Calcium Ameliorates the Tolerance of Lisianthus [Eustoma grandiflorum (Raf.) Shinn.] to Alkalinity in Irrigation Water

Irrigation water high in alkalinity can severely compromise the growth and marketability of ornamental plants. In the present study we investigated the response of lisianthus to increased calcium (Ca) when irrigated with solutions containing high levels of bicarbonate (HCO3−)-induced alkalinity. Alkalinity in irrigation water reduced the growth of lisianthus; however, plants supplemented with an increased concentration of Ca at alkalinity levels from 4 to 7 meq·L−1 of HCO3– exhibited improved growth and dry mass (DM) accumulation or were not detrimentally affected, demonstrating that Ca contributes to the increase of the tolerance of lisianthus to alkalinity. Supplementary Ca did maintain a high stomatal conductance (gS) and transpiration rate when alkalinity was at 4 meq·L−1, which explained the lower water potential in young leaves. Plants irrigated with solutions containing supplementary Ca had higher total DM, which was associated with a higher gS; however, when conductance was higher than 0.280 cm·s−1, like in plants with no supplementary Ca, DM tended to decrease. At a typical Ca concentration, there was a disruption on stomata functioning as gS and transpiration rate increased, which was associated with a reduction in shoot potassium (K). Calcium ameliorated the uptake of K when alkalinity was 4 meq·L−1 by allowing a less marked reduction in shoot K concentration. Chlorophyll was reduced by increasing alkalinity as a result of a decrease in shoot iron (Fe); however, supplementary Ca also contributed in increasing plant tolerance to alkalinity at 4 meq·L−1 by sustaining a high shoot Fe concentration. Supplementary Ca increased catalase and peroxidase activities, indicating that lisianthus responded to the stress by enhancing the activity of these enzymes to reduce oxidative damage.

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Development and Correction of K-deficiency in Drip-irrigated Apple

HortScience ◽

10.21273/hortsci.33.2.258 ◽

1998 ◽

Vol 33 (2) ◽

pp. 258-261 ◽

Cited By ~ 11

Author(s):

Gerry Neilsen ◽

Peter Parchomchuk ◽

Michael Meheriuk ◽

Denise Neilsen

Keyword(s):

Irrigation Water ◽

Titratable Acidity ◽

Growing Season ◽

Dry Mass ◽

The Third ◽

Red Color ◽

K Deficiency ◽

K Concentration ◽

K Fertilization ◽

Extractable Soil

Various schedules of 40 g N and 17.5 g P/tree per year were applied with irrigation water (fertigation) to `Summerland McIntosh' apple (Malus ×domestica Borkh.) trees on M.9 rootstock commencing the year of planting. Leaf K concentrations averaged 0.82% dry mass, indicating deficiency, by the third growing season. This coincided with extractable soil K concentrations of 50-60 μg·g-1 soil in a narrow volume of the coarse-textured soil located within 0.3 m of the emitters. The decline in leaf K concentration was reversed and fruit K concentration increased by additions of K at 15-30 g/tree applied either as granular KCl directly beneath the emitters in spring or as KCl applied as a fertigant in the irrigation water. K-fertilization increased fruit red color, size, and titratable acidity only when leaf K concentration was <1%. Fruit Ca concentration and incidence of bitter pit or coreflush were unaffected by K application. NPK-fertigation commencing upon tree establishment is recommended for high-density apple orchards planted on similar coarse-textured soils.

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Si attenuates the transpiration and increases both N assimilation and root development in the tomato under N availabilities

Australian Journal of Crop Science ◽

10.21475/ajcs.20.14.12.2771 ◽

2020 ◽

pp. 1926-1934

Author(s):

Roberta Corrêa Nogueirol ◽

Simone da Costa Mello ◽

João Cardoso de Souza Junior ◽

Rafael Gómez Arrieta ◽

Francisco Antonio Monteiro

Keyword(s):

