Project Overview
Commodities
- Vegetables: broccoli
Practices
- Education and Training: decision support system
Abstract:
Broccoli is a high-value specialty crop that has increased production in recent years within the southeastern U.S. Considered a cold specialty crop, broccoli is very sensitive to the current scenario of climate change. In the southeastern U.S., the weather variability makes broccoli cultivar yield and time to maturity more difficult to predict, creating challenges to crop management practices for broccoli growers and affecting crop yield. The objective of this project was to develop a crop model that simulates broccoli growth and yield for common cultivars grown in the southeastern U.S. and to evaluate the effects of the weather variability of subtropical conditions of the southeastern U.S. on broccoli growth and yield by submitting the proposed crop model to different weather scenarios. Field experiments were conducted during the spring and fall seasons of two consecutive years. Experiments were conducted at the E.V. Smith Research and Extension Center of Auburn University in Shorter, AL, and in collaborator growers. Field trials evaluated the following broccoli cultivars: Emerald Crown, Eastern Crown, Castle Dome, Green Magic, Gipsy, Belstar, and Imperial. Results indicated that daily air temperature (i.e., heat stress) was the main weather parameter affecting broccoli yield. Regardless of cultivar, broccoli grown during the spring growing seasons had lower yields compared to broccoli grown during the fall. This was mostly due to favorable daily air temperature in the fall. However, results indicated that cultivar selection should consider not only yield potential in an individual season but also uniformity of yield across growing seasons, and cultivars Castle Dome, Eastern Crown, and Emerald Crown were consistently among the top-yielding cultivars in both seasons. The developed broccoli crop model had a high accuracy in simulating broccoli total yield (R2=0.85), which had an average prediction yield of 16,000 lb/acre, regardless of the growing season. Ultimately, a cumulative probability analysis of predicted broccoli total yield ranged from 8,000 lb/acre to 18,800 lb/acre, in which broccoli production had a 100% chance of having a yield of 8,000 lb/acre. The cumulative probability of yield had a median probability (50%) of having a yield of 14,000 lb/acre and a low (10%) probability of a yield of 18.800 lb/acre. In conclusion, results from our project confirmed that broccoli grown during the fall season has an increased likelihood of higher yields than broccoli grown in the spring due to favorable daily air temperatures during this period. Consequently, growers must properly determine planting dates and cultivar maturity to achieve potential yields.
Project objectives:
The objective of this project was to develop a crop model that simulates broccoli growth and yield for common cultivars grown in the southeastern U.S. and to evaluate the effects of the weather variability of subtropical conditions of the southeastern U.S. on broccoli growth and yield by submitting the proposed crop model to different weather scenarios.