While weather is not appropriate for cassava planting, growers in the State of São Paulo, usually keep their planting material (stems) stored in different ways. It is used the horizontal or vertical heaping systems, being the first one more common. The use of the fresh-harvested stem for planting is rare. The objective of this work was to evaluate the storage systems, and none storage, of cassava (Manihot esculenta Crantz) stems on some agronomic and physiological aspects. Two cultivars and three types of cuttings were used in a 2 x 3 factorial experiment in a randomized block design with four replications. The cultivars used were IAC 12-829 and SRT 1287-Fibra, with high and low ability of branching, respectively. The types of cuttings were originated from fresh-harvested stems and from stems stored for 105 days period in horizontal and vertical heaping systems. The experiment was carried out during the 1991/1992 season, at the Vale do Paranapanema Experimental Station, Instituto Agronômico de Campinas, Assis, State of São Paulo, Brazil, in a Allic Dark Red Latosol, medium texture. The results showed that: (a) the storage of the stems in horizontal position lead to an increase in the number of primary shoots of the two varieties and increased the weight of the aerial part of the SRT 1287-Fibra; (b) SRT 1287-Fibra cultivar was more influenced by the horizontal storage than the IAC 12-829; (c) IAC 12-829 had superior root production, without differing from the SRT 1287-Fibra when the cuttings were derived from the horizontal storage stems; (d) the storage in the vertical position had a similar behaviour as the fresh-harvested stems.
cassava; Manihot esculenta Crantz; stem storage; shoot number; root and aerial part production