Stomatal Conductance ◽

Glutamine Synthetase ◽

Plant Growth ◽

Root Development ◽

Transpiration Rate ◽

Mass Production ◽

Dry Mass ◽

High Availability ◽

Control Treatment ◽

Tomato Plants

Nitrogen (N) is the most important nutrient in crop productivity and silicon (Si) increases the uptake of nutrients and affect the uptake of N. The objective of this study was to evaluate the effect of Si combined with rates of N on the growth, root development, uptake of N and Si, assimilation of N, and photosynthesis of the tomato plants (Solanum lycopersicum). A factorial 3 × 3 was used, with rates of Si 0 (control treatment), 1, and 3 mmol L–1, and rates of N 5 (control treatment), 15, and 25 mmol L–1 in the nutrient solution. The rates of N did not affect the dry mass production and uptake of Si. However, the application of Si improved the plant growth and accumulation of Si and N. Relating to control treatment, the rate of Si 1 mmol L–1 increases the dry mass production and accumulation of Si and N in order of 52, 37, and 54 %, respectively. Although the rate of N did not increase the plant growth, it was verified that the N 15 mmol L–1 improves the concentration and accumulation of N in the shoots, and the relative concentration of chlorophyll with values of 43.5, 67, and 14 %, respectively, compared to the control. The supply of Si under low and high availability of N improved the glutamine synthetase, but at the rate of N 25 mmol L–1, a decrease in the transpiration rate and stomatal conductance was verified. Under the high availability of N, the glutamine synthetase raised 78 % as an effect of Si 3 mmol L–1 compared to control treatment (Si 0 mmol L–1). Nevertheless, the transpiration rate and stomatal conductance decreased 49 and 52 % under that condition. The excess of N 25 mmol L–1 negatively affected the root development, but under that condition, the application of Si increased the root length, root surface, and root hood in order of 70, 40, and 77 % compared to the control treatment. Application of Si is recommended for tomato growth, especially when cultivated with high N availability. The application of silicon enhances the plant growth, root development, nutrient uptake, nitrogen assimilation, and photosynthesis of the tomato plants cultivated under rates of N. We recommend the use of Si 3 mmol L–1 and N 15 mmol L–1 for the tomato plants under the nutrient solution

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Morphophysiological characteristics of okra plants submitted to saline stress in soil with organic fertilizer

Comunicata Scientiae ◽

10.14295/cs.v11i0.3241 ◽

2020 ◽

Vol 11 ◽

pp. e3241

Author(s):

Geocleber Gomes de Sousa ◽

Andreza de Melo Mendonça ◽

Jonnathan Richeds da Silva Sales ◽

Francisco Barroso da Silva Junior ◽

João Gutemberg Leite Moraes ◽

...

Keyword(s):

Stomatal Conductance ◽

Irrigation Water ◽

Organic Fertilizer ◽

Dry Mass ◽

Control Treatment ◽

Saline Stress ◽

Initial Growth ◽

Randomized Design ◽

Irrigation Water Salinity ◽

Salinity Levels

The excess of salts may compromise the growth and physiological functions of plants, but the use of bovine organic fertilizer can mitigate these effects. It was intended was to evaluate the saline stress in soil with and without bovine organic fertilizer on the initial growth, the accumulation of biomass and the gas exchanges of the okra culture. The test was conducted at the UNILAB’s experimental farm, in Piroás, in Redenção – CE city. The treatments were distributed in a completely randomized design with five replications, in a 5 x 2 factorial concerning five irrigation water salinity levels (1.0; 2.0; 3.0; 4.0 and 5.0 dS m-1), in the presence and absence of bovine organic fertilizer. Plant height, stem diameter, root length, a dry mass of shoot, photosynthesis, transpiration and stomatal conductance were evaluated. The bovine organic fertilizer promoted better means in initial growth and biomass in okra plants compared to the control treatment, thus showing efficiency in the attenuation of the salts present in irrigation water. The increase in the saline concentration of the irrigation water reduced the gas exchange (photosynthesis, stomatal conductance and transpiration) in okra plants. Nonetheless, in smaller proportions in the soil with the bovine organic fertilizer.

