Ploidy levels in Citrus clementine affects leaf morphology, stomatal density and water content

Abstract

The objective of the present study was to understand the relationship among leaf morphology, stomatal characteristics and water relations in triploids generated through anther culture and their counterpart diploid plant of C. clementina. Triploid plants possessed small and narrow leaves as compared to diploid plant as evident by less leaf length, leaf width and leaf area. By contrast, the leaf index was observed to be more in triploids than haploid ones. Flow cytometric analysis re-confirmed the ploidy levels of heterozygous plant Hd as diploid and the ploidy of Th1, Th2, Th3 and Th4 plants as triploids. A positive relation was found between ploidy level and stomatal guard cell length and width, whereas a negative relation was observed between the stomata density and ploidy level. The stomatal density was reported to be 6.2±0.2 stomata per µm² in diploid plant, while stomatal density varied between 3.0 and 3.6 stomata per µm² in triploids. Leaf relative water content (RWC) was slightly higher in triploids (90.8 to 93.1%) than diploid (89.5%). The leaf water loss was found to be marginally higher in diploid than in triploid plants. Our results show that increase in ploidy level from diploids to triploids caused an effect on leaf morphology and stomatal characteristics with probable consequences to water relations of leaves. This research will serve as an important basis for future work on complete analysis of both morphological and behavioural traits of the leaf stomata and transpiration rates in relation to diploid versus triploid plants.

anther culture; citrus; diploid; relative water content; stomata; triploid; water loss

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Publication Dates

• Publication in this collection
  10 Feb 2014
• Date of issue
  Dec 2013

History

• Received
  13 Aug 2013
• Accepted
  05 Dec 2013