Work

Ultrastructural alterations in mesophyll and bundle sheath chloroplasts of two maize cultivars in response to chilling at high irradiance

Year: 2007
Type: article
Abstract: Maize (Zea mays L.) seedlings of two cultivars (cv. Bastion adapted to W. Europe, and cv. Batan 8686 adapted to the highlands of Mexico), raised in a glasshouse (19-25 °C), were transferred to 4.5 or 9 °C at photon flux density (PPFD) of 950 µmol m-2 s-1 with 10-h photoperiod for 58 h and then allowed to recover at 22 °C for 16 h (14 h dark and 2 h at PPFD of 180 µmol m-2 s-1). The ultrastructural responses after 4 h or 26 h at 4.5 °C were the disappearance of starch grains in the bundle sheath chloroplasts and the contraction of intrathylakoid spaces in stromal thylakoids of the mesophyll chloroplasts. At this time, bundle sheath chloroplasts of cv. Batan 8686 formed peripheral reticulum. Prolonged stress at 4.5 °C (50 h) caused plastid swelling and the dilation of intrathylakoid spaces, mainly in mesophyll chloroplasts. Bundle sheath chloroplasts of cv. Batan 8686 seedlings appeared well preserved in shape and structure. Batan 8686 had also higher net photosynthetic rates during chilling and recovery than Bastion. Extended leaf photobleaching developed during the recovery period after chilling at 4.5 °C. This was associated with collapsed chloroplast envelopes, disintegrated chloroplasts and very poor staining.
Language: English
Open Access status: bronze
OpenAlex ID: W1974733635
FWCI: 0.218
Cites: 35
Cited by: 10
Related to: 10