scholarly journals Effects of Irrigation and Tillage on Temporal and Spatial Dynamics of Sclerotinia minor Sclerotia and Lettuce Drop Incidence

2003 ◽  
Vol 93 (12) ◽  
pp. 1572-1580 ◽  
Author(s):  
B. M. Wu ◽  
K. V. Subbarao
Keyword(s):  
Drip Irrigation ◽  
Spatial Dynamics ◽  
Conventional Tillage ◽  
Furrow Irrigation ◽  
Subsurface Drip Irrigation ◽  
Sclerotinia Minor ◽  
Minimum Tillage ◽  
Lettuce Drop ◽  
Temporal And Spatial ◽  
Subsurface Drip

The temporal and spatial dynamics of Sclerotinia minor sclerotia and the resulting incidence of lettuce drop were studied under furrow irrigation with conventional tillage and subsurface-drip irrigation with minimum tillage during 1993–95. Lettuce crops were grown each year during the spring and fall seasons. All plants were inoculated immediately after thinning in the spring of 1993. Grids of 24 contiguous quadrats (1 by 1 m2) were demarcated in the centers of each 150-m2 plot. Lettuce drop incidence in each quadrat was evaluated each season prior to harvest. One soil sample (100 cm3) was collected from each quadrat at harvest and after tillage prior to planting of the next crop for both spring and fall crops and assayed for S. minor sclerotia using wet sieving. Lloyd's index of patchiness, the β-binomial distribution, and variance of moving window averages were used to evaluate the spatial patterns of sclerotia and lettuce drop incidence under the two irrigation systems and associated tillage treatments. Disease incidence remained significantly higher under furrow irrigation than under subsurface-drip irrigation throughout the study period, and was significantly higher on fall crops than on spring crops. Under furrow irrigation, the number of sclerotia at the end of a crop season increased significantly over that at the beginning of the season, but no significant changes were detected over years. In contrast, the number of sclerotia within a single season did not increase significantly under subsurface drip irrigation, nor was year-to-year accumulation of sclerotia statistically significant. The degree of aggregation of sclerotia increased significantly during a cropping season under furrow irrigation, but not under subsurface drip irrigation. The conventional tillage after harvest under furrow irrigation decreased the degree of aggregation of sclerotia after each season, but the distribution pattern of sclerotia under subsurface-drip irrigation changed little by the associated minimum tillage. Spatial pattern analyses suggested that the aggregation of S. minor sclerotia occurred at a scale of no more than 1 m, and distribution of diseased lettuce plants was random at a scale larger than 1 m. The combination of fewer sclerotia produced by each crop and its unaltered distribution under subsurface drip irrigation and associated minimum tillage makes it a valuable cultural practice for lettuce drop management.

scholarly journals Mechanisms of Subsurface Drip Irrigation-Mediated Suppression of Lettuce Drop Caused by Sclerotinia minor

1998 ◽  
Vol 88 (3) ◽  
pp. 252-259 ◽  
Author(s):  
A. A. Bell ◽  
L. Liu ◽  
B. Reidy ◽  
R. M. Davis ◽  
K. V. Subbarao
Keyword(s):  
Soil Moisture ◽  
Drip Irrigation ◽  
Soil Microflora ◽  
Sampling Time ◽  
Furrow Irrigation ◽  
Subsurface Drip Irrigation ◽  
Microbial Populations ◽  
Irrigation Methods ◽  
Lettuce Drop ◽  
Subsurface Drip

