scholarly journals Gas exchange, biomass and non-structural carbohydrates dynamics in vines under combined drought and biotic stress

2019 ◽  
Vol 19 (1) ◽  
Author(s):  
Tadeja Savi ◽  
Almudena García González ◽  
Jose Carlos Herrera ◽  
Astrid Forneck
Keyword(s):  
Biotic Stress ◽  
Carbon Metabolism ◽  
Water Status ◽  
Water Shortage ◽  
Sink Strength ◽  
Negative Effects ◽  
Whole Plant ◽  
Leaf Level ◽  
Effects Of Drought ◽  
Near Future

Abstract Background Intensity of drought stress and pest attacks is forecasted to increase in the near future posing a serious threat to natural and agricultural ecosystems. Knowledge on potential effects of a combined abiotic-biotic stress on whole-plant physiology is lacking. We monitored the water status and carbon metabolism of a vine rootstock with or without scion subjected to water shortening and/or infestation with the sucking insect phylloxera (Daktulosphaira vitifoliae Fitch). We measured non-structural carbohydrates and biomass of different plant organs to assess the stress-induced responses at the root, stem, and leaf level. Effects of watering on root infestation were also addressed. Results Higher root infestation was observed in drought-stressed plants compared to well-watered. The drought had a significant impact on most of the measured functional traits. Phylloxera further influenced vines water and carbon metabolism and enforced the sink strength of the roots by stimulating photosynthates translocation. The insect induced carbon depletion, reprogramed vine development, while preventing biomass compensation. A synergic effect of biotic-abiotic stress could be detected in several physiological and morphological traits. Conclusions Our results indicate that events of water shortage favour insects’ feeding damage and increase the abundance of root nodosities. Root phylloxera infestation imposes a considerable stress to the plants which might exacerbate the negative effects of drought.

scholarly journals EFFECTS OF CONTINUOUS LIGHTING ON ENZYME ACTIVITIES OF LEAF CARBON METABOLISM OF TOMATO AND PEPPER PLANTS

HortScience ◽  
1994 ◽  
Vol 29 (4) ◽  
pp. 250a-250 ◽  
Author(s):  
Dominique-André Demers ◽  
Serge Yelle ◽  
André Gosselin
Keyword(s):  
Carbon Metabolism ◽  
Sucrose Phosphate Synthase ◽  
Starch Accumulation ◽  
Sink Strength ◽  
Negative Effects ◽  
Tomato Plants ◽  
Leaf Chlorosis ◽  
Leaf Level ◽  
Long Photoperiod ◽  
Pepper Plants

Exposure of tomato and pepper plants to long photoperiods (20 hours or more for tomato; 24 hours for pepper) results in leaf chlorosis (tomato), leaf deformities (pepper), and decreased growth and productivity (both species). Some researchers have suggested that excessive starch accumulation in the leaves could be the cause of the negative effects. We observed that tomato and pepper plants do accumulate more starch in their leaves when grown under a long photoperiod (24 hours) compared to a shorter one (16 hours). However, our results indicated that these accumulations were not caused by a limited sink strength but by an alteration of the carbon metabolism at the leaf level. In our last experiment, we studied the activity of enzymes [sucrose phosphate synthase (SPS), sucrose synthase (SS), invertase] of leaf carbon metabolism in tomato and pepper plants grown under different photoperiods (natural, natural + supplemental light of 100 μmol·m-2·s-1 during 16 and 24 hours). We observed a 10% to 15% decrease in leaf SPS activity in tomato (not in pepper) plants grown under a 24-hour photoperiod. In both species, invertase and SS activities were not affected by photoperiod treatments. In tomato plants grown under a 24-hour photoperiod, the decrease in SPS activity corresponded to the appearance of leaf chlorosis (6 to 7 weeks after the beginning of treatments). Therefore, it appears that leaf carbon metabolism could be involved in the development of negative effects of long photoperiod in tomato plants, but not in pepper plants. The fact that photoperiod had no apparent effect on leaf carbon metabolism of pepper may explain why this species can tolerate longer photoperiods than tomato plants.

