Revisiting strategies for reducing the seedbank of Orobanche and Phelipanche spp.

Abstract

Summary Weedy Orobanche and Phelipanche species are important in Southern and Eastern Europe, the Middle East and North Africa, and have recently been reported in the USA, Australia and some countries in South America. Rather than being controlled, the Orobanche and Phelipanche problem is increasing, both in intensity and in acreage. Large areas of new territory are at risk of invasion, if care is not immediately taken to limit the introduction of parasitic seeds and to educate farmers and others to be alert for new infestations. There is an urgent need to re‐evaluate novel integrated Orobanche and Phelipanche management programmes that will allow a better control of the parasite species and limit their distribution. The main obstacle in the long‐term management of Orobanche and Phelipanche infested fields is the durable seedbank, which may remain viable for decades in the field. Large quantities of long‐lived seeds give the parasite genetic adaptability to changes in host resistance and cultural practices. As long as the seedbank is not controlled, the need to control the parasite will persist whenever a susceptible host is grown in the infested field. We discuss strategies for seedbank reduction, paying particular attention to cultural practices, whereas chemical and biological control methods are covered by other reviews in this issue.

Induction of seed germination in Orobanche spp. by extracts of traditional Chinese medicinal herbs

“…Large quantities of long-lived seeds allow the parasite to show a high degree of genetic adaptability to changes in host resistance and cultivation practices. As long as the seed bank is not controlled, the need to control the parasite will persist whenever a susceptible host is grown in an infested field [36].…”

Legume breeding for broomrape resistance

“…A number of strategies of root-parasitic weed control have been developed including cultural practices and biological and chemical control (Joel et al 2007;Rubiales et al 2009b;Fernández-Aparicio et al 2011b). However, only marginal success have been achieved, with most control methods being unfeasible, uneconomical, hard to realize or resulting in incomplete protection.…”

A preliminary approach for modelling the effects of cropping systems on the dynamics of broomrape (Phelipanche ramosa) in interaction with the non-parasitic weed flora

“…At present, there are no commercial herbicides available against P. ramosa and curative measures are limited to manual weeding (Rubiales et al, 2009). The control of the parasite is mostly based on preventive methods such as tillage to limit the contact of host roots and parasite seeds (Rubiales et al, 2009), growing false hosts (which stimulate parasite germination but are immune to fixation) and trap plants (which stimulate germination and are destroyed before parasite seed production) to stimulate fatal parasite germination (Lins et al, 2006), or decreasing the frequency of susceptible crops and varieties in the rotation (Buschmann et al, 2005).…”

“…The control of the parasite is mostly based on preventive methods such as tillage to limit the contact of host roots and parasite seeds (Rubiales et al, 2009), growing false hosts (which stimulate parasite germination but are immune to fixation) and trap plants (which stimulate germination and are destroyed before parasite seed production) to stimulate fatal parasite germination (Lins et al, 2006), or decreasing the frequency of susceptible crops and varieties in the rotation (Buschmann et al, 2005). Consequently, cultivation techniques must be judiciously chosen and combined to Abstract: The current decrease in herbicide use may increase and diversify weed flora in crops as well as companion bioagressors spreading via weeds.…”