Ecophysiology of the holoparasitic angiosperm Cistanche phelypaea (Orobancaceae) in a coastal salt marsh

Abstract

Cistanche phelypaea (L.) Cout. (Orobancaceae) was found parasitising the roots of the succulent shrublets Arthrocnemum macrostachyum (Moric.) K.Koch (Chenopodiaceae) in a coastal salt marsh in Qatar. Measurements were conducted to identify soil properties, host, and noninfected plants by soil excavations to expose the haustoria of the parasite attached to the host roots. The water potential, osmotic potential, pressure potential, and chemical analyses were determined in parasite, host, and noninfected plants. Crown diameter and dry mass of the host plants were smaller than in the noninfected plants. A gradient of water potential existed between the host root and the underground tuberous body of the parasite. Potassium was the major cation found in the parasite, while sodium was dominant in the host and noninfected plants. The nitrogen, soluble sugars, total amino acids, and starch contents of the parasite were higher than those of the host and noninfected plants. The high ratio of K + to Ca 2+ in the parasite indicates that it is phloem-feeding. The high nutrient element contents and metabolic products in the parasite are possibly related to the creation of osmotic and water potential gradients between the host and C. phelypaea.

Assessment of coastal salt marsh plants on the Arabian Gulf region

“…Additionally, various chemical analyses were measured e.g., in Kuwait, isotopic signature δ 13C of salt marsh producers and consumers ( Al-Zaidan et al, 2006 ), chemical analysis of sediment ( Gunatilaka, 1990 , Al-Dousari et al, 2008 ). Whereas chemical reports on Qatar were about both salt marsh plants and sediment ( Yasseen and Al-Thani, 2007 , Yasseen and Abu-Al-Basal, 2008 , Yasseen and Abu-Al-Basal, 2010 , Fahmy, 2013 ). Yet, chemical analysis studies in Iran mainly were about plants ( Zakery-Asl et al, 2014 , Motamed et al, 2016 ), except for one study on the elemental composition of 108 plants and soil ( Matinzadeh et al, 2019 ).…”

Diversity and potential plant growth promoting capacity of seed endophytic bacteria of the holoparasite Cistanche phelypaea (Orobanchaceae)

“…C. phelypaea is parasitizing on roots of halophytic plants 6 . Thus, the holoparasite should possess defense mechanisms against the abiotic conditions in the saline soil, the high osmotic pressure of the soil solution, and must be able to cope with the salt tolerant nature of the host plant as well 17 . The parasitic plants are affected by salinity stress both directly and undirectedly.…”

“…There exist a limited number of studies on the biology and ecology of C. phelypaea . Most works concern the distribution, biomass, host range, the allelopathic potential, and the ecophysiological interactions between C. phelypaea and its host 6 , 7 , 17 , 56 – 58 .…”

Taxonomic traits in the microstructure of flowers of parasitic Orobanche picridis with particular emphasis on secretory structures

“…The flowers attract insects with their fragrance (Hegnauer 1990;Piwowarczyk et al 2015;Tóth et al 2016) and offer pollen and nectar reward (Saghir and Dastgheib 1978;Ollerton et al 2007). Annular nectaries in Orobanche flowers are located at the base of the ovary (Kreutz 1995;Bekker and Kwak 2005;Fahmy 2013). The nectar of the parasite usually exhibits a lower concentration than that in the host plant (Ollerton et al 2007).…”