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1

Comparative analysis of essential oil composition and oil containing glands in Ocimum sanctum L. (Holy basil) under ambient and supplemental level of UV-B through gas chromatography–mass spectrometry and scanning electron microscopy

100%

Kumari R. , Agrawal S. B.

Acta Physiologiae Plantarum

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2011

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tom 33

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nr 4

EN

Field grown plants of holy basil (Ocimum sanctum L.) were treated with biologically effective supplemental ultraviolet-B (sUV-B) radiation (ambient +1.8 kJ m⁻² day⁻¹) to evaluate its effect on specialized oil glands and quantity and quality of the essential oil. The total yield of essential oil increased significantly by 42.0% after sUV-B treatment. Gas chromatography–mass spectrometry analysis showed that most important flavor compounds β-caryophyllene, germacrene-D, ethyl linoleolate, β-elemene and camphenol increased significantly after sUV-B treatment. Moreover, the level of main compound eugenol was not affected significantly. Scanning electron microscopy analysis showed turgidity of oil glands after sUV-B exposure and it was well correlated with the higher yield of essential oil. The result is of specific interest because if other parameters remain constant, sUV-B may affect the production of the essential oil in Ocimum sanctum L.

2

Alterations in metabolite profile and free radical scavenging activities of Withania somnifera leaf and root extracts under supplemental ultraviolet-B radiation

100%

Takshak S. , Agrawal S. B.

Acta Physiologiae Plantarum

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2015

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tom 37

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nr 12

EN

The effects of supplemental ultraviolet-B (s-UV-B; 3.6 kJ m⁻² day⁻¹ above ambient) radiation on plant metabolite profile and free radical scavenging activities of Withania somnifera (an indigenous medicinal plant) under field conditions were investigated. The metabolite profiles of both leaves and roots were analyzed via GC–MS. The methanolic extracts were examined for their DPPH radical- , superoxide radical-, hydrogen peroxide-, hydroxyl radical-, and nitric oxide radical scavenging activities, ferrous ion chelating activity, and reducing power. GC–MS profile of leaves revealed increment in compounds such as isophytol (138.1 %), b-stigmasterol (183.05 %), trans-squalene (233.3 %), and Withaferin A (155.0 %), while compounds such as eugenol, b-carotene, lycopene, and vitamin E were detected in s-UV-B-treated leaves only. In roots, compounds such as ledol, neophytadiene, palmitic acid, retinol, sitosteryl oleate, and campesterol registered their presence only under s-UV-B. Methanolic extracts of treated plant organs were found to be more potent as free radical scavengers (their EC₅₀ values being lower than those of control extracts). Anomalies were observed for nitric oxide radical scavenging in both leaves and roots. The present study indicates that s-UV-B alters the composition and contents of plant metabolites leading to an increase in their free radical scavenging activities. Hence, s-UV-B-treated plant organs might be more effective in combating oxidative stress as well as from a nutritional and health perspective.

3

Cultivar specific variations in morphological and biochemical characteristics of mung bean due to foliar spray of ascorbic acid under elevated ozone

100%

Chaudhary N. , Agrawal S. B.

Acta Physiologiae Plantarum

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2014

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tom 36

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nr 07

EN

Effect of exogenous application of ascorbic acid (Asc) solution was examined on the growth, photosynthetic pigments, biochemical and yield characteristics of mung bean cultivars against ozone (O₃). Experiment was performed on six mung bean cultivars in open top chambers under field conditions and Asc was applied as foliar spray prior to the exposure of ambient (AO+) and elevated (EO+) levels of O₃. Application of Asc showed increment in growth attributes as compared to plants not provided Asc (AO). However, O₃ induced the production of reactive oxygen species led to membrane damage. Reductions were depicted in lipid peroxidation, solute leakage and foliar injury % in AO+ and EO+ as compared to plants not provided with Asc. Photosynthetic pigments and ascorbic acid content along with activities of anti-oxidative enzymes (APX, CAT, GR and SOD) showed increments in AO+ and EO+ with cultivar-specific variations. Cultivars HUM1 and HUM-2 restored yield with Asc application while less response was observed in other test cultivars. Quality of the seeds was also affected by Asc treatment in the plants exposed to ambient and elevated levels of O₃. Therefore, exogenous application of Asc promotes plant’s performance by providing protection against O₃ induced oxidative stress and may be used in screening of the mung bean cultivars against O₃ phytotoxicity.

