Nutrition and Fertilization Flashcards
Macronutrients
require large amounts, measured in percentage (carbon, oxygen, hydrogen, nitrogen, phosphorous, potassium)
Micronutrients ( zinc, boron, copper, manganese, chlorine, iron, nickel, and molybdenum
require in much smaller amounts are measured in parts per million
Nutrient supply from soil depends on
nutrient pool size=amount, solubility of nutrients=availability
How is nutrients taken up?
in water only by active roots on trees with leaves, active root growth is required,
Which nutrients are mobile
Nitrogen, Sulfur, Magnesium, and Chlorine, sometimes Potassium
Plant mobile nutrients
nutrients can remobilize from older part of the plant to new part, deficiency can be seen on older tissue
Plant immobile nutrients
nutrients get locked in place once it is incorporate, cannot relocate, seen on newer tissue
Low mobility nutrients
zinc, molybdenum, copper, and nickel
Immobile nutrients
manganese, iron, calcium
How do mobile nutrients move
xylem one way, phloem two ways, nutrients stored, support current and developing tissues
How do immobile nutrients move
xylem one way, transport water, supply required through growth and reproduction, fertilizers limited long term effectiveness
Mass flow soluble nutrients
movement of dissolved nutrients into plant as the plant absorbs water for transpiration, nitrate, sulfate, calcium, and mangnesium
Dissolution/Diffusion of insoluble elements
movement of nutrients to the root surface in response to a concentration gradient. phosphorus and potassium
What factors affect nutrient uptake and utilization
poor irrigation system, presence of hardpans, poor water infiltration, perched water tables, alkali spots, salinity, ph, nutrient fixation, low soil temperature, weather/climate, limitations of tree uptake and transport, low or high native soil fertility for one or more nutrients, root disease, weed competition
How do you sample leaves
minimum 12 trees, each sampled at least 25 yards apart, 10 leaves per tree located 5-7 feet from ground
Which nutrient are insoluble at pH above 5
Fe, Zn, and Manganese
What is the fate of a nutrient
removed in crop, remobilized, recycled,
What is effective nutrient management?
right nutrient, right organ, right time, and right concentration
Nitrogen deficiency
new leaves mobilize N at expense of old leaves, new leaves are pale, reduce shoot growth, reddish bark
Potassium deficiency
small leaves without chlorosis and scorched margins, worst on older leaves of current shoots, sparse foliage with pronounced dieback, yield declines as K declines
Phosphorus deficiencies
initially interveinal chlorosis then leaves became bright yellow desiccated and dropped, reduced stem diameter and limited canopy size
In the central valley which nutrients are most likely
zinc, copper, boron
What is the role of zinc
Required for auxin formation, involved in cell elongation, associated with chloroplast formulation, essential for pollen development, flower bud differentiation and fruit set
copper deficiency
apply copper EDTA as foliar treatment at 50% leaf expansion, can be mixed with Zinc, be applied several times in spring
What is the role of boron in plants
cell continue to divide but structural parts are not properly or completely formed, regulates carbohydrate metabolism, limits pollen germination and pollen tube growth, immobile
Boron Deficiency
tissue necrosis of growing points and young leaves, shoot tips die back, terminal buds remain dormant, lateral buds’ sprouts, flower clusters drop before fruit set
How do you efficiently apply nitrogen fertilizer?
Apply right rate, right time, right place, right source and monitoring
In the case of N deficiency older parts of the plant develop symptoms of deficiencies first
true
Which of the following is a greater sink for nitrogen in grapes
leaves
which nutrients have a greater role on pollen and pollination
Boron and Zinc
Nitrogen efficiency in well managed orchards is considered at about
70%
A C:N ratio of is the dividing line between mineralization immediate release and immobilization
20:1
Timing of Nitrogen application in non-bearing trees is important since the relative N uptake capacity on those trees is equal during the growing season
False