Subsurface drip irrigation and associated mandatory minimum tillage practices significantly reduced the incidence of lettuce drop (Sclerotinia minor) and the severity of corky root on lettuce compared with furrow irrigation and conventional tillage. Three possible mechanisms for the drip irrigation-mediated disease suppression were examined in this study: qualitative and quantitative differences in the soil microflora under furrow and subsurface drip irrigation; their antagonism and potential bio-control effects on S. minor; and the physical distribution of soil moisture and temperature relative to the two irrigation methods. To determine if the suppressive effects under subsurface drip irrigation were related to changes in soil microflora, soils were assayed for actinomycetes, bacteria, and fungi during the spring and fall seasons. The effects of the irrigation methods on microbial populations were nearly identical during both seasons. In the spring season, the total number of fungal colonies recovered on potato dextrose agar amended with rose Bengal generally was greater in soils under drip irrigation than under furrow irrigation, but no such differences were observed during the fall. Numbers of actinomycetes and bacteria were not significantly different between irrigation methods during either season. No interaction between sampling time and irrigation methods was observed for any of the microbial populations during both seasons. Thus, the significant effect of sampling time observed for actinomycete and bacterial populations during the spring was most likely not caused by the irrigation treatments. There were also no qualitative differences in the three groups of soil microflora between the irrigation treatments. Even though some fungal, actinomycete, and bacterial isolates suppressed mycelial growth of S. minor in in vitro assays, the isolates came from both subsurface drip- and furrow-irrigated soils. In in planta assays, selected isolates failed to reduce the incidence of drop in lettuce plants. The soil moisture under subsurface drip irrigation was significantly lower at all depths and distances from the bed center after an irrigation event than under furrow irrigation. The soil temperature, in contrast, was significantly higher at both 5 and 15 cm depths under drip irrigation than under furrow irrigation. The suppression of lettuce drop under subsurface drip irrigation compared with furrow irrigation is attributed to differential moisture and temperature effects rather than to changes in the soil microflora or their inhibitory effects on S. minor.

scholarly journals Comparison of Lettuce Diseases and Yield Under Subsurface Drip and Furrow Irrigation

1997 ◽  
Vol 87 (8) ◽  
pp. 877-883 ◽  
Author(s):  
K. V. Subbarao ◽  
J. C. Hubbard ◽  
K. F. Schulbach
Keyword(s):  
Downy Mildew ◽  
Drip Irrigation ◽  
Block Design ◽  
Furrow Irrigation ◽  
Subsurface Drip Irrigation ◽  
Corky Root ◽  
Salinas Valley ◽  
Lettuce Drop ◽  
Irrigation Treatments ◽  
Subsurface Drip

Subsurface drip and furrow irrigation were compared on lettuce (Lactuca sativa) cvs. Salinas and Misty Day for yield and incidence and severity of three important diseases of lettuce in the Salinas Valley, CA. Experiments were conducted between 1993 and 1995 during the spring and fall seasons. The diseases examined included lettuce drop (Sclerotinia minor), downy mildew (Bremia lactucae), and corky root (Rhizomonas suberifaciens). Replicated plots of subsurface drip and furrow irrigation were arranged in a randomized complete-block design. All plants were inoculated with S. minor at the initiation of the experiment during the 1993 spring season. Plots were not inoculated for downy mildew and corky root during any season nor were the plots reinoculated with S. minor. During each season, all plots were sprinkler irrigated until thinning, and subsequently, the irrigation treatments were begun. The furrow plots were irrigated once per week, and the drip plots received water twice per week. The distribution of soil moisture at two soil depths (0 to 5 and 6 to 15 cm) at 5, 10, and 15 cm distance on either side of the bed center in two diagonal directions was significantly lower in drip-irrigated compared with furrow-irrigated plots. Plots were evaluated for lettuce drop incidence and downy mildew incidence and severity at weekly intervals until harvest. Corky root severity and yield components were determined at maturity. Lettuce drop incidence and corky root severity were significantly lower and yields were higher in plots under subsurface drip irrigation compared with furrow irrigation, regardless of the cultivar, except during the 1994 fall season. Incidence and severity of downy mildew were not significantly different between the two irrigation methods throughout the study. The differential microclimates created by the two irrigation treatments did not affect downy mildew infection, presumably because the mesoclimate is usually favorable in the Salinas Valley. Subsurface drip irrigation is a viable, long-term strategy for soilborne disease management in lettuce in the Salinas Valley.

