Tomatoes
Tomato Spray Programme
Slicing Tomatoes: Heat Stress
Department: Agronomy
Stellenbosch University - 2023 (MSc)
Randomised block design
Objective:
To evaluate the effect of C4L on tomato plants for post-harvest quality of slicing tomatoes grown under heat stress.
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Two types of tomato seedlings were used, Cultivar 1 & Cultivar 2, which received a drenched application of C4L two weeks after being planted.
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Control seedlings did not receive any treatment.
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Fourteen seedlings from each group were transplanted.
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All seedlings were grown in a temperature-controlled greenhouse (16°C at night, 30°C during the day) with standard trellising.
Fruit Firmness
Slicing Tomatoes: Heat Stress
Department: Agronomy
Stellenbosch University - 2023 (MSc)
Randomised block design
Post-harvest evaluations showed significant improvements in fruit firmness for both cultivars with C4L spray and drench treatments.
Additionally, the post-harvest plus 7-day evaluation resulted in statistically significant firmness gains for one cultivar with both treatments, while the other cultivar displayed a numerical increase.
Brix (%)
Slicing Tomatoes: Heat Stress
Department: Agronomy
Stellenbosch University - 2023 (MSc)
Randomised block design
Both soil and drench applications of C4L significantly increased the Brix level of two slicing tomato varieties at harvest, with an average improvement of 11%.
Cross section of a Tomato Stem - Electron Microscope
Solanum lycopersicum
Department: Agronomy
Stellenbosch University - 2023 (MSc)
Trichome Growth & Development
Solanum lycopersicum
Department: Agronomy
Stellenbosch University - 2023 (MSc)
The application of C4L significantly enhanced trichome development on tomato florets, improving both non-glandular trichomes (long, hair-like structures) and glandular trichomes (short, bulb-shaped structures).
These trichomes play critical protective roles by synthesizing, storing and secreting essential substances that contribute to plant defense and overall health.
Seedling Growth & Development
Colombia - 2012
The C4L programme significantly enhanced seedling length and overall development, both 5 days after the first application and 30 days after the second application.
Fruit Set
Vredendal
6 Replicate trial
The C4L programme increased fruit set by 25%, outperforming the grower's programme.
C4L application dosage & timing:
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250 mL/ha
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3 x 7-day intervals
Evaluation: 7 days after the last application
Yield (t/ha)
Greenhouse Tomatoes
Groblersdal - 2012
Semi-commercial trial
UTC
C4L
The C4L programme delivered a 16% yield increase compared to the untreated control (UTC), resulting in a return on investment (ROI) of R4889/ha.
C4L application dosage & timing:
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50 mL/100 L water
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Apply every two weeks
Yield (t/ha)
Vioolsdrift
Commercial trial
Over five weekly harvests, the C4L treatment consistently demonstrated a yield increase at each harvest date, culminating in a 15% overall yield increase for the C4L programme.
C4L application dosage & timing:
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13 Sep: 100 mL/ha
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27 Sep: 350 mL/ha
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28 Oct: 500 mL/ha
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14 Nov: 500 mL/ha
Fruit Quality
Vredendal - 2013
Randomised trial
This trial compared varying numbers of C4L applications to the grower's standard practice and an untreated control to assess their impact on the occurrence of russeting and cracking.
All C4L treatments outperformed both the untreated control and the grower standard, with increased applications of C4L demonstrating a lower incidence of russeting and cracking.
Fruit Colour & Quality
2008
First harvest: 19 December (100 fruit per sample)
C4L application dosage & timing:
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50 mL/100 L water
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28 Nov
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5 Dec
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12 Dec
The C4L treatment resulted in 10% more coloured fruit at the first harvest and consistently improved colour development across all evaluation dates.
It also enhanced stem-end fruit finishing.
Additionally, in an 8-person blind tasting study, 7 out of 8 participants preferred the C4L-treated fruit.