ABSTRACT
Flowering is a crucial phase in hemp cultivation. It influences both stem and seed yield. A uniform and short flowering duration in hemp is desirable, because it favors uniform crop development. Moreover, flowering is often taken as a reference point for harvesting, and very long durations of flowering might mislead the operator in judging the proper time for mowing. In this article, a large dataset of flowering time and duration for different monoecious and dioecious varieties was studied and the effect of sowing time and genotype on flowering duration is discussed. Minimal flowering duration was observed when the time from emergence to flowering was short. This, was related however, to low yields. Dynamics of flowering was accurately described by a bi-logistic curve that indicates the presence of two underlying logistic processes.
KEYWORDS:
The financial support for the field experiments was granted by the Italian Ministry of Agricultural and Forestry Policies and the European Commission. The authors would like to acknowledge all the students involved in the difficult and time-consuming operation of flowering count, with particular thanks to M. Errani, S. Scicchitano, F. Pelatti, and P. Lafabiana.
Notes
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Venturi, G., Amaducci, S. 2004. Hemp: An ancient crop considered in a modern perspective. Supplemento a “I Georgofili. Atti dell'Accademia dei Georgofili” Anno 2003, Settima serie, Vol. L:17–64. (In Italian).