Influence of 5-aminolevulinic acid on physiological and biochemical characteristics of winter wheat varieties with different levels of anthocyanins in coleoptiles

Physiological and biochemical characteristics of two varieties of winter wheat seedlings with red (Et W5) and green (Vladi) coleoptiles have been studied. Variety Et W5 with high content of anthocyanins (on average 412 ± 52 μmol/g fr wt), chlorophylls (Chl) and carotenoids and a low level of heme and proline in coleoptiles had high frost resistance (88 % of surviving plants exposed to temperatures of ‒8 °C for 5 h at the age of 7 days) and a high ability to continue growth and development after undergoing cooling. Variety Vladi with a low content of anthocyanins (on average 12.5 ± 1.2 μmol/g fr wt), Chl and carotenoids, but a higher level of heme and proline in coleoptiles compared to varieties Et W5 had low level of frost resistance (80 % of surviving plants) and was characterized by a low ability to continue growth and development after undergoing cooling. Soaking wheat seeds in a solution of exogenous ALA (50 mg/l) for 2 h before sowing increased the germination of seeds of both varieties, enhanced the length of plants of the Et W5 variety by 10 %, 1.4 times the content of anthocyanins in the coleoptiles of this variety plants and also increased their frost resistance up to 97 %. Under action of ALA frost resistance of Vladi seedlings increased up to 93 %.