Mitigation of Drought Damages by Exogenous Chitosan and Yeast Extract with Modulating the Photosynthetic Pigments, Antioxidant Defense System and Improving the Productivity of Garlic Plants

Garlic is an important vegetable in terms of its economic value and also as a medicinal plant. In this study, chitosan (300 mM) and yeast extract (8 g/L) were used individually or in combination to improve the yields of garlic plants under drought conditions (i.e., 75% and 50% of the water they would normally receive from irrigation) for two seasons. Significant decreases in numbers of leaves per plant and plant height, plant dry weight, relative water content, and chlorophyll a and b concentrations were found in stressed garlic plants in both seasons. The greatest reductions in these characters were recorded in plants that received only 50% of the normal irrigation in both seasons. Levels of hydrogen peroxide, products of lipid peroxidation such as malondialdehyde, and superoxide, as well as percentages of electrolyte leakage, were elevated considerably and were signals of oxidative damage. The application of the yeast extract (8 g/L) or chitosan (300 mM) individually or in combination led to a remarkable increase in the most studied characters of the stressed garlic plants. The combination of yeast extract (8 g/L) plus chitosan (300 mM) led to increase plant height (44%), ascorbic acid levels (30.2%), and relative water content (36.8%), as well as the chlorophyll a (50.7%) and b concentrations (79%), regulated the proline content and levels of antioxidant enzymes in stressed garlic plants that received 75% of the normal irrigation, and this decreased the signs of oxidative stress (i.e., percentage of electrolyte leakage and levels of malondialdehyde, hydrogen peroxide, and superoxide).

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Beneficial Effects of Biochar and Chitosan on Antioxidative Capacity, Osmolytes Accumulation, and Anatomical Characters of Water-Stressed Barley Plants

Agronomy ◽

10.3390/agronomy10050630 ◽

2020 ◽

Vol 10 (5) ◽

pp. 630 ◽

Cited By ~ 5

Author(s):

Yaser Hafez ◽

Kotb Attia ◽

Salman Alamery ◽

Abdelhalim Ghazy ◽

Abdullah Al-Doss ◽

...

Keyword(s):

Lipid Peroxidation ◽

Drought Stress ◽

Water Content ◽

Plant Height ◽

Electrolyte Leakage ◽

Relative Water Content ◽

Relative Water ◽

Number Of Leaves ◽

The Impact ◽

Chlorophyll Concentrations

The impact of biochar and chitosan on barley plants under drought stress conditions was investigated during two field experiments. Our results confirmed that drought stress negatively affected morphological and physiological growth traits of barley plants such as plant height, number of leaves, chlorophyll concentrations, and relative water content. However, electrolyte leakage (EL%), lipid peroxidation (MDA), soluble sugars, sucrose and starch contents significantly increased as a response to drought stress. Additionally, 1000 grain weight, grains yield ha−1 and biological yield significantly decreased in stressed barley plants, also anatomical traits such as upper epidermis, lower epidermis, lamina, and mesophyll tissue thickness as well as vascular bundle diameter of flag leaves significantly decreased compared with control. The use of biochar and chitosan led to significant increases in plant height, number of leaves, and chlorophyll concentrations as well as relative water content; nevertheless these treatments led to significant decreases in electrolyte leakage (EL%) and lipid peroxidation (MDA) in the stressed plants. Moreover, anatomical and yield characters of stressed barley plants were improved with application of biochar and chitosan. The results proved the significance of biochar and chitosan in alleviating the damaging impacts of drought on barley plants.