4

Effect of elevated ultraviolet-B on four tropical soybean cultivars: quantitative and qualitative aspects with special emphasis on gas exchange, chlorophyll fluorescence, biomass and yield

100%

Choudhary K. K. , Agrawal S. B.

Acta Physiologiae Plantarum

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2015

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tom 37

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nr 02

EN

Four Indian soybean cultivars (Glycine max L. cv. JS-335, JS 97-52, PK-416 and PS-1042) were grown under field conditions in suburban area of Varanasi to evaluate the varietal differences against ambient and elevated ultraviolet-B (ambient + 7.2 kJ m-2 day-1) for two consecutive years. Elevated UV-B caused negative impact on the assessed parameters with varied magnitude amongst the test cultivars. Reductions in rate of photosynthesis and stomatal conductance were observed maximum in JS-335 and minimum in PS-1042. Elevated UV-B also affected the plant abilities to utilize sunlight and increase the photoinhibitory response, which was displayed by reduced Fv/Fm in tested cultivars. Similar results were also observed for the biomass, yield and seed quality with maximum reduction in JS-335 followed by PK-416, JS 97-52 and PS-1042. Decline in the rate of photosynthesis, extra allocation of photosynthates for repairing and change in translocation pattern of solute and nutrients are mainly responsible for the deterioration in seed quality. Cumulative stress response index (CSRI) and quality response index (QRI) also revealed the sensitivity of soybean cultivars against elevated UV-B. Indexing of cultivars suggests that JS-335 was most sensitive whereas PS-1042 was resistant amongst cultivars.

5

Ambient ozone and two black gram cultivars: an assessment of amelioration by the use of ethylenediurea

100%

Singh S. , Agrawal S. B.

Acta Physiologiae Plantarum

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2011

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tom 33

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nr 6

EN

Ethylenediurea (EDU) was applied as soil drench in two Indian cultivars of black gram (Vigna mungo L. cv. Azad-1 and BHU-1) and its ameliorating effect against ozone (O₃) stress was studied on selected growth, physiological, biochemical, and yield characteristics. The study site experienced a high O₃ concentration of 41.3–59.9 ppb during the experimental period. It was found that growth parameters showed positive impact on plants treated with EDU and yield attributes were also higher than that of non-EDU-treated ones. Significant increments in ascorbic acid and protein contents were observed in EDU-treated plants as compared to control plants. Lipid peroxidation, however, showed a reverse trend in both the cultivars. Photosynthetic efficiency increased by EDU treatment as depicted by higher values for photosynthetic rate (Ps) and Fv/Fm ratio. EDU-treated plants had more efficient antioxidant enzyme defense system with higher SOD and POX activities. Both the cultivars showed differential response against O₃ and cultivar BHU-1 proved to be resistant as compared to Azad-1. This investigation proves the usefulness of EDU as a biomonitoring tool against O₃ for the remote areas having higher concentrations of O₃ and problem of frequent electricity failure.

6

Effects of supplemental ultraviolet-B radiation on growth and physiology of Acorus calamus L.[sweet flag]

80%

Kumari R. , Singh S. , Agrawal S. B.

