Life history, diversity, and distribution in parasitic flowering plants

Abstract

A review of parasitic plant diversity and outstanding disjunct distributions according to an updated functional classification based on these plants’ life cycles.

The Angiosperm Stem Hemiparasitic Genus Cassytha (Lauraceae) and Its Host Interactions: A Review

“…It has been found that the fruits of C. filiformis floated for months in the Pacific ( Muir, 1933 ). These lead to an additional water-mediated dispersal hypothesis for this species ( Teixeira-Costa and Davis, 2021 ), but further evidence is lacking.…”

“…Parasitic flowering plants either attach to host roots or shoots. They can be chlorophyllous and thus, capable of photosynthesis (hemiparasites) or not (holoparasites) and they can be further divided into four types: root vs. stem hemiparasites, and root vs. stem holoparasites ( Musselman and Press, 1995 ; Teixeira-Costa and Davis, 2021 ). They can also be classified as obligate parasites (which indicates that they need a host plant to acquire nutrients to survive after germination) and facultative parasites (which are capable of reaching maturity without attachment to the host) ( Shen et al, 2006 ).…”

“…They can also be classified as obligate parasites (which indicates that they need a host plant to acquire nutrients to survive after germination) and facultative parasites (which are capable of reaching maturity without attachment to the host) ( Shen et al, 2006 ). According to studies of functional diversity, parasitic flowering plants have been recognized as euphytoid parasites (resembling true plants that are capable of photosynthesis while infesting the underground root system of their hosts), mistletoes (shrubby plants with seeds that germinate autonomously and directly upon the branches of their hosts), parasitic vines (i.e., Cassytha and Cuscuta ), obligate root parasites (parasites that germinate underground, often in response to host-derived chemicals, and infest the root systems of their hosts) and endoparasites (vegetative body of parasitic plants is reduced to mycelial-like strands of cells embedded within their respective host roots or stems) ( Teixeira-Costa and Davis, 2021 ).…”

“…Being stem-parasitic vines, Cassytha and Cuscuta behave similarly and are often referred to together or represented inadvertently as Cuscuta ( Weber, 1981 ; Mishra, 2009 ). However, Cassytha is a hemiparasite whilst Cuscuta is a holoparasite, and they actually differ in many aspects such as the action of the haustorium, their stem appearance, and life span ( Tennakoon et al, 2016 ; Těšitel, 2016 ; Teixeira-Costa and Davis, 2021 ). Study on Cassytha has been relatively neglected, leading to it being less well characterized compared to its companion Cuscuta ( Lanini and Kogan, 2005 ; Mishra, 2009 ).…”

Transcriptional Basis for Haustorium Formation and Host Establishment in Hemiparasitic Psittacanthus schiedeanus Mistletoes

“…Approximately 1.8% of the more than 300,000 known flowering plant species are parasitic, with haustorial parasites (c. 4,800 species) having evolved at least 12 times independently across the angiosperms and showing extremely diverse morphologies, ranging from large trees to tiny herbaceous plants ( Barkman et al, 2007 ; Westwood et al, 2010 ; Twyford, 2018 ; Nickrent, 2020 ). Depending on the site of attachment to the host, parasitic plants are classified into stem (aerial) or root parasites and based on whether these have retained or lost photosynthetic activities as hemiparasites or holoparasites, respectively ( Nickrent and Musselman, 2004 ; Têšitel, 2016 ; Yoshida et al, 2016 ; Teixeira-Costa and Davis, 2021 ). Hemiparasites are photosynthetically active but derive water, minerals, nutrients, and significant amounts of carbon from their hosts, whereas holoparasites lack photosynthetic activity and rely entirely on a host for carbon ( Poulin et al, 2011 ; Twyford, 2018 ; Nickrent, 2020 ; definitions of hemiparasites and other functional classifications reviewed in Têšitel, 2016 ; Teixeira-Costa and Davis, 2021 ).…”