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Ameliorative role of Silicon on Osmoprotectants, Antioxidant Enzymes and Growth of Maize Grown Under Alkaline Stress

10.21203/rs.3.rs-569172/v1 ◽

2021 ◽

Author(s):

Sriramachandrasekharan Malayappa venkataraman ◽

Gokula Priya Natarajan ◽

Manivannan Rengarajan ◽

Prakash Muthu Arjuna Samy

Keyword(s):

Antioxidant Enzymes ◽

Water Content ◽

Electrolyte Leakage ◽

Relative Water Content ◽

Dry Weight ◽

Water Soluble ◽

Maximum Effect ◽

Antioxidant Systems ◽

Alkaline Stress ◽

Relative Water

Abstract Purpose Maize is grown under a wide spectrum of soil and climatic conditions. Maize is moderately sensitive to salt stress and response of maize under alkaline stress is scanty. Further, silicon is known to protect crops from abiotic stress. Hence, a pot experiment was conducted to study the mechanism on the effect of silicon on maize grown in alkaline stress Methods Maize CO 8 was grown in soil treated with four levels of alkaline stress (0, 25, 50, 75 mM) created through addition of sodium carbonate and three levels of silicon (0,100 and 150 kg ha− 1) applied to root through sodium meta silicate. The experiment was conducted in factorial CRD with three replications. Results Alkaline stress at graded levels caused reduction in growth (5 to 16%), dry weight (28 to 59%) and relative water content (5 to 23%). But electrolyte leakage (6 to 49%), proline (26 to 62%), phenol (8 to 44%), protein (6 to 19%), anti-oxidant systems viz., peroxidase (30 to 52%), SOD (4 to 16%) and catalase activities (32 to 127%) increased with increase in alkaline stress level. Soil application of silicon at different levels improved growth ( 5 to 10%) and dry weight (17 to 30%) of maize, relative water content (6 to 12%) and antioxidant enzymes ( 25 to 52%), water soluble protein ( 7 to10%), phenol ( 10 to 18%) while reduced electrolyte leakage( 15 to 25%) and proline( 17 to 29%). Conclusions It is evident from the study that root supplementation of silicon improved the growth and dry weight of maize crop grown in alkaline stress soil through its action on antioxidant systems and maximum effect was evident with 150 kg Si/ha

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Study some of Morphological and Physiological Traits of Kurrajong Brachychiton populneus (Schott & Endl.) Seedlings Planted under Water Stress Conditions

Basrah Journal of Agricultural Sciences ◽

10.37077/25200860.2020.33.1.16 ◽

2020 ◽

Vol 33 (1) ◽

pp. 213-220

Author(s):

Shaima A. Karim ◽

Sirwa A. Qadir ◽

Halmat A. Sabr

Keyword(s):

Drought Stress ◽

Water Content ◽

Chlorophyll A ◽

Relative Water Content ◽

Photosynthetic Pigment ◽

Total Content ◽

Dry Weight ◽

Severe Drought ◽

Shoot Height ◽

Relative Water

In this study, Brachychiton populneus seedlings were subjected to drought stress for 90 Days and physiological and morphological characters analyzed to determine their response to water deficit. The growth characters including, height and diameter of shoots, the dry weight of shoots and roots as well as photosynthetic pigment and the leaves content of relative water content were measured to evaluate the effects of drought in the physiological growth of plant. The lowest means; 59 cm and 8 mm of shoot height and diameter respectively were recorded at 30% of water holding capacity of soil (WHC). Drought treated seedlings at both 60% and 30% WHC had lower dry weight of shoots; 9.54 and 8.24 g plant-1 respectively compared to the control. Consequently, the increase of drought conditions led to enhancement the growth of roots and roots to shoots ratio. The highest increase in the dry weight of roots and roots to shoots ratio were25.96 g plant-1 and 3.19 recorded under severe drought stress condition. Lowest amount of chlorophyll a; 2.94 mg g-1 F W recorded under 30% SWHC. It is found also the total content of chlorophyll in the leaves decreased significantly; 5.86 and 7.88 mg g-1 F W under both levels. While the highest ratio of chlorophyll a: b was 1.59 recorded at 60% SWHC. However, the lowest leave relative water content LRWC%; 86% was recorded under 30% SWHC. These findings may explain the characters of the early growth and physiological responses of, Brachychiton populneus to dehydration and facilitate the selection of drought-resistant tree families.

