Desenvolvimento e produtividade de hastes florais Heliconia spp. cultivadas a pleno sol

Abstract

The genus Heliconia, belonging to the Heliconiaceae family, has approximately 250 species distributed predominantly from southern Brazil to northern Mexico. The genus has great potential for commercialization as cut flowers and a great morphological diversity to be explored in floriculture. The objective of this work was to follow the development and productivity of Heliconia spp. cultivated in full sun conditions of the Zona da Mata of the state of Pernambuco for indication of superior genotypes for cultivation and improvement programs. The data used are from an experiment carried out between December 2003 and August 2006, at the Helicônia Germplasm Active Bank of the Federal Rural University of the State of Pernambuco (BAGH - UFRPE), with a randomized block design consisting of 16 genotypes, four replications each. The genotypes were evaluated weekly, during 31 months, for the following characteristics: Days for inflorescence emission (DEI); Days to flower stem harvest (DCH); Total cycle (CYCLE); Number of leaves on flowering stem (NFH); Number of flower stems produced (N) per genotype; Number of flower stems harvested/month/clump (HPC); Flower stem fresh mass (FM); Flower stem diameter 20 cm below the inflorescence (DH); Flower stem length (CH); Inflorescence length (CI). To evaluate the results, the genotypes were grouped into small, medium and large sizes, and the data collected for the cited characters were analyzed monthly in a descriptive way. The average number of stems harvest/month/clump (NHM) was grouped into two cycles: 1st Cycle - 8 to 19 months after planting; and 2nd Cycle - 20 to 31 months after planting. With these data, statistical analyzes were carried out and the production of floral stems per hectare per year (PHF ha-1/year) was estimated in each cycle. For this purpose, an ANAVA was performed and the means were compared using the Tukey test at 5% probability, and were carried out in the treatments with four replications. The results of the descriptive analysis demonstrate that the evaluated genotypes present qualitative characteristics to be used as cut flowers, however they present differences regarding the cycle and production of floral stems that must be taken into account for the indication for use in floriculture. Statistical analysis showed a significant difference between the small and large genotypes for the number of stems harvest/month/clump in the 1st and 2nd cycle. For the small genotypes, a downward tendency in the production of flower stems was observed from June to August, the rainiest period in the region. For the small genotypes, H. psittacorum x H. spathocircinata cv. Golden Torch was the most productive, with 126 and 204 stems harvested/clump in the 1st and 2nd cycle, respectively. Among the medium-sized genotypes, H. latispatha cultivars showed seasonality, with a marked reduction in stem production from September to November, cv. Red Yellow Gyro producing only 0.67 stem and cv. Distans 5.25 stems per clump in October 2005. The number of stems harvested/clump in the 1st and 2nd cycle did not differ from each other and were, respectively, 39 and 57 for cv. Red Yellow Gyro and 61 and 80 for cv. Distans. Regarding the large genotypes, most of these showed seasonality in different periods throughout the year. H. bihai was the only genotype to show production throughout the year and the highest productivity per clump/year, with 33 and 60 stems harvested/clump in the 1st and 2nd cycle, respectively. These results are important to indicate the best species to be cultivated in full sun conditions in the Zona da Mata of the State of Pernambuco, as well as for the selection of superior parents to indicate appropriate crossings.