1. The behaviour of some varieties of snapdragon
(Antirrhinum majus L.) in forced cultures
for cut flower production
Author name: Gabriel Cristian MILOȘ
Coordinator Professor: Florin TOMA
International Student Symposium "Hortus Academicus“ March 31, Bucharest, Romania

2. Introduction
Snapdragon (Schrophulariaceae family) comes from mediterranean regions, are perennial plants with lanceolate linear leaves, opposite arranged in the lower part and alternate in the upper part of the plant (Săvulescu, 2010). The complex flowers exclude small insects, as the weight of relatively large bees such as bumble bees is required to depress the lower lip and gain access to nectar and pollen. The energy cost of flight is very high in bumble bees, constraining their behavior to maximize foraging efficiency (Heinrich, 1975) Snapdragon is intensive grown in forced culture for cut flower production in winter and spring, tall varieties being suitable for cut flower market (Selaru, 2002). Stem ramification may be stimulated through early pinching (Toma, 2013). As a cut flower grower, I have started with snapdragon cultivation in cold polytunnel (Crovu, Dâmbovița) and later in Hortinvest - UȘAMV Bucharest greenhouse, in order to compare varieties performance in terms of plants height or inflorescences length and post harvest treatment.
International Student Symposium "Hortus Academicus“ March 31, Bucharest, Romania

3. Materials and Methods
I bought the seeds from Sakata Ornamentals (Japan) choosing 4 cultivars of Antirrhinum majus ‘Calima Deep Rose’, ‘Calima Pure White’, ‘Admiral Pink Bicolour’ and ‘Admiral Purple’. As a general guideline, Sakata recommends ‘Admiral’ for winter / spring cultivation, and ‘Calima’ for summer and high temperatures.
I used 200 cell plug trays for sowing, Kekkila DSM2 peat substrate, not covered. Germination occured after 4-7 days, soil temperature Celsius degrees, pH = 5,8. The cotyledons developed after 8-14 days, light lux (16 hours on, 8 hours off), Ec = 0,75 dS/m, foliar fertilization ppm N – Power Leaf.
The next stage was growing of the first true leaves after days, soil temperature Celsius degrees, pH = 5,8, EC = 1 dS/m, daily liquid fertilization using 100 ppm N from Peters CALMAG Grower  CaO+2.5MgO+ME
International Student Symposium "Hortus Academicus“ March 31, Bucharest, Romania

4. Materials and Methods Fertilization program as follows:
I transplanted the seedlings in 45 cell plug trays (5 cm – cell diameter) after 30 days at two leaves stage, and planted in ground beds 55 DAS (days after sowing) in 4 rows at 22cm distance between rows and 15 cm distance in row (30 plants / sqm), fertilization 150 ppm N.
Fertilization program as follows:
Base fertilization – controlled released fertilizer Agroblen 5-6 months MgO+27SO4 – 50 g/sqm
Fertigation 1 gr / liter / week - Universol Blue MgO+ME, after 60 DAP - Universol Violet – MgO+ME
Foliar fertilization 1 / week (0,3%) - Agroleaf Power CALCIUM CaO+2.5MgO+Biostim.

5. Materials and Methods Post harvesting - Pulsating Treatment
Treatment with silver thiosulphate (S.T.S.) supplies the flower with silver ions which inhibit ethylene action and stems bending due to gravitropic response (Philosoph-Hadas, 1996).
Method applied: stand bunches in 0.02 M S.T.S. solution in plastic buckets for approximately 15 mins at room temperature foolowed by transfering bunches to water for at least on hour to allow silver to reach flower head (Realtime Flowers Brisbane, 2012)
I have prepared stock solutions of Silver nitrate (Ag NO3), Sodium thiosulphate (Na2S2O3) and then Silver thiosulphate (Ag2O3S2) (Madjar, Davidescu, 2014).

6. Materials and Methods Bed width 1 m Bed length 16m. Planting on 4 rows
Controlled release fertilizer 
Agroblen - 50 grams / sqm
Weed control fabric

7. Materials and Methods 2 rows on the right side – not pinched
2 plant support nets – h1=30cm and h2=80cm.
Vertical posts – at every 5m.
2 rows on the left side – pinched
at h=15cm stage.
Planting distances 22cm / 15cm.

8. Materials and Methods Observations:
Flowering 130 DAS – not pinched plants and 145 DAS for pinched plants.
First cultivars to flower – Calima Pure White and Admiral Purple
Maximum inflorescence length – unpinched plants – DAF (days after flowering.
Observations:
Measurments and countings at every other week:
- leaves number, internode distances, plant height and flowers number.

9. Results and Discussions

11. Admiral Pink Bicolour Inflorescence length 25 cm Toatal height 140 cm
International Student Symposium "Hortus Academicus“ March 31, Bucharest, Romania

12. Calima Deep Rose Inflorescence length 30 cm Total height 163 cm

13. Admiral Purple Inflorescence length 36 cm Total height 150 cm

14. Calima
Pure White Inflorescence length 46 cm Total height 155 cm

15. Comparisons with The Society of American Florists (SAF) grading standard for snapdragon (Armitage, Laushman, 2003)

16. A) Water + STS; B) Water only

17. Conclusions and recommendations
From the conducted experiments, in my environmental conditions, I can conclude that the best performer was Calima, especially in warm conditions, both in terms of total height and inflorescence length.
An agril cover in floral stage inhibits pollination by bees and allows the development of a very long inflorescence.
The pinched varieties have reached the highest quality in terms of American Florists grading standards.
Best results regarding vase life or blocking stems bending were achieved using water + STS pulsing.
International Student Symposium "Hortus Academicus“ March 31, Bucharest, Romania

18. References
Allan M. Armitage, Judy Laushman Specialty Cut Flowers: The Production of Annuals, Perennials, Bulbs, and Woody Plants for Fresh and Dried Cut Flowers Timber Press, Portland, Ore.2008
Heinrich Berndt Energetics of pollination. Annual Review of Ecology and Systematics, Vol 6,
Madjar Roxana, Davidescu Velicica Agrochimie. Facultatea de Horticultură, București.
Realtime Flowers Brisbane
Sonia Philosoph-Hadas, Shimon Meir, Ida Rosenberger, and Abraham H. Halevy Regulation of the Gravitropic Response and Ethylene Biosynthesis in Gravistimulated Snapdragon Spikes by Calcium Chelators and Ethylene lnhibitors’. Plant Physiol. 110:
Săvulescu Elena Botanică sistematică. Facultatea de Horticultură, București.
Șelaru Elena Cultura Florilor de Grădină. Editura Ceres, București.
Toma Florin Floricultură. Facultatea de Horticultură, București.
International Student Symposium "Hortus Academicus“ March 31, Bucharest, Romania