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Pengaruh Konsentrasi Biostimulan Berbahan Aktif Bacillius subtilis dan Waktu Pemberian Terhadap Pertumbuhan dan Produksi Bawang Merah (Allium ascalonicum L.)

JURNAL BUDIDAYA PERTANIAN ◽

10.30598/jbdp.2020.16.2.132 ◽

2020 ◽

Vol 16 (2) ◽

pp. 132-139

Author(s):

Anggia Hattalaibessy ◽

Imelda J Lawalatta ◽

Henry Kesaulya

Keyword(s):

Water Content ◽

Plant Height ◽

Relative Water Content ◽

Leaf Size ◽

Dry Weight ◽

Growth And Yield ◽

Vegetable Production ◽

Weight Percentage ◽

Relative Water ◽

Administration Time

Shallot production is highly dependent on inorganic fertilizers because it provides high yields, but it turns out that it causes a lot of environmental problems. Organic and biological fertilizers containing bio stimulants have been developed as a more environmentally friendly alternative for vegetable production including shallot. This study is aimed at acquiring the right bio stimulant concentration and administration time to the growth and yield of shallot, as indicated by plant height, leaf size, biomass weight, bulb weight, total bulb weight percentage, leaf relative water content and the analysis of chlorophyll content. This research was arranged as a factorial experiment organized in a Randomized Block with two factors, i.e., bio stimulant concentration and administration time. Results of this studies showed that the combination of the bio stimulant concentration of 3.5 mL/L with administration time of every 7 day was the best combination of treatments and could increase plant height, leaf number, tiller number, bulb weight, total bulb weight percentage, bulb number, canopy dry weight, relative water content and leaf chlorophyll. Keywords: biostimulant, concentration, growth, shallot, yield ABSTRAK Produksi bawang merah sangat tergantung pada pupuk anorganik karena dapat memberikan hasil yang tinggi; tetapi ini ternyata berdampak menimbulkan masalah kerusakan lingkungan. Pupuk organik dan hayati yang mengandung biostimulan telah mulai dikembangkan sebagai alternatif yang lebih ramah lingkungan untuk produksi sayuran, termasuk bawang merah. Penelitian ini bertujuan untuk mendapatkan tingkat konsentrasi biostimulan dengan waktu pemberian yang tepat terhadap pertumbuhan dan produksi bawang merah, yang ditunjukkan oleh tinggi tanaman, jumlah daun, jumlah anakan, berat biomasa, berat umbi, presentase berat total umbi, jumlah umbi, berat kering tajuk, analisis kadar air relatif daun dan analisis kandungan klorofil daun. Penelitian ini dilakukan sebagai percobaan faktorial yang disusun dalam Rancangan Acak Kelompok dengan 2 faktor. Kedua faktor tersbut adalah tingkat konsentrasi biostimulan dan waktu pemberian. Hasil penelitian menunjukan bahwa konbinasi antara konsentrasi biostimulan 3,5 mL/L dengan waktu pemberian 7 hari sekali merupakan kombinasi perlakuan terbaik dan dapat meningkatkan tinggi tanaman, jumlah daun, jumlah anakan, berat umbi, presentase berat total umbi, jumlah umbi, berat kering tajuk, kandungan air relatif dan klorofil daun. Kata kunci: bawang merah, biostimulan, konsentrasi, pertumbuhan, produksi.

