most time-consuming task (data not shown). Irrigation and pruning were tied for second most time-consuming tasks, followed by debris removal (data not shown). Due to the different conditions on these roofs, the time spent on irrigation varied from zero
, without increasing pH significantly or providing excessive soluble salts and mineral N. For example, in Oregon, yard debris composts were applied as mulch (not incorporated) in two separate trials on a silt loam soil ( Sullivan and Bell, 2015 ; Sullivan
Abstract
Bacterial pathogens cause destructive diseases on many important vegetable crops throughout the world. Satisfactory chemical control measures for bacterial pathogens have not been achieved. Recommended control measures are: use of disease-free seed and transplants; hot water treatment of seed if feasible; suitable rotations; deep plowing of plant debris; and use of resistant cultivars if available (13, 50, 51, 53, 73, 75, 76, 77).
planting, yard debris compost (≈2 cm deep-centered on the row; 76 m 3 ·ha –1 ) and douglas fir sawdust (≈5 cm deep; 200 m 3 ·ha –1 ) were incorporated before forming the raised beds in Sept. to Oct. 2006. Immediately after planting, the beds were first
.) Franco var. menziesii ; 360 m 3 ·ha −1 ]; b) a 4-cm-deep layer of municipal yard-debris compost (152 m 3 ·ha −1 ) covered by 5-cm-deep douglas fir sawdust (200 m 3 ·ha −1 ) (compost + sawdust); and c) weed mat [black, woven polyethylene groundcover
The bacterium Xanthomonas campestris pv. campestris (Xcc), causal agent of black rot disease in crucifers was tagged with the luciferase gene complex of the marine bacterium Vibrio fisheri. The growth of the bioluminescent strain in plants and the environment can be monitored by its light emissions. Susceptible cabbage plants were either mist, wound or debris inoculated in the field, soil was inoculated with debris or with suspension culture of genetically engineered Xcc. Plant, soil and air samples will be taken at biweekly intervals to monitor the spread of the bioluminescent bacterium within as well as outside the environmental release site. The transfer of exotic DNA to other bacteria in the environment will also be studied.
Abstract
Use of certain pesticides over a 3-year period caused a marked build-up of plant debris (thatch) of ‘Kentucky’ bluegrass (Poa pratensis L.) turf above the soil surface. Applications of the chlorinated hydrocarbon insecticides, dieldrin and chlordane, resulted in a thatch layer of 20 mm or more. The use of the carbamate insecticide, carbaryl, caused an average match thickness of 1.3 mm. The plots that received no insecticides or the mercuric fungicide, phenyl mercuric acetate (PMA), had no measurable thatch. The match depths were closely associated with plant debris wt.
As the no. of earthworm burrows increased, the amount of thatch decreased. Where earthworms were present to any extent, thatch was virtually non-existent.
Solid particles in water such as sand, silt, clay, or organic debris can clog drip irrigation systems. Filters that remove these particles from the water are necessary, but expensive, for small-scale or part-time farmers. A falter that is functionally similar to commercial units can be built from a steel barrel and common plumbing supplies for about $100. Components and instructions to build such a falter are presented here.
With the cooperation of six commercial greenhouses (five in Colorado, one out of state), rooted poinsettia cuttings and bedding plant plugs were collected and analyzed for Pythium and Rhizoctonia, two common root rotting pathogens in Colorado greenhouses. Samples of plant, soil, and water debris were taken from four greenhouses, as well as samples of growing media ready for use. These were also analyzed for Pythium and Rhizoctonia. Fungi recovered from the plant, debris, or growing media samples were identified, grown in pure culture, and introduced into susceptible plants (Vinca minor) in pathogenicity studies. Neither pathogen was isolated from the rooted poinsettia cuttings tested. Pythium was not found in any of the plug material or in growing media. Rhizoctonia solani was found in 16% of the plug samples and 7% of the growing media samples tested. Debris from greenhouse floors yielded four species of Pythium as well as Rhizoctonia solani. Isolates of each fungus were able to colonize, but not adversely affect, inoculated plants in pathogenicity studies. It appears that disease causing organisms that have potential to decrease plant quality and growth are already present in the greenhouse. Control of root rotting pathogens can best be carried out by relying heavily on sanitation measures.
., 2006 ), whereas it was within this range in the weed mat treatment throughout the study ( Table 3 ). Larco et al. (2013a) found lower soil pH under weed mat mulch than under a yard-debris compost + sawdust mulch in organic blueberry. However, use of a