Avocado App
This app is designed to help avocado growers in Florida, USA to generate irrigation schedule recommendations based on real-time weather and short-term forecasted data to better meet the plant water needs of a given period, conserving water while also minimizing nutrient leaching from the root zone due to excessive irrigation.
Users can register irrigation systems in the app and receive notifications regarding irrigation schedules changes due to differences in the irrigation demand for the next days.
Development
SmartIrrigation Avocado was developed by the University of Florida and operates on iOS and Android platforms. The app determines an evapotranspiration (ET)-based irrigation schedule using crop evapotranspiration (ETc), irrigation systems characteristics, soil characteristics, and root depth. As shown in Equation 1, ETc is calculated from crop coefficients (Kc; Table 1) and reference evapotranspiration (ETo) data, with the ETo data being determined by using the FAO 56 Penman-Monteith method (Allen et al. 1998):
ETc = KcETo (Equation 1)
Weather data from the Florida Automated Weather Network (FAWN) are automatically downloaded from a station in the network close to the field locations or from a station assigned by the user.
The SmartIrrigation Avocado app generates a 15-day irrigation schedule based on the previous five days of ETc calculations. This schedule is updated any time there is a 50% or greater change in the average ETo for the previous five days.
Table 1.Kc values to compute the ETc values
|
Growth Stage |
Description |
Kc |
| Dormancy | Occurs during fall (Nov./Dec.) when temperatures and water demand are generally low. |
0.6 |
| Flower bud development | Generally Dec. through Feb. depending upon cultivar; low demand for water. |
0.8 |
| Flowering and fruit set | Occurs during mid- to late winter. Trees typically drop their leaves during this period, although flowering panicles and set fruit require some water. |
0.7 |
| Fruit growth | Occurs over a 5- to 15-month period depending upon cultivar; high demand for water. |
1.0 |
| After harvest | Demand for water is reduced during this time. |
0.7 |
| Source: Crane (personal communication) | ||