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Ameliorative Effect of CaCl2 on Growth, Membrane Permeability and Nutrient Uptake in Oryza sativa Grown at High NaCl Salinity

International Letters of Natural Sciences ◽

10.18052/www.scipress.com/ilns.8.14 ◽

2014 ◽

Vol 8 ◽

pp. 14-22 ◽

Cited By ~ 2

Author(s):

D. Anbu ◽

S. Sivasankaramoorthy

Keyword(s):

Oryza Sativa ◽

Water Content ◽

Membrane Permeability ◽

Calcium Chloride ◽

Nutrient Solution ◽

Relative Water Content ◽

Dry Weight ◽

Physiological Variables ◽

Relative Water ◽

Ameliorative Effect

A pot culture was carried out with Oryza sativa L. vari-Co-39, to investigate the effects of supplementary calcium chloride on plants grown at NaCl (50mM) concentration. Treatments were: (1) Control: nutrient solution alone (C); (2) nutrient solution plus 50mM sodium chloride (NaCl); (3) nutrient solution plus 10mM calcium chloride (CaCl2); (4) nutrient solution plus 15mM calcium chloride (CaCl2); (5) nutrient solution and 50 mM NaCl plus supplementary 10 mM CaCl2 (NaCl + CaCl2); and (6) 50 mM NaCl plus additional mixture of 15 mM CaCl2 in nutrient solution (NaCl + CaCl2). The plants grown under salt stress produced low dry weight and relative water content than those grown in standard nutrient solution and in CaCl2 alone. Supplemental calcium chloride added to nutrient solution containing salt significantly improved growth and relative water content. Membrane permeability increased with high NaCl application and these increases in root membrane permeability were decreased with supplementary Ca. The concentration of chloride (Cl) increases highly for all treatments. Sodium (Na) concentration in plant tissues increased in both shoots and roots at high NaCl treatment. Application of supplementary Ca lowered Na concentration. Concentrations of Ca. K and N were at deficient ranges in the plants grown at high NaCl levels and these deficiencies were corrected by supplementary Ca. The ameliorating effect of Ca on growth and physiological variables could reduce the negative effect of salinity of Oryza sativa L., plants.

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In vitro screening of rice genotypes using polyethylene glycol under drought stress

Progressive Agriculture ◽

10.3329/pa.v27i2.29321 ◽

2016 ◽

Vol 27 (2) ◽

pp. 128-135 ◽

Cited By ~ 1

Author(s):

J Akte ◽

S Yasmin ◽

MJH Bhuiyan ◽

F Khatun ◽

J Roy ◽

...

Keyword(s):

Water Stress ◽

Drought Stress ◽

Water Content ◽

Relative Water Content ◽

Dry Weight ◽

Proline Accumulation ◽

Shoot Length ◽

Fresh Weight ◽

Relative Water

Five rice varieties viz. Binadhan-4, Binadhan-5, Binadhan-6, Binadhan-10 and Iratom-24 were evaluated in vitro under different water stress conditions. Several parameters such as germination percentage, shoot length, root length, shoot-root ratio, fresh weight, dry weight, turgid weight, relative water content and proline accumulation were studied. Drought condition was created by MS medium supplemented with five treatments of PEG, with a control such as 0%, 1%, 2%, 3% and 4% of PEG. The highest germination (100%) was found in the variety Binadhan-10 under low water stress conditions induced by 1% PEG. Similarly, the highest percentage of germination was found in all varieties under control condition (0% PEG). The lowest percentage of germination was obtained in the variety Iratom-24. But under severe stress (4% PEG), the highest percentage of germination was found only in the variety Binadhan-10. Moreover, the variety Binadhan-10 was found to be the best at 4% PEG for shoot length, root length, shoot-root ratio, relative water content and also the best at 1% PEG for fresh weight, dry weight, turgid weight. Water stress decreased relative water content and increased proline accumulation in rice. The highest relative water content was recorded in the variety Binadhan-10 and the lowest value recorded in the variety Binadhan-5. The highest proline content was obtained from the binadhan-6 at the highest treatment (4% PEG). Binadhan-10 showed the best performance almost in all the parameters under drought stress because of its own nature of tolerancy.Progressive Agriculture 27 (2): 128-135, 2016

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Biochemical metabolism of two cultivars of cowpea treated with 24-Epibrassinolide and subjected to saline stress

Australian Journal of Crop Science ◽

10.21475/ajcs.19.13.03.p1390 ◽

2019 ◽

Vol 13 ((03) 2019) ◽

pp. 444-451

Author(s):

Kerolém Prícila Sousa Cardoso ◽

Susana Silva Conceição ◽

Ana Ecídia de Araújo Brito ◽

Jéssica Taynara da Silva Martins ◽

Liliane Corrêa Machado ◽

...

