Search Results

Abstract

Pepper (Capsicum frutescens L.) and summer squash (Cucurbita pepo var. melopepo (L.) Alef.) were grown in immediate succession in undisturbed beds using trickle irrigation with various treatments. Highest combined yield in metric tons/ha for both crops was obtained with film mulch + soil fumigation (117.6) followed by film mulch (112.3), soil fumigation (93.4) and control (69.0), respectively. Yield from the second crop was negatively correlated (r=−.87) with the degree of plant infection with root-knot nematode (Meloidogyne incognita (Kofoid & White) Chitwood). Intensive production in this manner allows fixed costs to be defrayed over two crops thus increasing the magnitude of return per dollar invested. Multiple cropping of pepper and squash with trickle irrigation has an excellent potential in south Georgia provided nematodes and other soil-borne pathogens can be adequately controlled.

Abstract

A 2-year field study was conducted on a fine sandy loam soil near Vincennes, Ind., to evaluate tomato (Lycopersicon esculentum Mill. cv. Sunny) response to trickle irrigation and black polyethylene mulch. Use of trickle irrigation resulted in higher petiole P and B and lower Zn concentrations than using no irrigation. Trickle-irrigated soils had lower soil NH₄-N, NO₃-N, and K and higher Mg concentrations than non-irrigated soils. Soil NH₄-N, NO₃-N, and Mg concentrations were higher in soils mulched with polyethylene than in soils without mulch. The use of trickle irrigation increased plant height, whereas polyethylene mulch increased plant spread and dry matter production. Early, late, and total yields were improved with all trickle irrigation and polyethylene mulch treatments. Total yields were 66%, 70%, and 123% greater for plants grown with polyethylene mulch, trickle irrigation, and polyethylene mulch plus trickle irrigation, respectively, than control plants.

Abstract

Response of hybrid summer squash (Cucurbita pepo L.) cvs. Seneca Zucchini and Zucchini Elite to trickle irrigation and black plastic mulch was evaluated in field studies conducted on a southwestern Indiana loamy sand soil during 1982 and 1983. Trickle irrigation and plastic mulch each increased plant growth, early bloom, and yield. Trickle irrigation reduced percentage of culls. Plant growth was correlated negatively with days to bloom after planting. Days to bloom were correlated negatively with yield; the early-blooming plants tending to yield more than the late-blooming plants. Significantly higher yields are possible with current cultivars using trickle irrigation and plastic mulch.

Abstract

Peach trees (Prunus persica (L.) Batsch cv. Redglobe) were trickle-irrigated at 3 rates using open pan evaporation as a basis for calculating theoretical irrigation needs from 1973-1976 beginning when trees were 6-years-old. Although above average rainfall was received about 65% of the time, trickle irrigation (1½ times theoretical needs) increased yield per tree, fruit size, number of fruit buds per tree, and trunk diameter over non-irrigated trees. Trickle irrigation at 1½ the calculated rate increased average yield per tree, fruit size, and trunk diameters over trees sprinkle-irrigated once before harvest.

Abstract

Trickle irrigation studies often require different water application rates. The design and construction of trickle systems for randomized studies can be difficult and expensive if they involve separate timers, solenoids, valves, and/or irrigation lines for each treatment. One possible solution to this problem is to design the system so that only the emitters are used to regulate the flow of water within each test group. Such a system can be controlled by a single timer with only one lateral line needed for each row.

Abstract

The minimum water requirement to produce the greatest number of marketa- bie cut flowers of Chrysanthemum × morifolium Ramat. ‘Manatee Yellow Iceberg’ was 35 cm with trickle irrigation, a 91% reduction in water uses as compared to overhead irrigation systems. Linear responses for fresh weight, dry weight, leaf area, leaf number, and flower number between 13.6 and 40.7 cm of water supplied during production indicated that an additional 6 cm of water would improve marketable stem's quality.

