Feasibility of using pulse drip irrigation for increasing growth, yield, and water productivity of red raspberry

Authors: CARROLL, JESSE - Missouri State University; Orr, Scott; BENEDICT, CHRIS - Washington State University; DEVETTER, LISA - Washington State University; Bryla, David

Submitted to: HortScience
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/18/2023
Publication Date: 2/8/2024
Citation: Carroll, J.L., Orr, S.T., Benedict, C.A., DeVetter, L.W., Bryla, D.R. 2024. Feasibility of using pulse drip irrigation for increasing growth, yield, and water productivity of red raspberry. HortScience. 59(3):332-339. https://doi.org/10.21273/HORTSCI17467-23.
DOI: https://doi.org/10.21273/HORTSCI17467-23

Interpretive Summary: Pulse irrigation is the practice of applying water in a series of small intervals each day, until the total amount of water required by the crop is added. When managed properly, pulsing can reduce deep percolation and runoff, and supply water and nutrients at an optimum rate for plant uptake, increasing growth and production relative to applying the same amount of water in a single continuous application. While pulse irrigation has been studied extensively over the years - often with mixed results - it has not been tested in most berry crops. Therefore, in cooperation with a student at Oregon State University and researchers at Washington State University, ARS scientists in Corvallis, OR tested the feasibility of using pulse drip irrigation in red raspberry. By the second and third year of application, pulsing increased yield by an average 1100 lbs/acre, which was due primarily to more and larger canes on the plants. Based on recent market prices for processed raspberries, this increase in fruit production was equivalent to $980-1,000 per acre each year. As a result of this research, growers in Washington State are beginning to adopt the use of pulse drip irrigation in their raspberry fields.

Technical Abstract: Pulse irrigation is the practice of applying water in a series of small intervals each day, until the total amount of water required by the crop is added. When managed properly, pulsing can reduce deep percolation and runoff, and supply water and nutrients at an optimum rate for plant uptake, increasing growth and production relative to applying the same amount of water in a single continuous application. The objective of the present study was to determine whether pulse irrigation was beneficial in red raspberry (Rubus idaeus L.). The study was conducted in a mature field of ‘Wakefield’ raspberry located at a commercial farm in Lynden, WA. Soil at the site was a silt loam. Treatments were applied for three growing seasons (2018-2020) and included continuous or pulse irrigation using a single lateral of drip tubing per row. Continuous irrigation was applied up to 4 h per day, as needed, while pulse irrigation was programmed to operate for 30 min every 2 h, up to eight times per day, using approximately the same amount of water as the continuous treatment. Fruit were machine-harvested every few days over a period of 6 weeks (July-August) each growing season. Pulsed water applications increased soil water availability relative to continuous irrigation and, during the second and third year of the study, increased total fruit production by 1210-1230 kg/ha. Based on recent market prices for processed raspberries, this increase in fruit production was equivalent to $2420-2460/ha per year. Much of this increase occurred during the latter 3-4 weeks of the harvest season and was primarily due to larger fruit size with pulse drip during the second year and more berries per plant during the third year. Pulse drip irrigation also increased the diameter of floricanes and primocanes by 8% to 11% during the third growing season and, by the end of the second and third year, increased total canopy cover by 6.5% and 5.2%, respectively. There were also negative effects of pulsing the water applications, including lower sugar to acid ratio in the berries during the second year and less K and B in the soil during the third year; however, these effects were minor and either opposite than or unaffected by pulsing during other years. Based on these results, pulse drip irrigation appears to be a promising method for improving fruit production and water productivity of red raspberry.