The poor productivity and local confinement of indigenous aromatic rice varieties are mostly due to their susceptibility to salinity/drought/abscisic acid (ABA)-mediated abiotic stresses. It is thus essential to study the effects of several stress factors on their physiological parameters so as to improve their tolerance mechanism and enhance their global demand. Previously, we studied the effect of salinity stress on the physiological and molecular responses of the common aromatic rice Gobindobhog. The objective of this study was to understand the influence of exogenous ABA on some biochemical parameters in Gobindobhog, and comparison with those from non-aromatic M-1-48 and Nonabokra rice. The highest endogenous hydrogen peroxide content and membrane lipid peroxidation (increased malondialdehyde and lipoxygenase activity) were found in ABA-treated Gobindobhog leaves. While the catalase activity was down regulated the most in ABA-treated Gobindobhog leaves, the guaiacol peroxidase activity was induced maximally, indicating the protective role of peroxidase rather than catalase, during ABA-induced oxidative damages. The antioxidant, anthocyanin, showed the highest level in ABA-treated Nonabokra. Enhanced cysteine, following ABA exposure and the highest levels of reducing sugars, total amino acids, proline, and polyamines (putrescine and spermidine) recorded in Gobindobhog, probably served to shield from ABA-induced stress injuries, whereas the spermine levels were comparable in ABA-treated Nonabokra and Gobindobhog. The aroma content, intensified after ABA treatment, was markedly noted in Gobindobhog. Thus, the systematic examination of ABA-mediated stress revealed the most prominent oxidative damages in Gobindobhog, even higher than M-1-48, with a concomitant enhancement in peroxidase system and particularly osmolyte or polyamine levels to ensure its sustenance. © Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków 2009.

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D N SENGUPTA

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

Acta Physiologiae Plantarum

Extensive investigation into plant response and adaptation to diverse osmotic stresses like high salt/dehydration/low temperature, involving a broad spectrum of cellular physiological and biochemical changes, is essential to unravel intrinsic mechanism to mitigate against such stresses. In our previous communications, we conducted biochemical analyses of indica rice varieties, subjected to exogenous salt/abscisic acid-mediated oxidative stress. The aim of this study was to compare differential biochemical responses of the salt-sensitive (IR-29), salt-tolerant (Pokkali) and aromatic (Pusa Basmati or PB) rice varieties during polyethylene glycol (PEG)-induced dehydration stress. The greater susceptibility of IR-29 and PB, to water scarcity, was reflected by the higher toxic Na+ and putrescine accumulation, considerable decrease in (reduced/oxidized) glutathione, maximal increment in protease activity and greater downregulation of nitrate reductase activity. On the other hand, Pokkali appeared to suffer lesser damages as evidenced from much lower endogenous Na+ but higher K+, Ca2+ and Mg2+ accumulation, registering the highest levels of osmolytes like glycinebetaine and higher polyamines (spermidine and spermine) accounting to improved relative water content, higher (reduced/oxidized) glutathione, maximal induction of the enzyme phenylalanine ammonia-lyase and practically unhindered nitrate reductase activity, following PEG treatment. The highest induction of sugars and proline in IR-29 and PB probably played the osmoprotective/antioxidative functions, enabling to a certain extent to heighten their lipoxygenase inhibition or H2O2 scavenging potential, more than Pokkali, to ward off oxidative damages and sustain survival under critical dehydrated situations. Thus, the salt-tolerant Pokkali also showed prominent dehydration-tolerance properties, whereas the aromatic rice PB, almost identical in their biochemical responses to IR-29, showed greater sensitivity to PEG-mediated water deficit. © Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków 2009.

Comparative analysis of some biochemical responses of three indica rice varieties during polyethylene glycol-mediated water stress exhibits distinct varietal differences

Effects of exogenous abscisic acid on some physiological responses in a popular aromatic indica rice compared with those from two traditional non-aromatic indica rice cultivars

In an attempt to understand the molecular basis of salt-stress response in the aromatic rice Gobindobhog, a comprehensive analysis encompassing physiological or biochemical assays and gene expression studies under high salt (200 mM NaCl) supply regimes were initiated and compared with a salt-sensitive (M-1-48) and salt-tolerant (Nonabokra) rice. The detrimental effects of salinity stress were the most pronounced in Gobindobhog, as reflected by the maximally increased root to shoot ratio, the highest chlorophyll degeneration, the highest foliar concentration of Na+ ions and peroxide content, with their maximum increment after salt treatment. The amplification of oxidative damages was further stimulated by the accumulation of putrescine and lipid peroxidation-derived toxic degradation products (increased malondialdehyde and lipoxygenase activity), which were comparable in M-1-48 and Gobindobhog. Antioxidants like anthocyanin and particularly cysteine and the osmolytes like reducing sugar, proline and polyamines (spermidine and spermine) showed the highest level in Nonabokra. While the inhibition of catalase activity occurred in all the varieties following salt-stress, the maximum induction in guaiacol peroxidase activity, elevated cysteine and proline levels in Gobindobhog probably constituted the detoxification mechanism obligatory for its survival. Intensification of the aroma content with salt treatment was markedly noted in Gobindobhog. A very low abundance of Rab16A/SamDC transcript and the corresponding proteins were observed both in M-1-48 and Gobindobhog, induced only after salt-stress, whereas they were constitutively expressed in Nonabokra. Thus, our data reflect Gobindobhog as a salt-sensitive cultivar, susceptible to high-stress-induced growth-inhibition, ion imbalances, membrane/oxidative damages with lower expression of stress-tolerant genes. © 2008 Springer-Verlag.

Plant Cell Reports

Comparative physiological and molecular responses of a common aromatic indica rice cultivar to high salinity with non-aromatic indica rice cultivars

Czech Journal of Genetics and Plant Breeding

10.17221/cjgpb-3-4

Rice Genetics Collection Rice Genetics III

High-molecular weight proteins associated with response of rice to various abiotic stresses

Journal of Experimental Botany

Duplicate maize 13-lipoxygenase genes are differentially regulated by circadian rhythm, cold stress, wounding, pathogen infection, and hormonal treatments

Journal	Data powered by TypesetActa Physiologiae Plantarum
Publisher	Data powered by TypesetSPRINGER HEIDELBERG
ISSN	0137-5881