Vegetables

The integration of foliar applied seaweed and fish products into the fertility management of organically grown sweet peppers

Organic vegetable growers regularly use sea-based products, such as seaweed extracts and fish emulsions, as foliar fertilizers. The effective use and the economic value of these products in organic agriculture have yet to be verified by scientific research. In these studies, we examined the effects of foliar applied seaweed and fish products on sweet bell peppers grown at three different soil fertility levels

Improving the quality of organic herb production and marketing

Farmers interested in transitioning some or all of their land into organic production need information regarding the best management practices for these systems. Soil fertility and weed management strategies are imperative for optimum plant growth and yields. Current research in organic herb production at Iowa State University has included investigations into certified organic methods of fertilization and use of organic mulches for weed suppression.

The Effects of Green Manure, Compost, and Feather Meal on Soil Nitrogen Dynamics, Beneficial Soil Microorganisms, and Bell Pepper Yield

Many organic growers utilize a preceding cover crop or diverse types of organic fertilizer materials for fertility management. Cover crops are one of the most economical sources of organic nitrogen and provide additional potential benefits for succeeding crops. Time or market constraints and the need to intensively farm high value land may limit the use of cover crops and increase the need to utilize organic fertilizer sources of plant nutrients.

Maintaining agroecosystem health in an organic strawberry/vegetable rotation system

Continued growth of organic strawberry and vegetable production in California faces two challenges: soil-borne disease management without use of synthetic chemical fumigants, and fertility management to optimize fertility input use while ensuring protection of vulnerable habitats.
 
The goal of this project is to demonstrate effects of diverse organic strawberry/vegetable rotations and integrated ecological practices on agroecosystem health.
 

Shade-covered high tunnels for summer production of lettuce and leafy greens

Most varieties of greens do not grow throughout the market season in the Midwest because of the 85-degree-plus weather, which persists for much of July, August and September. High temperatures (and resulting problems with dormancy and rapid drying of soil) result in poor crop establishment, and bitterness and bolting of lettuce. Other leafy greens are severely affected by high insect populations. The ability to extend the greens season through the summer heat would benefit local growers while meeting a consumer need at peak market times.

Phytoestrogen content of conventionally and organically grown soybeans

Soy-based foods have been the subject of recent research due to increasing evidence that soy phytoestrogens may modify the pathogenesis of some hormone-dependent and hormoneindependent diseases'. Studies have shown the isoflavones genistin and daidzin may have beneficial effects on menopausal symptoms', osteoporosis3 , and coronary heart disease 4-5. These findings have led to clinical recommendations of greater dietary intake of phytoestrogen-containing soy products.

Nutrient analysis of organic strawberries: effect of cultivars and mycorrhizal inoculations

Objectives 1. Demonstrate the relative nitrogen performance of standard California cultivars grown under organic management. 2. Determine if a commercial arbuscular mycorrhizae (AM) inoculant could provide mineral nutritional benefit, especially on phosphorus, to the cultivars being tested in the first objective. 3. Provide information that will aid organic strawberry producers in fertility management.

Plant mobilization of trace organochlorine residues in vegetable cropping systems

Soil testing has long been a part of Organic Certification. As part of the certification process, each grower must submit soil tests for lab analysis. The soil is subjected to chromatography tests to determine the extent of contamination by organochlorine insecticides. These compounds classify a wide range of noxious agricultural pesticides, many with half lives exceeding twenty years. Unfortunately for conventional and organic growers, even at hardly detectable levels these contaminants are finding their way into agricultural products.

Impact of Disease Suppressive Composts on Organic Vegetable Quality Composition and Yield

The goal of this research was to initiate studies on compost effects on severity of common soil borne diseases and to characterize changes plant growth due to improved nutrient availability and soil microbial activity with compost application in organic production systems. 

Project Objectives

-Analyze several animal manure-based, organic-approved compost products for suppression of important soil-borne pathogens of vegetable crops in the Northeast

-Determine applicability of a farmer-based test kit for assessment of compost maturity to predict suppressiveness

A grower-managed biorational program for artichoke pests (BIORAPP) on the north central California coast

A native egg parasite, Trichogramma thalense, was mass-reared in the laboratory and released a maximum of thirteen times against the eggs of the artichoke plume moth (Platyptilia carduidactyla) in three 5-acre biointensive artichoke production fields on the northern Santa Cruz/San Mateo County coast in 1998 and again in 1999-2000.