Sulfur starvation in rice: the effect on photosynthesis, carbohydrate metabolism, and oxidative stress protective pathways

Abstract

Sulfur-deficient plants generate a lower yield and have a reduced nutritional value. The process of sulfur acquisition and assimilation play an integral role in plant metabolism, and response to sulfur deficiency involves a large number of plant constituents. Rice (Oryza sativa) is the second most consumed cereal grain, and the effects of sulfur deprivation in rice were analyzed by measuring changes in photosynthesis, carbohydrate metabolism, and antioxidants. The photosynthetic apparatus was severely affected under sulfur deficiency. The Chl content was reduced by 49% because of a general reduction of PSII and PSI and the associated light-harvesting antenna. The PSII efficiency was 31% lower at growth light, and the ability of PSI to photoreduce NADP+ was decreased by 61%. The Rubisco content was also significantly reduced in the sulfur-deprived plants. The imbalances between PSII and PSI, and between photosynthesis and carbon fixation led to a general over-reduction of the photosynthetic electron carriers (higher 1-q(P)). Chromatographic analysis showed that the level of monosaccharides was lower and starch content higher in the sulfur-deprived plants. In contrast, no changes in metabolite levels were found in the tricarboxylic acid or Calvin cycle. The level of the thiol-containing antioxidant, GSH, was 70% lower and the redox state was significantly more oxidized. These changes in GSH status led to an upregulation of the cytosolic isoforms of GSH reductase and monodehydroascorbate reductase. In addition, alternative antioxidants like flavonoids and anthocyanins were increased in the sulfur-deprived plants.

Response of Rice Yield and Soil to Sulfur Application under Water and Salinity Stresses

“…The superiority of grain and biological yields/ ha as well as harvest index by the application of sulfur may be due to its effect on reducing soil pH and improving soil structure as well as beneficial role in plant metabolism and consequently increase the yield components as previously discussed (Table 4). Similar results were observed by Lunde et al (2008).…”

Cadmium stress tolerance in crop plants

“…62 On the other hand, its deficiency regulates the chlorophyll content of leaves, N content and photosynthetic enzymes. 63,64 Plants obtain S mainly as sulfate from the soil in addition to sulfur dioxide and hydrogen sulfide from the air, and in a minor extent by leaves and through a cascade of reactions in which S gets converted into sulfide and Cys (Fig. 1).…”

RNA-Seq Analysis of Sulfur-Deprived Chlamydomonas Cells Reveals Aspects of Acclimation Critical for Cell Survival

“…Moreover, in the last 5 years, S-depleted Chlamydomonas cells have been used for microarray-based RNA abundance studies (Zhang et al, 2004;Nguyen et al, 2008), determination of metabolite profiles (Bolling and Fiehn, 2005), and sustained production of H 2 (Ghirardi et al, 2007). Many studies of S-deprived plants have also been performed (Lewandowska and Sirko, 2008;Kopriva et al, 2009); some of these studies include determinations of transcript levels and metabolite profiles (Hirai et al, 2003;Maruyama-Nakashita et al, 2003;Nikiforova et al, 2003Nikiforova et al, , 2005aNikiforova et al, , 2005bLunde et al, 2008).…”