Role of irrigation and wastewater reuse: comparison of subsurface irrigation and furrow irrigation

2004 ◽  
Vol 50 (2) ◽  
pp. 61-68 ◽  
Author(s):  
C. Choi ◽  
I. Song ◽  
S. Stine ◽  
J. Pimentel ◽  
C. Gerba
Keyword(s):  
Drip Irrigation ◽  
Arid Regions ◽  
Irrigation System ◽  
Soil Surface ◽  
Furrow Irrigation ◽  
Subsurface Drip Irrigation ◽  
Vegetable Crops ◽  
Viral Contamination ◽  
Subsurface Drip ◽  
Semi Arid

Two different irrigation systems, subsurface drip irrigation and furrow irrigation, are tested to investigate the level of viral contamination and survival when tertiary effluent is used in arid and semi-arid regions. The effluent was injected with bacteriophages of PRD1 and MS2. A greater number of PRD1 and MS2 were recovered from the lettuce in the subsurface drip-irrigated plots as compared to those in the furrow-irrigated plots. Shallow drip tape installation and preferential water paths through cracks on the soil surface appeared to be the main causes of high viral contamination in subsurface drip irrigation plots, which led to the direct contact of the lettuce stems with the irrigation water which penetrated the soil surface. The water use efficiency of the subsurface drip irrigation system was higher than that of the furrow irrigation system. Thus, subsurface drip irrigation is an efficient irrigation method for vegetable crops in arid and semi-arid regions if viral contamination can be reduced. Deeper installation of drip tapes, frequent irrigations, and timely harvests based on cumulative heat units may further reduce health risks by ensuring viral die-off under various field conditions.

scholarly journals Productivity of Onions Using Subsurface Drip Irrigation versus Furrow Irrigation Systems with an Internet Based Irrigation Scheduling Program

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Juan Enciso ◽  
John Jifon ◽  
Juan Anciso ◽  
Luis Ribera
Keyword(s):  
Drip Irrigation ◽  
Irrigation Scheduling ◽  
Furrow Irrigation ◽  
Subsurface Drip Irrigation ◽  
Irrigation Systems ◽  
Use Efficiency ◽  
Subsurface Drip ◽  
Selection Of ◽  
Commercial Field ◽  
Plot Design

Selection of the proper irrigation method will be advantageous to manage limited water supplies and increase crop profitability. The overall objective of this study was to evaluate the effect of subsurface drip irrigation (SDI) and furrow irrigation on onion yield and irrigation use efficiency. This study was conducted in two locations, a commercial field and a field located at the Texas A&M AgriLife Research Center in Weslaco, TX. This study was conducted as a split-plot design for both sites with two treatments (SDI and furrow irrigation) and three replications per treatment. The total onion yield obtained with the SDI systems was more than 93% higher than the yield obtained with furrow irrigation systems. The large onion size was 181% higher for the SDI system than the furrow system in both sites. The colossal size yield was also higher. At one site colossal yield was 206% higher than furrow, while at another site furrow yielded no colossal onions and SDI had some production. It was concluded that drip irrigation systems more than double yields and increased onion size while using almost half of the water. This was due to SDI allowing for more frequent and smaller irrigation depths with higher irrigation efficiency than furrow irrigation systems.

Weed Control, Yield, and Quality of Processing Tomato Production under Different Irrigation, Tillage, and Herbicide Systems

2006 ◽  
Vol 20 (4) ◽  
pp. 831-838 ◽  
Author(s):  
Kipp F. Sutton ◽  
W. Thomas Lanini ◽  
Jefferey P. Mitchell ◽  
Eugene M. Miyao ◽  
Anil Shrestha
Keyword(s):  
Drip Irrigation ◽  
Conservation Tillage ◽  
Irrigation Treatment ◽  
Furrow Irrigation ◽  
Subsurface Drip Irrigation ◽  
Tillage Systems ◽  
Processing Tomato ◽  
Irrigation Treatments ◽  
Subsurface Drip ◽  
Germination And Growth

