[5] These diseases are conducive under wet and humid conditions and can cause a yield loss of up to fifty percent if left uncontrolled.
[2] The best method to control ascochyta blights of pea is to reduce the amount of primary inoculum through sanitation, crop-rotation, and altering the sowing date.
[6] Although three different pathogens cause ascochyta diseases of pea, the symptoms are relatively similar to one another, thus making diagnosis difficult.
Ascospores of M. pinodes produce leaf infections that can be identified by many small purple spots on the undersides of leaves.
[2][3] In contrast, the foot rot is usually more severe, oftentimes infecting the stem at the soil line and extending below ground, causing the lateral roots to die.
[7] Ascochyta fungal pathogens are heterothallic, meaning they require two compatible hyphae strains to form their sexual stage.
[citation needed] They release pycnidiospores that come into contact with host tissue and germinate- as the primary inoculum- penetrating through stomatal openings in the Spring.
Next, the fungal hyphae grows and produces pear-shaped pycnidia, eventually releasing pycnidiospores that can reinfect plants or seeds via rain splashes- these are considered the secondary inoculum.
Areas where rainfall and/or high humidity occur during the growing season are most conducive to the success of Ascochyta blight.
Conditions In the 26˚ N - 45˚ N latitudinal range favor this disease due to the moderate temperature, high humidity, and wet plant surface resulting from dew or rain.
[9] The sexual ascospores can be carried long distances by wind, reducing the effectiveness of crop rotation as a defense against Ascochyta blight.
[citation needed] Mycosphaerella blight is the most prevalent Ascochyta disease, which is found in all pea growing regions such as Ireland, United States, Morocco, Iran, Argentina, Australia, and Spain.
[7] The average yield loss in an infected pea crop can range from 10%-50% depending on environmental conditions that may either promote or hinder the disease.