Influence of biostimulants on phenolic content in broccoli heads directly after harvest and after storage

Abstract

Biostimulants are commonly used in horticulture, primarily to increase yield quantity and quality, as well as plant tolerance to stress. The purpose of the study was to determine the effect of amino acid-based biostimulants and amino acids in combination with Ascophyllum nodosum filtrate, applied during the growing season on the phenolic content in broccoli heads both after harvest and after long storage in a cold store. The seedlings were planted in mid-July, and heads were harvested from September to October in each year of the study. Ascophyllum nodosum filtrate at a concentration of 1% was used during seedling production. The plants were watered with biostimulants twice, in the fourth and fifth week after sowing. They were also sprayed with amino acid-based biostimulants (1.5 dm 3 ha -1) three times, i.e. after the second, fourth and sixth week after planting. The biostimulants were not used in the control treatment. After harvest, the heads were stored for three weeks in a cold store at 1-2°C and 95% RH. Chemical analyses of total phenolic, caffeic, ferulic and sinapic acids, and of quercetin and kaempferol were carried out on samples of fresh broccoli and after the first, second and third week of storage. It was found that the application of biostimulants resulted in a significant increase in the total phenolic content, sinapic acid content, as well as quercetin content. Both in the control treatment and in the plants treated with the biostimulants, the concentration of all the tested phenolic compounds increased with the duration of storage.Ke y wor d s: amino acids, Ascophyllum nodosum filtrate, Brassica oleracea var. italica, kaempferol, phenolic acids, quercetin

Bioactive properties of greenhouse‐cultivated green beans (Phaseolus vulgaris L.) under biostimulants and water‐stress effect

“…However, this increasing trend was not consistent throughout the years, and the authors suggested a combined effect of growing conditions and biostimulants application, whereas the beneficial effect of seaweed filtrates on total phenols content was attributed to osmotic stress induced by the high content of A. nodosum filtrates in mannitol. 34 Similar results have been reported for total phenols and flavonoids contents of soybean seeds after the application of two synthetic biostimulants (Atonik and Tytanit), where, despite the different response being observed during a 3 year study, the application of biostimulants in a high single doses gave consistently the best results. 9 Polyphenols and flavonoids content of seeds from three soybean cultivars was also affected by natural biostimulants application such as Fylloton (a complex of amino acids and seaweed extracts) in a dose and cultivar-dependent manner.…”

“…The same trend was observed in our study, where a decrease in total phenolic compounds content was observed between pods of different harvests for normally irrigated or water‐stressed plants with no biostimulant use. In contrast, Kałużewicz et al . observed an increase of total phenols, phenolic acids, quercetin, and kaempferol content in broccoli heads after the application of an amino‐acid‐based biostimulant and/or a combination of amino‐acid‐based biostimulant with Ascophyllum nodosum filtrates.…”

“…observed an increase of total phenols, phenolic acids, quercetin, and kaempferol content in broccoli heads after the application of an amino‐acid‐based biostimulant and/or a combination of amino‐acid‐based biostimulant with Ascophyllum nodosum filtrates. However, this increasing trend was not consistent throughout the years, and the authors suggested a combined effect of growing conditions and biostimulants application, whereas the beneficial effect of seaweed filtrates on total phenols content was attributed to osmotic stress induced by the high content of A. nodosum filtrates in mannitol . Similar results have been reported for total phenols and flavonoids contents of soybean seeds after the application of two synthetic biostimulants (Atonik and Tytanit), where, despite the different response being observed during a 3 year study, the application of biostimulants in a high single doses gave consistently the best results .…”

“…33 The same trend was observed in our study, where a decrease in total phenolic compounds content was observed between pods of different harvests for normally irrigated or water-stressed plants with no biostimulant use. In contrast, Kału̇zewicz et al 34 observed an increase of total phenols, phenolic acids, quercetin, and kaempferol content in broccoli heads after the application of an amino-acid-based biostimulant and/or a combination of amino-acid-based biostimulant with Ascophyllum nodosum filtrates. However, this increasing trend was not consistent throughout the years, and the authors suggested a combined effect of growing conditions and biostimulants application, whereas the beneficial effect of seaweed filtrates on total phenols content was attributed to osmotic stress induced by the high content of A. nodosum filtrates in mannitol.…”

Biostimulants and Microorganisms Boost the Nutritional Composition of Buckwheat (Fagopyrum esculentum Moench) Sprouts

“…There are currently 48 biological control agents registered for use in Europe, including fungi, oomycetes, and bacterial microorganisms [9]. Numerous studies demonstrated their highly positive effect on plants [10][11][12]. Seed inoculation with the endophytic bacterium Herbaspirillum ST-B2 enhanced growth of sprouts and microgreens, promoted root elongation, and increased mass production of sprouts [13].…”