Figure 1.

Scheme showing the experimental design to analyze PLs and AR formation in cucumber explants. Primary root (PR) systems of 7-d-old cucumber seedlings were removed, and explants were treated as follows. To study PL signaling, explants were subjected to in vivo labeling with ³²Pi followed by short treatments. PLs were extracted from hypocotyl (H) segments 5 mm long from the base of the hypocotyl (white square), where ARs develop. Radiolabeled PLs were then separated by TLC. To analyze AR formation, cucumber explants were treated for different times and subsequently transferred to water for 5 d. The photograph shows seven ARs formed at the hypocotyl base. C, Cotyledon. Bars, 5 mm.