Potential of Some Hybrid Maize Lines to Induce Germination of Sunflower Broomrape

Abstract

Orobanche cumana Wallr. (sunflower broomrape) is a devastating root parasitic weed, causing enormous crop losses throughout the world. Maize (Zea mays L.) is able to induce germination of at least two Orobanche species. Our question was whether or not maize has potential to be used as a “trap crop” for O. cumana. To answer this question, we screened four maize hybrids and their parental lines for their ability to induce O. cumana germination. The results indicated that rhizosphere soil, rhizosphere soil extracts, root extracts, and shoot extracts from three of the four maize hybrids and their parental lines induced significant O. cumana germination. Root extracts generally induced higher germination rates than shoot extracts. Ten‐fold dilutions of the extracts generally induced higher germination rates than either undiluted extracts or 100‐fold dilutions. The ability to induce germination varied significantly among maize hybrid and inbred lines, with the hybrid 3255 × 335 and its parental lines generally inducing the highest O. cumana germination rates. The genetic mechanism for the production of the chemical stimulant that induces O. cumana germination needs to be analyzed further; however, we propose that there is potential for a breeding program to be developed to produce maize lines with greater ability to induce O. cumana germination. These lines could be used as trap crops for the control of this devastating root parasitic weed.