Consumers have limited tolerance for defects in the appearance of carrots – consequently growers must strive to employ crop management practices that maximize yields of marketable quality roots. Cultivar selection is a critical factor. Researchers in Nova Scotia showed that commercially available carrot cultivars vary widely in their ability to tolerate drought stress. Drought stress causes forked roots as well as other quality problems. The processing-type cultivars Bergen, Prodigy and Caropak were particularly tolerant of drought stress. Green shoulders (GS) and internal greening (IG) reduce both the visual quality and flavor of carrot. These disorders are caused by the accumulation of chlorophyl which occurs when the carrot crowns are exposed to light. Management practices that reduce exposure of the crowns to light will reduce both the incidence and severity of GS and IG. Select cultivars that produce a good stand with lush top growth. When growing carrots with small tops (ie Nantes-type) seed more densely than normal. Although light hilling once the carrot roots begin to bulk up may reduce the incidence of green shoulders it does not prevent internal greening. This suggests that internal greening occurs relatively early in development of the crop. Splitting is another common quality problem. Incidence of splitting increases as the clay content and nitrogen levels in the soil increase. Warm weather coming into harvest increased cracking whereas irrigation had little impact. Cultivar selection was again important in controlling cracking.
- Lada, Stiles and Pettipas (2004). HortScience 39: 855( Abstr).
- Palanisamy, Lada, Kyei-Boahen, Stiles, Caldwell and Asiedu (2004). HortScience 39: 760 (Abstr).
- Hartz, Johnston and Nunez (2004). HortScience 39: 852 (Abstr)