Page 187 - Plant Canada 2024 Proceeding

PLANT CANADA 2024

[O165a] TEMPERATURE IMPACT ON PLANT GROWTH AND DEVELOPMENT OF SELECTED
VEGETABLES. Peter A. Ofori, Raphael Ofoe, Efoo B. Nutsukpo, and Lord Abbey. Department of Plant,
Food, and Environmental Sciences, Faculty of Agriculture, Dalhousie University, 50 Pictou Road, Bible
Hill, NS B2N 5E3, Canada
Corresponding author: loab07@gmail.com

Temperature stress impacts the growth, development, and productivity of crops, and this continue to be
important due to sustained global climate change. A study was performed to determine the effects of
different temperatures (10°, 22°, and 35°C) on the morpho- physiological and biochemical responses of
mint, lettuce, and tomato in a controlled environment. The results revealed that plant height and SPAD
value of mint were not significantly (p > 0.05) affected by 35°C and 22°C, but reduced by ca. 51% and
38% respectively, compared to 22°C. The 10°C and 35°C significantly (p < 0.001) reduced plant height by
55% and 28%; and stem girth by ca. 60% and 49% of lettuce, respectively compared to 22°C. The height
and stem girth of tomato were not significantly (p > 0.05) altered under both 22°C and 35°C, but were
reduced considerably by ca. up to 62% and 66% respectively under 10°C compared to 22°C. The SPAD
value was significantly (p < 0.001) increased by ca. 42.3% under 10°C compared to 22°C and 35°C. Total
protein, sugar, carotenoids, flavonoids and phenolics contents were significantly (p < 0.001) affected by
the interaction between crop species and growth temperature. The findings can contribute to the
development of strategies for improving the tolerance of these crops to temperature extremes and
ensuring food security in the face of climate change. Further studies should be conducted to evaluate the
effect of these temperature regimes on the metabolite profile of these selected vegetables.
Keywords: climate change, abiotic stress, cold stress, heat stress, stress tolerance

*[O165b] EXPLORING THE IMPACT OF FAR-RED AND BLUE LED LIGHT RATIOS ON BOTRYTIS
1
1
CINEREA’S MORPHOGENESIS. Abheet Aulakh , William Jordan , and Valerie Gravel . Department of
1 1
Plant Science, McGill University – Macdonald Campus, 21111 Lakeshore Road, Sainte-Anne-de-
Bellevue, QC H9X3V9
Correspondence to: valerie.gravel@mcgill.ca

Botrytis cinerea is the most important necrotrophic fungal pathogen infecting about 200 species of crops.
Along with field crops, its devastating effect in control environment cropping system is of major concern.
Being a fragile fruit, strawberries are greatly affected by grey mold caused by Botrytis cinerea. Current
management strategies, primarily fungicides, face challenges due to the pathogen's genetic variability
and widespread fungicide resistance. While considering the pathogen’s response to light for inducing
adaptive response, this study explores an innovative approach using light manipulation to inhibit the
morphogenesis of B. cinerea and enhance plant resistance. The adaptability, energy efficiency, and
customizable spectrum of light-emitting diodes (LEDs) offer promising tools for this purpose. Recent
research has demonstrated that specific wavelengths of light, particularly red, far-red, and blue, can
significantly affect plant-pathogen interactions by altering the pathogen development and increasing host
resistance. Based on these findings, our study aimed to evaluate the effects of different light ratios of far-
red to blue light (5:1, 1:5, and 1:1) on strawberry resistance to B. cinerea, with a particular focus on
changes in the pathogen morphogenesis. Three experimental assays were conducted to assess the
effect of light treatments in comparison to control treatments (ambient and dark) on mycelial growth,
sporulation, and spore germination. Results showed an interesting observation with unaffected mycelial
growth under light treatments but a significant effect on sporulation among the treatments, as 5:1 and 1:5
completely inhibited the spore production and there was less sporulation in 1:1 as compared to dark and
ambient light controls. Considering the spore germination after 7 hours post inoculation, blue and far-red
dominant light ratios (1:5 and 5:1) have lower germination percentage than other treatments. These
observations indicate that manipulating light spectra through LEDs can potentially disrupt the life cycle of
B. cinerea, thereby reducing its virulence.

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