between housing developments and production fields using deep fresh water wells. High-impact sprinkler irrigation (4 to 5 gal/min per head) is used during strawberry production for two primary reasons: transplant establishment and freeze protection. For
Bielinski M. Santos, Teresa P. Salame-Donoso, and Alicia J. Whidden
Jeff B. Million and Thomas H. Yeager
Burger, 1997 ), comparatively little research has evaluated the ability of containerized plants to capture sprinkler irrigation water. Irrigation capture is important because containers occupy only a fraction of the production area even when closely
C.A. Sanchez, R.L. Roth, and B.R. Gardner
Six field studies were conducted from 1980-88 to evaluate the response of cabbage (Brassica oleracea L., Capitata group) to sprinkler irrigation and sprinkler-applied N fertilizer on a coarse-textured soil. The plots were irrigated using a modified self-moving lateral sprinkler irrigation system that applied five levels of water and five levels of N (liquid NH4NO3) in specified combinations of central composite rotatable design. Cabbage yields were significantly increased by water and N applications in all experiments. The N rates predicted for maximum yield exceeded typical cabbage N fertilizer recommendations. However, the above-average plant populations used in these studies resulted in above-average yields and plant N accumulation. Deficit and excess irrigation produced negative results. Generally, cabbage production was optimized and N losses to the environment were minimized when crops were irrigated for evapotranspiration (ET) replacement. However, even when irrigated for ET replacement, these data demonstrate the potential for N leaching at high N rates, presumably as a result of rainfall.
I. Iglesias, J. Graell, G. Echeverría, and M. Vendrell
The influence of supplemental sprinkler irrigation on fruit color of `Oregon Spur Delicious' (Trumdor) apples (Malu×domestica Borkh.) was evaluated in the area of Lleida (NE Spain) over a 3-year period. Cooling irrigation was applied for 2 hours daily for 25-30 days preceding the harvest. Three treatments were evaluated: 1) control without overtree sprinkler irrigation; 2) sprinkler irrigation applied at midday; and 3) sprinkler irrigation applied at sunset. Fruit color was significantly affected by the cooling irrigation and also by the weather of the particular year. Increased red color and higher anthocyanin content resulted from sprinkler irrigation, especially when applied at sunset. At harvest, anthocyanin content was correlated with a*/b* and hue angle, suggesting that the colorimeter measurements could provide a nondestructive estimate of anthocyanin content.
Edmund J. Ogbuchiekwe and Milton E. McGiffen Jr.
Economic analyses compared the returns of weed control methods for drip and sprinkler irrigated celery (Apium graveolens L. `Sonora'). The nine treatments included an untreated control, cultivation as needed for weed control, a pre-emergent herbicide (trifluralin), and six post-emergent herbicides. The effect of each treatment on weed control, yield, crop value, cost of control, costs for additional hand-weeding, net return, and dollar investment (marginal rate of return) was determined. The treatments that reduced weed populations under drip and sprinkler irrigation also increased yield, net returns, and rate of returns. Effective weed control reduced the additional costs of hand-hoeing the weeds not killed by herbicides, resulting in greater net return. The net returns of weed control were even greater when celery was drip irrigated than when sprinklers were used. In 1998, the sprinkler irrigated field returned $1148 to $3921/ha, compared with -$5984 for the untreated control. Net returns for drip irrigation were much higher, ranging from $3904 to $9187/ha compared with -$8320 for the untreated control. Net returns were also higher in 1999, ranging from $2466 to $5389 when weeds were controlled compared with a net loss of $5710 for the untreated control in the sprinkler irrigated field. The returns on the drip-irrigated field were much higher, from $6481 to $8920 when weeds were controlled, compared with -$8046 for the untreated control. The associated returns for every dollar invested (marginal rate of return) in the non-dominated treatment (more return and lower cost) ranged from 52% to 156% for sprinkler irrigation, and 59% to 144% for drip irrigation in 1998. In 1999, the rate of return for each dollar invested ranged from 104% to 324% for sprinkler and 2.4% to 321% for drip irrigated fields.
