Study of the Term of Inflorescence Initiation and the Potential Bud Fertility of Tempranillo Cultivar Depending on Loading

L. ANGELOV and S. PANDELIEV
Agricultural University, Department of Viticulture, BG-4000 Plovdiv, Bulgaria

Abstract

ANGELOV, L. and S. PANDELIEV, 2005. Study of the term of inflorescence initiation and the potential bud fertility of Tempranillo cultivar depending on loading. Bulg. J. Agric. Sci., 11: 35-48

In the period 2002-2004 on the training, experimental and introduction site of the Agricultural University - Plovdiv a study was carried out on the term of inflorescence initiation and differentiation degree in Tempranillo cultivar depending on loading with winter buds.
It was established that the soil and climatic conditions in the region of Brestnik village were very favourable for grapevine growth, inflorescence initiation and differentiation. Inflorescence initiation in Tempranillo cultivar started in the second half of May until the middle of July. Loading did not affect greatly the term of inflorescence initiation. The effect of the meteorological conditions on that process was considerable. The lower day-and-night temperatures significantly impeded the process. The potential fertility coefficient decreased with the increase of loading but not proportionally to the number of buds left at pruning. Despite that, the increased loading led to the decrease of the number of inflorescences above 750mm and to the increase of the number of inflorescences of 550-750 mm.

Key words: inflorescense initiation, potencial bud fertility, cv. Tempranillo, bud loading