The accumulation of aluminum in the aboveground parts of green manure plants belonging to the Brassicaceae family

Abstract

Purpose. To determine the level of aluminum (Al) accumulation in plants of the Brassicaceae family, which are used in agriculture as green manure and are promising plants for soil phytoremediation. The following crops were the subject of the study: oilseed radish, variety ‘Kyianochka’ (Raphanus sativus L. var oleiformis Pars. ‘Kyianochka’), white mustard, variety ‘Soniachna’ (Sinapis alba L. ‘Soniachna’), winter rapeseed, variety ‘Horlytsia’ (Brassica napus L. ‘Horlytsia’), Sarepta mustard, variety ‘Zolotava’ (Brassica juncea (L.) Czern. ‘Zolotava’), winter turnip rape, variety ‘Oriana’ (Brassica campestris var. oleifera f. biennis D.C. ‘Oriana’), tyfon, variety ‘Fitopal’ (Brassica campestris var. oleifera f. biennis DC. ´ Brassica rapa L. ‘Fitopal’). Methods. The research was carried out in the M. M. Gryshko National Botanical Garden of the National Academy of Sciences of Ukraine (Kyiv). Plants grown as green manure crops for 56 days on grey forest degraded sandy loam soil, pH 6.5–7.0, were analysed. Aluminum content was determined using an inductively coupled plasma optical emission spectrometer (ICP­OES) ICAP 6300 Duo. The possibility of metal accumulation in plant tissues was assessed using the bioconcentration factor (BF). Results. Measurements showed the following content of Al in plant tissues (in abs. dry matter): oilseed radish, variety ‘Kyianochka’ – 2035.9 mg/kg, white mustard, variety ‘Soniachna’ – 687.5 mg/kg, winter rapeseed, variety ‘Horlytsia’ – 388.6 mg/kg, Sarepta mustard, variety ‘Zolotava’ – 1238.5 mg/kg, winter turnip rape, variety ‘Oriana’ – 1105.2 mg/kg, tyfon, variety ‘Fitopal’ – 854.4 mg/kg. Conclusions. Under growing conditions, the aluminum content in plants did not exceed 0.2%. All the samples studied have a BF < 1 and are not hyperaccumulators of the element according to this criterion. However, three of the investigated samples (‘Zolotava’ Sarepta mustard, ‘Oriana’ winter turnip rape and ‘Kyianochka’ oilseed radish) have an aluminum content in the above­ground dry matter of more than 1000 mg/kg, indicating a significant accumulation of this element. For the purposes of phytoextraction of aluminum, the most suitable of the plants studied is oilseed radish ‘Kyianochka’ (BF ≈ 0.4).