Comparative developmental anatomy of the taproot of the cucurbitaceous vines Citrullus colocynthis (perennial), Citrullus lanatus (annual) and Cucumis myriocarpus (annual)
Geoffrey E. Burrows A B and Razia S. Shaik AA Graham Centre for Agricultural Innovation (NSW Department of Primary Industries and Charles Sturt University), School of Agricultural and Wine Sciences, Charles Sturt University, Locked Bag 588, Wagga Wagga, NSW 2678, Australia.
B Corresponding author. Email: gburrows@csu.edu.au
Australian Journal of Botany 62(7) 537-545 https://doi.org/10.1071/BT14124
Submitted: 2 June 2014 Accepted: 16 October 2014 Published: 19 February 2015
Abstract
The genus Citrullus (Cucurbitaceae) consists of four species of desert vines. Two species (Citrullus colocynthis and Citrullus lanatus) are widespread weeds on several continents. Above ground, they can be relatively difficult to distinguish apart. However, Citrullus colocynthis is a perennial with a tuberous taproot, whereas Citrullus lanatus is an annual with a slender taproot. We studied the morphology and anatomy of taproot development to better understand their structural and ecological differences. The annual Citrullus lanatus reached close to its maximum taproot diameter (~3 mm) soon after germination. The vascular cambium formed four relatively broad triangular sectors of fibres in which were embedded relatively large diameter vessels. These sectors were separated by narrower triangular areas of secondary ray parenchyma. In contrast, the taproot diameter of the perennial Citrullus colocynthis continued to increase during the study, reaching ~20 mm after 14 weeks. Most of this substantial root consisted of secondary xylem parenchyma, with a low density of relatively small diameter vessels and few fibres. The remarkable differences in root morphology and anatomy of the studied species of Citrullus are related to differences in their annual and perennial lifecycles. Interestingly, the slender taproots of Citrullus lanatus were calculated to have a similar theoretical hydraulic conductance to that of Citrullus colocynthis (large diameter taproot).
Additional keywords: camel melon, colocynth, cucurbit, Cucurbitaceae, morphology, periderm, phellem, paddy melon, root anatomy, tuberous root, vessel.
References
Ajuru MG, Okoli BE (2013) Comparative vegetative anatomy of some species of the family Cucurbitaceae Juss in Nigeria. Research Journal of Botany 8, 15–23.| Comparative vegetative anatomy of some species of the family Cucurbitaceae Juss in Nigeria.Crossref | GoogleScholarGoogle Scholar |
Al-Zahrani HS, Al-Am KH (2006) A comparative study on Citrullus colocynthis plants grown in different altitudinal locations in Saudia Arabia. American–Eurasian Journal of Scientific Research 1, 1–7.
Althawadi AM, Grace J (1986) Water use by the desert cucurbit Citrullus colocynthis (L.) Schrad. Oecologia 70, 475–480.
| Water use by the desert cucurbit Citrullus colocynthis (L.) Schrad.Crossref | GoogleScholarGoogle Scholar |
Carlquist S (1992) Wood anatomy of selected Cucurbitaceae and its relationship to habit and systematics. Nordic Journal of Botany 12, 347–355.
| Wood anatomy of selected Cucurbitaceae and its relationship to habit and systematics.Crossref | GoogleScholarGoogle Scholar |
Dane F, Lang P, Bakhtiyarova R (2004) Comparative analysis of chloroplast DNA variability in wild and cultivated Citrullus species. Theoretical and Applied Genetics 108, 958–966.
| Comparative analysis of chloroplast DNA variability in wild and cultivated Citrullus species.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXktlalsbw%3D&md5=07826f91916c88bb4921197857853f16CAS | 14634729PubMed |
Dane F, Liu J, Zhang C (2007) Phylogeography of the bitter apple, Citrullus colocynthis. Genetic Resources and Crop Evolution 54, 327–336.
| Phylogeography of the bitter apple, Citrullus colocynthis.Crossref | GoogleScholarGoogle Scholar |
Dittmer HJ, Roser ML (1963) The periderm of certain members of the Cucurbitaceae. The Southwestern Naturalist 8, 1–9.
| The periderm of certain members of the Cucurbitaceae.Crossref | GoogleScholarGoogle Scholar |
Dittmer HJ, Talley BP (1964) Gross morphology of tap roots of desert cucurbits. Botanical Gazette 125, 121–126.
| Gross morphology of tap roots of desert cucurbits.Crossref | GoogleScholarGoogle Scholar |
Ewers FW, Carlton MR, Fisher JB, Kolb KJ, Tyree MT (1997) Vessel diameters in roots versus stems of tropical lianas and other growth forms. International Association of Wood Anatomists Journal 18, 261–279.
Getahun A (1971) Developmental anatomy of tubers of anchoté: a potential dryland tuber crop. Acta Horticulturae 33, 51–64.
Getahun A (1974) Developmental anatomy of seedlings of anchoté, Coccinia abyssinica (W. & A.) Cogn. (Curbitaceae). Botaniska Notiser 127, 211–223.
