The behaviour of some varieties of snapdragon Antirrhinum

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, 2017 - Bucharest, Romania

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, 2017 - Bucharest, Romania

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 DSM 2 peat substrate, not covered. Germination occured after 4 -7 days, soil temperature 16 -18 Celsius degrees, p. H = 5, 8. The cotyledons developed after 8 -14 days, light 16. 000 lux (16 hours on, 8 hours off), Ec = 0, 75 d. S/m, foliar fertilization 5075 ppm N – Power Leaf. The next stage was growing of the first true leaves after 15 -28 days, soil temperature 12 -15 Celsius degrees, p. H = 5, 8, EC = 1 d. S/m, daily liquid fertilization using 100 ppm N from Peters CALMAG Grower 14+06+14+6. 5 Ca. O+2. 5 Mg. O+ME International Student Symposium "Hortus Academicus“ March 31, 2017 - Bucharest, Romania

Materials and Methods 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 22 cm 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 15+08+16+5 Mg. O+27 SO 4 – 50 g/sqm - Fertigation 1 gr / liter / week - Universol Blue 18+11+18+2. 5 Mg. O+ME, after 60 DAP - Universol Violet – 10+10+30+3. 3 Mg. O+ME - Foliar fertilization 1 / week (0, 3%) - Agroleaf Power CALCIUM 11+05+19+9 Ca. O+2. 5 Mg. O+Biostim.

Materials and Methods Post harvesting - Pulsating 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 NO 3), Sodium thiosulphate (Na 2 S 2 O 3) and then Silver thiosulphate (Ag 2 O 3 S 2) (Madjar, Davidescu, 2014).

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

Materials and Methods 2 rows on the left side – pinched at h=15 cm stage. Planting distances 22 cm / 15 cm. 2 rows on the right side – not pinched 2 plant support nets – h 1=30 cm and h 2=80 cm. Vertical posts – at every 5 m.

Materials and Methods Observations: Measurments and countings at every other week: - leaves number, internode distances, plant height and flowers number. • 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 – 25 -28 DAF (days after flowering.

Results and Discussions

Admiral Pink Bicolour Inflorescence length 25 cm Toatal height 140 cm International Student Symposium "Hortus Academicus“ March 31, 2017 - Bucharest, Romania

Calima Deep Rose Inflorescence length 30 cm Total height 163 cm

Admiral Purple Inflorescence length 36 cm Total height 150 cm

Calima Pure White Inflorescence length 46 cm Total height 155 cm

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

A) Water + STS; B) Water only

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, 2017 - Bucharest, Romania

References • • Allan M. Armitage, Judy Laushman. 2003. 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. 1975. Energetics of pollination. Annual Review of Ecology and Systematics, Vol 6, 139 -170. Madjar Roxana, Davidescu Velicica. 2013. Agrochimie. Facultatea de Horticultură, București. Realtime Flowers Brisbane. 2015. http: //www. rtfb. com. au/flowers/did-youknow/sts. htm Sonia Philosoph-Hadas, Shimon Meir, Ida Rosenberger, and Abraham H. Halevy. 1996. Regulation of the Gravitropic Response and Ethylene Biosynthesis in Gravistimulated Snapdragon Spikes by Calcium Chelators and Ethylene lnhibitors’. Plant Physiol. 110: 301 -310 Săvulescu Elena. 2015. Botanică sistematică. Facultatea de Horticultură, București. Șelaru Elena. 2007. Cultura Florilor de Grădină. Editura Ceres, București. Toma Florin. 2010. Floricultură. Facultatea de Horticultură, București. International Student Symposium "Hortus Academicus“ March 31, 2017 - Bucharest, Romania