The ontogeny and development of Vitis vinifera L. cv. Chenin blanc inflorescence in relation to phenological stages

The ontogeny and development of inflorescence primordia and flower formation were studied with the aid of scanning electron microscopy. Initiation and differenti ation of the first and second inflorescence primordia in each bud at the two basal nodes occured in the period middle October (12-15 d before bloom) to end November (25 d after bloom). A time lapse of 3 weeks between initiation of the first and second anlagen in a bud was observed. The second anlagen were initiated just after the differentiation of the first. Floral parts were formed in the order calyx, corolla, stamens and pistil and within 20 d after appearance of the inflorescence these parts were fully developed.