Abstract

As a result of an increase in the urban demand for organic horticultural products, locally available soil amendments need to be evaluated. Here, the effects on growth and reproductive output of Cucurbita pepo, were assessed for the aquatic invasive Eichornia crassipes, a commercially produced vermicompost, and chicken manure. In addition, their effects were contrasted with those of a Nitrogen (N) dose-response experiment that was used for standardization of plant responses. In general, higher N doses yielded a greater reproductive output. For instance, the high N concentrations of 3.2 and 8 mM yielded over 50% more flowers that were also about three times larger than those from the lower doses. While chicken manure inhibited seed germination for C. pepo, transplanted individuals treated with this soil amendment were the only ones to produce female flowers. In addition, a greater number of male flowers (4-fold greater) that were substantially (3.3-fold by dry mass) heavier than the control resulted from this amendment. Plants fertilized with vermicompost produced twice as many flowers than the control, and were 43% heavier. In turn, the plants fertilized with E. crassipes tended to be similar to the control.

Key words: Chicken manure, invasive species control, organic fertilizer, vermicompost, water hyacinth.