Optimisation of Transplant Age in Combination with Dark-chilling to Enhance the Biological Quality of Broccoli Cultivated in Summer



Under field conditions, crops are exposed simultaneously to more than one environmental stress factor. Controlled abiotic stress applied at the transplant stage can be used as a tool for inducing stress memory, improving stress tolerance after transplanting, and enhancing the nutraceutical value of the yield. The aim of present study was to determine the effect of dark-chilling at 2 °C for 1 and 2 weeks on the tolerance of broccoli seedlings of various ages against adverse conditions in the field and the chemical composition of the inflorescences. Two separate planting programmes were undertaken in the summer. In general, planting delay by about 1 month resulted in an increase in dry weight of about 3%, ascorbic acid (38%), soluble sugars (18%), K (14%), P (13%), Zn (12%), Fe (8%), and Mn (9%) in broccoli inflorescences. Planting of young, 4-week-old seedlings resulted in higher ascorbic acid content in broccoli inflorescences of about 15%, soluble sugars (7%), K (5%), P (6%), Mg (4%), Na (11%), and Zn (3%) in broccoli inflorescences as compared to 10-week-old ones. Chilling of seedlings for two weeks caused an increase in dry weight in broccoli inflorescences of about 6%, ascorbic acid (15%), soluble sugars (12%), K (2%), P (2%), Mg (5%), Zn (3%), Fe (4%), and Mn (6%) as compared to the non-chilled control. The results indicated that the age of the seedlings and dark-chilling influenced the level of chemicals related to taste and biological value of broccoli inflorescences in a complex way. There was no general superiority or interaction of any of the experimental factors affecting all health-related compounds. Dark-chilling can be considered as a practice of broccoli seedling management before transplanting, positively affecting some yield parameters through stress memory induction.


Brassica oleracea var. italica; chemical compounds; inflorescences; stress memory

Full Text:



Bruce TJA, Matthes MC, Napier JA, Pickett JA (2007). Stressful “memories” of plants: evidence and possible mechanisms. Plant Science 173(6):603-608.

Cakmak I (2008). Role of mineral nutrients in tolerance of crop plants to environmental stress factors. In: Imas P, Price MR (Eds). Fertigation: optimizing the utilization of water and nutrients, International Symposium on Fertigation. Beijing, China pp 35-48.

Couée I, Sulmon C, Gouesbet G, El Amrani A (2006). Involvement of soluble sugars in reactive oxygen species balance and responses to oxidative stress in plants. Journal of Experimental Botany 57(3):449-459.

Fabek S, Toth N, Radojcic Redovnikovic I, Herak Custic M, Benko B, Zutic I (2012). The effect of nitrogen fertilization on nitrate accumulation, and the content of minerals and glucosinolates in broccoli cultivars. Food Technology and Biotechnology 50(2):183-191.

FAO (2016). FAOSTAT. FAO, Rome, Italy. Retrieved 2018 Feb 02 from http://www.fao.org/home/en/.

FAO (2006). World Reference Base for Soil Resources. FAO, Rome, Italy. Retrieved 2017 Oct 09 from http://www.fao.org/home/en/.

Grabowska A, Kunicki E, Kalisz A, Wojciechowska R, Leja M, Sekara A (2014). Chilling stress applied to broccoli transplants of different age affects yield of the plants cultivated in summer. Horticultural Science (Prague) 41(2):71-79.

Grabowska A, Sekara A, Bieniasz M, Kunicki E, Kalisz A (2013). Dark-chilling of seedlings affects initiation and morphology of broccoli inflorescence. Notulae Botanicae Horti Agrobotanici Cluj-Napoca 41(1):213-218.

Jackson KW, Qiao H (1992). Atomic-absorption, atomic emission, and flame emission-spectrometry. Analytical Chemistry 64:R50-R66.

Jahangir M, Abdel-Farid BI, Kim HK, Choi YH, Verpoorte R (2009). Healthy and unhealthy plants: The effect of stress on the metabolism of Brassicaceae. Environmental and Experimental Botany 67:23-33.