Two field experiments were conducted with subsurface trickle-irrigated romaine lettuce (Lactuca sativa L. cv. Parris Island Cos) during the 1990–92 winter growing seasons in southern Arizona. The objectives were to determine 1) yield and quality response to varying combinations of soil water tension (SWT) and N fertilizer, 2) seasonal patterns of N uptake, and 3) unutilized fertilizer N. During 1990–91, N rates were 35, 120, and 205 kg·ha^–1. During 1991–92, the experiment was factorial with N levels from 50 to 300 kg·ha^–1 and target SWT levels of 7.0 and 4.0 kPa. Unutilized fertilizer N was the difference between fertilized and nonfertilized plots in total N inputs not harvested in the crop. When excessive irrigation was not applied (SWT between 6.5 and 7.4 kPa), 95% of the maximum crop yield and yield quality (head length and fresh mass) response occurred at N rates of 156 to 193 kg·ha^–1, with unutilized fertilizer N <60 kg·ha^–1. Excessive irrigation (4.6 kPa) resulted in lower yields and yield quality and higher unutilized fertilizer N. Romaine accumulated >74% of its total N uptake in the 38 days before harvest. Unutilized fertilizer N increased sharply when adequate N and water rates were exceeded. These results suggest that a target SWT of no wetter than 6.5 kPa is appropriate for subsurface trickle-irrigated romaine lettuce.

The purpose of this project was to investigate the use of evapotranspiration (ET) as a guideline for trickle irrigation timing in field-grown day-neutral `Tristar' strawberry. Proper management of trickle irrigation would allow optimum yields and quality with minimum water inputs. A randomized complete block field design with four replications was used at the ISU Horticulture Station in central Iowa. Irrigation treatments were based on % of ET and number of applications per week. The four treatments included: 30, 60, and 90 % of ET applied once per week (1X) and 30% of ET applied 3 times per week (3X). Total yield data (kg of fruit per season) indicated the 30% of ET (3X) treated plants yielded 15% more fruit than the 30% of ET (1X) plants. Berry number was 14% greater from plants receiving the 30% of ET (3X) treatment than from those receiving the 30% of ET (1X) treatment. Average berry weights for the entire growing season were similar among all treatments.

Abstract

Strawberries (Fragaria × ananassa Dutch.) were grown during 2 seasons to evaluate 5 N sources and 2 times of N and K application using trickle irrigation with N and K rates of 134 and 149 kg ha⁻¹, respectively. Fruit yields were influenced by significant interactions between N-source and time of N and K application during both seasons. With 100% of the N and K applied preplant, marketable fruit number and weight were significantly greater with sulfur coated urea (SCU) or isobutylidene diurea (IBDU) than with urea, NH₄NO₃ or KNO₃ + Ca(NO₃)₂ as the N sources. With 40% of the N from the above 5 sources applied preplant and 60% of the N and K supplied with the trickle irrigation from NH₄NO₃ + K₂SO₄ or KNO₃ + Ca(NO₃)₂, production was similar with all N sources. Leaf tissue N and K concentrations were not influenced consistently by N source. During both seasons, leaf N concentrations were higher with the split than with the 100% preplant treatments.

Abstract

Root length densities (cm·cm⁻³) of ‘VF145-B7879’ and ‘UC-82B’ tomatoes (Lycopersicon esculentum Mill.) were determined at three depths and four locations across the planting bed for traveling trickle irrigation treatments applied at 35%, 70%, and 105% of evapotranspiration (ET). Cultivars did not differ in root length densities or in their effect on soil moisture levels. Root length density and soil moisture decreased with soil depth. Although soil moisture was greater in the furrows, the zones of highest root concentration were between the rows of plants and along the edge of the beds. Greater root length density was found in the 35% ET than in the 70% or 105% ET irrigation rate. Chemical names used: 2-(α-naphthoxy)-N,N-diethylpropionamide (napropamide); S-propyl butylethylthiocarbamate (pebulate).