Effects of bensulfuron-methyl residue on photosynthesis and chlorophyll fluorescence in leaves of cucumber seedlings

Abstract

A potted soil experiment was conducted to investigate the effects of bensulfuron-methyl (BSM) residue on the growth and photosynthesis of seedlings of a local cucumber variety (Xia Feng No.1). When the residue of bensulfuron-methyl in soil exceeded 50μg kg -1 , it significantly inhibited the growth of cucumber, chlorophyll content and photosynthetic capacity of cucumber. BSM treatment caused significant decreases in the biomass, chlorophyll content, net photosynthesis rate, stomatal conductance, and transpiration rate, photosystem II (PSII) maximum quantum yield, actual quantum yield, photochemical quenching coefficient, and electron transport rate in cucumber seedlings, but increased the minimal fluorescence yield and dark respiration rate. Moreover, comparisons of the patterns of absorbed light energy partitioning revealed that the fractions of excess and thermally dissipated energy increased with rising concentrations of the BSM residue, but the fraction of PSII photochemistry declined. The BSM residues caused reversible destruction in the PSII reaction centers and decreased the proportion of available excitation energy used in PSII photochemistry. The results suggested that rice or wheat fields sprayed with BSM will not be suitable for planting cucumbers in succession or rotation.

Interaction of pretilachlor with PS‐II activity of the cyanobacterium Desmonostoc muscorum PUPCCC 405.10

“…Chl a is directly related to light capture and energy conversion during photosynthesis. The loss of Chl a content under the influence of pretilachlor in this organism could lead to a net reduction in photosynthesis [29]. The results of Figures 2 and 3 further indicated that the effect of pretilachlor on photosynthetic O 2 evolution was observed within 20 min, whereas the effect on Chl a was observed after 8 h. Thus, the immediate target of pretilachlor was photosynthetic O 2 evolution rather than Chl a .…”

Early Identification of Herbicide Modes of Action by the Use of Chlorophyll Fluorescence Measurements

“…During photosynthesis, part of the solar radiation absorbed by plants is reemitted in the form of fluorescence. Therefore, by mathematical calculations, it has been established that photosynthetic processes can be monitored by measuring chlorophyll fluorescence (ChlF) signals from plants [8,9], including the impact of herbicides [10,11]. Under nonstress conditions, light energy is absorbed by chlorophyll and used in photochemical processes.…”

The residual effects of bensulfuron-methyl on growth and photosynthesis of soybean and peanut

“…Ye et al (2005) found that residual BSM inhibited root length in rape. Su et al (2016) reported that plant height, root length, and net photosynthetic rate of maize seedlings decreased with increased concentrations of BSM residue.…”