Efficacy of Solarization and Cabbage Amendment for the Control of Phytophthora spp. in North Florida

The effects of soil solarization with or without cabbage leaf amendments on the survival of Phytophthora spp. were evaluated in several North Florida soils. Soil temperature under solarization treatments reached a maximum of 47°C at a 10-cm depth, but only 41°C at 25 cm. Solarization with a clear, gas-impermeable film was as effective as methyl bromide in reducing populations of P. nicotianae at a 10-cm depth but had no effect on populations at a depth of 25 cm. Populations of P. capsici after solarization with either a clear, low-density polyethylene or a clear, gas-impermeable film were similar to methyl bromide treatment at the 10-cm depth, while at the 25-cm depth, no reduction in populations was observed. Incorporation of cabbage into the soil at a rate of 6.6 to 8.9 kg/m2 did not enhance the effectiveness of solarization in reducing populations of either Phytophthora sp.

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Purple Nutsedge Control with Allyl Isothiocyanate under Virtually Impermeable Film Mulch

Weed Technology ◽

10.1614/wt-d-13-00095.1 ◽

2014 ◽

Vol 28 (1) ◽

pp. 200-205 ◽

Cited By ~ 5

Author(s):

Sanjeev K. Bangarwa ◽

Jason K. Norsworthy

Keyword(s):

Methyl Bromide ◽

Field Experiments ◽

Standard Treatment ◽

Allyl Isothiocyanate ◽

Low Density Polyethylene ◽

Vegetable Production ◽

Low Density ◽

Purple Nutsedge ◽

Treated Soil ◽

Polyethylene Mulch

Nutsedge control is challenging in commercial vegetable production in the absence of methyl bromide, and therefore, an effective alternative is needed. This study investigated allyl isothiocyanate (ITC) as a methyl bromide alternative for purple nutsedge control under polyethylene-mulch. Greenhouse experiments were conducted to compare the retention of allyl ITC in treated soil (3,000 nmol g−1) under low-density polyethylene (LDPE) and virtually impermeable film (VIF) mulches. Field experiments were conducted to evaluate the effectiveness of allyl ITC (6 rates: 0, 15, 75, 150, 750, 1500 kg ai ha−1) under VIF mulch against purple nutsedge. Additionally, a standard treatment of methyl bromide+chloropicrin (67 : 33%) at 390 kg ai ha−1under LDPE mulch was included for comparison. In the greenhouse experiment, the predicted half-life of allyl ITC under LDPE and VIF mulch was 0.15 and 0.59 d, respectively. In the field experiment, it was predicted that allyl ITC at 1,240 and 1,097 kg ha−1under VIF mulch is required to control purple nutsedge shoot and tubers equivalent to methyl bromide + chloropicrin at 4 wk after treatment (WAT). It is concluded that allyl ITC under VIF mulch would need to be applied at 2.8 to 3.2 times the standard treatment of methyl bromide + chloropicrin under LDPE mulch for commercially acceptable purple nutsedge control.

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Reduction of Phytophthora cactorum in Strawberry Fields by Trichoderma spp. and Soil Solarization

Plant Disease ◽

10.1094/pdis-91-2-0142 ◽

2007 ◽

Vol 91 (2) ◽

pp. 142-146 ◽

Cited By ~ 23

Author(s):

M. Porras ◽

C. Barrau ◽

F. T. Arroyo ◽

B. Santos ◽

C. Blanco ◽

...

Keyword(s):

Disease Control ◽

Methyl Bromide ◽

Untreated Control ◽

Field Experiments ◽

Low Density Polyethylene ◽

Low Density ◽

Phytophthora Cactorum ◽

Trichoderma Spp ◽

Soil P ◽

Polyethylene Mulch

Field experiments were conducted in southwest Spain for three consecutive years from 2000 to 2003 to evaluate the effectiveness of solarization and Trichoderma spp., alone and combined, in reducing Phytophthora cactorum soil populations and consequently leather rot on fruit of strawberry plants. Plots (12.5 by 3.3 m), never treated with methyl bromide, were naturally infested by P. cactorum. Solarization was conducted during the summer, using clear 50-µm low-density polyethylene mulch. Trichoderma spp. were applied via drip and dip, adding to the soil 7 days before planting (108 conidia/m2), and strawberry roots were dipped in a suspension of Trichoderma spp. (106 conidia/ml) prior to planting. Solarization reduced the soil P. cactorum population 100% in year 1, 47% in year 2, and 55% in year 3 relative to the untreated control. Trichoderma spp. applications reduced soil populations of P. cactorum and reduced leather rot incidence 76.6% in year 1 and 33.8% in year 2 compared with the untreated control. The combination of solarization and Trichoderma spp. reduced P. cactorum soil population the most each year, 88.9% in January 2001, 97.6% in 2002, and 99.0% in 2003. The very promising effect of Trichoderma spp. and solarization against P. cactorum indicates that there may be future alternatives to traditional chemicals for disease control.

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