Whole-Plant Responses to Drought

1986 ◽  
Vol 13 (1) ◽  
pp. 127 ◽  
Author(s):  
ED Schulze
Keyword(s):  
Gas Exchange ◽  
Water Status ◽  
Carbon Assimilation ◽  
Water Shortage ◽  
Root Tip ◽  
Plant Responses ◽  
Root Shoot Ratio ◽  
Whole Plant ◽  
Plant Level ◽  
Stomatal Functioning

The partitioning of carbon and interactions which cause limitations on gas exchange and growth under conditions of a limited supply of water and nutrients are discussed. Possible mechanisms of effects of air humidity on stomatal functioning and carbon assimilation are described. Also, it is shown that stomata respond to a signal from the root when the soil dries out prior to leaf wilting. Stomatal conductance determines canopy transpiration if the aerodynamic boundary layer resistance is low, such as in trees. Water shortage significantly affects extension growth and the root-shoot ratio at the whole- plant level. But experiments with xylem-tapping mistletoes show that stem growth can also be promoted by the presence of the mistletoe even when there is no apparent signal from the subtending shoot except the flow in the stem xylem. It appears that the internal plant water status may not affect gas exchange and carbon partitioning unless the plant fails to maintain a flow of water through the leaf epidermis and root tip.

scholarly journals The contribution of PIP2-type aquaporins to photosynthetic response to increased vapour pressure deficit

2021 ◽  
Author(s):  
D Israel ◽  
S Khan ◽  
C R Warren ◽  
J J Zwiazek ◽  
T M Robson
Keyword(s):  
Vapour Pressure Deficit ◽  
Air Humidity ◽  
Wild Type ◽  
Knockout Mutant ◽  
Evaporative Demand ◽  
Co2 Transport ◽  
Whole Plant ◽  
Knockout Mutants ◽  
Leaf Level ◽  
Low Humidity

Abstract The roles of different plasma membrane aquaporins (PIPs) in leaf-level gas exchange of Arabidopsis thaliana were examined using knockout mutants. Since multiple Arabidopsis PIPs are implicated in CO2 transport across cell membranes, we focused on identifying the effects of the knockout mutations on photosynthesis, and whether they are mediated through the control of stomatal conductance of water vapour (gs), mesophyll conductance of CO2 (gm) or both. We grew Arabidopsis plants in low and high humidity environments and found that the contribution of PIPs to gs was larger under low air humidity when the evaporative demand was high, whereas any effect of lacking PIP function was minimal under higher humidity. The pip2;4 knockout mutant had 44% higher gs than the wild type plants under low humidity, which in turn resulted in an increased net photosynthetic rate (Anet). We also observed a 23% increase in whole-plant transpiration (E) for this knockout mutant. The lack of functional AtPIP2;5 did not affect gs or E, but resulted in homeostasis of gm despite changes of humidity, indicating a possible role in regulating CO2 membrane permeability. CO2 transport measurements in yeast expressing AtPIP2;5 confirmed that this aquaporin is indeed permeable to CO2.

Involvement of dehydrin proteins in mitigating the negative effects of drought stress in plants

2021 ◽  
Author(s):  
Riyazuddin Riyazuddin ◽  
Nisha Nisha ◽  
Kalpita Singh ◽  
Radhika Verma ◽  
Ravi Gupta
Keyword(s):  
Drought Stress ◽  
Negative Effects ◽  
Effects Of Drought

Penconazole and calcium ameliorate drought stress in canola by upregulating the antioxidative enzymes

2020 ◽  
Vol 47 (9) ◽  
pp. 825 ◽  
Author(s):  
Maryam Rezayian ◽  
Vahid Niknam ◽  
Hassan Ebrahimzadeh
Keyword(s):  
Oxidative Stress ◽  
Lipid Peroxidation ◽  
Drought Stress ◽  
Drought Tolerance ◽  
Antioxidative Enzymes ◽  
Proline Content ◽  
Fresh Weight ◽  
Negative Effects ◽  
Mda Content ◽  
Effects Of Drought

