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

Abstract

<jats:p>A new smartphone vegetable irrigation scheduling application (VegApp) was compared with current irrigation scheduling recommendations and soil moisture sensor (SMS)–based irrigation for growing tomato (<jats:italic>Solanum lycopersicum</jats:italic>) in southern Georgia during Spring 2016 and 2017. Plants were grown using plastic mulch and drip irrigation following standard production. The VegApp-scheduled irrigation based on crop evapotranspiration (ET<jats:sub>c</jats:sub>) values calculated daily from meteorological data retrieved from nearby weather stations, whereas ET<jats:sub>c</jats:sub> rates for current water balance (WB)–based recommendations were calculated from historic averages for the region. Water usage, soil moisture tension, fruit yield and quality, and foliar macronutrient content were measured. In 2016, plants grown using SMS-based irrigation applied the least water followed by the VegApp- and WB-grown plants. In 2017, WB-treated plants received the least water, followed by VegApp- and SMS-grown plants. Total marketable yields were similar among treatments and years. Irrigation water use efficiency (IWUE) varied between year and irrigation regime, with SMS-grown plants having a significantly greater IWUE than the other treatments in 2016. Plants irrigated using the VegApp had a greater IWUE than SMS-irrigated plants in 2017. Differences in IWUE were largely the result of variable irrigation volumes and not changes in yield. Fruit total soluble solids (TSS) were unaffected by treatment in either study year. Fruit pH was affected by irrigation treatment in 2017. Foliar nitrogen concentrations were affected by irrigation regime in 2017, with VegApp-grown plants having significantly greater concentrations of foliar N than other irrigation treatments. The results of this study suggest that the VegApp could be a reliable tool that can be used by growers to produce yields comparable to currently accepted irrigation scheduling practices and reduce water use in some seasons.</jats:p>

Increasing Air Temperatures and Its Effects on Growth and Productivity of Tomato in South Florida

“…L.), turf grass, strawberry ( Fragaria spp. ), avocado ( Persea americana ) [ 34 ], tomato ( Solanum lycopersicum L.) [ 32 , 35 , 36 ] and watermelon ( Citrilus lanatus (Thumb.) Matsun.…”

“…and Nakai) [37]. The SI scheduling method has not only been reported to significantly increase water savings but also increase crop yield [32,37] and improve iWUE [35,38] as well as increase in crop nutrient recovery by maintaining nutrient within the root zone [35]. More detailed information on SI technology is available at https://smartirrigationapps.org/.…”

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

“…Irrigation volumes applied using the VegApp were more similar to ET c of watermelon than tomato [Solanum lycopersicum (Miller et al, 2018)]. This suggests that the K c and DAT model used in the VegApp may be more appropriate for drip-irrigated plasticulture-grown watermelon than tomato in southern Georgia.…”

Advances in Hass avocado irrigation scheduling under digital agriculture approach

“…Recently, other IS apps have been developed for tomato (Miller et al, 2018) and grains crops (Freebairn et al, 2018), exploiting artificial intelligence techniques (Ferreira et al, 2020), reading soil matric potential devices (UNL, 2019), and integrating IS data to IoT environments (Sales et al, 2020). After validating in field conditions, authors of the three first apps mentioned above concluded IS apps do reliably estimate the soil water dynamic and positively impact WUE.…”