This was a poster that was presented at the Combined Congress at Stellenbosch University in 2009. It lists the effects of how seaweed extracts and starter solutions contribute towards reducing transplant shock in tomato seedlings

1. THE EFFECTS OF AFRIKELP® LG - 1 AND A STARTER
SOLUTION ON REDUCING TRANSPLANT SHOCK IN
TOMATO SEEDLINGS
Deborah Robertson-Andersson , B, Nzanza and Diana Marais 1 2 3
1. Biodiversity and Conservation Biology department, University of the Western Cape, Belville,
2. Natuurboedery Research Center, ZZ2 farms, P. O. Box 19, Mooketsi, 0825
3. Department of Plant production and Soil Science, University of Pretoria
Email first author: drobertson-andersson@uwc.ac.za
INTRODUCTION OBJECTIVE
Commercial seaweed extracts have been used since the The aim of these experiments was to determine the effects
transplanted vegetables such as tomato, eggplant, pepper,
1950’s (Stephenson, 1968). Internet (Annon, 2009) and of different applications of seaweed extract (AfriKelp® LG-1)
muskmelon, watermelon, cabbage, cauliflower and broccoli
literature searches reveal a wide variety of proposed benefits and starter solution application on the roots of Nemo-Netta
(Wells, 2009). There are numerous advantages to starter
one of which is reducing transplant shock of seedlings through tomato seedlings. following transplanting.
solutions in that they are easy to prepare, they are easily
promotion of root growth (Stirk et al. 2003, 2004; Stirk & van dissolvable with no residue, there is little risk of plant injury
Standen, 2006). (burning) they contain no potentially harmful salts which
Starter solutions are mixtures of soluble fertilizer and water accumulate and cause problems and the nutrients in starter
used to get young plants off to a good start (Sayre, 1943; solutions are immediately absorbed and utilized by plants, thus
Muehmer & Brimner 1987; Wells, 2009). The fertilizer material promoting rapid plant response and reducing plant transplant
easily dissolves in water and the nutrients are readily available shock (Wells 2009).
for plant uptake. Starter solutions are used primarily for
MATERIALS AND METHODS
• Plant nutrition, pest and disease management followed ZZ2 protocols.
• The experiment was conducted at the experimental farm of the Natuurboedery Research
Center, Mooketsi Station Limpopo Province during the winter – spring period of 2008.
• Plants were destructively harvested at weekly intervals.
• Tomato seedlings Nemo-Netta were supplied by Hishtill SA nurseries after 4 weeks growth
• At each measurement period, plants were removed from the bags, the rooting material washed
and an average height of 10 cm (+ 1 cm).
away to expose the roots. The plant height (shoot length), root length and stem diameter
(ø) were measured, plants were also dried 50 ºC for 70 hours to obtain a dry root to shoot
• Treatments consisted of a control a dip for three minutes of 1:1000; 1:500 and 1:250 Afrikelp
ratio.
LG-1 solution as well as the above repeated with a starter solution of H3PO4+ NH4NO3.
• Results were analysed statistically using STATISTICA V6, ANOVA followed by a Turkey LSD
• The trial was laid out in a linear fashion with each treatment having twelve replicates.
post hoc test.
RESULTS AND DISCUSSION
• The results showed that a starter solution and AfriKelp® LG-1 solution helped to reduce
transplant shock and increase root growth (figure 4) over the control.
• Significant increases were observed in shoot height; root length; stem diameter; number of
blossoms and fruit yield (figures 1 – 5). However the starter solution did not have as great
an effect as the combination of AfriKelp® and the starter solution or the AfriKelp® alone.
• The best AfriKelp® LG-1 dilution to use was a 1:500 dilution, this resulted in a tomato yield
that was three times the control (see figure 1), while a starter solution with an AfriKelp®
root dip of 1:1000 dilution produced the next best yields at over double that of the control
(see figure 1).
• The root length data showed greater variability with indications that higher applications are
more beneficial and increase root growth.10
FIGURE 1
maximum and minimum as well as 95 % confidence intervals. ANOVA showed significant differences:
df = 23; f = 3.96; p = 0.01.
FIGURE 5
FIGURE 4
FIGURE 3
FIGURE 2
Box and whisker plot of plant height in cm after
Box and whisker plot of root length in cm after 10 weeks
Box and whisker plot of number of stem diameter in
Box and whisker plot of number of flowers
10 weeks in each treatment. Plot shows mean,
in each treatment. Plot shows mean, maximum and
mm after 10 weeks in each treatment. Plot shows
after 10 weeks in each treatment. Plot shows
maximum and minimum as well as 95 % confidence
minimum as well as 95 % confidence intervals. ANOVA
mean, maximum and minimum as well as 95 %
mean, maximum and minimum as well as
intervals. ANOVA showed significant differences:
showed significant differences:
confidence intervals. ANOVA showed significant
95 % confidence intervals. ANOVA showed
df = 23; f = 3.47; p = 0.01.
df = 23; f = 2.15; p = 0.01.
differences:
significant differences:
df = 23; f = 8.18; p = 0.0003.
df = 23; f = 3.38; p = 0.02.
CONCLUSION
Starter solutions do have benefit when applied to tomato seedlings as has been shown by previous research, however our data suggests that promotion of
the root system through addition of a seaweed extract or other root promotion product, followed by starter solutions after 3 weeks will have the greatest
benefit in reducing transplant shock and ultimately improving tomato yields.
ACKNOWLEDGEMENTS
The authors wish to thank ZZ2 and Afrikelp (Pty) Ltd. for providing products and funding for this research. Special thanks to Danie Odendaal, Cleophas and the Natuurboedery staff.
REFERENCES
Anon 2009. Seaweed extracts: plant growth stimulants. Chase Organics GB Ltd. http://www.chaseorganics.co.uk/trials-information.html
Crouch, I. J. & Van Staden, J. 1994. Commercial seaweed products as biostimulants in horticulture. J. Home and Consumer Hort. 1: 19-76
Muehmer, J. K. & Brimner J. H. 1987. The effects of nutrient root dips on tomato transplants in Ontario. Acta Hort. (ISHS) 198:187-190.
Symposium on the Timing of Field Production of Vegetables http://www.actahort.org/books/198/198_23.htmI.
Stephenson, W. A. 1968. Seaweeds in agriculture and horticulture. Faber and Faber. London.
Sayre, C. B. 1943. Starter Solutions for Tomato Plants for 1943. Agricultural Experiment Station. New York State Agricultural Experimen
t Station Bulletin (1885-1970).
Stirk, W, A. & van Staden, J. 2006. Seaweed products as biostimulants in. agriculture. In: Critchley, A. T.; Ohno, M. & Largo, D. B. (eds)
World seaweed resources: an authoritative reference system. Eti Informaiton services Ltd.
Stirk, W. A.; Novák, O.; Strnad, M. & van Staden, J. 2003. Cytokinins in macroalgae. Plant Growth Regulation 41: 13-24
Stirk WA, GD Arthur, AF Lourens, O Novák, M Strnad & J van Staden 2004. Changes in cytokinin and auxin concentrations in seaweed
concentrates when stored at an elevated temperature. Journal of Applied Phycology 16: 31 – 39.
Wells. O. 2009. Starter Solutions for Vegetable Crops UNH Extension Vegetable specialist. http://extension.unh.edu/resources/files/
Resource000618_Rep640.pdf