1 / 4

pH near neutral optimal nutrient levels no harmful chemicals, low levels of salts

biological properties. extensive biodiversity plentiful beneficial organisms low pest pressure. Healthy Soil. good tilth surface structure porous and stable no subsoil layers restricting roots good aeration, water storage, drainage. pH near neutral optimal nutrient levels

gitel
Télécharger la présentation

pH near neutral optimal nutrient levels no harmful chemicals, low levels of salts

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. biological properties extensive biodiversity plentiful beneficial organisms low pest pressure Healthy Soil good tilth surface structure porous and stable no subsoil layers restricting roots good aeration, water storage, drainage pH near neutral optimal nutrient levels no harmful chemicals, low levels of salts physical properties chemical properties Figure 8.1. Optimal chemical, biological, and physical properties promote healthy soils.

  2. Plant gives off signals to attract beneficials that attack pests 2 3 Plant increases extrafloral nectar flow as food for adult beneficials 1 Plant produces chemicals that slow pest feeding Figure 8.2. Plants use a number of defense strategies following damage by feeding insects. Modified from unpublished slide of W.J. Lewis.

  3. The plant defense proteins provide resistance to a variety of plant pathogens. defense proteins jasmonate Plant growth- promoting rhizobacteria (PGPR) stimulate plants roots, causing production of plant defense hormones An increase in the hormone salicylic acid causes the plant to produce many types of defense proteins. ethylene salicylic acid Plant hormones jasmonate and ethylene increase throughout the plant and induce resistance to a wide variety of plant pathogens. Disease organisms and nonpathogenic microbes stimulate the plant above- or belowground to produce the hormone salicylic acid. a) systemic acquired resistance (SAR) b) induced systemic resistance (ISR) Figure 8.3. Types of induced resistance to plant diseases. Modified from Vallad and Goodman (2006) by Heather Darby.

  4. Preventive management — preseason through planting time (building internal strengths into the system) Post-planting planned management 1. Crop/plant selection & planting management; habitat conservation & enhancement of field and surroundings Reactive management (if yield or quality goals are not being achieved) 3. In-season pest prevention or management 5. Reactive pest management Overall Goal Optimal crop yield & quality — with high positive and low negative environmental effects • create soil & above- ground conditions for healthy plants with enhanced defenses • stress pests • enhance beneficials Healthy plants with minimal pest damage 6. Reactive soil/nutrient management 2. Build healthy soil (belowground habitat conservation & enhancement) 4. In-season management to reduce crop stress and/or optimize yield and quality Figure 8.4. A whole system approach to soil and crop management at the field level. Modified from Magdoff (2007).

More Related