The aim of this research was to gauge the alternations in the lipid peroxidation and antioxidative enzyme activity in two cultivars (cv. RGS003 and cv. Sarigol) of canola under drought stress and drought tolerance amelioration by penconazole (PEN) and calcium (Ca). Plants were treated with different polyethylene glycol (PEG) concentrations (0, 5, 10 and 15%) without or with PEN (15 mg L–1) and Ca (15 mM). The Ca treatment prevented the negative effects of drought on fresh weight (FW) in RGS003 and Sarigol at 5 and 15% PEG respectively. Ca and PEN/Ca treatments caused significant induction in the proline content in Sarigol at 15% PEG; the latter treatment was accompanied by higher glycine betaine (GB), lower malondialdehyde (MDA) and growth recovery. Hydrogen peroxide (HO2) content in Sarigol was proportional to the severity of drought stress and all PEN, Ca and PEN/Ca treatments significantly reduced the H2O2 content. PEN and PEN/Ca caused alleviation of the drought-induced oxidative stress in RGS003. RGS003 cultivar exhibited significantly higher antioxidative enzymes activity at most levels of drought, which could lead to its drought tolerance and lower MDA content. In contrast to that of Sarigol, the activity of catalase and superoxide dismutase (SOD) increased with Ca and PEN/Ca treatments in RGS003 under low stress. The application of PEN and Ca induced significantly P5CS and SOD expression in RGS003 under drought stress after 24 h. Overall, these data demonstrated that PEN and Ca have the ability to enhance the tolerance against the drought stress in canola plants.

scholarly journals ALLELOPATHIC INFLUENCE OF TRIANTHIMA PORTULACASTRUM L. ON GROWTH AND DEVELOPMENTAL RESPONSES OF SESAME (SESAMUM INDICUM L.)

2017 ◽  
Vol 4 (2) ◽  
pp. 183-186
Author(s):  
Prabhakaran J ◽  
Kavitha D
Keyword(s):  
Block Design ◽  
Dry Weight ◽  
Germination Percentage ◽  
Sesamum Indicum ◽  
Negative Effects ◽  
Chlorophyll Contents ◽  
Whole Plant ◽  
Low Concentrations ◽  
Seedling Length ◽  
Developmental Responses

An experiment was conducted in order to determine the allelopathic effects of the aqueous extract of Trianthima portulacastrum L.on the seed germination, seedling growth and chlorophyll content ofsesame (Sesamum indicum L.). Greenhouse experiment was carried out as RCBD (Randomized complete block design)with four replications. Treatments included 0, 1, 2, 3 and 4% (W/W) residues of whole plant of T.portulacastrum with normal field soil. Results showed that the low concentrations of T.portulacastrum had no significant effect on the germination percentage, seedling length, dry weight, total chlorophyll contents at lower concentration(1%) of weed residues. However, treatments with higher concentrations had negative effects on germination, growth and seedling dry weight of sesame.

scholarly journals The water crisis and its implications in Brazilian agribusiness: A bibliographic review

2020 ◽  
Vol 13 (1) ◽  
pp. 42
Author(s):  
O. S. Fagundes ◽  
L. C. A. Oliveira ◽  
O. M. Yamashita ◽  
I. V. Silva ◽  
M. A. C. Carvalho ◽  
...  
Keyword(s):  
Water Resources ◽  
Agricultural Practices ◽  
Industrial Effluents ◽  
Water Shortage ◽  
Irrigated Agriculture ◽  
Water Crisis ◽  
Negative Effects ◽  
Economic Sectors ◽  
Basic Sanitation ◽  
Environmental Good

Water scarcity has become one of the main global problems, since of all the water of the terrestrial surface, only 2.5% represents fresh water, and of this, only 0.3% corresponds to the water of the rivers and lakes that are available to supply the demand for food production and other uses. The present work consisted in surveying the scenario related to the global water crisis and presenting evidence that even Brazil being abundant in the amount of water available, tends to face serious problems because of its scarcity, affecting two of the main economic pillars, agribusiness and industry. It was observed that the main negative effects on water resources occur due to urban occupation and agricultural practices in a disorderly way, causing destruction of natural resources through the discharge of domestic sewage, industrial effluents and agrochemicals. In general, the lack of control of the use of the water directed to the productive processes is one of the major generators of the water shortage, since 69% of the water derived from rivers, lakes and aquifers underground is turned to irrigated agriculture, using 70 times more water than for domestic purposes. Thus, it is necessary to adopt policies aimed at the conservation and efficient use of water resources, to value water as a social, social and environmental good, since their scarcity can generate instability in economic sectors such as agriculture, generating production insecurity in industry, as well as affecting the supply of drinking water, basic sanitation and public health.

