Duppong L M, Delate K, Liebman M, Horton R, Romero F, Kraus G, Petrich J, Chowdbury P K
L. Duppong, K. Delate, M. Liebman, and R. Horton, Department of Agronomy, Iowa State University, Ames, IA 50011; F. Romero, Department of Horticulture, Iowa State University, Ames, IA 50011; and G. Kraus, J. Petrich and P.K. Chowdbury, Department of Chemistry, Iowa State University, Ames, IA 50011. Contribution of the Dep. of Agronomy, Iowa State Univ. and the Leopold Center for Sustainable Agriculture. Paper no. 19753 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa.
Crop Sci. 2004;44(3):861-869.
Because of expanding markets for high-value niche crops, opportunities have increased for the production of medicinal herbs in the USA. An experiment was conducted in 2001 and 2002 near Gilbert, IA, to study crop performance, weed suppression, and environmental conditions associated with the use of several organic mulches in the production of two herbs, catnip (Nepeta cataria L.) and St. John's wort (Hypericum perforatum L. 'Helos'). Treatments were arranged in a completely randomized design and included a positive (hand-weeded) control, a negative (nonweeded) control, oat straw, a flax straw mat, and a nonwoven wool mat. Catnip plant height was significantly greater in the oat straw than the other treatments at 4 wk through 6 wk in 2001; at 4 to 8 wk in 2002, catnip plant height and width was significantly lower in the negative control compared with the other treatments. Catnip yield was significantly higher in the flax straw mat than all other treatments in 2001. In 2002, St. John's wort yields were not statistically different in any treatments. All weed management treatments had significantly fewer weeds than the non-weeded rows in 2002. Total weed density comparisons in each crop from 2 yr showed fewer weeds present in the flax straw and wool mat treatments compared with positive control plots. There was no significant weed management treatment effect on the concentration of the target compounds, nepetalactone in catnip and pseudohypericin-hypericin in St. John's wort, although there was a trend toward higher concentrations in the flax straw treatment.
由于高价值特色作物市场不断扩大，美国药用草本植物的生产机会增加。2001年和2002年在爱荷华州吉尔伯特附近进行了一项试验，以研究在两种草本植物猫薄荷（Nepeta cataria L.）和圣约翰草（Hypericum perforatum L. 'Helos'）生产中使用几种有机覆盖物时的作物表现、杂草抑制情况及环境条件。试验处理采用完全随机设计，包括一个阳性（人工除草）对照、一个阴性（不除草）对照、燕麦秸秆、亚麻秸秆席和无纺羊毛席。2001年第4周 至第6周，猫薄荷在燕麦秸秆覆盖下的株高显著高于其他处理；2002年第4周 至第8周，阴性对照中猫薄荷的株高和株幅显著低于其他处理。2001年，亚麻秸秆席覆盖下的猫薄荷产量显著高于所有其他处理。2002年，圣约翰草在任何处理下的产量均无统计学差异。2002年，所有杂草管理处理的杂草数量均显著少于不除草的行。两年中每种作物的总杂草密度比较显示，与阳性对照地块相比，亚麻秸秆和羊毛席处理中的杂草较少。尽管亚麻秸秆处理中有目标化合物浓度升高的趋势，但杂草管理处理对猫薄荷中的荆芥内酯和圣约翰草中的假金丝桃素 - 金丝桃素浓度没有显著影响。