Maria Claudia Dussi, David Sugar, Anita Nina Azarenko, and Timothy L. Righetti
Over-tree sprinkler irrigation cooling treatments were applied to `Sensation Red Bartlett' pear trees during the final 30 days of fruit maturity in 1992 and 1993 when orchard air temperatures were >29 °C. Fruit from cooled trees were more red and less yellow than fruit from noncooled trees, resulting in lower hue values by the middle of the harvestable maturity period in both years of study. In 1992, cooled fruit had a greater portion of the fruit surface covered with red blush than fruit that were not cooled. Fruit firmness decreased more rapidly in fruit from cooled trees than in fruit from noncooled trees, indicating advanced maturity. Accordingly, cooled fruit should be harvested earlier than noncooled fruit to maintain postharvest quality. Differences between cooled and noncooled fruit with respect to hue, surface blush, and rate of firmness loss were more pronounced in a warm season requiring frequent cooling than in a cooler season.
Oleg Daugovish, Mark Bolda, Sukhwinder Kaur, Maren J. Mochizuki, Daniel Marcum, and Lynn Epstein
., 2008; Johnson et al., 2006 ; Paredes and Munoz, 2002 ). Because almost all nurseries use sprinkler irrigation, which is conducive for dissemination and infection of Colletotrichum species, nurseries routinely spend over $1200 per ha for fungicides
Emmanuel A. Torres-Quezada, Lincoln Zotarelli, Vance M. Whitaker, Rebecca L. Darnell, Bielinski M. Santos, and Kelly T. Morgan
typically require high volumes of water via sprinkler irrigation after transplanting ( Bish et al., 1997 ). Between 8 and 14 h·d –1 of continuous sprinkler irrigation are used to reduce the air temperature around the strawberry crown and keep leaves moist
Nabila S. Karam and Alexander X. Niemiera
The influence of intermittent and continuous irrigation on the growth, substrate nutrient accumulation and leaching from container-grown marigolds was determined. During a three week period. Tagetes erecta L. `Apollo' in a pine bark substrate received 12 irrigations. Each irrigation allotment was applied intermittently (multiple applications) or continuously (single application). Irrigation occurred when bark reached a targeted water content; irrigation water contained a complete nutrient solution. Leachates were cumulatively collected for each container and analyzed for N; plant dry weight. size, and nutrient composition were determined. Compared to continuously irrigated plants, intermittently irrigated plants had 43% greater root dry weight, 0.7% greater N concentration, and 43% more N leached from the substrate. Shoot mass. size. K, and P concentrations, substrate (pour-through extraction) and leachate N concentration were unaffected by irrigation method. Results demonstrated that. compared to conventional irrigation practices, intermittent irrigation was an effective method to reduce fertilizer effluent and increase N absorption for container-grown plants.
George J. Hochmuth, Salvadore J. Locascio, Stephen R. Kostewicz, and Frank G. Martin
Three irrigation treatments (none, drip, and sprinkler) and eight rowcover treatments were evaluated for their capacity to provide freeze protection for strawberries (Fragaria ×ananassa Duch.) in a split-plot factorial field experiment. The period under study included 20 freeze events, two events with minima of -9.5C and -10.0C. With no freeze protection, up to 93% of the flowers were damaged by freezes. Among sprinkler-irrigated plants, an average of only 10% flowers were damaged due to the freezes. Heavy-weight rowcovers (polyethylene blanket and polypropylene, 30 and 50 g·m-2, respectively) protected strawberry flowers as well as sprinkler irrigation to -4.4C. Early yield (December-January) from unprotected plants was negligible. Early yields from plants protected with a 3.2-mm polyethylene blanket or a 50 g·m-2 polypropylene cover were equal to yields obtained with sprinkler-protected plants. Combinations of sprinkler and certain rowcover treatments provided for better fruit production than either treatment alone. Drip irrigation alone provided no protection from freezes. All strawberry plants recovered from freeze damage and total-season yields were similar with all irrigation methods and rowcovers.