Too CO2 for You?
True or False: Carbon dioxide is lighter than air.
False. Carbon dioxide is heavier than air.
Name 3 of the photoreceptors that plants utilize.
Red phytochrome
Far red phytochrome
Cryptochrome (blue)
Pototropin (UV-A)
Chlorophyll A
Chlorophyll B
What is a microgreen?
A microgreen is simply an immature plant, a crop that we do not allow to fully grow into a mature developed crop.
True or False: The color of the cotyledons doesn’t matter at Transplant; only true leaves accurately show prop health.
False, cotyledon health is the key factor in noticing initial stress for propagation.
This mineral micronutrient is involved in the metabolism of ammonium.
Molybdenum
What is the name of the structure that allows plants to take gaseous carbon dioxide internally?
Stomata
What is the name for the range of light spectrum between 400nm-700nm?
100 Bonus: What is the name for the range of light spectrum between 400nm-750nm?
Photosynthetically Active Radiation (PAR)
Extended Photosynthetically Active Radiation (e-PAR) includes far red.
What are the 3 main plant components prior to harvest that make up a single microgreen?
The cotyledon (the first true leaves) and the hypocotyl (the stem of the plant) the roots!
What is the optimal number of true leaves that we want our lettuce to have at propagation before transplant?
At least 4-5 leaves
This mineral nutrient is responsible for the most basic unit of energy within the cell. It is also key for the phospholipid bilayer.
100 Bonus: Is it mobile or immobile?
Phosphorus
Bonus: Mobile
Name the process where carbon dioxide is "fixed" into components and used to make sugars that fuel the actions of the cell and growth of the plant.
200 Bonus: Name the sugar that is made in this process.
Photosynthesis (Calvin-Benson cycle)
200 Bonus: Glucose
What is the difference between PFD and PPFD?
Photon Flux Density is the measurement of the volume of all light as photons per second.
Photosynthetic Photon Flux Density is the measurement of the volume of only the light the plants use for photosynthesis as photons per second.
Let’s say our micros are extremely wet coming out of the growzone for harvest what are 3 of the most impactful potential stressors that are causing this negative reaction?
Density, humidity, & air flow.
Name two variables of control we can change to decrease stretching in the lettuce leaves.
Changing the density of plants per sqft, increasing the light intensity, and adding more blue light to the spectrum.
This element is used by the plant to create heme proteins that are precursors of chlorophyll.
100 Bonus: What visible symptom would you expect if a plant was deficient in this element?
Iron
100 Bonus: Chlorosis
Glucose is created and consumed in many ways by the cell. What polysaccharides (complex sugar) structure is created by the cell by connecting long chain of glucose into the structure of cell walls?
400 Bonus Points: Does the human body make enzymes to break down that polysaccharide?
Cellulose is the main component of cell walls in plants. It consists of chains of 500–3000 b-glucose units connected by 1,4’-glycoside linkages.
400 Bonus: Despite the similarity in structure between cellulose and starch, humans have the necessary enzymes to digest only starch. Humans rely on symbiotic relationships with gut microbes to liberate glucose from cellulose.
The LED light fixtures emit heat as a byproduct in the form of radiation. What is it called when that heat is transferred to plants, surfaces, or grow techs through the air?
Convection
Which macronutrient is the main resource for carbohydrate synthesis, raw material for cellulose synthesis, and is the only non-mineral "nutrient" that we have to supplement in the grow zone?
Carbon via carbon dioxide.
Name three abiotic stress factors experienced at the propagation stage have been correlated to a higher risk of tip burn at harvest.
Cold stress, damage to the apical meristem, and drought stress.
What two mineral nutrients are responsible for the integrity of the cell wall.
200 Bonus: Are they mobile or immobile?
100 Bonus: Name the non-mineral structural component of the cell wall.
Boron and Calcium
200 Bonus: Both immobile
100 Bonus: Cellulose
True or False: All of the sugars that the plant has accumulated throughout the photoperiod are kept intact within the cells during the dark period.
100 Bonus: What would you expect to happen if the plant did not generate sufficient amounts of sugars during the photoperiod?
False. Cells still have functions during the dark period. Those cells need to use the sugars accumulated for energy to sustain them through the dark period.
100 Bonus: Growth as a whole would slow down and the taste profile would change as well.
What is photomorphic radiation?
Photomorphic radiation is the light that causes plants to respond (phototropism) even if it isn't the correct spectrum or insufficient intensity for photosynthesis.
This mineral macronutrient is antagonistic to calcium and is vital for the formation of chlorophyll.
Magnesium
There are stunted and chlorotic plants on a prop table with normal density, oh no! what are the 3 general abiotic stressors causing this issue?
Irrigation (volume or frequency), Lighting (or lack thereof), and nutrients (toxicity or deficiency)
This element primarily makes up proteins, nucleic acids, amino acids, and numerous secondary compounds. It is abundant in the atmosphere and needs to be fixed by microorganisms, decomposition, lightning, or human manufacturing. It is added into our irrigation system in two distinct forms. It also makes up 2% of total plant biomass, which is the most of any mineral nutrient.
200 Bonus: Name the two forms of this element in our nutrients.
Nitrogen
200 Bonus: Nitrate and Ammonium