Ch 3 : The Growing Environment Flashcards
What are the benefits of sunlight
- anthrocyanin development
- tannin development (preveraison) and polymerisation (post-veraison)
- ripening/sugar accumulation (increase photosynthesis)
- development of aroma and flavour precursors
What natural aspects will influence sunlight (photo radiation and heat)
lattitude
altitude
slope
aspect
water bodies
winds
soil characteristics
mist/fog/clouds
diurnal range
How can sunlight negatively affect the grape?
- sunburn
- water stress through solar radiation
Explain transpiration
the stomata on the underside of the leaf opens, allowing water to evaporate and creating a pressure system that pulls water from the roots and trunk to the canopy and grapes.
what are the functions of the stomata?
- transpiration
- ingress of CO2
- release of oxygen
- water retention in drought conditions
When does water most benefit the vine
during the shoot and leaf development
when will the vine benefit from mild water stress?
ripening, to ensure the vine directs resources to the grapes and not the canopy
What factors influence water availability to the vine?
- soil characteristics
- temperature
- rainfall
- evapotranspiration rate
What are the main nutrients a vine needs?
nitrogen
potassium
phosphorus
calcium
magnesium
How do nitrogen levels affect the vine
It influence grape vigour and quality as it is require for photosynthesis in the chlorophyll
Too much causes excess growth
Lack creates chlorosis and lower production
How does potassium affect the vine?
It regulates water flow and when potassium levels are high, are linked to a higher pH
Low levels lead to low sugar accumulation and poor vine growth
What is mineralization?
the conversion of organic compounds into bioavailable nutrients by decomposer organisms in the soil
How does soil texture influence nutrient accessibility?
high ratios of clay allow soils to hold nutrients as there is more water within which these nutrients can be dissolved and absorbed
What are the 5 methods of climate classification?
GDD
Huglin Index
MJT
GST
Koppen’s Classification
Compare the GST with MJT
MJT measures mean temp in the hottest season alongside humidity, continentality, and sunlight hours. est. 1980.
GST uses the temperature of the whole growing season to classify regions on a scale.
