Karyological and Nuclear DNA Variation in Iranian Endemic Muskmelon (Cucumis melo var. inodorus)

Abstract

Muskmelon is one of the important vegetable crops in Cucurbitaceae. Karyotypic analysis and flow cytometric (FCM) measurements of DNA C-values of 20 Iranian endemic muskmelon populations are being reported for the first time. Root tips were examined for karyological studies and fresh young leaves of the muskmelon samples and the standard reference (Parsley, Petroselinum crispum, 2C DNA=4.45 pg) stained with propidium iodide (PI) for FCM measurements. All populations examined were diploids (2n=2x=24), having a mean chromosome length (TL) of 1.36 μm (1.15–1.60 μm), volume (TCV) of 1.03 μm³ (0.73–1.63 μm³) and chromatin length (X) of 32.77 μm (27.56–38.43 μm). FCM measurements showed the mean nuclear DNA content (2C-value) of 0.64 pg (0.53–0.71 pg) and monoploid genome size of 313.4 Mbp (262–350 Mbp). Significant positive linear regression was found between 2C DNA amount and latitude.