JCB • VOLUME 173 • NUMBER 3 • 2006 316 C aren Norden, Manuel Mendoza, Yves Barral (ETH, Zurich, Switzerland), and colleagues have found a new checkpoint in yeast cell division. Cytokinesis, they show, is delayed until chromosomes are out of the way, thanks to a pathway that monitors the spindle midzone. If cytokinesis were to occur too soon, chromatids still lingering in the spindle midzone mig...

A breeding program has been developed since 1994 (done by Dr A. Trigui), by controlled pollinations of the Tunisian olive oil variety Chemlali Sfax in order to improve the qualities of this variety (higher oil percentage and a better chemical composition). These controlled pollinations have produced a population of new genotypes presented a wide genetic diversity which was very interesting for ...

The peptide INFLORESCENCE DEFICIENT IN ABSCISSION (IDA), which signals through the leucine-rich repeat receptor-like kinases HAESA (HAE) and HAESA-LIKE2 (HSL2), controls different cell separation events in Arabidopsis thaliana. We hypothesize the involvement of this signaling module in abscission processes in other plant species even though they may shed other organs than A. thaliana. As the fi...

Throughout their life cycle, plants produce new organs, such as leaves, flowers, and lateral roots. Organs that have served their purpose may be shed after breakdown of primary cell walls between adjacent cell files at the site of detachment. In Arabidopsis, floral organs abscise after pollination, and this cell separation event is controlled by the peptide INFLORESCENCE DEFICIENT IN ABSCISSION...

1-Aminocyclopropane-1-carboxylic acid (ACC) supplied via the cut base of detached olive shoots caused a burst of ethylene from leaves, but other cyclopropanes tested did not exhibit this effect. Ethephon (ET) and another ethylene-releasing compound caused a prolonged increase in ethylene evolution. ACC had only a very limited effect on leaf abscission regardless of concentration, whereas shoots...

Phenology and reproductive biology of cultivated species are important for the comprehension of the requirements for fruit and seed production and the management of pollinators. This study aimed to characterise the phenology, reproductive biology and growing degree days of the grapevine 'Isabel' (Vitis labrusca) in northeastern Brazil during January 2011 (P1), Augst 2011 (P2), April 2012 (P3) a...

Cauliflower (Brassica oleracea var. botrytis) and broccoli (B. oleracea var. italica) differ in the developmental stage of the reproductive meristem at harvest. A cauliflower head is formed by arrest at the inflorescence meristem stage and broccoli at the flower bud stage, and the horticultural value of the crop depends on synchronous development across the head. In other plant species, gibbere...

Geraniums are sensitive to ethylene during shipping and respond by abscising their petals. Treatment of stock plants with ethylene (ethephon) in order to increase cutting yield resulted in earlier flowering in Pelargonium × hortorum ‘Kim’ and ‘Veronica’, but did not result in increased susceptibility to petal abscission following exposure to 1.0 μL·L–1 ethylene. Treatment of ‘Kim’, ‘Veronica’, ...