Planting density effects on root yield of purple coneflower (Echinacea purpurea (L.) Moench)

References

• Anonymous . 1986 . Cultivation of Echinacea . Heil und Gewürzpflanzen , 31
   Google Scholar
• Bauer , R. and Wagner , H. 1991 . “ Echinacea species as potential immunostimulatory drugs. ” . In Economic nd medicinal plant research , Edited by: Wagner , H. and Farnsworth , N. R. (Volume 5) , 253 – 317 . New York : Academic Press .
   Google Scholar
• von Bomme , U. , Hölzl , J. , Heßler , C. and Stahn , T. 1992a . Wie beeinflußt die sorte wirkstoffgehalt und ertrag von Echinacea purpurea (L.) Moench im hinblick auf die pharmazeutische nutzung? 1. Mitt.: Ergebnisse des einjahrigen anbaues . Landwirtschaftliches jarbuch , 69 (2) : 149 – 164 .
   Google Scholar
• von Bomme , U. , Hölzl , J. , Heßler , C. and Stahn , T. 1992b . Wie beeinflußt die sorte wirkstoffgehalt und ertrag von Echinacea purpurea (L.) Moench im hinblick auf die pharmazeutische nutzung? 2. Mitt.: Ergebnisse des zweiten standjahres und gesamtbeurteilung. . Landwirtschaftliches jarhuch , 69 (3) : 323 – 342 .
   Google Scholar
• DSIR . 1968 . General survey of the soils of the South Island , New Zealand Soil Bureau bulletin 27 New Zealand
   Google Scholar
• Foster , S. 1991 . Echinacea, nature's immune enhancer , Rochester, , VT : Healing Arts Press .
   Google Scholar
• Fry , W. E. 1982 . Principles of plant disease management , New York : Academic Press .
   Google Scholar
• George , N. 1990 . “ Medicinal plants: potential for New Zealand ” . In Internal report of the Ministry of Agriculture and Fisheries , Lincoln : MAFTech .
   Google Scholar
• Harper , J. L. 1977 . Population biology of plants , London : Academic Press .
   Google Scholar
• Hewitt , A. E. 1992 . New Zealand soil classification. , DSIR land resources scientific report no. 19 Lower Hutt : DSIR Land Resources .
   Google Scholar
• Hobbs , C. B. 1989 . The Echinacea handbook , Capitola : Botanica Press .
   Google Scholar
• Hobbs , C. B. 1994 . Echinacea, a literature review. . Herbalgram , 30 : 33 – 47 .
   Google Scholar
• van Klink , J. W. and Perry , N. B. 1994 . Echinacea analyses. 2. Identification of further alkamides, comparison of analytical methods, and roots vs rhizomes. Internal report , Dunedin : New Zealand Institute for Crop & Food Research Ltd. .
   Google Scholar
• McCullagh , P. and Neldor , J. A. 1989 . Generalized linear models , (2nd edition) , London : Chapman and Hall .
   Google Scholar
• Mountier , N. S. , Grigg , J. L. and Ooman , G. A. C. 1966 . Sources of error in soil tests. . New Zealand journal of agricultural research , 9 : 328 – 338 .
   Web of Science ®Google Scholar
• New Zealand Meteorological Service . 1983 . Summaries of climatological observations to 1980 , New Zealand meteorological service miscellaneous publication no. 177
   Google Scholar
• Olsen , S. R. , Cole , C. V. , Watanabe , E. S. and Dean , L. A. 1954 . Estimation of available phosphorous in soils by extraction with sodium bicarbonate , United States Department of Agriculture circular 939
   Google Scholar
• Parmenter , G. , Burgmans , J. , Burton , L. , Douglas , M. , Follett , J. , Gray , G. and Smallfield , B. 1992 . Production of the medicinal crops Valerian and Echinacea in New Zealand. . Proceedings of the Agronomy Society of New Zealand , 2 : 61 – 65 .
   Google Scholar
• Perry , N. B. , van Klink , J. W. , Burgess , E. J. and Parmenter , G. A. 1997 . Alkamide levels in Echinacea purpurea (L.) Moench: a rapid analytical method revealing differences among roots, rhizomes, stems, leaves and flowers. . Planta medica , 63 : 58 – 62 .
   PubMed Web of Science ®Google Scholar