There has been recent attention on the limited supplies of lettuce and leafy greens. The supply issue has been largely attributed to crop damage associated with an aggressive pest and disease complex of INSV and soil-borne diseases.
What is INSV or thrips-vectored Impatiens Necrotic Spot Virus? Lettuce fields are infected by INSV via thrips migrating from infected host plants. Plants infected by INSV can have dark spotting and yellowing, which resembles the effects of sunburn on the leaves. Another plant disease, Pythium wilt (PW), often accompanies INSV infections and causes the plant to wilt or collapse making this truly a complicated pest/disease issue for farmers.
In 2022, disease pressure was exacerbated by unseasonably warm weather stretches which caused prolonged stress on the plant making the lettuce more susceptible to disease impacts.
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