19 research outputs found
Herbage nutritive value of binary- and multi-species swards relative to single-species swards in intensive silage systems
peer-reviewedThe nutritive value of sown binary- and multi-species grassland mixtures may differ from the values expected
based on single-species swards of their constituent species. Field plots were established in a split-plot design to
assess the nutritive value of binary- and multi-species mixtures compared to single-species swards of three grass
species and red clover (RC) (Trifolium pratense L.) managed for intensive silage production. The nutritive value of
grass–legume binary mixtures reflected the values of the constituent species grown on their own, and thus may
be predicted from monoculture values. The relatively low digestibility (dry matter digestibility [DMD]) and crude
protein (CP) content of the Italian ryegrass (Lolium multiflorum L.) sward compared to perennial ryegrass (Lolium
perenne L.) and timothy (Phleum pratense L.) suggests that it may have a limited role in binary- or multi-species
swards. Herbage nutritive value in the multi-species swards (Mix 1: perennial ryegrass, timothy, RC and white
clover [Trifolium repens L.]; Mix 2: perennial ryegrass, timothy, RC, ribwort plantain [Plantago lanceolata L.] and
chicory [Cichorium intybus L.] ) appeared to be influenced more by the presence of legumes than herbs. Compared
to perennial ryegrass, the multi-species swards had a slower rate of DMD decline prior to Cut 1, but subsequently
had lower DMD values at the mid-season harvests. Both multi-species mixtures exhibited DMD, water-soluble
carbohydrate (WSC) and CP values that would not have been predicted from their constituent species and thus
need to be measured on herbage from field plots growing these mixtures
Dissection of Combinatorial Control by the Met4 Transcriptional Complex
Loss of Met31 and Met32 abolishes all Met4-activated transcription, while only certain target genes, such as sulfate assimilation genes, depend on Cbf1 and Met28 for expression. Unlike Met4 and the other cofactors, Cbf1 remains promoter-bound under inducing and repressing conditions and helps to stabilize Met32, the main platform for Met4, at promoters