The standard fumigated beds had generally low nitrate nitrogen. At all sampling periods, the ammonium nitrate was lower than the RABETS target value of 14 ppm . The RABETS target of 30 ppm available phosphorus was maintained in all of the media treatments at both sites .Anaerobic soil disinfestation , a non-chemical alternative to methyl bromide, was developed in Japan and the Netherlands to control soilborne pathogens and nematodes in strawberries and vegetables. Anaerobic soil disinfestation integrates the principles of solarization and flooding in situations where neither method alone is effective or feasible. Anaerobic soil conditions are created by incorporating readily available carbon sources into topsoil, covering the soil with plastic tarp and irrigating to field capacity. The tarp is left in place to maintain soil moisture above field capacity and to sustain anaerobic conditions. Anaerobic decomposers respire using the added carbon, which results in a buildup of anaerobic byproducts that are toxic to pathogens . These byproducts degrade rapidly once the tarp is removed or holes are punched through the tarp for planting. Studies were conducted during 2008 to 2011 in an attempt to optimize anaerobic soil disinfestation for California strawberry and Florida vegetable production systems. Overall, it was very effective in suppressing Verticillium dahliae in soils, planting gutter and it resulted in 85% to 100% of the marketable fruit yield observed with fumigated controls in coastal California strawberries when 9 tons per acre of rice bran was preplant incorporated and 3 to 4 acre-inches of irrigation was applied in sandy loam to clay loam soils .

In the semitropical climate of Florida, when composted broiler litter and heavy black strap molasses were incorporated as substrate, anaerobic soil disinfestation treatments provided good control of nutsedge and excellent control of grasses, broadleaf weeds, Phytophthora capsici and Fusarium oxysporum f. sp. lycopersici . In the cooler conditions of the Central Coast, however, anaerobic soil disinfestation may not provide effective control of many weed species . To ensure consistency of pest suppression across varying locations, the effects of soil temperatures and treatment length and the mechanisms of pest suppression by anaerobic soil disinfestation are being further elucidated. Its integration with other non-fumigant approaches may also have promise. For example, a combination of anaerobic soil disinfestation and mustard seed meal application is currently being tested .Heat treatment with steam can be used for soil sterilization or pasteurization . Studies have shown that most plant pathogens, insects and weeds will die when moist soils are heated to temperatures higher than 150°F for 30 minutes . The duration and amount of steam needed to raise the soil temperature to 150°F depend on various soil factors, including texture, type and moisture content. Minuto et al. found that soil could be heated most rapidly at a moisture content between 8.5% and 12% in a sandy loam and between 6% and 7% in a sandy soil. Steam applied to field soil that raised the temperature to 158°F for 20 minutes resulted in weed control comparable to methyl bromide .

In addition to pest control, an advantage of steaming is that it lacks the negative environmental and worker health issues associated with chemical fumigants. Some have reported that steaming has little or no lasting negative impact on soil quality or soil microbial communities as opposed to the known potential impact of methyl bromide fumigation on both soil quality and microbes . Other studies have reported a more significant change in soil microbial activity due to steam sterilization . Differences among steam studies may be related to duration of steam application and soil temperatures attained during steam treatments as well as the soil organic matter content. Steam has also been shown to increase crop growth and yields . Previous work found that strawberry fruit yields from steam-treated soils were similar to those from soils fumigated with methyl bromide plus chloropicrin .Natural products such as mustard seed are being evaluated as bio-fumigants. Recent studies found that mustard seed meal amendment can suppress root infection by Rhizoctonia solani . We have been testing mustard seed meal in strawberry beds at rates of 500 to 4,000 pounds per acre incorporated into the soil. Mustard meal alone does not consistently produce high fruit yields or control weeds . One possible method to enhance solarization is to use combinations of mustard meal, chloropicrin, and metam sodium treatments . By heating the soil with solarization or steam, the pest control activity of metam sodium, chloropicrin or mustard meal may be higher than at ambient soil temperatures.A field study was conducted at Monterey Bay Academy from October 2010 to September 2011 to evaluate anaerobic soil disinfestation and steam with and without mustard seed meal application prior to planting strawberry beds.

