Water Content ◽

Flowering Time ◽

Water Deficit ◽

Physiological Responses ◽

Water Deficit Stress ◽

Flower Formation ◽

Lactuca Indica ◽

Wilting Rate

Indian Lettuce (Lactuca indica L.) is a valuable medicinal herb but there are still no many researches about this plant. In this work, the physiological responses of Indian lettuce plants under water deficit conditions (5, 8, and 11 days of water stress) were investigated. The Indian lettuce wilted after 5 days of water stress (66.66%), the wilting rate increased after 8 (93.33%) and 11 days (100%) of water stress. The longer duration of water deficit stress caused the slower recovery of plants after rewatering. The water deficit stress caused a decrease in chlorophyll fluorescence, non-associated water content as well as flower formation of Indian lettuce. But the water deficit stress increases the associated water content and the flowering time of this plant.

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PHYSIOLOGICAL RESPONSES OF THREE WOODY SPECIES SEEDLINGS UNDER WATER STRESS, IN SOIL WITH AND WITHOUT ORGANIC MATTER

Revista Árvore ◽

10.1590/0100-67622016000300009 ◽

2016 ◽

Vol 40 (3) ◽

pp. 455-464 ◽

Cited By ~ 1

Author(s):

Maria da Assunção Machado Rocha ◽

Claudivan Feitosa de Lacerda ◽

Marlos Alves Bezerra ◽

Francisca Edineide Lima Barbosa ◽

Hernandes de Oliveira Feitosa ◽

...

Keyword(s):

Organic Matter ◽

Water Stress ◽

Gas Exchange ◽

Leaf Gas Exchange ◽

Water Status ◽

Near Field ◽

Limiting Factors ◽

Water Restriction ◽

Soil Water Retention ◽

African Mahogany

ABSTRACT The low availability of water in the soil is one of the limiting factors for the growth and survival of plants. The objective of this study was to evaluate the responses of physiological processes in early growth of guanandi (Calophyllum brasilense Cambess), African mahogany (Khayai vorensis A. Chev) and oiti (Licaniato mentosa Benth Fritsch) over a period of water stress and other of rehydration in the soil with and without addition of organic matter. The study was conducted in a greenhouse and the experimental design was completely randomised into a 3 x 2 x 2 factorial scheme, comprising three species (guanandi, African mahogany, and oiti), two water regimes (with and without water restriction) and two levels of organic fertilisation (with and without the addition of organic matter). Irrigation was suspended for 15 days in half of the plants, while the other half (control) continued to receive daily irrigation, the soil being maintained near field capacity for these plants. At the end of the stress period, the plants were again irrigated for 15 days to determine their recovery. Water restriction reduced leaf water potential and gas exchange in the three species under study, more severely in soil with no addition of organic matter. The addition of this input increased soil water retention and availability to the plants during the suspension of irrigation, reducing the detrimental effects of the stress. During the period of rehydration, there was strong recovery of water status and leaf gas exchange. However recovery was not complete, suggesting that some of the effects caused by stress irreversibly affected cell structures and functions. However, of the species being studied, African mahogany displayed a greater sensitivity to stress, with poorer recovery.

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Chitosan application in the induction of water deficit tolerance in maize plants

Acta Scientiarum Agronomy ◽

10.4025/actasciagron.v42i1.42463 ◽

2019 ◽

Vol 42 ◽

pp. e42463

Author(s):

Lorena Gabriela Almeida ◽

Paulo César Magalhães ◽

Décio Karam ◽

Eder Marcos da Silva ◽

Amauri Alves Alvarenga

Keyword(s):

Hydrogen Peroxide ◽

Lipid Peroxidation ◽

Antioxidant Enzymes ◽

Gas Exchange ◽

Water Deficit ◽

Foliar Application ◽

Water Restriction ◽

Biophysical Parameters ◽

Relative Water ◽

Maize Plants

The present research seeks to elucidate the feasibility of chitosan (CHT) in the induction of water deficit tolerance in different maize hybrids, contrasting tolerance to water restriction, tolerance and sensitivity. The maize plants were subjected to water deficit and foliar application of different chitosan doses (60, 100, 140, and 180 mg L-1) at the pre-flowering growth stage and evaluated during the stress period of fifteen days. To understand the induction behaviour of the tolerance to water restriction, biophysical parameters, such as water potential, relative water content and chlorophyll content, gas exchange, and biochemical assays, were quantified based on the activity of SOD, CAT, APX, and PAL antioxidant enzymes, lipid peroxidation activity and hydrogen peroxide content. Among the treatments, maize plants subjected to chitosan foliar application at a dose of 140 mg L-1 presented similar behavioural responses to plants under favourable irrigation conditions. Such positive responses are related to the high degree of activity of antioxidant enzymes, gas exchange and low levels of lipid peroxidation and hydrogen peroxide. The results support the potential use of CHT to increase tolerance to water stress.