Keyword(s):

Amino Acids ◽

Nitrate Reductase ◽

Water Content ◽

Glycine Betaine ◽

Electrolyte Leakage ◽

Relative Water Content ◽

Reductase Activity ◽

Soluble Proteins ◽

Saline Stress ◽

Relative Water

We aimed to evaluate the changes in biochemical metabolism generated by salt stress and to investigate the effect of brassinosteroids in mitigating of this stress on two cultivars of Vigna unguiculata L. We used a completely randomized experimental design in a 2 x 3 x 3 factorial scheme, using two cultivars of cowpea (BRS Guariba and BR3 Tracuateua - moderately tolerant and sensitive to salinity, respectively), three concentrations of brassinosteroids (0, 0.2 and 0.4 μM Br) and three concentrations of NaCl (0 , 50 and 100 mM NaCl), with four replicates. The following evaluations were carried out: relative water content, electrolyte leakage, nitrate levels, nitrate reductase activity, free ammonium, total soluble amino acids, soluble proteins, glycine betaine and proline. The results showed that salinity at 100 mM affected the nitrate reductase enzyme activity, the relative water content, total soluble amino acids and soluble proteins for cultivars BR3 Tracuateua, and BRS Guariba, but the 24-epibrassinolid attenuated the effects of salinity for these variables. The concentration of 0.2 μM of Br increased 55% and 20% in proline and glycine betaine contents, respectively, in both of cultivars. The plants under stress saline and 0.2 mM of 24-epibrassinolid, presented 42% and 58% reductions in electrolyte leakage of BR3 Tracuateua and BRS Guariba cultivars, respectively. The concentrations of ammonium were slightly varied. Therefore, the application of 0.2 μM of 24-epibrassinolid caused a greater acclimatization of the cultivars, being the BR3 Tracuateua (sensitive to salt) cultivar more expressive in most treatments.

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Effect of Salt-Tolerant Bacterial Inoculations on Rice Seedlings Differing in Salt-Tolerance under Saline Soil Conditions

Agronomy ◽

10.3390/agronomy10071030 ◽

2020 ◽

Vol 10 (7) ◽

pp. 1030 ◽

Cited By ~ 1

Author(s):

Rakiba Shultana ◽

Ali Tan Kee Zuan ◽

Mohd Rafii Yusop ◽

Halimi Mohd Saud ◽

Arolu Fatai Ayanda

Keyword(s):

Salt Tolerance ◽

Plant Growth ◽

Water Content ◽

Electrolyte Leakage ◽

Relative Water Content ◽

Rice Variety ◽

Salt Tolerant ◽

Relative Water ◽

Plant Growth Promoting ◽

Growth Promoting

Salt-tolerant plant growth-promoting rhizobacteria (PGPR) could be an alternative to alleviate salinity problems in rice plants grown in the coastal areas. This study was conducted to isolate and characterize salt-tolerant PGPR and observe their effects on the physiological and biochemical properties of rice plants grown under non-saline and saline glasshouse conditions. Three strains were selected based on their salt-tolerance and plant growth-promoting properties under in vitro saline conditions. These strains were identified as Bacillus tequilensis (UPMRB9), Bacillus aryabhattai (UPMRE6), and Providencia stuartii (UPMRG1) using a 16S rRNA technique. The selected strains were inoculated to three different rice varieties, namely BRRI dhan67 (salt-tolerant), Putra-1 (moderate salt-tolerant), and MR297 (salt-susceptible) under glasshouse conditions. Results showed that the MR297 rice variety inoculated with UPMRB9 produced the highest total chlorophyll content, with an increment of 28%, and lowest electrolyte leakage of 92%. The Putra-1 rice variety also showed a 156% total dry matter increase with the inoculation of this bacterial strain. The highest increase of relative water content and reduction of Na/K ratio were found upon inoculation of UPMRE6 and UPMRB9, respectively. The biggest significant effects of these bacterial inoculations were on relative water content, electrolyte leakage, and the Na/K ratio of the BRRI dhan67 rice variety under saline conditions, suggesting a synergistic effect on the mechanisms of plant salt-tolerance. This study has shown that the application of locally-isolated salt-tolerant PGPR strains could be an effective long-term and sustainable solution for rice cultivation in the coastal areas, which are affected by global climate change.

