Viticulture

Viticulture

Anthocyanin Biosynthesis in Shiraz Grape Berries

Here's one for the scientists. Surely there must be some amongst us? Analysis of the Expression of Anthocyanin Pathway Genes in Developing Vitis vinifera L. cv Shiraz Grape Berries and the Implications for Pathway Regulation By P. Boss, C. Davies and S. Robinson Abstract Anthocyanin synthesis in Vitis vinifera L. cv Shiraz grape berries began 10 weeks postflowering and continued throughout berry ripening. Expression of seven genes of the anthocyanin biosynthetic pathway (phenylalanine ammonia lyase [PAL], chalcone synthase [CHS], chalcone isomerase [CHI], flavanone-3-hydroxylase [F3H], dihydroflavonol 4-reductase [DFR], leucoanthocyanidin dioxygen-ase [LDOX], and UDP glucose-flavonoid 3-o-glucosyl transferase [UFGT]) was determined. In flowers and grape berry skins, expression of all of the genes, except UFGT, was detected up to 4 weeks postflowering, followed by a reduction in this expression 6 to 8 weeks postflowering. Expression of CHS, CHI, F3H, DFR, LDOX, and UFGT then increased 10 weeks postflowering, coinciding with the onset of anthocyanin synthesis. In grape berry flesh, no PAL or UFGT expression was detected at any stage of development, but CHS, CHI, F3H, DFR, and LDOX were expressed up to 4 weeks postflowering. These results indicate that the onset of anthocyanin synthesis in ripening grape berry skins coincides with a coordinated increase in expression of a number of genes in the anthocyanin biosynthetic pathway, suggesting the involvement of regulatory genes. UFGT is regulated independently of the other genes, suggesting that in grapes the major control point in this pathway is later than that observed in maize, petunia, and snapdragon.

Please click HERE for the full scientific paper.


Biodynamics - an Introduction

This is one of the most controversial topics in Viticulture, with a debate which has continued for several decades. There are a great many procedures which may or may not be carried out by all biodynamic practitioners. These range from carrying out certain procedures according to phases of the moon, to concocting various natural fertilisers, which mature in a cow-horn buried in the ground for a period of time. Whilst scientific proof of the effects and workings of the various methods so far seems elusive, there appears no doubt that wines made from grapes grown biodynamically can be of superior quality. Certainly some top wine-makers appear convinced - such great names as Olivier Leflaive from Chablis, Michel Chapoutier from the Rhone valley and Guy Cuisset from Bergerac.

This is one of the most controversial topics in Viticulture, with a debate which has continued for several decades.
There are a great many procedures which may or may not be carried out by all biodynamic practitioners.
These range from carrying out certain procedures according to phases of the moon, to concocting various
natural fertilisers, which mature in a cow-horn buried in the ground for a period of time.
Whilst scientific proof of the effects and workings of the various methods so far seems elusive,
there appears no doubt that wines made from grapes grown biodynamically can be of superior
quality. Certainly some top wine-makers appear convinced - such great names as Olivier Leflaive from
Chablis, Michel Chapoutier from the Rhone valley and Guy Cuisset from Bergerac.

Biodynamics is a spiritual-ethical-ecological approach to agriculture, food production and nutrition.
Biodynamics was first developed in the early 1920s based on the spiritual insights and practical
suggestions of the Austrian writer, educator and social activist Dr. Rudolf Steiner (1861-1925),
whose philosophy is called “anthroposophy.” Today, the biodynamic movement encompasses
thousands of successful gardens, farms, vineyards and agricultural operations of all kinds and sizes
on all continents, in a wide variety of ecological and economic settings.
Biodynamic vineyard managers strive to create a diversified, balanced vineyard ecosystem that generates health
and fertility as much as possible from within the vineyard itself. Preparations made from fermented manure,
minerals and herbs are used to help restore and harmonize the vital life forces of the vineyard and to
enhance the nutrition, quality and flavour of the grapes being grown. Biodynamic practitioners also
recognize and strive to work in cooperation with the subtle influences of the wider cosmos on soil,
plant and animal health.