Academic Journal
View in EDS

Longer Photoperiod Substantially Increases Indoor-Grown Cannabis’ Yield and Quality: A Study of Two High-THC Cultivars Grown under 12 h vs. 13 h Days

Bibliographic Details
Title: Longer Photoperiod Substantially Increases Indoor-Grown Cannabis’ Yield and Quality: A Study of Two High-THC Cultivars Grown under 12 h vs. 13 h Days
Authors: Ashleigh Ahrens, David Llewellyn, Youbin Zheng
Source: Plants, Vol 13, Iss 3, p 433 (2024)
Publisher Information: MDPI AG, 2024.
Publication Year: 2024
Collection: LCC:Botany
Subject Terms: daylength, medicinal cannabis, lighting, controlled environment agriculture, flower initiation, Botany, QK1-989
More Details: Indoor-grown Cannabis sativa is commonly transitioned to a 12 h daily photoperiod to promote flowering. However, our previous research has shown that some indoor-grown cannabis cultivars can initiate strong flowering responses under daily photoperiods longer than 12 h. Since longer photoperiods inherently provide higher daily light integrals (DLIs), they may also increase growth and yield. To test this hypothesis, two THC-dominant cannabis cultivars, ‘Incredible Milk’ (IM) and ‘Gorilla Glue’ (GG), were grown to commercial maturity at a canopy level PPFD of 540 µmol·m−2·s−1 from white LEDS under 12 h or 13 h daily photoperiods, resulting in DLIs of 23.8 and 25.7 mol·m−2·d−1, respectively. Both treatments were harvested when the plants in the 12 h treatment reached maturity according to established commercial protocols. There was no delay in flowering initiation time in GG, but flowering initiation in IM was delayed by about 1.5 d under 13 h. Stigma browning and trichome ambering also occurred earlier and progressed faster in the 12 h treatment in both cultivars. The vegetative growth of IM plants in the 13 h treatment was greater and more robust. The inflorescence yields were strikingly higher in the 13 h vs. 12 h treatment, i.e., 1.35 times and 1.50 times higher in IM and GG, respectively, which is 4 to 6 times higher than the relative increase in DLIs. The inflorescence concentrations of major cannabinoids in the 13 h treatment were either higher or not different from the 12 h treatment in both cultivars. These results suggest that there may be substantial commercial benefits for using photoperiods longer than 12 h for increasing inflorescence yields without decreasing cannabinoid concentrations in some cannabis cultivars grown in indoor environments.
Document Type: article
File Description: electronic resource
Language: English
ISSN: 2223-7747
Relation: https://www.mdpi.com/2223-7747/13/3/433; https://doaj.org/toc/2223-7747
DOI: 10.3390/plants13030433
Access URL: https://doaj.org/article/899c0869c2964a638b647b4147652fc3
Accession Number: edsdoj.899c0869c2964a638b647b4147652fc3
Database: Directory of Open Access Journals
FullText Text:
  Availability: 0
CustomLinks:
  – Url: https://resolver.ebsco.com/c/xy5jbn/result?sid=EBSCO:edsdoj&genre=article&issn=22237747&ISBN=&volume=13&issue=3&date=20240201&spage=433&pages=433-433&title=Plants&atitle=Longer%20Photoperiod%20Substantially%20Increases%20Indoor-Grown%20Cannabis%E2%80%99%20Yield%20and%20Quality%3A%20A%20Study%20of%20Two%20High-THC%20Cultivars%20Grown%20under%2012%20h%20vs.%2013%20h%20Days&aulast=Ashleigh%20Ahrens&id=DOI:10.3390/plants13030433
    Name: Full Text Finder (for New FTF UI) (s8985755)
    Category: fullText
    Text: Find It @ SCU Libraries
    MouseOverText: Find It @ SCU Libraries
  – Url: https://doaj.org/article/899c0869c2964a638b647b4147652fc3
    Name: EDS - DOAJ (s8985755)
    Category: fullText
    Text: View record from DOAJ
    MouseOverText: View record from DOAJ
Header DbId: edsdoj
DbLabel: Directory of Open Access Journals
An: edsdoj.899c0869c2964a638b647b4147652fc3
RelevancyScore: 970
AccessLevel: 3
PubType: Academic Journal
PubTypeId: academicJournal
PreciseRelevancyScore: 970.390563964844
IllustrationInfo
Items – Name: Title
  Label: Title
  Group: Ti
  Data: Longer Photoperiod Substantially Increases Indoor-Grown Cannabis’ Yield and Quality: A Study of Two High-THC Cultivars Grown under 12 h vs. 13 h Days
– Name: Author
  Label: Authors
  Group: Au
  Data: <searchLink fieldCode="AR" term="%22Ashleigh+Ahrens%22">Ashleigh Ahrens</searchLink><br /><searchLink fieldCode="AR" term="%22David+Llewellyn%22">David Llewellyn</searchLink><br /><searchLink fieldCode="AR" term="%22Youbin+Zheng%22">Youbin Zheng</searchLink>
– Name: TitleSource
  Label: Source
  Group: Src
  Data: Plants, Vol 13, Iss 3, p 433 (2024)
– Name: Publisher
  Label: Publisher Information
  Group: PubInfo
  Data: MDPI AG, 2024.