scholarly journals IMPACT OF GLOBALIZATION ON THE FOLK LIFE OF THE TRIBES OF NORTH EAST INDIA

2019 ◽  
pp. 29-30
Author(s):  
Mr. Bikash Das
Keyword(s):  
Life Style ◽  
Traditional Culture ◽  
Northeast India ◽  
Negative Effects ◽  
North East India ◽  
North East ◽  
Secondary Information ◽  
The Impact ◽  
Near Future

Northeast India is a diverse region of our country. It is a resident of different tribes. Some of these are- Bodo, Kuki, Mizo, Singpfo, Khasi, Mishing, Deori, Adi, Apatani, Naga, Garo, Nishi, Rengma, Angami, Rabha etc. Each tribe have their rich traditional culture. They are famous for their unique traditional life style. But globalization stands as an effecting factor on the folk life of the Northeastern tribes. This paper is an attempt to analyze the impact of globalization on the folk life of the various tribes of Northeast India. In the context of the tribes of Northeast India, it is predicted that globalization may be harmfull for their unique identities. The study is based on primary and secondary information collected for various tribes of Northeast India. The study founded that globalization has some negative effects on the folk life of the Northeastern tribes. However, it is hoped that in near future, globalization may be helpfull for the tribes of Northeast India. KEYWORDS: Ethnic, Folk Life, Globalization, Northeast, Tribal.

scholarly journals Biochar addition alleviate the negative effects of drought and salinity stress on soybean productivity and water use efficiency

2020 ◽  
Author(s):  
Yaojun Zhang ◽  
Jiaqi Ding ◽  
Hong Wang ◽  
Lei Su ◽  
Cancan Zhao
Keyword(s):  
Grain Yield ◽  
Water Use Efficiency ◽  
Water Use ◽  
Salinity Stress ◽  
Crop Growth ◽  
Interactive Effects ◽  
Gaseous Exchange ◽  
Negative Effects ◽  
Use Efficiency ◽  
Effects Of Drought

Abstract Background: Environmental stress is a crucial factor restricting plant growth as well as crop productivity, thus influencing the agricultural sustainability. Biochar addition is proposed as an effective management to improve crop performance. However, there were few studies focused on the effect of biochar addition on crop growth and productivity under interactive effect of abiotic stress (e.g., drought and salinity). This study was conducted with a pot experiment to investigate the interaction effects of drought and salinity stress on soybean yield, leaf gaseous exchange and water use efficiency (WUE) under biochar addition. Results: Drought and salinity stress significantly depressed soybean phenology (e.g. flowering time) and all the leaf gas exchange parameters, but had inconsistent effects on soybean root growth and WUE at leaf and yield levels. Salinity stress significantly decreased photosynthetic rate, stomatal conductance, intercellular CO2 concentration and transpiration rate by 20.7%, 26.3%, 10.5% and 27.2%, respectively. Lower biomass production and grain yield were probably due to the restrained photosynthesis under drought and salinity stress. Biochar addition significantly enhanced soybean grain yield by 3.1-14.8%. Drought stress and biochar addition significantly increased WUE-yield by 27.5% and 15.6%, respectively, while salinity stress significantly decreased WUE-yield by 24.2%. Drought and salinity stress showed some negative interactions on soybean productivity and leaf gaseous exchange. But biochar addition alleviate the negative effects on soybean productivity and water use efficiency under drought and salinity stress. Conclusions: The results of the present study indicated that drought and salinity stress could significantly depress soybean growth and productivity. There exist interactive effects of drought and salinity stress on soybean productivity and water use efficiency, while we could employ biochar to alleviate the negative effects. We should consider the interactive effects of different abiotic restriction factors on crop growth thus for sustainable agriculture in the future.

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