A new race of sunflower broomrape (<i>Orobanche cumana</i>) with a wider host range due to changes in seed response to strigolactones

Dor, Evgenia; Plakhine, Dina; Joel, Daniel M.; Larose, Hailey; Westwood, James H.; Smirnov, Evgeny; Ziadna, Hammam; Hershenhorn, Joseph

doi:10.1017/wsc.2019.73

Cited by 13 publications

(13 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Strigolactones do not seem to play this role in the sunflower-broomrape interaction, but in other host-parasite systems where STLs do not occur, they could have a similar chemotropic function. In this context, it could be of particular interest to see the chemotropic reaction of a recently detected new race of sunflower broomrape (Dor et al, 2020), which also attacks Solanaceae, for which STLs have not been reported.…”

Section: Discussionmentioning

confidence: 99%

Costunolide Influences Germ Tube Orientation in Sunflower Broomrape – A First Step Toward Understanding Chemotropism

2021

View full text Add to dashboard Cite

Orobanche cumana WALLR. is a host-specific root parasite of cultivated sunflowers with increasing economic importance in Europe, North Africa, and parts of Asia. While sesquiterpene lactones (STLs) released from sunflower roots were identified as natural germination stimulants of O. cumana seeds in the soil, the chemical nature of the signals guiding the emerging germ tube toward the host root has remained unknown hitherto. Thus, we designed a bioassay that allowed the observation of broomrape germination and subsequent germ tube development in the presence of substances with putative chemotropic activity. Root exudates and sunflower oil extracts, both containing STLs in micromolar concentrations, caused the positive chemotropic orientation of germ tubes. A similar positive chemotropic effect was achieved with costunolide, one of the four STLs of sunflower present in the exudate and oil extracts. In contrast, GR24, a synthetic strigolactone (SL) with germination-inducing activity on O. cumana seeds, showed no effect on the germ tube orientation. The effect of costunolide was concentration-dependent and within the range of its natural micromolar occurrence in roots. We assume that an STL gradient is responsible for the stronger inhibition of elongation growth on the host-facing flank of the germ tube compared with the far side flank. This would confer a double role of STLs from sunflower root exudates in the sunflower–broomrape interaction, namely, as germination stimulants and as chemotropic signals.

show abstract

Section: Discussionmentioning

confidence: 99%

Costunolide Influences Germ Tube Orientation in Sunflower Broomrape – A First Step Toward Understanding Chemotropism

2021

View full text Add to dashboard Cite

show abstract

“…In poorly diversified crop consequences (i.e. tobacco monoculture or rapeseed-wheat rotation), this ability can result in the selection of populations that are highly adapted to the crop, as observed on other parasitic plants (Dor et al, 2020).…”

Section: Discussionmentioning

confidence: 99%

Differences in seed germination response of two populations of Phelipanche ramosa (L.) Pomel to a set of GR24 concentrations and durations of stimulation

et al. 2021

View full text Add to dashboard Cite

Phelipanche ramosa is a major weed holoparasite characterized by a broad host range with a suboptimal development on numerous hosts, suggesting inter- or intra-species specificities. Seeds of P. ramosa germinate after exposure to exogenous chemicals exuded by surrounding host roots such as strigolactones, the concentrations of these germination stimulants varying between hosts. In France, P. ramosa is characterized by genetically differentiated populations presenting varying germination rates and a host specificity. The objective of our study was to investigate the sensitivity of seeds of two P. ramosa populations harvested on tobacco and oilseed rape, to a set of GR24 concentrations, a synthetic strigol analogue. The assessment of the germination rate was based on in vitro experiments. Seeds of P. ramosa were placed in Petri dishes with various concentrations of GR24. The cumulative number of germinated seeds of P. ramosa was counted several times after application of the treatment. Cumulative germination curves were analysed using a three-parameter log-logistic model and a time-to-event approach. The results show that the germination rate of P. ramosa seeds depends on the GR24 concentration and the duration of stimulation, but also that the response to these two factors varies greatly according to the origin of the P. ramosa seeds. The difference in germination speed between P. ramosa populations further shows distinct responses at the intraspecific level, thus suggesting that the specialization of P. ramosa probably occurs at least from the first stage of the holoparasite cycle.

show abstract

“…Differences in response to germination stimulant compounds cause host specificity between these species. The emergence of O. cernua is only stimulated by strigolactones (orobanchol, 5-deoxystrigol, 2 0 -epiorobanchol, and GR24), but O. cumana responds to dehydrocostus lactone and GR24 (Dor et al 2020). While O. cernua is a significant component of the Orobanche complex in solanaceous crops (particularly tomato, tobacco, and eggplant) in other countries (Parker 2009), there are no reports of its occurrence in Iran.…”

Section: Orobanche Cumana Wallrmentioning

confidence: 99%

“…Usually, morphological differences are used to identify various broomrape species (Parker and Riches 1993). However, these differences are not clear enough, and the use of molecular markers such as simple sequence repeats (SSR) of nuclear and plastid genomes has been suggested (Dor et al 2020;Westwood et al 2012).…”

Section: Orobanche Cumana Wallrmentioning

confidence: 99%

The problem of Orobanche spp. and Phelipanche spp. and their management in Iran

et al. 2020

View full text Add to dashboard Cite

Broomrape species (Orobanche spp. and Phelipanche spp.) pose a tremendous threat to economically important crops in Iran; however, there is little information on the country’s major broomrape species, their distribution and host range, and the subsequent crop losses they cause. The literature from Iran describes Egyptian broomrape (Orobanche aegyptiaca Pers.), hemp broomrape (Orobanche ramosa L.), Phelipanche nana (Reut.) Beck and Orobanche cumana Wallr. as the major species of broomrape infesting agricultural fields. Solanaceae crops are among the most susceptible crops to infestation by broomrape in the country and farmers are either shifting production to crops with lesser value or abandoning crop production entirely. Among infested crops, tomato (Solanum lycopersicum L.) is the most susceptible and widely infested, resulting in annual crop yield reductions of up to 40%. Chickpea (Cicer arietinum L.) and canola (Brassica napus L.) are also highly susceptible to broomrape infestation. Current control methods (physical, agronomical, biological, and chemical) have not proven to be effective or economic. The microscopic size of broomrape seeds and the presence of a wide range of host plants (weeds and crops) have promoted the spread of broomrape to new areas of Iran. Hence, the familiarization of farmers with the biology of broomrape would be highly effective in finding suitable control measures and in preventing its further distribution.

show abstract

A new race of sunflower broomrape (Orobanche cumana) with a wider host range due to changes in seed response to strigolactones

Cited by 13 publications

References 42 publications

Costunolide Influences Germ Tube Orientation in Sunflower Broomrape – A First Step Toward Understanding Chemotropism

Costunolide Influences Germ Tube Orientation in Sunflower Broomrape – A First Step Toward Understanding Chemotropism

Differences in seed germination response of two populations of Phelipanche ramosa (L.) Pomel to a set of GR24 concentrations and durations of stimulation

The problem of Orobanche spp. and Phelipanche spp. and their management in Iran

Contact Info

Product

Resources

About