Michigan State University 8/11/2020
Objectives:
1. To quantify how radiation intensity and
CO2 concentration during seedling production influence yield and morphology
2. To determine if differences at transplant persist through finishing in a common environment ) 1 ‒ 4 ·nm 1
‒ 3.5
Increase CO2 s · 2
‒ 3 2.5 2 Radiation saturation point 1.5 1 0.5 0 200 300 400 500 600 700 800
Net photosynthesis Wavelength (nm) Photon flux density(µmol·m
Radiation intensity Radiation compensation point
Not for Publication 1 Michigan State University 8/11/2020
Target radiation intensity (µmol·m–2·s–1) Target radiation intensity (µmol·m–2·s–1) Parsley 100 200 400 600 Dill 100 200 400 600 ’Giant of Italy’ ‘Bouquet’ 1200 1200 Increase light 12% increase intensity As CO2 concentration and/or CO when the 800 increased, 2 800 light intensity is concentration (ppm) concentration (ppm) concentration fresh mass 2 high 2 increased to increase fresh mass
Ambient CO Ambient CO 400 400 4 weeks after sowing 3 weeks after sowing Fresh mass (g) Fresh mass (g)
Target radiation intensity (µmol·m–2·s–1) Target radiation intensity (µmol·m–2·s–1) Parsley 100 200 400 600 Dill 100 200 400 600 ’Giant of Italy’ ‘Bouquet’ 1200 1200 Increase light As light intensity and/or intensity CO2 when the 800 increased, 800 light intensity is concentration (ppm) concentration (ppm) concentration fresh mass 2 17% decrease high 2 decreased to increase fresh mass
Ambient CO Ambient CO 400 400 Fresh mass (g) 4 weeks after sowing Fresh mass (g) 3 weeks after sowing
Target radiation intensity (µmol·m–2·s–1) Target radiation intensity (µmol·m–2·s–1) Parsley 100 200 400 600 Dill 100 200 400 600 ’Giant of Italy’ ‘Bouquet’ 1200 1200 As light intensity
increased, As light 800 plants 800 intensity concentration (ppm) concentration (ppm) concentration became more 2 46% decrease increased, 2 compact seedlings were more compact
Ambient CO Ambient CO 400 400 4 weeks after sowing 3 weeks after sowing Stem length (cm)
Not for Publication 2 Michigan State University 8/11/2020
Target radiation intensity (µmol·m–2·s–1) 100 200 400 600 Sage Dill Target radiation intensity (µmol·m–2·s–1) 100 200 400 600 ‘Extrakta’ ‘Bouquet’ 1200 1200
As light Increasing intensity seedling light increased, 800 intensity 800
fresh mass (ppm) concentration concentration (ppm) concentration 2
increases 2 increased finished yield
400 Ambient CO Ambient CO 400 5 weeks after sowing Fresh mass (g) Fresh mass (g) 4 weeks after transplant
Dill ’Bouquet’
Target radiation intensity (µmol·m‒2·s‒1) 100 200 400 600
4 weeks after transplant
Parsley ‘Giant of Italy’ Sage ‘Extrakta’
–2 –1 ) ) Target radiation intensity (µmol·m ·s ) Target radiation -1 -1 100 200 400 600 intensity (µmol·m‒2·s‒1) mol mol · · 100 200 400 600
1200 1200
No Fresh mass (g) 800 concentration (µmol concentration
concentration (µmol concentration 800 2 2 Difference 23.2 c 30.6 b 39.2 a 38.6 a
400 400 Ambient CO Ambient CO
4 weeks after transplant 5 weeks after transplant
Not for Publication 3 Michigan State University 8/11/2020
Seedling conclusions:
• Increasing CO2 when light intensity is high to increase dill fresh mass and stem width
• Increase CO2 to increase parsley fresh mass
Finished conclusions: • Parsley was not influenced by light
intensity or CO2
• Increasing radiation intensity to 400 µmol·m–2·s–1 increased dill and sage fresh mass
Seedling conclusions: • Increasing light intensity to 400 µmol·m–2·s–1:
. Increases dill and sage fresh mass . Decreases parsley fresh mass
. Increases stem width and decreases height
Not for Publication 4 Michigan State University 8/11/2020
Green butterhead lettuce ‘Rex’ and red Michigan State University oakleaf lettuce ‘Rouxai’ and other leafy Sean Tarr, Nathan Durussel, and Roberto Lopez greens will be grown at a TPFD of 150 or Co-optimize indoor 300 μmol·m–2·s–1 and a 20-h photoperiod environmental conditions at 22/10°C (ADT 20 °C), 25/13 °C (23 °C), (humidity, air movement, temperature, light, and and 28/15 °C (26 °C). CO2 concentration) to Sean Tarr, M.S. student increase yield and high- value attributes of leafy- . We will determine how temperature green vegetables while interacts with light quantity to minimizing opex regulate growth (fresh and dry weight) and quality attributes (leaf size, number, coloration, nutrients and phytonutrients) and influences Nathan post-harvest longevity. Durussel, Technician
Red Oakleaf ‘Rouxai’ Green butterhead lettuce ‘Rex’ and red Temperature (ºC) oakleaf lettuce ‘Rouxai’ and other leafy 22/10 25/13 28/15 greens will be grown at a TPFD of 100, 200, (ADT 20) (ADT 23) (ADT 26) –2 –1 or 300 μmol·m ·s from white LEDs at CO2 Radiation Intensity (μmol·m–2·s–1 ) concentrations of 400, 800, or 1,200 -1 150 300 150 300 150 300 µmol·mol and at 23 °C.
. We will quantify how TPFD and CO2 regulate growth (fresh and dry weight) and quality attributes (leaf size, number, coloration, and Green Butterhead ‘Rex’ phytonutrients).
Microgreens will be grown at 23 °C under Microgreens will be grown at 23 °C under WW LEDs providing a TPFD of 125 WW LEDs providing a TPFD of 125 μmol·m–2·s–1. μmol·m–2·s–1.
Followed by end-of-production lighting . No pre-harvest treatment (control) treatments from UV-A, UV-B LEDs (at 10 to 40 . Conventionally in a greenhouse μmol·m–2·s–1) or blue LEDs (40 or 80 μmol·m–2·s–1) Quality and phytonutrients: At harvest, we will quantify for 0, 3, or 6 days biomass, anthocyanins, carotenoids, luteins, total flavonoids, vitamin C, nutrients, and glucosinolates.
Brassica juncea L. ‘Red Lion’ (mustard) Brassica juncea L. ‘Red Lion’ (mustard) Daily Light Integral (mol·m–2·d–1) Daily Light Integral (mol·m–2·d–1) 6 12 18 6 12 18
Not for publication 1 Michigan State University 8/11/2020
On Farm trials Microgreens will be grown at 23 °C under WW LEDs providing a TPFD of 125 μmol·m–2·s–1. . Heliospectra . The Chefs Garden . No pre-harvest treatment (control) . Conventionally in a greenhouse
Postharvest Quality: Clamshells and plastic bags, stored in darkness at 4 °C, shelf life assessed after 0, 8, 12, 16, and 20 days.
Brassica juncea L. ‘Red Lion’ (mustard) Daily Light Integral (mol·m–2·d–1) 6 12 18
Not for publication 2