Technical Abstract:
The manufacturing of many industrial chemicals relies on medium-chain fatty acids (MFAs) derived from petroleum and coconut and palm kernel oils. Currently, there are no temperate-climate/short-season crops available to meet the industry's demands. However, seed from the plant Cuphea (waxweed), which is native to North America, produces a large amount of MFAs and shows spotential for domestication. Seed of Cuphea obtained from Dr. Steven Knapp at Oregon State University is being used to conduct a series of experiments to examine basic management practices for optimizing yield in the upper Midwest and exploring environmental effects on plant growth and development. A field study was initiated in the summer of 1999 to determine optimum planting date and row spacing for seed yield. Five dates ranging from April 15 to June 15 and four row spacings from 0.125 to 0.5 m wide are being used for this study. Planting in May and harvesting in August resulted in maximum seed yield (as high as 1 Mg ha**-1). Yield declined as much as 27 and 56% with earlier and later planting dates, respectively. Also, yield increased with row spacing up to 0.5 m. Wider rows resulted in greater branching and subsequent filled-pod numbers per plant. Controlled environment experiments showed that the temperature requirement for Cuphea seed germination was similar to that of soybean cultivars grown in this region, but only when sown at a soil depth no greater than 1 cm. Commercialization of Cuphea is still at an early stage. However, our results indicate that it can be successfully cultured in cool temperate environments with short growing seasons.