Treatments included a control; Pic-Clor 60 at 300 pounds per acre as a standard; mustard seed meal at 3,000 pounds per acre; anaerobic soil disinfestation with rice bran at 9 tons per acre; anaerobic soil disinfestation with rice bran at 7.5 tons per acre and mustard seed meal at 3,000 pounds per acre; steam; and steam plus mustard seed meal at 3,000 pounds per acre. Trial design. The trial was arranged in a randomized complete block design with four replicates. Anaerobic soil disinfestation was initiated Oct. 7 to create a saturated condition. The plots were maintained above field capacity with intermittently applied irrigation water from Oct. 8 to Nov. 3, 2010. Steam was applied via spike injection from a stationary steam generator for a sufficient time to raise the soil temperature to 158˚F for 20 minutes on Oct. 13 and 14, 2010. Weed densities were measured in 25-square-foot sample areas covered with clear tarp, on Dec. 15, 2010, Jan. 21, Feb. 23 and April 6, 2011. Strawberry fruit was harvested weekly from April 28 to Sept. 15, 2011. Fruit was sorted as marketable and cull at each harvest date. Data were subjected to analysis of variance and means were separated using Fisher’s protected LSD. Trial results. Overall, the steam treatment and the steam treatment with mustard seed meal were as effective as Pic-Clor 60 in providing weed control . Anaerobic soil disinfestation plus rice bran suppressed weed densities, but it was less effective than Pic-Clor 60. No strawberry plant injury was observed in any of the treatments . Marketable yields data collected from April 28 to Sept. 15, 2011, indicate that strawberry fruit yields in the steam treatments and the anaerobic soil disinfestation treatments were comparable to those in the Pic-Clor 60 application . These data, along with data from our prior studies, show that steam is as effective as chemical fumigation; and that anaerobic soil disinfestation also produces yields equivalent to Pic-Clor 60 but may need to be combined with herbicide use in severely weed-infested sites. The costs of the anaerobic soil disinfestation treatments with rice bran, and with rice bran plus mustard seed meal, were $1,632 and $3,093 per acre, respectively, including material, spreading, incorporation and irrigation . The cost of steam was $10,440 per acre, compared to $1900 per acre for Pic-Clor 60. Therefore, although the yields and gross revenues were comparable across treatments, the net returns after treatment and harvest costs were highest for the Pic-Clor treatment, gutter berries followed by the anaerobic soil disinfestation with rice bran. The lowest net revenue was for the steam plus mustard seed meal treatments due to the high cost of the steam treatment. The cost data showed a critical need for more-efficient steam injection systems before steam can be adopted commercially. Recent advances with steam application equipment can reduce the cost of steam treatment to less than $5,500 per acre with the potential for further cost reductions . Since 2011 we have used an automatic mobile steam applicator in our research, which lowers the labor costs relative to those reported here by approximately 50% to 70%. It mixes steam with soil, allowing soil to be heated from 60˚F to 160˚F in 90 seconds — much more rapidly than the steam application system used here .The phase-out of methyl bromide has proven to be a daunting task for the California strawberry industry. Not only are strawberry producers faced with the likelihood that methyl bromide will no longer be available to them by 2015, but they also must deal with increasing regulatory stringency on the use of all soil fumigants. While fumigants face an uncertain future in California, barrier films can help trap fumigants in the soil and reduce the likelihood of environmental or health impacts associated with fumigants in the atmosphere.

It appears very likely in the near future that barrier films will be the only type of film approved for use with fumigants in California.Potential methods of strawberry production that do not use fumigants include growing plants in substrates and using steam treatments or anaerobic soil disinfestation. All of these systems are being evaluated on a much larger scale, from 1 to 10 acres, with different soil types, to determine commercial feasibility and cost effectiveness. It is not likely, nor is it desirable from a pest management perspective, that one non-fumigant system will dominate on a large percentage of the strawberry acreage. Multiple production systems, using fumigants and non-fumigants, would allow producers to rotate treatments to suppress soil pests.Grapevine berry ripening can be divided into three major stages. In stage 1, berry size increases sigmoidally. Stage 2 is known as a lag phase where there is no increase in berry size. Stage 3 is considered the ripening stage. Veraison is at the beginning of the ripening stage and is characterized by the initiation of color development, softening of the berry and rapid accumulation of the hexoses, glucose and fructose. Berry growth is sigmoidal in Stage 3 and the berries double in size. Many of the flavor compounds and volatile aromas are derived from the skin and synthesized at the end of this stage. Many grape flavor compounds are produced as glycosylated, cysteinylated and glutathionylated precursors and phenolics and many of the precursors of the flavor compounds are converted to various flavors by yeast during the fermentation process of wine. Nevertheless, there are distinct fruit flavors and aromas that are produced and can be tasted in the fruit, many of which are derived from terpenoids, fatty acids and amino acids. There are 69 putatively functional, 20 partial and 63 partial pseudogenes in the terpene synthase family that have been identified in the Pinot Noir reference genome. Terpene synthases are multi-functional enzymes using multiple substrates and producing multiple products. More than half of the putatively functional terpene synthases in the Pinot Noir reference genome have been functionally annotated experimentally and distinct differences have been found in some of these enzymes amongst three grape varieties: Pinot Noir, Cabernet Sauvignon and Gewürztraminer. Other aromatic compounds also contribute significant cultivar characteristics. C13-norisoprenoids are flavor compounds derived from carotenoids by the action of the carotenoid cleavage dioxygenase enzymes. Cabernet Sauvignon, Sauvignon Blanc and Cabernet Franc are characterized by specific volatile thiols and methoxypyrazines. Enzymes involved in the production of these aromas have been recently characterized. Phenolic compounds play a central role in the physical mouthfeel properties of red wine; recent work relates quality with tannin levels. While the grape genotype has a tremendous impact on tannin content, the environment also plays a very large role in grape composition. The pathway for phenolic biosynthesis is well known, but the mechanisms of environmental influence are poorly understood. Ultimately, there is an interaction between molecular genetics and the environment. Flavor is influenced by climate, topography and viticultural practices. For example, water deficit alters gene expression of enzymes involved in aroma biosynthesis in grapes, which is genotype dependent, and may lead to increased levels of compounds, such as terpenes and hexyl acetate, that contribute to fruity volatile aromas. The grapevine berry can be subdivided into the skin, pulp and seeds. The skin includes the outer epidermis and inner hypodermis . A thick waxy cuticle covers the epidermis. The hypodermal cells contain chloroplasts, which lose their chlorophyll at veraison and become modified plastids; they are the sites of terpenoid biosynthesis and carotenoid catabolism. Anthocyanins and tannins accumulate in the vacuoles of hypodermal cells. Pulp cells are the main contributors to the sugar and organic acid content of the berries.