The cinnamon flowers exhibit protogynous dichogamy with 2 flower types “Type A” and “Type B” which first flowers during morning and evening respectively. This floral cycle causes a temporal barrier to the maintenance of elite breeding material and for hybridization with desired parents. Determination of variation in flower and inflorescence morphology can shed light on functional diversity in “Type A” and “Type B” flowers. In order to study these variations, a survey of cultivated cinnamon lands and wild habitats was conducted in fifteen locations in the Matara district. Peduncle length (PDL), flower length (FL), flower width (FW), and floral tube length (FTL) varied among cinnamon accessions collected. The variation in tepal shape was distinct: the two whorls of tepals of a single flower exhibited two shapes. The current investigation of differences in inflorescence, floral morphology and floral abnormalities of Cinnamomum verum provides information about their diversity, and recommends molecular analysis to further determine the genetic basis of two flower types in progynous dichogamy.

Cinnamomum verum is the most important spice produced by Sri Lanka. This study was carried out to fill the gap of knowledge on diversity of Sri Lankan cinnamon through morphological characterization. Therefore, an eco-geographic survey in major growing areas followed by the development of a core collection and vegetative propagation of the total collection for ex-situ conservation were carried out. Two hundred and sixty nine cinnamon accessions were collected. The average shoot regeneration frequency of 269 accessions was 47.76% after one month of vegetative propagation. The collection was established at Faculty of Agriculture, University of Ruhuna for further studies. The collection was characterized for 15 quantitative and qualitative characters of leaf, stem and inflorescence among which, a wide variation was detected for leaf characters mainly. Leaf length positively correlated with Leaf width (+0.643) and Petiole length (+0.483). Principal component analysis (PCA) revealed that there were 3 dimensions of PCA explaining 88.85% of total variance. In Hierarchical cluster analysis based on above characters, 269 accessions were grouped into five clusters at rescaled distance of 0.1. A representation of 10% accessions was randomly selected from each cluster to develop a core collection with 33 accessions. The core collection of 33 accessions was clustered into five groups according to the same method at rescaled distance of 0.075. The core collection is a representation of the total collection as clusters of the two dendograms could be overlapped. Morphological characterization and core collection development during this study will be useful for germplasm management, conservation and varietal improvement through breeding programmes.

Unavailability of information on photoperiod sensitivity of traditional rice is a disadvantage in breeding rice for adaptation to changing climatic conditions and for optimum plant architecture. This experiment was conducted to address the above problem through determination of variation in days to flowering (DF) and morphological traits of twenty eight selected very early maturing Sri Lankan traditional rice accessions under three photoperiod conditions: short day (SD), day neutral (DN) and long day (LD). Although rice is considered to be a facultative short day plant, 12 accessions (2088, 2979, 4615, 3970, 4245, 2091, 3450, 3883, 4217, 6741, 3738 and 3677) flowered significantly late under SD over LD, while accession 4223 flowered significantly late under DN. Fifteen accessions (3943, 4042, 4734, 3693, 4513, 3845, 4390, 4144, 4220, 4223, 4237, 4387, Bg 300, At 308 and Bg 379-2) flowered significantly early under SD over LD. Four accessions (3457, 3884, 6305 and 4358) were non-responsive to photoperiod for flowering time. Plant height significantly increased only in accession 4217 under SD. Higher plant height under DN was obtained from At 308 and accession 3883. Photoperiod did not affect plant height in accession 4237 and Bg 379-2. LD only or both LD and DN conditions produced significantly higher plant height irrespective of photoperiod responsiveness for DF in rest 26 accessions. Variation in response to photoperiod for DF and plant architecture in very early maturing Sri Lankan rice indicates the potential diversity of genetic factors for photoperiod response for future use in rice breeding.