– Name: DatePubCY
  Label: Publication Year
  Group: Date
  Data: 2024
– Name: Subset
  Label: Collection
  Group: HoldingsInfo
  Data: LCC:Botany
– Name: Subject
  Label: Subject Terms
  Group: Su
  Data: <searchLink fieldCode="DE" term="%22daylength%22">daylength</searchLink><br /><searchLink fieldCode="DE" term="%22medicinal+cannabis%22">medicinal cannabis</searchLink><br /><searchLink fieldCode="DE" term="%22lighting%22">lighting</searchLink><br /><searchLink fieldCode="DE" term="%22controlled+environment+agriculture%22">controlled environment agriculture</searchLink><br /><searchLink fieldCode="DE" term="%22flower+initiation%22">flower initiation</searchLink><br /><searchLink fieldCode="DE" term="%22Botany%22">Botany</searchLink><br /><searchLink fieldCode="DE" term="%22QK1-989%22">QK1-989</searchLink>
– Name: Abstract
  Label: Description
  Group: Ab
  Data: Indoor-grown Cannabis sativa is commonly transitioned to a 12 h daily photoperiod to promote flowering. However, our previous research has shown that some indoor-grown cannabis cultivars can initiate strong flowering responses under daily photoperiods longer than 12 h. Since longer photoperiods inherently provide higher daily light integrals (DLIs), they may also increase growth and yield. To test this hypothesis, two THC-dominant cannabis cultivars, ‘Incredible Milk’ (IM) and ‘Gorilla Glue’ (GG), were grown to commercial maturity at a canopy level PPFD of 540 µmol·m−2·s−1 from white LEDS under 12 h or 13 h daily photoperiods, resulting in DLIs of 23.8 and 25.7 mol·m−2·d−1, respectively. Both treatments were harvested when the plants in the 12 h treatment reached maturity according to established commercial protocols. There was no delay in flowering initiation time in GG, but flowering initiation in IM was delayed by about 1.5 d under 13 h. Stigma browning and trichome ambering also occurred earlier and progressed faster in the 12 h treatment in both cultivars. The vegetative growth of IM plants in the 13 h treatment was greater and more robust. The inflorescence yields were strikingly higher in the 13 h vs. 12 h treatment, i.e., 1.35 times and 1.50 times higher in IM and GG, respectively, which is 4 to 6 times higher than the relative increase in DLIs. The inflorescence concentrations of major cannabinoids in the 13 h treatment were either higher or not different from the 12 h treatment in both cultivars. These results suggest that there may be substantial commercial benefits for using photoperiods longer than 12 h for increasing inflorescence yields without decreasing cannabinoid concentrations in some cannabis cultivars grown in indoor environments.
– Name: TypeDocument
  Label: Document Type
  Group: TypDoc
  Data: article
– Name: Format
  Label: File Description
  Group: SrcInfo
  Data: electronic resource
– Name: Language
  Label: Language
  Group: Lang
  Data: English
– Name: ISSN
  Label: ISSN
  Group: ISSN
  Data: 2223-7747
– Name: NoteTitleSource
  Label: Relation
  Group: SrcInfo
  Data: https://www.mdpi.com/2223-7747/13/3/433; https://doaj.org/toc/2223-7747
– Name: DOI
  Label: DOI
  Group: ID
  Data: 10.3390/plants13030433
– Name: URL
  Label: Access URL
  Group: URL
  Data: <link linkTarget="URL" linkTerm="https://doaj.org/article/899c0869c2964a638b647b4147652fc3" linkWindow="_blank">https://doaj.org/article/899c0869c2964a638b647b4147652fc3</link>
– Name: AN
  Label: Accession Number
  Group: ID
  Data: edsdoj.899c0869c2964a638b647b4147652fc3
PLink https://login.libproxy.scu.edu/login?url=https://search.ebscohost.com/login.aspx?direct=true&site=eds-live&scope=site&db=edsdoj&AN=edsdoj.899c0869c2964a638b647b4147652fc3
RecordInfo BibRecord:
  BibEntity:
    Identifiers:
      – Type: doi
        Value: 10.3390/plants13030433
    Languages:
      – Text: English
    PhysicalDescription:
      Pagination:
        PageCount: 1
        StartPage: 433
    Subjects:
      – SubjectFull: daylength
        Type: general
      – SubjectFull: medicinal cannabis
        Type: general
      – SubjectFull: lighting
        Type: general
      – SubjectFull: controlled environment agriculture
        Type: general
      – SubjectFull: flower initiation
        Type: general
      – SubjectFull: Botany
        Type: general
      – SubjectFull: QK1-989
        Type: general
    Titles:
      – TitleFull: Longer Photoperiod Substantially Increases Indoor-Grown Cannabis’ Yield and Quality: A Study of Two High-THC Cultivars Grown under 12 h vs. 13 h Days
        Type: main
  BibRelationships:
    HasContributorRelationships:
      – PersonEntity:
          Name:
            NameFull: Ashleigh Ahrens
      – PersonEntity:
          Name:
            NameFull: David Llewellyn
      – PersonEntity:
          Name:
            NameFull: Youbin Zheng
    IsPartOfRelationships:
      – BibEntity:
          Dates:
            – D: 01
              M: 02
              Type: published
              Y: 2024
          Identifiers:
            – Type: issn-print
              Value: 22237747
          Numbering:
            – Type: volume
              Value: 13
            – Type: issue
              Value: 3
          Titles:
            – TitleFull: Plants
              Type: main
ResultId 1