Jeffery EH, Araya M (2009). Physiological effects of broccoli consumption. Phytochemical Reviews 8:283-298.

Kalisz A, Sekara A, Cebula S, Grabowska A, Kunicki E (2014). Impact of low-temperature transplant treatment on yield and quality of cauliflower curds in late spring production. Scientia Horticulturae 176:134-142.

Kalisz A, Sekara A, Grabowska A, Cebula S, Kunicki E (2015). The effect of chilling stress at transplant stage on broccoli development and yield with elements of modeling. Journal of Plant Growth Regulation 34:532-544.

Kaluzewicz A, Bosiacki M, Fraszczak B (2016). Mineral composition and the content of phenolic compounds of ten broccoli cultivars. Journal of Elementology 21(1):53-65.

Kaymak HC, Yarali F, Guvenc I (2009). Effect of transplant age on growth and yield of broccoli (Brassica oleracea var. italica). Indian Journal of Agricultural Sciences 79:972-975.

Moreno DA, Carvajal M, Lopez-Berenguer C, Garcia-Viguera C (2006). Chemical and biological characterisation of nutraceutical compounds of broccoli. Journal of Pharmaceutical and Biomedical Analysis 41(5):1508-1522.

Pastori GM, Foyer CH (2002). Common components, networks, and pathways of cross-tolerance to stress. The central role of “redox” and abscisic acid-mediated controls. Plant Physiology 129(2):460-468.

Raseetha S, Leong SY, Burritt DJ, Oey I (2013). Understanding the degradation of ascorbic acid and glutathione in relation to the levels of oxidative stress biomarkers in broccoli (Brassica oleracea L. italica cv. Bellstar) during storage and mechanical processing. Food Chemistry 138:1360-1369.

Rogers HJ (2012). Is there an important role for reactive oxygen species and redox regulation during floral senescence? Plant, Cell & Environment 35(2):217-233.

Rosa E, David M, Gomes MH (2001). Glucose, fructose and sucrose content in broccoli, white cabbage and Portuguese cabbage grown in early and late seasons. Journal of the Science of Food and Agriculture 81:1145-1149.

Sato F, Yoshioka H, Fujiwara T, Higashio H, Uragami A, Tokuda S (2004). Physiological responses of cabbage plug seedlings to water stress during low-temperature storage in darkness. Scientia Horticulturae 101(4):349-357.

Taspinar S, Dumlupinar R, Demir F, Cakmak T, Gülen Y (2009). Determination of chilling temperature effects on nutrient elements composition and distribution in cole (Brassica oleracea L. cv. Acephala) using the WDXRF spectroscopic technique. African Journal of Biotechnology 8:6569-6575.

Todorova D (2011). Effect of transplant age on the productive behaviors of broccoli Brassica oleracea var. italica Plenck. Plant Science 48:223-226.

Van den Ende W, Valluru R (2008). Sucrose, sucrosyl oligosaccharides, and oxidative stress: scavenging and salvaging? Journal of Experimental Botany 60(1):9-18.

Valluru R, Van den Ende W (2008). Plant fructans in stress environments: emerging concepts and future prospects. Journal of Experimental Botany 59:2905-2916.

Vasanthi HR, Mukherjee S, Das DK (2009). Potential health benefits of broccoli - a chemico-biological overview. Mini-Reviews in Medicinal Chemistry 9(6):749-759.

Xie J, Gao Z, Swisher M, Zhao X (2016). Consumers’ preferences for fresh broccolis: interactive effects between country of origin and organic labels. Agricultural Economics 47:181-191.

Yemm EW Willis AJ (1954). The estimation of carbohydrates in plant extracts by anthrone. Biochemical Journal 57:508-514.

DOI: http://dx.doi.org/10.15835/nbha46211073

June 1, 2017: Notulae Botanicae Horti Agrobotanici Cluj-Napoca in CiteScore rank (Scopus – Elsevier) 28/66 in Horticulture