Quantitative study on medicinal plants used for the treatment of respiratory diseases in chontales of Nacajuca, Tabasco, Mexico

The results of an evaluation of the traditional knowledge of the use of medicinal plants for the treatment of respiratory diseases among the inhabitants of five communities of Nacajuca, Tabasco, Mexico are presented. The study was conducted using ethnobotanical methods applied to 26 key informants. A total of 22 species used for respiratory diseases were recorded. Of the informants, 61.5% are traditional doctors, recognized by the people, the rest are people who only use them at home. Of these, the species that had the greatest relative importance due to their frequency of mention in the interviews were the Jícara (Crescentia cujete), the toad grass (Epaltes mexicana), the purple maguey (Tradescantia spathacea) and the elderberry (Sambucus mexicana). The part that they use the most are the leaves as tea. 77% grow them within their home gardens, others collect them in the field and only one buy them in the markets. Of the species reported for respiratory problems, most have other uses, being also ornamental, edible and timber. The greater participation of women is observed during the study, since they are the head of the family and have knowledge of the use of medicinal plants for lung diseases. This shows that traditional medicine continues to be of great importance for Chontal communities in solving respiratory problems.

What is Sambucus mexicana (Adoxaceae)?

Inconsistent application of the name Sambucus mexicana C. Presl ex DC. has resulted in confusion in the literature and in herbaria. In order to determine the correct application of the name, Presl’s original material (a Haenke collection, made on the Malaspina Expedition) was located and characterized. It matches plants from the area around Monterey, California, where Haenke did much collecting, and clearly differs from Sambucus taxa in other parts of North America. The name S. mexicana must be applied to plants from California and adjacent areas, as has been done by most authors, not to plants from central Mexico, as in a few recent references. A lectotype is designated for the species.

Development of In-ground Container Plants of Mexican Elders Exposed to Drought

Mexican elder (Sambucus mexicana Presl.) is used in arid landscapes of the Southwest, but the plant is known for its unpredictable performance in those landscapes. We studied drought responses of mexican elder plants grown in an arid environment using an in-ground nursery production system. Plants were maintained as well-irrigated controls or exposed to cyclic drought and irrigated based on evapotranspiration. Drought treatment lasted 165 days. Plants exposed to drought had more negative predawn and midday water potentials than well-watered plants. The ratio of variable to maximal fluorescence (Fv/Fm) for the drought group (0.76), was near the optimum value of 0.8, suggesting that chloroplasts of drought-stressed plants maintained high levels of activity. Drought cycle, but not drought treatment affected stomatal conductance. Drought-stressed plants had lower transpiration rates than controls except at drought cycle five when transpiration rates were similar between irrigation treatments. Relative water content was higher in controls (76%) than plants exposed to drought (66%). Leaf area of well-irrigated plants was over four times higher than that of plants exposed to drought. Leaf area to root dry weight ratio of drought-stressed plants was 79% lower than control plants. Severely reduced leaf area of drought-stressed plants might be one reason why landscape personnel conclude that mexican elder plants perform poorly in arid landscapes.

A System to Measure Evapotranspiration of In-ground Container Plants of Mexican Elder

Accurate measurement of evapotranspiration (ET) is difficult and expensive for large, in-ground container (pot-in-pot) plants. We engineered and used a simple and inexpensive system to determine evapotranspiration of in-ground container trees. The system was shop-assembled and used a block and tackle system attached to a collapsible tripod. A unique container harness system attached to the block and tackle system was used to lift containers that were sunken in the ground. Containers were weighed with a battery-operated balance that was accurate to 1 g (0.04 oz) at its maximum load capacity of 60 kg (132.3 lb). One person operated the system, and the weight of the system exclusive of the balance was 17.5 kg (38.50 lb). Gravimetric water use data obtained with the system werecombined with meteorological data to compute crop coefficients (Kc) of mexican elder (Sambucus mexicana). The system detected small changes in daily water use of mexican elder trees grown in 76-L (20-gal) in-ground containers. Crop coefficients ranged from 0.17 to 0.71. The acquisition of evapotranspiration data from relatively large, containerized landscape plants may be facilitated because the system is simple, inexpensive, and accurate.