Differences in Crenate Broomrape Parasitism Dynamics on Three Legume Crops Using a Thermal Time Model

Area of Science:

• Agricultural Science
• Plant Pathology
• Agronomy

Background:

• Root parasitic weeds, like Orobanche crenata (crenate broomrape), significantly limit crop production, especially in legumes within the Mediterranean basin.
• Current control methods, including genetic resistance and chemical treatments, have shown limited success in managing these challenging pests.
• Predictive models for underground parasitic weed evolution are crucial for optimizing management strategies and aiding crop breeding programs.

Purpose of the Study:

• To develop a descriptive model for predicting the developmental stages of Orobanche crenata (crenate broomrape) in legume crops.
• To correlate parasite development with thermal time, specifically growing degree days (GDD).
• To investigate host crop influence on parasite development.

Main Methods:

• A descriptive model was developed based on thermal time.
• Growing degree days (GDD) were correlated with the different developmental stages of Orobanche crenata (crenate broomrape).
• The model was tested across three legume host crops: faba bean, grass pea, and lentil.

Main Results:

• A strong correlation was observed between the developmental stages of Orobanche crenata (crenate broomrape) and growing degree days (GDD).
• Significant differences in parasite development were identified depending on the specific legume host crop.
• The developed model provides a tool for understanding and potentially predicting parasite progression.

Conclusions:

• Growing degree days (GDD) effectively predict Orobanche crenata (crenate broomrape) development in legumes.
• Host crop identity influences the parasitic weed's life cycle, necessitating tailored management approaches.
• This model can support more effective herbicide applications and inform breeding strategies for resistant legume varieties.