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Leaf Age Affects Gas Exchange in Okra

HortScience ◽

10.21273/hortsci.30.5.1017 ◽

1995 ◽

Vol 30 (5) ◽

pp. 1017-1019 ◽

Cited By ~ 9

Author(s):

W.F. Whitehead ◽

B.P. Singh

Keyword(s):

Stomatal Conductance ◽

Gas Exchange ◽

Transpiration Rate ◽

Leaf Age ◽

Leaf Expansion ◽

Abelmoschus Esculentus ◽

Leaf Emergence ◽

Leaf Aging ◽

Young Leaves

Two studies were conducted to assess the effects of leaf aging on gas exchange in okra [Abelmoschus esculentus (L.) Moench] leaves. Gas exchange was measured at 6- to 10-day intervals starting 15 days after leaf emergence (DFE) and continuing until senescence at 50 DFE. Rates of transpiration (E), stomatal conductance (gs) and CO2 exchange (CER) increased as leaves matured up to ≈25 DFE, about full leaf expansion. Transpiration rate, gs, and CER declined after 25 DFE and as leaves aged further. Internal leaf CO2 concentration (Ci) was higher in old than young leaves. This study suggests that the most efficient okra canopy would maximize exposure of 25-day-old leaves to sunlight.

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The Effects of Drought on Leaf Gas Exchange and Growth of Three Species of Herbaceous Perennials

HortScience ◽

10.21273/hortsci.33.3.540a ◽

1998 ◽

Vol 33 (3) ◽

pp. 540a-540

Author(s):

K.J. Prevete ◽

R.T. Fernandez

Keyword(s):

Drought Stress ◽

Stomatal Conductance ◽

Gas Exchange ◽

Drought Tolerance ◽

Transpiration Rate ◽

Leaf Gas Exchange ◽

Gas Analysis ◽

Herbaceous Perennials ◽

Effects Of Drought ◽

Analysis System

Three species of herbaceous perennials were tested on their ability to withstand and recover from drought stress periods of 2, 4, and 6 days. Eupatorium rugosum and Boltonia asteroides `Snowbank' were chosen because of their reported drought intolerance, while Rudbeckia triloba was chosen based on its reported drought tolerance. Drought stress began on 19 Sept. 1997. Plants were transplanted into the field the day following the end of each stress period. The effects of drought on transpiration rate, stomatal conductance, and net photosynthetic rate were measured during the stress and throughout recovery using an infrared gas analysis system. Leaf gas exchange measurements were taken through recovery until there were no differences between the stressed plants and the control plants. Transpiration, stomatal conductance, and photosynthesis of Rudbeckia and Boltonia were not affected until 4 days after the start of stress. Transpiration of Eupatorium decreased after 3 days of stress. After rewatering, leaf gas exchange of Boltonia and Rudbeckia returned to non-stressed levels quicker than Eupatorium. Growth measurements were taken every other day during stress, and then weekly following transplanting. Measurements were taken until a killing frost that occurred on 3 Nov. There were no differences in the growth between the stressed and non-stressed plants in any of the species. Plants will be monitored throughout the winter, spring, and summer to determine the effects of drought on overwintering capability and regrowth.

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Raw and Fermented Alfalfa Brown Juice Induces Changes in the Germination and Development of French Marigold (Tagetes patula L.) Plants

Plants ◽

10.3390/plants10061076 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1076

Author(s):

Döme Barna ◽

Szilvia Kisvarga ◽

Szilvia Kovács ◽

Gábor Csatári ◽

Ibolya O. Tóth ◽

...

Keyword(s):

Seed Germination ◽

Tap Water ◽

Germination Rate ◽

Ornamental Plants ◽

Dry Mass ◽

Water Soluble ◽

Tagetes Patula ◽

Root And Shoot Length ◽

Horticultural Practice ◽

Brown Juice

Organic and ecological farming programs require new and efficient biostimulants with beneficial properties for the sustainable and safe production of seedlings and ornamental plants. We examined the effect of non-fermented and lacto-fermented alfalfa brown juice (BJ) on seed germination and the vegetative, physiological, and anatomical properties of French marigold (Tagetes patula L. ‘Csemő’) plants which were treated with 0.5–10% fermented and non-fermented BJ, with tap water applied as a control. Applying 0.5% fermented BJ significantly improved seed germination compared with non-fermented BJ, resulting in an increase of 9.6, 11.2, 10.9, and 41.7% in the final germination percent, germination rate index, germination index, and vigor index, respectively. In addition, it increased the root and shoot length by 7.9 and 16.1%, respectively, root and shoot dry mass by 20 and 47.6%, respectively, and the number of leaves by 28.8% compared to the control. Furthermore, an increase in contents of water-soluble phenol, chlorophyll a and b, and carotenoid was reported upon the application of 0.5% fermented BJ, while peroxidase activity decreased. Our results prove that alfalfa BJ can be enrolled as a biostimulant as part of the circular farming approach which supports the sustainable horticultural practice.

