The 2012 ASHS Annual Conference

Cut and peel, or Individually Quick Frozen (IQF) baby carrots are the recently introduced high value carrot products of the industry.  Even though there are four baby grades, Fancy is the most preferable grade for IQF baby carrots processing.  A critical issue with cut and peel carrot processing is the incidence of non uniform roots and lower percentage of required baby grades (only 30-33% out of total root weight).  The objective of this experiment was to understand the relationship between soil moisture and seedling emergence to develop a soil moisture based seedling emergence model for cut and peel carrots.  This experiment was conducted under controlled environmental growth chamber conditions with 8 different moisture regimes (–5, –10, –20, –30, –40, –50, –60 and –90 cbars).  Growth chambers were adjusted to provide the following environmental conditions: 21 °C daytime temperature and 15 °C night temperature, with a photoperiod of 16 hr at a light intensity of 180 µ·mol·cm^-2·s^-1.  Sealed, transparent, plastic boxes (30 cm in length) were filled with topsoil.  The variety, Triton, was seeded 2.5 cm deep at the rate of 85 seeds / 30 cm and the experimental design adopted was a Completely Randomized Block Design (RCBD).  Soil moisture potential was continuously monitored using Watermark soil moisture probes installed just below the seeding depth. The number of seedlings emerged per day was monitored until completion of seedling emergence.  Soil moisture potentials of –30 and –40 cbars showed quick and uniform seedling emergence compared to the other treatments. There was no seedling emergence at –90 cbars suggesting that soil moisture potential has a great role to play in delaying or inhibiting carrot seedling emergence, which may be one of the reasons for low Fancy grade recovery.