Aster Yellows Symptoms on Carrot

Aster Yellows (Mycoplasma): The first symptom of aster yellows is yellowing of the foliage followed by excessive growth and bunching of shoots. Older leaves become twisted and may fall off. Leaves later have a bronzed appearance. Roots are misshapen, and are of poor quality with a proliferation of adventitious roots This organism is transmitted by leafhoppers. Weeds in and surrounding the crop can serve as a reservoir for this pathogen. The disease usually occurs sporadically with little economic loss.

تسببه ميكوبلازما وتظهر الأعراض الأولي في شكل اصفرار للأوراق ثم نمو كثيف للفروع ثم تلتوي الأوراق القديمة  وقد تسقط وتصبح الأوراق برونزية الشكل ويتشوه الجذر. ينتقل المرض بالنطاطات ( القفازات) leafhoppers من الحشائش المجاورة ولكن المرض قلما يحدث أضرار اقتصادية