FORAGE PLANT CELL WALLS FIBER COMPONENTS CONTENT AND DIGESTIBILITY OF NEW VARIETIES PERENNIAL GRASSES IN THE VEGETATION

Y. Naydenova, A. Katova, A. Petrov

Резюме: The forage plant cell walls fiber components, determining energy feeding value and enzyme in vitro digest¬ibility as the main forage quality characteristics are variable in the vegetation. The aim of the study is to establish the changes in plant cell walls fiber components content – poliosides and lignin and enzyme in vitro degradability (digestibility) of new registered perennial grass varieties in OECD list, Official variety list of the Republic of Bulgaria as well as perennial grass breeding populations. The perennial grass species and varieties present high forage quality in pasture development stage. Changes in forage quality appeared forward vegetation process but they have different temp. Tetraploid perennial ryegrass populations remains high quality forage for the longest period in the first spring growth which allow enlarged pasture period near to a month.
The tetraploid perennial ryegrass breeding population NBG demonstrates the best forage quality characteris¬tics in comparison with other studied species and varieties. Pasture stage forage fiber components, lignification and digestibility are presented as follow: 2012: NDF 53.70%, ADF 28.2%, ADL 2.77%, Lignification 5.2 and IVDMD 76.54 and for 2013 respectivelly: 46.60%, 24.16%, 1.07%, coeff. 2.3, 81.61%. Flowering stage forage fiber components, lignification and digestibility are presented as follow: 2012: NDF 54.5%, ADF 29.97%, ADL 2.8%, Lignification 5.1 and IVDMD 71.88% and for 2013 respectivelly: 60.24%, 45.14%, 3.66%, coeff. 6.1, 54.42%.
The tetraploid perennial ryegrass breeding population SBG demonstrates faster changes in forage quality characteristics because it is the earliest in maturity. Pasture stage forage fiber components, lignification and di¬gestibility are presented as follow: 2012: NDF 55.4%, ADF 30.65%, ADL 3.25%, Lignification 5.9 and IVDMD 67.94% and for 2013 respectivelly: 44.27%, 24.1%, 1.2%, coeff. 2.7, 81.66%. Flowering stage forage fiber com¬ponents, lignification and digestibility are presented as follow: 2012: NDF 56.08%, ADF 32.67%, ADL 3.89%, Lignification 6.9 and IVDMD 62.96% and for 2013 respectivelly: 60.90%, 37.00%, 4.49%, coeff. 7.4, 52.63%.
Forage quality for two wheatgrass varieties has higher values of plant cell walls fiber components content and lower digestibility in comparison with perennial ryegrass. Desert wheatgrass Morava in the vegetation process present higher values of plant cell walls fiber components content and lower digestibility in comparison with diploid crested wheatgrass Svejina.

Ключови думи: fibers; forage quality; in vitro digestibility; new perennial grass species and varieties

Дата на публикуване: 2017-03-15