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Combretum indicum (L.) DeFilipps seeds have anthelmintic properties and are recognized to be medicinal; however, the array of their morphological characters, behavior in storage, and germination pattern are not yet established. This is the first detailed report elucidating the seed characteristics of C. indicum which may influence postharvest handling, longevity in storage, and conservation strategy among others. Seeds of 10 C. indicum accessions from the Philippine Biorepository Network were morphologically characterized in situ and ex situ. Previously stored seeds were subjected to desiccation and cold treatments to identify behavior in storage. Germination tests were conducted to identify the viability of the seeds in the various treatments, and seedling development was recorded and framed according to the extended Biologische Bundesanstalt, Bundessortenamt und CHemische Industrie (BBCH) scale. C. indicum seed shape ranged from elliptic to ovate with stellate, five-winged, angular cross-section. It has 16.30 ± 3.06 mm length and 6.62 ± 0.75 mm diameter. Its morphological characters were found to characteristically vary between accessions indicating infraspecific diversity. Its seeds are orthodox as they could tolerate drying to about 1.65% moisture content and subsequent storage in − 18 °C for 60 days. Days to seed germination ranged from 5 to 44 days after sowing. It has a hemi-cryptocotylar hypogeal germination pattern which starts with the characteristic emergence of the radicle at the stylar-end (BBCH 05) and distinctly culminates in the unfolding of a pair of leaves arranged in an opposite to sub-opposite manner (BBCH 11).

Background: Seed characteristics of Tabernaemontana pandacaqui Lam., an indigenous medicinal plant species from the Philippines, were investigated to help identify appropriate conservation strategies. Methods: Mature seeds were tested for viability at different dormancy-breaking treatments and storage conditions. Seeds were also characterized morphologically and the seedling developmental pattern was established using the Biologische Bundesanstalt, Bundessortenamt and CHemische Industrie (BBCH) scale. We also determined the preliminary chemical composition through qualitative phytochemical screening and proximate analysis. Result: Seeds of T. pandacaqui are obovate in shape with a 1000-seed weight of 20.99±0.62 g at 4.7% moisture content. Removal of the aril from the fresh seeds improved germination from 30%±0.98 to 84%±0.71 and shortened the time to seedling emergence from 45 days to 4 days after sowing. The seeds can tolerate drying to 4.7% moisture content and storage at -10°C for 3 months; thus, they have orthodox storage behavior. The germination pattern is epigeal phanerocotylar type, wherein the foliaceous cotyledons are raised (BBCH 09) and unfolded above the soil surface (BBCH 10). The seedling then develops an ovate to elliptic-shaped first true pair of leaves (BBCH 12) completing the germination process. The pre-dried seeds also have a high oil content of 28.7407±0.09316% with a strong presence of alkaloids and saponins. This indicates that the seed is amenable to ex-situ conservation through seedbanking, but its viability must be monitored in shorter intervals due to its high oil content.

In the Philippines, Combretum indicum (L.) DeFilipps is a native crop important for medicinal and ornamental purposes. Despite its importance in the country, there had been no attempts to elucidate its intraspecific variation. In-situ and ex-situ characterization were done in 15 C. indicum accessions from the collection of the Philippine Biorepository Network (for medicinal plants). The accessions were then planted in the field at three replicates and grown for 12 months at the Institute of Crop Science (ICropS), University of the Philippines Los Banos. Eleven quantitative characters were measured, and 24 qualitative characters were observed. Four distinct floral morphotypes potentially correlated to the ability to bear seeds in situ and ex situ have been identified. The first morphotype can be delineated in terms of the pin type stigmatic position respective to the anther, explicative petal ptyxis, and abaxial petal color. The second morphotype bears the longest flowers and largest petals with a level stigmatic position, while the third morphotype bears the shortest villous thrum-type flowers. The fourth morphotype is the only morphotype capable of producing staminoid petals. Out of the four floral morphotypes, only the first morphotype was observed to have high fecundity in situ and ex situ which indicates potential higher utility as a medicinal plant in the Philippines. This is the first detailed report on the intraspecific variation of C. indicum.

A systematic method for determining colour descriptor states using image analysis is proposed using pili (Canarium ovatum) as a model. Kernel images of 52 pili accessions from the core collection of the Institute of Crop Science and National Plant Genetic Resources Laboratory, University of the Philippines Los Baños were captured using a calibrated VideometerLab 3 setup. Colour descriptor states were derived from the average International Commission on Illumination lightness (L*), green–red (a*) and blue–yellow (b*) colour component values. Cluster analysis and subsequent colour-parameter averaging per cluster were performed to produce representative colour values of descriptor states. The Euclidian distance (Delta E) of 3.5 was used to cut the cluster into readily distinguishable colour differences resulting to three descriptor states – light brown, brown and dark brown. Continuous colour variation of brown colour was observed indicating a possible quantitative nature of the trait. The use of delta E in elucidating the descriptor lists served as a gauge in successfully identifying distinguishable variations between colours. The method described can be applied to the elucidation of colour descriptor states of all parts of the plant of all crop species.