Acta Biologica Cracoviensia. Series Botanica

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2009

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tom 51

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nr 2

19-27

EN

Increased UV-B radiation due to depletion of stratospheric ozone has potentially harmful effects on plant growth and development. The present study uses a field experiment to examine the effect of long-term supplemental UVB radiation at two intensities (+1.8 and +3.6 kJ m-2 d-1 above ambient) on the growth and physiology of the medicinal plant Acorus calamus L. (sweet flag). Plant height and leaf area were inhibited in a dose-dependent manner, with greater inhibition at the higher dose. At the lower dose the net photosynthetic rate increased, with an increase in stomatal conductance and water use efficiency. Stimulation of physiological functions in plants under the lower dose resulted in increased biomass production. At the higher dose, total chlorophyll content showed no marked variation, whereas carotenoids and UV-B-screening pigment flavonoids increased significantly after treatment. Increased flavonoid content under lower exposure correlates well with higher activity of phenylalanine ammonia lyase, a key enzyme of flavonoid biosynthesis. This study clearly showed that the lower dose of supplemental UV-B promoted rhizome growth in A. calamus, perhaps due to improved photosynthesis. Plant defense was stronger under the lower dose

7

Intraspecific rsponses of six cultivars of wheat (Triticum aestivum L.) to supplemental ultraviolet-B radiation under field conditions

80%

Singh M. , Singh S. , Agrawal S. B.

Acta Physiologiae Plantarum

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2012

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tom 34

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nr 1

EN

The solar ultraviolet-B (UV-B) background level is often high and posing an environmental challenge in most of the tropical region of the world, including India. This prompted the present study to investigate the effects of supplemental UV-B (sUV-B) radiation (ambient + 7.2 kJ m⁻² day⁻¹) on various growth, physiological and biochemical characteristics of six locally grown cultivars of wheat (Triticum aestivum L.). Plants being sessile protect themselves from the harmful UV-B radiation by synthesizing flavonoids to screen UV-B and also by inducing antioxidant defence system. sUV-B radiation negatively affected the growth of wheat seedlings but the response varied amongst the cultivars. Leaf injury was maximum in cv. PBW154 and minimum in HD2824. Values of sensitivity index also revealed that HD2824 was least sensitive to sUV-B, while PBW154 was most sensitive. All the assessed biochemical parameters corresponded well with the sensitivity index of different cultivars of wheat.

8

Impact of ultraviolet-B radiation on photosynthetic capacity, antioxidative potential and metabolites in Solanum tuberosum L. under varying lavels of soil NPK

80%

Singh S. , Agrawal M. , Agrawal S. B.

Acta Physiologiae Plantarum

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2014

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tom 36

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nr 06

EN

The impact of supplemental ultraviolet-B (sUV-B; 280–315 nm; +7.2 kJ m⁻² d⁻¹) radiation was studied on various physiological parameters, antioxidative potential and metabolites of Solanum tuberosum L. cv. Kufri Badshah plants under varying levels of soil NPK. The N, P and K treatments were: the recommended dose of N, P and K; 1.5 times the recommended dose of N, P and K; 1.5 times the recommended dose of N and 1.5 times the recommended dose of K. The recommended NPK level provided maximum protection to photosynthetic assimilation under sUV-B radiation, while stomatal conductance was best at 1.5 times the recommended NPK. Carbon dioxide assimilation declined maximally at 1.5 times the recommended N/K under sUV-B radiation. Plants grown at the recommended NPK and 1.5 times the recommended NPK levels showed higher superoxide dismutase, peroxidase and ascorbate peroxidase activities under sUV-B radiation compared to 1.5 times the recommended N/K levels. sUV-B significantly increased total phenolics and flavonoids in plants at the recommended and 1.5 times the recommended NPK, while flavonoids declined at 1.5 times the recommended N. This study clearly showed that NPK amendment provided maximum protection to photosynthetic assimilation of potato plants under sUV-B radiation, activating the antioxidative defense system as well as flavonoids. NPK at 1.5 times the recommended dose, however, did not cause any additional benefit to photosynthetic carbon fixation; hence the recommended dose of NPK is found to be the best suited dose of fertilizer under ambient as well as sUV-B regime.

9

Responses of Zea mays L. cultivars ‘Buland’ and ‘Prakash’ to an antiozonant ethylene diurea grown under ambient and elevated levels of ozone

70%

Singh A. A. , Chaurasia M. , Gupta V. , Agrawal M. , Agrawal S. B.

Acta Physiologiae Plantarum

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2018

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tom 40

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nr 05