Influence of low phosphorus concentration on leaf photosynthetic characteristics and antioxidant response of rice genotypes

Abstract

Influence of different phosphorus concentrations was studied in four rice varieties (Akhanphou, MTU1010, RP BIO 226, and Swarna) differing in their tolerance to low phosphorus. There was an increase in shoot and root dry mass with the increase in phosphorus concentration. At the low phosphorus concentration at both tillering and reproductive stages, Swarna, followed by Akhanphou, recorded maximum biomass for both roots and shoots, while the minimum was observed in RP BIO 226. Reduction in photosynthetic rate, stomatal conductance, transpiration rate, and internal CO 2 concentration at low phosphorus concentrations were observed at both tillering and reproductive stages in all the genotypes. In low phosphorus, maximum photosynthetic rate was found in Swarna followed by Akhanphou. Phosphorus deficiency did not alter the maximum efficiency of PSII photochemistry, however, there was a reduction in effective PSII quantum yield, electron transport rate, and coefficient of photochemical quenching, while the coefficient of nonphotochemical quenching was higher in the low phosphorus-treated plants. Prolonged exposure to excessive energy and failure to utilize the energy in carbon-reduction cycle induced the generation of reactive oxygen species, which affected PSII as indicated by the fluorescence traits. The reduction was less severe in case of Swarna and Akhanphou. The activities of superoxide dismutase, peroxidase, and catalase increased in roots under low phosphorus concentration indicating that photoprotective mechanisms have been initiated in rice plants in response to phosphorus deficiency. Comparatively, Swarna and Akhanphou exhibited a higher biomass, higher photosynthetic rate, and better reactive oxygen species-scavenging ability which conferred tolerance under low phosphorus conditions.

Cross Tolerance to Drought and low Phosphorus Stress in Mungbean is Regulated by Improved Antioxidant Capacity, Biological N2-Fixation, and Differential Transcript Accumulation

“…We observed increased SOD, CAT, and GR activities under low P stress, relative to the control, but to a lesser degree than that observed under drought or combined stress. Similar increase in ROS production and antioxidative enzyme activity in response to low P has been reported in peanut (Arachis hypogea) (Patel et al 2020), Brassica (Chen et al 2015), and rice (Veronica et al 2017).…”

Effects of phosphorus deficiency on the absorption of mineral nutrients, photosynthetic system performance and antioxidant metabolism in Citrus grandis

“…The P-deficiency-induced reduction of photosynthesis rate was also reported in sugar beet [ 10 ], soybean [ 11 ], tobacco [ 12 ], Zizania latifolia [ 13 ], oat [ 5 ], sheepgrass [ 14 ], barley [ 15 ] and tea [ 16 ]. As result, the grain yield or production of crops was compromised by P deficiency [ 9 , 17 , 18 ]. Short-term P deprivation not only reduced P concentration but also decreased the total chlorophyll (Chl) and carotenoid content in tomato seedlings [ 19 ].…”

Phosphorus supplementation modulates nitric oxide biosynthesis and stabilizes the defence system to improve arsenic stress tolerance in mustard

“…However, supplementation with P mitigated the effects of As stress and promoted growth and photosynthetic characteristics. In Oryza sativa, PSII performance and electron transport efficiency increased with adequate P supply (Veronica et al 2017). Under inadequate P conditions, As may outcompete P for entry into the plant, causing P deficiency symptoms (Finnegan & Chen 2012) Also, As accumulation in cultivated plants is much higher in the presence of P (Bustingorri et al 2017).…”