Harden GJ (1990) Cucurbitaceae. In ‘Flora of New South Wales. Vol. 1’. (Ed. GJ Harden) pp. 441–448. (New South Wales University Press: Sydney)
Hargreaves BJ (1996) Tubers and bulbs as an adaptive strategy in the Kalahari. In ‘The biodiversity of African plants’. (Eds LJG van der Maesen, XM van der Burgt, JM van Medenbach de Rooy) pp. 88–91. (Kluwer Acacemic Publishers: Netherlands)
Hearn DJ, Poulsen T, Spicer R (2013) The evolution of growth forms with expanded root and shoot parenchymatous storage is correlated across the eudicots. International Journal of Plant Sciences 174, 1049–1061.
| The evolution of growth forms with expanded root and shoot parenchymatous storage is correlated across the eudicots.Crossref | GoogleScholarGoogle Scholar |
Heywood VH, Brummitt RK, Culham A, Seberg O (2007) ‘Flowering plant families of the world.’ (The Royal Botanic Gardens, Kew: London)
Jeffrey C (1980) A review of the Cucurbitaceae. Botanical Journal of the Linnean Society 81, 233–247.
| A review of the Cucurbitaceae.Crossref | GoogleScholarGoogle Scholar |
John KJ, Antony VT, Marydas J, Karuppaiyan R (2009) Tuber morphology, germination behaviour and propagation efficiency in three edible Momordica (Cucurbitaceae) species of India. Genetic Resources and Crop Evolution 56, 861–868.
| Tuber morphology, germination behaviour and propagation efficiency in three edible Momordica (Cucurbitaceae) species of India.Crossref | GoogleScholarGoogle Scholar |
Kartusch B, Kartusch R (2008) Stem anatomy of Acanthosicyos horridus (Cucurbitaceae). South African Journal of Botany 74, 647–650.
| Stem anatomy of Acanthosicyos horridus (Cucurbitaceae).Crossref | GoogleScholarGoogle Scholar |
Klimešová B, Klimeš L (2007) Bud banks and their role in vegetative regeneration – a literature review and proposal for simple classification and assessment. Perspectives in Plant Ecology, Evolution and Systematics 8, 115–129.
| Bud banks and their role in vegetative regeneration – a literature review and proposal for simple classification and assessment.Crossref | GoogleScholarGoogle Scholar |
Kumar P, Rao GD, Bilakanti L, Setty SR (2010) Pharmacognostical studies on tubers of Momordica tuberosa Cogn., Cucurbitaceae. Revista Brasileira De Farmacognosia – Brazilian Journal of Pharmacognosy 20, 7–11.
| Pharmacognostical studies on tubers of Momordica tuberosa Cogn., Cucurbitaceae.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXntFyjsb4%3D&md5=84b1b8cfe2e1e064a8316a2d4e05b5daCAS |
Nimmakayala P, Islam-Faridi N, Tomason YR, Lutz F, Levi A, Reddy UK (2011) Citrullus. In ‘Wild crop relatives: genomic and breeding resources. Vegetables’. (Ed. C Kole) pp. 59–66. (Springer-Verlag: Berlin)
Olson ME (2003) Stem and leaf anatomy of the arborescent Cucurbitaceae Dendrosicyos socotrana with comments on the evolution of pachycauls from lianas. Plant Systematics and Evolution 239, 199–214.
| Stem and leaf anatomy of the arborescent Cucurbitaceae Dendrosicyos socotrana with comments on the evolution of pachycauls from lianas.Crossref | GoogleScholarGoogle Scholar |
Schaefer H, Renner SS (2011) Cucurbitaceae. In ‘The families and genera of vascular plants. Vol. X. Flowering plants. Eudicots: Sapindales, Cucurbitales, Myrtaceae’. (Ed. K Kubitzki) pp. 112–174. (Springer-Verlag: Berlin)
Schaefer H, Heibl C, Renner SS (2009) Gourds afloat: a dated phylogeny reveals an Asian origin of the gourd family (Cucurbitaceae) and numerous oversea dispersal events. Proceedings. Biological Sciences 276, 843–851.
| Gourds afloat: a dated phylogeny reveals an Asian origin of the gourd family (Cucurbitaceae) and numerous oversea dispersal events.Crossref | GoogleScholarGoogle Scholar |
Schweingruber FH, Börner A, Schulze E-D (2011) ‘Atlas of stem anatomy in herbs, shrubs and trees. Vol. 1.’ (Springer-Verlag: Berlin)
Scott FM (1943) Survey of anatomy, ergastic substances, and nuclear size in Echinocystis macrocarpa and Cucurbita pepo. Botanical Gazette 104, 394–408.
| Survey of anatomy, ergastic substances, and nuclear size in Echinocystis macrocarpa and Cucurbita pepo.Crossref | GoogleScholarGoogle Scholar |
Sen DN, Bhandari MC (1974) On the ecology of a perennial cucurbit in Indian arid zone – Citrullus colocynthis (Linn.) Schrad. International Journal of Biometeorology 18, 113–120.
| On the ecology of a perennial cucurbit in Indian arid zone – Citrullus colocynthis (Linn.) Schrad.Crossref | GoogleScholarGoogle Scholar |
Shaik RS, Gopurenko D, Burrows GE, Urwin NAR, Lepschi BJ, Hildebrand SM, Weston LA (2012) Identification of the invasive weeds, camel melon, prickly paddy melon and colocynth in Australia – a morphological and molecular approach. In ‘18th Australasian weeds conference’, 2012, Melbourne, Vic., Australia, pp. 73–77.
Sharma NK, Thanki YJ, Bhardwaj S (2011) Anatomical studies of Lagenaria siceraria (Mol.) Standl and Cucumis sativa L. (Cucurbits.). Asian Journal of Plant Science 10, 158–161.
| Anatomical studies of Lagenaria siceraria (Mol.) Standl and Cucumis sativa L. (Cucurbits.).Crossref | GoogleScholarGoogle Scholar |
Zohary M (1961) On hydro-ecological relations of the near east desert vegetation. In ‘Arid zone research. Vol. 16. Plant–water relationships in arid and semi-arid conditions’. pp. 199–212. (UNESCO: Paris)
