Author
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Skinner, Robert |
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Gustine, David |
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Submitted to: Agronomy Abstracts
Publication Type: Abstract Only Publication Acceptance Date: 10/30/2001 Publication Date: 10/30/2001 Citation: SKINNER, R.H., GUSTINE, D.L. FREEZING TOLERANCE OF PASTURE SPECIES GROWING IN DIVERSE MIXTURES. AGRONOMY ABSTRACTS. 2001. CD-ROM. Interpretive Summary: Technical Abstract: Growing forages in multi-species mixtures rather than as monocultures often reduces the susceptibility of sensitive species to environmental stress. We examined the effects of mixture complexity (monocultures vs. five- species mixtures) and drought stress prior to freezing on the freezing tolerance of six pasture species from three functional groups (grasses, legumes, and forbs). Growth chamber-grown seedlings were subjected to three drought stress cycles, then cold hardened at near freezing temperatures for three weeks. Chamber temperature was reduced to -14 degrees C for 3 h, then survival was determined after a three week recovery period. Drought stress reduced the freezing tolerance of both legumes in the study (alfalfa and white clover), increased the tolerance of orchardgrass and plantain, and had no effect on timothy or chicory. The freezing tolerance of white clover, orchardgrass, and timothy decreased when these species were planted in complex mixtures rather than as monocultures. There was no evidence that increasing mixture complexity reduced susceptibility to freezing stress. |
