Delineation of the selected Cucumis L. species and accessions using leaf architecture characters

Abstract

Abstract. Masungsong LA, Belarmino MM, Buot IEJr. 2019. Delineation of the selected Cucumis L. species and accessions using leaf architecture characters. Biodiversitas 20: 629-635. Regardless of the several attempts of the early and recent studies to separate the wild species of Cucumis from the cultivated ones, there is still taxonomic confusion brought about by the similarities in morphology of the genus. In a gene bank with so many species and accessions of Cucumis stored, it is appropriate to delineate these numerous accessions to save time and resources as well. This study aims to delineate fifty selected Cucumis accessions based on leaf architecture. Using Unweighted Pair Group Method using Averages (UPGMA) and Euclidean distance coefficient, a cluster analysis for the fifty Cucumis accessions was done. A dendogram with cophenetic coefficient of 0.9606 supported the clustering of the Cucumis species and accessions. At Eucledian distance of 1.5 two major clusters were formed on the basis of secondary vein spacing. Cucumis melo accessions separated from all the remaining accessions of C. myriocarpus, C. metuliferus, C. anguria and C. anguria var longaculeatus for having an increasing towards the base secondary vein spacing while the rest have irregular pattern of secondary vein spacing. Further sub-clustering of the remaining accessions comprising four species were delineated on the basis of tertiary vein (C. myriocarpus), tertiary vein angle to primary (C. metuliferus), and blade class (C. anguria and C. anguria var longaculeatus). Laminar shape delineated C. myriocarpus accessions from each other, apex angle for C. metuliferus accessions, and primary vein size for C. melo accessions. Results implied that leaf architecture is a good tool to classify the numerous accessions of Cucumis.

Short communication: Leaf architecture of 35 species of Dipterocarpaceae cultivated in Forest Area with Special Purposes in Carita, Banten, Indonesia

“…The taxonomist's attention to the leaves' size comparison begins with the theory stating the shapes are not affected by the environment (Balduzzi et al 2017) and the venation is derived genetically (Dickinson et al 1987;Mishra et al 2010). Due to the availability and variations, the leaf is organ-rich information and the source of taxonomy data (Kareem et al 2018;Masungsong et al 2019). Leaf venation is also used to delineate between two confusing Dipterocarpaceae species in the same genera (Mazo and Aribal 2020).…”

Applications of leaf architecture characters in delineating selected species and infraspecific taxa of Genus Cucumis L. (Cucurbitaceae)

“…However, these structures can be challenging to investigate due to their seasonality (da Silva et al 2015). The use of plant vegetative charac-ters such as the leaves are similarly important since they are present throughout the plant's life span Masungsong et al 2019a). Leaf architecture is one of the most valuable tools that is being utilized in many recent taxonomic studies .…”

“…Cucumis sativus and C. melo are just two of the many economically important members of the genus. Several leaf architectural studies on Cucumis have been conducted and contributed to the identification, classification, and delineation of the genus (Rao and Rao 2015;Masungsong et al 2019a;Masungsong et al 2019b;Averion-Masungsong and Buot 2020;Masungsong et al 2022).…”

“…This study assessed the diversity of leaf architectural characters from various accessions of twelve (12) Cucumis taxa, including eight (8) species, three (3) subspecies, and three (3) varieties. It analyzed the leaf architecture of six (6) taxa that were not included in the previous Cucumis leaf architecture studies of Masungsong et al (2019a), Masungsong et al (2019b), Averion- Masungsong and Buot (2020); and Masungsong et al (2022). By combining the current research results with that of previous studies, the accessions were classified and the species, subspecies, and varieties of Cucumis were delineated based on leaf architecture.…”

Leaf architectural analysis of taxonomically ambiguous Hoya lacunosa Blume and Hoya krohniana Kloppenb. & Siar

“…Roth-Nebelsick (2001) has found that in general, the leaf venation pattern of a species is genetically fixed, providing the basis for using the leaf venation as a taxonomic tool. Some applications include Laraño and Buot (2010) on Malvaceae, and Masungsong et al in 2019 on Cucumis species, among others. A comprehensive review of the utility of leaf architecture for resolving plant taxa controversies was published by Buot (2020).…”