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Production of Pityrocarpa moniliformis (Benth.) Luckow & R.W. Jobson (Fabaceae) seedlings irrigated with saline water

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v25n3p182-188 ◽

2021 ◽

Vol 25 (3) ◽

pp. 182-188

Author(s):

Adriana dos S. Ferreira ◽

Caio C. P. Leal ◽

Bruno da S. Guirra ◽

Salvador B. Torres ◽

Marco Porceddu ◽

...

Keyword(s):

Electrical Conductivity ◽

Irrigation Water ◽

Saline Water ◽

Block Design ◽

Soluble Sugars ◽

Dry Mass ◽

Initial Growth ◽

Saline Irrigation ◽

Total Soluble Sugars ◽

Chlorophylls A And B

ABSTRACT Saline irrigation water at high levels causes disturbance in the growth of more sensitive plants. The objective of this research was to evaluate the initial growth of Pityrocarpa moniliformis seedlings under different electrical conductivity in irrigation water through physiological and biochemical analyses. The experiment was conducted in a greenhouse with five water electrical conductivities (0.5, 2.0, 4.0, 6.0 and 8.0 dS m-1) and four repetitions of 20 plants each, arranged in a randomized block design. Application of the treatments with irrigation water containing NaCl began at 30 days after sowing. To determine the behaviour of the species, the following variables were analysed: stem diameter, plant height, number of leaves, leaf area, Dickson quality index, shoot dry mass, root dry mass and total dry mass, as well as the biochemical variables, such as the concentrations of total soluble sugars, free proline and chlorophylls a and b. The increase in irrigation water salinity hampered the growth of P. moniliformis seedlings, with electrical conductivity of 0.5 dS m-1 being the limit for maximum production. The results also indicated that the deleterious effects of salt stress on P. moniliformis seedlings variables increase in concentrations of proline, total soluble sugars and betaine glycine.

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Environmental controls over methanol emission from leaves

Biogeosciences Discussions ◽

10.5194/bgd-4-2593-2007 ◽

2007 ◽

Vol 4 (4) ◽

pp. 2593-2640 ◽

Cited By ~ 3

Author(s):

P. Harley ◽

J. Greenberg ◽

Ü. Niinemets ◽

A. Guenther

Keyword(s):

Stomatal Conductance ◽

Leaf Growth ◽

Dry Mass ◽

Leaf Temperature ◽

Photon Flux ◽

Photon Flux Density ◽

Emission Model ◽

Production Term ◽

Methanol Production ◽

Environmental Controls

Abstract. Methanol is found throughout the troposphere, with average concentrations second only to methane among atmospheric hydrocarbons. Proposed global methanol budgets are highly uncertain, but all agree that at least 60% of the total source arises from the terrestrial biosphere and primary emissions from plants. However, the magnitude of these emissions is also highly uncertain, and the environmental factors which control them require further elucidation. Using a temperature-controlled leaf enclosure, we measured methanol emissions from leaves of six plant species by proton transfer reaction mass spectrometry, with simultaneous measurements of leaf evapotranspiration and stomatal conductance. Rates of emission at 30°C varied from 0.3 to 38 μg g (dry mass)−1 h−1, with higher rates measured on young leaves, consistent with the production of methanol via pectin demethylation in expanding foliage. On average, emissions increased by a factor of 2.4 for each 10°C increase in leaf temperature. At constant temperature, emissions were also correlated with co-varying incident photosynthetic photon flux density and rates of stomatal conductance. The data were analyzed using the emission model developed by Niinemets and Reichstein (2003a, b), with the incorporation of a methanol production term that increased exponentially with temperature. It was concluded that control of emissions, during daytime, was shared by leaf temperature and stomatal conductance, although rates of production may also vary diurnally in response to variations in leaf growth rate in expanding leaves. The model, which generally provided reasonable simulations of the measured data during the day, significantly overestimated emissions on two sets of measurements made through the night, suggesting that production rates of methanol were reduced at night, perhaps because leaf growth was reduced or possibly through a direct effect of light on production. Although the short-term dynamics of methanol emissions can be successfully modeled only if stomatal conductance and compound solubility are taken into account, emissions on longer time scales will be determined by rates of methanol production, controls over which remain to be investigated.

