Evaluation and characterization of physio-morphological and yield performance of native Dendrobium orchid

An experiment was carried out under the shade house of the experimental Farm of Landscape, Ornamental and Floriculture Division at Horticulture Research Centre in Bangladesh Agricultural Research Institute (BARI), Gazipur, during October 2006 to October 2007, for evaluation and characterization of physio-morphological and yield performance of 20 native Dendrobium orchids. Significant variation was observed among the genotypes in respect with all observed parameters except pod size. The tallest plant was found in germplasm D9 (71 cm) while the shortest plant was recorded in D17 (13 cm). 75% germplasm attained plant height within 30 to 50 cm. About one-third germplasm attained plant height below 30 cm. The highest number of pseudobulbs (15.00/plant) were obtained in D6. Only two germplasms, D1 and D14 had hairs in pseudobulb. As regards to the colour of pseudobulb, the observed germplasms showed remarkable variation such as green, yellow, black, white and intermediate colours. On the other hand, 50% elongated cylindrical, 15% oblong, 20% lanceolate, 10% ovate and 5% linear shaped pseudobulb were observed. The leaf characteristics like leaf number, length, breadth, thickness, shape, colour, etc. showed wide range of differences in plant types. As regards to leaf apex, seven genotypes possessed marginate, two genotypes possessed blunt, two genotypes had acuminate and rest of genotypes had acute leaf apex. It revealed that the longest spike (29.0 cm) was produced in D7 while the shortest (2.0 cm) spike was produced by D17. The maximum number of spikes (4.0) and maximum number of flowers per spike (20.0) was observed in the same genotype D11. It had attractive yellowish orange flower colour with sweet fragrance. The maximum flower size (8.0 cm) and durability of flower (31.0 days) was observed in germplasm D1. Its flower was scented and whitish yellow in colour. It was cross compatible to native and exotic cultivars. The germplasm D2, D4, D6, D8, D14, D16, D18 and D19 showed different attractive colour of flowers. They produced medium quality flower considering flowering duration, flower number, flower size, rachis length and spike length. In respect of fragrance of flower, all the native species had fragrance except D18.