Light blocking film in a glasshouse impacts Capsicum annuum L. yield differentially across planting season

Chelsea R Maier; Sachin G Chavan; Norbert Klause; Weiguang Liang; Christopher I Cazzonelli; Oula Ghannoum; Zhong-Hua Chen; David T Tissue

doi:10.3389/fpls.2023.1277037

Light blocking film in a glasshouse impacts Capsicum annuum L. yield differentially across planting season

Front Plant Sci. 2023 Dec 19:14:1277037. doi: 10.3389/fpls.2023.1277037. eCollection 2023.

Authors

Chelsea R Maier¹, Sachin G Chavan², Norbert Klause¹, Weiguang Liang¹, Christopher I Cazzonelli^{1

2}, Oula Ghannoum^{1

2}, Zhong-Hua Chen^{1

2

3}, David T Tissue^{1

2

4}

Affiliations

¹ National Vegetable Protected Cropping Centre, Western Sydney University, Penrith, NSW, Australia.
² Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia.
³ School of Science, Western Sydney University, Penrith, NSW, Australia.
⁴ Global Centre for Land-Based Innovation, Western Sydney University, Penrith, NSW, Australia.

Abstract

High energy costs are a barrier to producing high-quality produce at protected cropping facilities. A potential solution to mitigate high energy costs is film technology, which blocks heat-producing radiation; however, the alteration of the light environment by these films may impact crop yield and quality. Previous studies have assessed the impact of ULR 80 [i.e., light-blocking film (LBF)] on crop yield and photosynthetically active radiation (PAR); however, an assessment of the spectral environment over different seasons is important to understand potential crop impacts through different developmental phases. In this study, two varieties (red and orange) of Capsicum annuum were grown across two crop cycles: one cycle with primary crop growth in the autumn (i.e., autumn experiment [AE]) and the other with primary crop growth in the summer (i.e., summer experiment [SE]). LBF reduced PAR (roof level: 26%-30%, plant canopy level: 8%-25%) and net radiation (36%-66%). LBF also reduced total diffuse PAR (AE: 8%, SE: 15%), but the diffuse fraction of PAR increased by 7% and 9% for AE and SE, respectively, potentially resulting in differential light penetration throughout the canopy across treatments. LBF reduced near-infrared radiation (700 nm-2,500 nm), including far-red (700 nm-780 nm) at mid- and lower-canopy levels. LBF significantly altered light quantity and quality, which determined the amount of time that the crop grew under light-limited (<12 mol m^-2 d^-1) versus sufficient light conditions. In AE, crops were established and grown under light-limited conditions for 57% of the growing season, whereas in SE, crops were established and grown under sufficient light conditions for 66% of the growing season. Overall, LBF significantly reduced the yield in SE for both varieties (red: 29%; orange: 16%), but not in AE. The light changes in different seasons in response to LBF suggest that planting time is crucial for maximizing fruit yield when grown under a film that reduces light quantity. LBF may be unsuitable for year-round production of capsicum, and additional development of LBF is required for the film to be beneficial for saving energy during production and sustaining good crop yields in protected cropping.

Keywords: Capsicum annuum L.; agricultural technology; energy use; light blocking film; light intensity; light quality; protected cropping; resource sustainability.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. We received financial support from the Horticulture Innovation Australia projects (Grant number VG16070 to DT, Z-HC, OG, CC; Grant number VG17003 to DT and Z-HC; Grant number LP18000 to Z-HC) and CRC Future Food Systems project P2-013 (DT, Z-HC, OG, and CC).