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Continuous Chlorophyll Fluorescence and Gas Exchange Measurements as A New Approach to Study Water Stress Effects on Leaf Photosynthesis

Photosynthesis: Mechanisms and Effects ◽

10.1007/978-94-011-3953-3_995 ◽

1998 ◽

pp. 4305-4308 ◽

Cited By ~ 2

Author(s):

Jaume Flexas ◽

Jean-Marie Briantais ◽

Zoran Cerovic ◽

Hipólito Medranol ◽

Ismael Moya

Keyword(s):

Chlorophyll Fluorescence ◽

Water Stress ◽

Gas Exchange ◽

Leaf Photosynthesis ◽

New Approach ◽

Stress Effects

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Water: the most important ‘molecular’ component of water stress tolerance research

Functional Plant Biology ◽

10.1071/fp13149 ◽

2013 ◽

Vol 40 (12) ◽

pp. 1310 ◽

Cited By ~ 54

Author(s):

Vincent Vadez ◽

Jana Kholova ◽

Mainassara Zaman-Allah ◽

Nouhoun Belko

Keyword(s):

Water Stress ◽

Water Supply ◽

Water Deficit ◽

Plant Traits ◽

Supply And Demand ◽

Limiting Factor ◽

Management Options ◽

Major Drawback ◽

Water Stress Tolerance ◽

Water Supply And Demand

Water deficit is the main yield-limiting factor across the Asian and African semiarid tropics and a basic consideration when developing crop cultivars for water-limited conditions is to ensure that crop water demand matches season water supply. Conventional breeding has contributed to the development of varieties that are better adapted to water stress, such as early maturing cultivars that match water supply and demand and then escape terminal water stress. However, an optimisation of this match is possible. Also, further progress in breeding varieties that cope with water stress is hampered by the typically large genotype × environment interactions in most field studies. Therefore, a more comprehensive approach is required to revitalise the development of materials that are adapted to water stress. In the past two decades, transgenic and candidate gene approaches have been proposed for improving crop productivity under water stress, but have had limited real success. The major drawback of these approaches has been their failure to consider realistic water limitations and their link to yield when designing biotechnological experiments. Although the genes are many, the plant traits contributing to crop adaptation to water limitation are few and revolve around the critical need to match water supply and demand. We focus here on the genetic aspects of this, although we acknowledge that crop management options also have a role to play. These traits are related in part to increased, better or more conservative uses of soil water. However, the traits themselves are highly dynamic during crop development: they interact with each other and with the environment. Hence, success in breeding cultivars that are more resilient under water stress requires an understanding of plant traits affecting yield under water deficit as well as an understanding of their mutual and environmental interactions. Given that the phenotypic evaluation of germplasm/breeding material is limited by the number of locations and years of testing, crop simulation modelling then becomes a powerful tool for navigating the complexity of biological systems, for predicting the effects on yield and for determining the probability of success of specific traits or trait combinations across water stress scenarios.

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Stress Metabolism III. Variations in Response to Water Deficit in the Barley Plant

Australian Journal of Biological Sciences ◽

10.1071/bi9730065 ◽

1973 ◽

Vol 26 (1) ◽

pp. 65 ◽

Cited By ~ 52

Author(s):

TN Singh ◽

IG Paleg ◽

D Aspinall

Keyword(s):

Water Stress ◽

Water Supply ◽

Water Deficit ◽

Controlled Environment ◽

Barley Plant ◽

Stress History ◽

History Of ◽

Leaf Tissues ◽

Response To Water ◽

Periods Of Stress

Barley plants (cv. Prior) were grown in soil in a controlled environment and subjected to one, two, or three cycles of water stress by witholding water for short periods interspersed with periods of adequate water supply. The water potentials of the leaf tissues during and following these periods of stress were unaffected by the previous stress history of the plants.

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Silicon and boron mitigate the effects of water deficit on sunflower

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v23n3p175-182 ◽

2019 ◽

Vol 23 (3) ◽

pp. 175-182 ◽

Cited By ~ 3

Author(s):

Jose M. G. Neves ◽

Leonardo A. de Aquino ◽

Paulo G. Berger ◽

Júlio C. L. Neves ◽

Genelício C. Rocha ◽

...

Keyword(s):

Chlorophyll Fluorescence ◽

Water Stress ◽

Experimental Design ◽

Water Deficit ◽

Magnesium Silicate ◽

Dolomitic Limestone ◽

Chlorophyll Fluorescence Parameters ◽

Fluorescence Parameters ◽

Calcium Magnesium ◽

Beginning Of Flowering

ABSTRACT The objective of this study was to evaluate the effect of Ca and Mg silicate and B on the gas exchange, leaf water potential and chlorophyll fluorescence parameters in the sunflower variety Embrapa 122 -V2000 under water stress conditions. The trial was conducted in Red Yellow Latosol with very clayey texture, with contrasting levels of Si and B and subjected to water deficit. The experimental design was randomized blocks in a 24 factorial arrangement, with five replicates. Treatments consisted of the combination of two acidity corrective agents (calcium magnesium silicate and dolomitic limestone), two levels of base saturation (30 and 70%), two levels of B (0.18 mg dm-3 - value available in the soil and 1.20 mg dm-3) and two water regimes (with and without water stress from the beginning of flowering). It can be concluded that the supply of Si and B can reduce the damage to sunflower caused by water stress.

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