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Increased drought resistance of black locust seedlings via pretreatment of seeds with paclobutrazol

Canadian Journal of Forest Research ◽

10.1139/x93-315 ◽

1993 ◽

Vol 23 (12) ◽

pp. 2548-2551 ◽

Cited By ~ 2

Author(s):

Shen Hui-Juan ◽

Zeng Bin

Keyword(s):

Osmotic Stress ◽

Water Content ◽

Drought Resistance ◽

Electrolyte Leakage ◽

Relative Water Content ◽

Black Locust ◽

Cellular Stress ◽

Relative Water

The drought resistance of black locust (Robiniapseudoacacia L.) seedlings was increased by pretreatment of seeds with 250 ppm paclobutrazol. Treated seeds produced seedlings with thick roots and higher root/shoot ratios. During osmotic stress, treated plants displayed greater relative water content, lower electrolyte leakage, and fewer symptoms of wilt when compared with untreated black locust seedlings. Paclobutrazol-treated seedlings accumulated more proline than untreated seedlings in response to drought. However, osmotically induced accumulation of putrescine, a possible marker of cellular stress, was reduced in the treated plants.

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Etanol e ácido cítrico aumentam a longevidade de gérberas cv. Mistique

Ornamental Horticulture ◽

10.14295/oh.v25i2.2009 ◽

2019 ◽

Vol 25 (2) ◽

pp. 109-118

Author(s):

Rúbia Kécia Marins Maia ◽

Edivan Amaro da Silva ◽

Rafael Mateus Alves ◽

Maria Aparecida Dos Santos Morais ◽

Marcos Ribeiro da Silva Vieira ◽

...

Keyword(s):

Citric Acid ◽

Water Content ◽

Electrolyte Leakage ◽

Relative Water Content ◽

Distilled Water ◽

Cut Flowers ◽

Water Control ◽

Relative Water ◽

Stem Bending ◽

Application Methods

Ethanol and citric acid can increase longevity in some cut flowers. However, its use must be extremely careful, with application methods and specific concentrations for each type of cut flower. Thus, the objective was to examine the physico-chemical and physiological changes in Gerbera cv. Mistique cut flowers treated with ethanol (Et) and/or citric acid (CA). Stem were selected and standardized to a length of 35 cm and maintained at 20 ± 2 ºC and RH 65 ± 2%, under continuous lighting. The flowers were subjected to two application methods (pulsing for 48 h and maintenance), using different concentrations of Et (4%, 6%, and 8%) and/or CA (100 and 200 mg L-1) and distilled water (control). A visual assessment and analyses of longevity, stem bending, fresh mass, relative water content, electrolyte leakage, and peroxidase and polyphenol oxidase enzyme activities were performed at every two days. The Et (4%) + CA (100 mg L-1) solution provided the greatest longevity, regardless of the application method. These results were the basis for a third experiment, in which the stems were immersed in pulsing solutions of Et (4%) and/or CA (100 mg L-1) and distilled water (control). The Gerbera flowers under Et + CA solution showed lower fresh mass loss and electrolyte leakage, higher relative water content and a slower increase in polyphenol oxidase and peroxidase activities. This allowed for delayed stem bending and better appearance, resulting in greater longevity compared to the other solutions.

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