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Response of in vitro Cultured Palm Oil Seedling Under Saline Condition to Elevated Carbon Dioxide and Photosynthetic Photon Flux Density

Annals of Tropical Research ◽

10.32945/atr3413.2012 ◽

2012 ◽

pp. 52-64

Author(s):

Pet Roey Pascual ◽

Krienkai Mosaleeyanon ◽

Kanokwan Romyanon ◽

Chalermpol Kirdmanee

Keyword(s):

Stomatal Conductance ◽

Net Photosynthetic Rate ◽

Elevated Co2 ◽

Photosynthetic Rate ◽

Transpiration Rate ◽

Pigment Contents ◽

Salinity Levels ◽

Oil Palms ◽

Ambient Co2

Salt stress elicits various physiological and growth responses of oil palm. A laboratory experiment was conducted to determine the responses of oil palms cultured in vitro under varying salinity levels (0, 85.5, 171.11, 342.21 and 684.43 mM NaCl) to elevated CO2 (1000 μmol CO2/mol) and PPFD (100±5 μmol m-2s-1) in terms of growth characteristics, pigment contents and photosynthetic abilities. After 14 days of culture, net photosynthetic rate (μmol CO2 m-2s-1) of oil palms across varying salinity levels was 5.33 times higher than those cultured under ambient CO, (380±100 Mmol CO2/mol) and PPFD (50±5 μmol m-2s -1). At increased net photosynthetic rate (elevated CO2 and PPFD), despite having no significant difference in pigment contents (chlorophyll a, chlorophyll b, total chlorophyll and carotenoid) between different CO2 and PPFD levels, dry weight and percent dry matter were 0.26 and 0.11 times higher, respectively, as compared to those cultured under ambient CO2 and PPFD. In the same elevated CO2 and PPFD level, across all salinity levels, stomatal conductance was 0.30 times lower than those cultured under ambient CO2 and PPFD. At reduced stomatal conductance (elevated CO2 and PPFD), transpiration rate was also reduced by 0.30 times. Thus with increased net photosynthetic rate and reduced transpiration rate, water use efficiency was increased by 7.22 times, across all salinity levels, than those cultured at ambient CO2 and PPFD. These were considered essential for NaCl produces iso-osmotic stress.

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The Influence of H2O2 Application Methods on Melon Plants Submitted to Saline Stress

Journal of Agricultural Science ◽

10.5539/jas.v11n11p245 ◽

2019 ◽

Vol 11 (11) ◽

pp. 245

Author(s):

Adriana Silva Santos ◽

Juliana Formiga Almeida ◽

Marcio Santos da Silva ◽

Jackson Silva Nóbrega ◽

Thais Batista de Queiroga ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Irrigation Water ◽

Biomass Accumulation ◽

Dry Mass ◽

Cultivated Plants ◽

Saline Stress ◽

Defense System ◽

Biotic And Abiotic Stresses ◽

Irrigation Water Salinity ◽

Number Of Leaves

The salinity in irrigation water is one of the most important causes to decline cultivated plants yield. The H2O2 application has shown efficiency as a stimulator and activator for antioxidative defense system in plants submitted to biotic and abiotic stresses. The objective of this study was to evaluate methods for hydrogen peroxide application as a strategy to minimize the effects of saline stress on melon plants. The experiment was designed in complete randomized blocks and set in 2 × 4 factorial scheme, consisting two levels for irrigation water salinity (S1 = 0.3 and S2 = 2.0 dS m-1) and four methods for hydrogen peroxide application (15 mM), (T1 = no peroxide application, T2= imbibition of seeds, T3 = at sowing, T4 = Foliar spraying), with five repetitions. It was evaluated the following variables at 58 days after transplanting: plant height, stem diameter, number of leaves, number of flowers, shoot dry mass, root dry mass and total dry mass. The results showed that salinity affected the growth, biomass accumulation and plant quality severely, with the highest losses promoted by the electrical conductivity of 2.0 dS m-1.

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