ARS | Publication request: CUPHEA SEED AND OIL YIELD RESPONSE TO HARVEST DATE

Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: November 4, 2004
Publication Date: November 4, 2004
Citation: Gesch, R.W., Cermak, S.C., Isbell, T., Forcella, F. 2004. Cuphea seed and oil yield response to harvest date [CD-ROM]. ASA-CSSA-SSSA Annual Meeting Abstracts. Madison, Wisconsin.

Technical Abstract: Cuphea can serve as a domestic oilseed crop replacement for small and medium-chain triglycerides used in chemical manufacturing. Present domesticated germplasm is indeterminate and seeds tend to shatter if plants are left in the field too long. Therefore, a field study was conducted to determine the best harvest time to obtain greatest seed yield and oil content. Cuphea (PSR23) was sown May 14 in 2001 and 2002 in west central Minnesota and harvested at one to two week intervals from mid Aug. to mid Oct. Modeling results from both years indicated that seed yield increased at a rate of about 5.3 kg ha**-1 d**-1 between Sept. 1 and Oct. 6, but declined thereafter at a rate of about 11.6 kg ha**-1 d**-1 primarily due to shattering. Seed oil content followed a sigmoidal response pattern to harvest date, increasing rapidly from 24 to about 31% throughout early to late Sept. and remaining stable thereafter. Greatest seed yields and oil content were obtained over about a 15 d-period between late Sept. and early Oct. Further agronomic and genetic research is needed to optimize harvest management of cuphea to reduce yield loss to seed shattering.