CO2 exchange, primary photochemical reactions and enzymes of photosynthetic carbon reduction cycle in Brassica pods during water stress and recovery

Title:

CO2 exchange, primary photochemical reactions and enzymes of photosynthetic carbon reduction cycle in Brassica pods during water stress and recovery

Creator:

Dua, A., Talwar, G., Singal, H.R., and Singh, R.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:191298a1-c1b6-4aaf-90b4-f84b2fde50c0
uuid:191298a1-c1b6-4aaf-90b4-f84b2fde50c0
urnnbn:urn:nbn:cz:aba007-000fkj

Type:

model:internalpart and TEXT

Format:

print

Description:

Under a moderate water stress (pod water potential, Ψ№, - 1.5 MPa), induced by stopping irrigation for 3 d, the net photosynthetic rate (PN) decreased to 50 %, transpiration rate (£) to 85 %, stomatal conductance to 65 % and chlorophyll (Chi) content to 82 %, while the activities of photosystems (PS) and of some enzymes of the photosynthetic carbon reduction cycle (NAD- and NADP-glyceraldehyde-3-P dehydrogenases, aldolase) were almost without changes. The exceptions were ribulose-5-P kinase and 3-phosphoglycerate kinase, the activities of which were reduced to 55 and 79 %, respectively. Under a severe water stress (5 d without irrigation, VPW -2.1 MPa) all the above characteristics were strongly reduced (PN to 0.5 %, E to 57 %, PS1 to 62 %, PS2 to 37 %, enzyme activities to 48-68 %), but after rehydration the initial activities were restored. The reduction of PN in pods at a moderate water stress is probably related to the decline in activities of 3-phosphoglycerate kinase and ribulose-5-P kinase, while under a severe stress, when PN is lowered almost to zero, the decline in gs and electron transport activities is very important.

Language:

Multiple languages

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Coverage:

261-268 and 103-110

Source:

Photosynthetica | 1994 Volume:30 | Number:2

Harvested from:

CDK

Metadata only:

false