Cultivation of thyme for medicinal purposes should result in high dry-matter yield and sufficient active principals concentrations. In this experiment two methods of crop establishment were compared: direct sowing (final plant density: 100,000 plants/ha) and planting at two densities: D-1 (100,000 plants/ha) and D-2 (166,000 plants/ha). The use of transplants promoted growth and resulted in yields three times higher than direct sowing (3340 vs. 1002 kg dry matter/ha). There were significant differences in biomass between the two densities evaluated. Plants under D-1 weighed 33 g dry matter/plant vs. 22 g dry matter/plant for D-2. Hence, dry-matter yield per hectare was not affected by planting density. Active principals concentrations were not affected by treatments. So far, it is recommended that cultivation of thyme under Quebec's conditions be based on transplanting at moderate (100,000 plants/ha) density.
Lucette LaFlamme, Marie-Hélène Michaud, and Nicholas Tremblay
Lucette Laflamme, Nicolas Tremblay, and Marie-Hélène Michaud
Angelica is grown in Quebec (Canada) for its root-bound medicinal properties. Matol Botanique Int., a major user of Angelica extracts, decided 4 years ago to promote local production in order to secure supplies and quality. However, the crop has to be started from seed that show low and variable germination behavior. Emergence occurs after ± 12 days and most of the germination if obtained after 20 to 40 days depending on seed origin and test conditions. Maximum germination ranges from 6 to 57%. Three treatments were first compared in order to stimulate germination: seed soaking in warm water for 24 h, watering germination trays with algae extracts and placing floating row covers over the trays. Angelica germination was significantly improved only by row covers with a maximum of 24% vs 19%. Results were obtained from experiments with other techniques (stratification, seed conditioning, etc,...) to further improve germination.
2Working for the Horticultural Research Centre, Laval University, Que.
Marie-Hélène Michaud, Joseph Makhlouf, Nicolas Tremblay, and André Gosselin
A research project was undertaken in 1990 with the objective of improving both quality and productivity of peas, beans and sweet corn grown and processed in Quebec (Canada). It was conducted with the technical and financial help of five proccessing companies. Cultivar trials were undertaken as part of this project together with an evaluation of commercial practices in the areas of pest control, fertilization and crop management. Samples of fresh and processed products were analysed for nutritional quality and pesticide residues. During this presentation we will show preliminary results of the pesticide residue analyses and will compare fresh and processed products. So far, determination of dimethoate, trifluralin and bentazone (peas), azinphosmethyl and permetrin (beans) and cypermetrin (sweet corn) showed no concentration exceeding the Canadian norm (<0, 1mg/kg), with the exception of a bean field with azinphosmethyl residues. Canning and freezing operations greatly reduced pesticide residues so that all processed samples tested below detectable levels.
Nicolas Tremblay, Marie-Hélène Michaud, René Crête, and André Gosselin
With the increase in popularity of natural medicine there is an ever growing market for the production of medicinal plants. In the last decade, screening trials of a number of species were conducted. The species currently under study are: angelica (Angelica archangelica; biennial, roots harvested), thyme (Thymus vulgaris; perennial, shoot harvested), German chamomilla (Matricaria recutita; annual, flowers harvested), horehound (Marrubium vulgare; perennial, shoot harvested) and dandelion (Taraxacum officinale; considered as a biennial, roots harvested). In 1990 the species were grown on three soil types (clay-loam, sandy loam and histosol) with different fertilization and irrigation practices. In 1991 two distinct trials were undertaken. The first considered herbicide efficiency and planting density. The second dealt with «organic» management strategies. Depending on the species, treatments of compost amendment, plastic mulch and implantation techniques were compared.