A field experiment was conducted near Davis, CA, during the 2003 and 2004 summer growing seasons to compare weed control, yield, and fruit quality in different irrigation and tillage systems in processing tomato. Trial design was a subplots with the main plots as subsurface drip irrigation or furrow irrigation, subplots were standard tillage or conservation tillage, and sub-subplots were herbicide or no herbicide. The hypothesis was that subsurface drip irrigation could limit surface soil wetting and thus inhibit germination and growth of weeds equal to or better than standard tillage and/or herbicides. In both 2003 and 2004, weed densities in the subsurface drip irrigation treatments were over 98% lower than the levels in furrow irrigation treatments. In addition, weed densities were lower in the subsurface drip–conservation till–no herbicide treatment than in any of the furrow irrigation treatments, including the furrow irrigation–standard tillage–herbicide treatments. The time required for a hand-hoeing crew to remove weeds was 5 to 13 times greater in furrow irrigation treatments compared to subsurface drip irrigation treatments. Weed biomass on beds at tomato harvest was 10 to 14 times greater in the furrow systems as compared to the subsurface drip irrigation systems. These results demonstrate the effectiveness of subsurface drip irrigation in controlling weed germination and growth, compared to tillage or herbicide applications. Tomato yield was higher in the subsurface drip irrigation treatment compared to furrow irrigation in 2004. Herbicide treatment increased yield in 2004, but only in the furrow irrigation treatment in 2003. Fruit brix level was not related to treatment in 2003, but was lower in the subsurface drip irrigation plots in 2004. These results indicate that subsurface drip irrigation can reduce weed competition in conservation tillage systems, without requiring herbicide applications.

scholarly journals Response of Onion Yield, Grade, and Financial Return to Plant Population and Irrigation System

HortScience ◽  
2015 ◽  
Vol 50 (9) ◽  
pp. 1312-1318 ◽  
Author(s):  
Clinton C. Shock ◽  
Erik B.G. Feibert ◽  
Alicia Riveira ◽  
Lamont D. Saunders
Keyword(s):  
Drip Irrigation ◽  
Irrigation System ◽  
Plant Population ◽  
Furrow Irrigation ◽  
Subsurface Drip Irrigation ◽  
Irrigation Systems ◽  
Plant Populations ◽  
Financial Return ◽  
Economic Return ◽  
Subsurface Drip

Onion (Allium cepa) plant population is an important factor in total yield and bulb size, both of which can influence economic return to growers. Different onion bulb marketing opportunities influence the plant populations that growers should target. With the transition from furrow irrigation to a drip irrigation system, growers have doubts as to the onion population that should be planted to assure favorable economic outcomes. Onions were grown on silt loam at the Oregon State University Malheur Experiment Station, Ontario, OR in 2011 and 2012 following bread wheat (Triticum aestivum L.) each year. Long-day onion cultivars Vaquero, Esteem, Barbaro, and Sedona were planted heavily and thinned to nominal plant populations between 222,000 and 593,000 plants/ha under furrow irrigation, subsurface drip irrigation, and “intense bed” subsurface drip irrigation. The intense bed configuration had 50% more rows of onions with three drip tapes per 1.94-m bed instead of two tapes. The experiment had a randomized complete block split-split-plot design with six replicates. Irrigation systems were the main plots, cultivars the split plots, and plant populations the split-split plots. Onion yield and grade responses to plant population for each cultivar and each planting system were determined by regression of yield and grade on the actual onion plant stands. In general, there were few differences among irrigation systems or interactions among irrigations systems, cultivars, and plant populations. Averaging over cultivars, total and marketable bulb yield out of storage increased with plant population, whereas the bulb diameters decreased with plant population. Average marketable yield was 119 Mg⋅ha−1 over the 2 years. Average yield of colossal bulbs >102 mm in diameter decreased with increasing plant population. In 2011, estimated gross economic return increased linearly with plant population, offset in part by increasing seed cost. In 2012, estimated economic return responded quadratically to plant population with maximum return of $45,357/ha at 419,000 plants/ha.

The Role of Irrigation and Wastewater: Comparison of Subsurface Drip Irrigation and Furrow Irrigation

2003 ◽  
Author(s):  
Inhong Song ◽  
Scott Stine ◽  
Jose Pimentel ◽  
Christopher Y. Choi ◽  
Charles Gerba
Keyword(s):  
Drip Irrigation ◽  
Furrow Irrigation ◽  
Subsurface Drip Irrigation ◽  
Subsurface Drip
Sign in / Sign up

Export Citation Format

Share Document