Evaluation of Shallow Subsurface Drip Irrigation for the Production of Acorn Squash

Abstract

<jats:p>Subsurface drip irrigation (SDI) has been increasingly used for the production of numerous agronomic crops and a limited number of vegetable crops. To determine the impact of SDI compared with surface drip irrigation (SUR), a study was conducted in 2011 and 2012 with ‘Table Queen’ acorn squash (<jats:italic>Cucurbita pepo</jats:italic> var. <jats:italic>turbinata</jats:italic>) with irrigation initiated at 75% and 50% plant available water (PAW). The study was arranged as a factorial randomized complete block design and plants were grown with two irrigation types (SUR or SDI) and two tensiometer-controlled irrigation regimes. Results from 2011 suggested that SDI used less water compared with SUR at each irrigation set point. However, in 2012, significantly more water was used in all treatments due to warmer temperatures and less rainfall. In 2012, SDI used more water than SUR treatments at the same irrigation set point. In 2012, yield was affected by irrigation treatment. Plants grown using SUR irrigating at 75% PAW had greater numbers of fruit compared with other treatments. Furthermore, the highest yielding treatment had more than twice the number of irrigation events than the other treatments though the average lengths of irrigation events were shorter. Although overall yields were greater in 2012, irrigation water use efficiency (iWUE) was lower than in 2011 due to increased water use. These results suggest that while SDI may have some advantages over traditional SUR, environmental factors during growth can significantly impact the efficiency and productivity of each system.</jats:p>

Comparing a Smartphone Irrigation Scheduling Application with Water Balance and Soil Moisture-based Irrigation Methods: Part I—Plasticulture-grown Tomato

“…Furthermore, placement of sensors within an irrigation zone can be problematic for growers with heterogeneous soils or variable topography within a field. Irrigation thresholds may also be affected by factors such as soil type and depth of drip tubing (Coolong, 2016).…”

“…The SMS-based irrigation regime was automated using paired-switching tensiometers (model RA 6 inches; Irrometer, Riverside, CA) (Coolong, 2016;Coolong et al, 2011). Plots receiving SMS-based irrigation were controlled independently and each plot had a pair of tensiometers.…”

Comparing a Smartphone Irrigation Scheduling Application with Water Balance and Soil Moisture-based Irrigation Methods: Part II—Plasticulture-grown Watermelon

“…The SMS-based irrigation regime was automated using pairedswitching tensiometers (model RA 6 inches; Irrometer, Riverside, CA) (Coolong, 2016;Coolong et al, 2011). In brief, one tensiometer functioned to turn on irrigation at the set point reflecting a higher (drier) soil moisture tension whereas the other turned it off at the set point indicating the lower (wetter) soil moisture tension.…”

“…Soil moisture sensor-based irrigation may use tensiometers, granular matrix, or resistance-based sensors to determine irrigation thresholds (Cardenas-Lailhacar et al, 2010;Munoz-Carpena et al, 2005). Although SMS-based irrigation has been reported to be more efficient than a time or WB-based system (Munoz-Carpena et al, 2005;Zotarelli et al, 2009), sensor readings may be affected by soil type and depth of drip tubing (Coolong, 2016;Dabach et al, 2015). Recently, smartphone applications have been developed that schedule irrigation using real-time weather data to calculate ET o [Smartirrigation App (University of Florida, 2012)].…”

Using Smartphone Technologies to Manage Irrigation

“…Furthermore, placement of sensors within an irrigation zone can be problematic for growers with heterogeneous soils or topography within a field. Irrigation thresholds may also be impacted by factors such as soil type and depth of drip tubing [11].…”