The effects of growth regulators on spring barley (Hordeum vulgare L.) morphological indicators and grain contamination with fungi and mycotoxins
Lithuanian Institute of Agriculture, Instituto str. 1, LT–58344 Akademija, Kedainiu distr.,Lithuania; e-mail: skaidre@lzi.lt, ona@lzi.lt,
Abstract:
The effects of growth regulators Modus 250 EC (trinexapac–ethyl 250 g l-1) and Cerone 480 (etefon 480 g l-1) on the morphological characteristics of the spring barley varieties Henni and Luokė and on grain contamination with fungi and mycotoxins were studied at the Lithuanian Institute of Agriculture in 2004 and 2005.Spring barley was sprayed with the retardant Modus at growth stages 32–33 BBCH andwith the retardant Cerone at – 39–43 BBCH. Plant morphological measurements were made before harvesting. Percent of internal grain contamination with fungi was determined. The concentrations of the mycotoxins deoxynivalenol (DON), T-2 toxin and zearalenone (ZEN) in grain were measured by ELISA method, using Neogen diagnostic mycotoxin determination tests.The retardants reduced plant height from 66.0 to 58.0 cm, length of the last node from19.4 to 17.9 cm for the variety Henni, and from 74.1 to 63.8 cm, and from 22.4 to 16.9 cm, respectively, for the variety Luokė compared with the unsprayed plants.The content of Fusarium-affected grain in the retardant-sprayed and not appliedtreatments was similar, however, Fusarium avenaceum (Fr.) Sacc was more prevalent in the barley sprayed with retardants. F. avenaceum, F. sporotrichioides Sherb., F. poae (Peck) Wollenw, F. tricinctum (Corda) Sacc., F. culmorum (W. G. Smith) Sacc. dominated in the grain samples in 2005.The contents of DON, ZEN and T-2 toxin determined were low, however, higher contentswere identified for barley sprayed with the retardants.
Key words:
barley, fungi, mycotoxins, plant growth regulators