Greenhouse studies have evaluated the impact of metam sodium applications, with and without solarization films and associated soil heating, on development of FOV symptoms in varieties of cotton previously recognized as highly-susceptible (a Pima, Phytogen 810-R or DP-744) or moderately susceptible (an Acala, Phytogen-72). The soil media used was a 1:2 mix of soil from a highly infested field site mixed with steam-treated potting mix. Trays of soil mix received the treatments and post-treatment, the soil was transferred into clean, waxed cardboard containers to plant out the seed for further evaluations of disease symptom development and plant survival percentages. In metam sodium trials, three different rates of metam sodium alone did not significantly impact the survival rate (about 30%) or symptoms (root vascular stain index rating averaging about 3 on a scale of 0 (no symptoms) to 5 (severe symptoms) in highlysusceptible Pima varieties. In the moderately susceptible Acala variety, the metam sodium treatments improved the survival rate and reduced vascular stain ratings wl1en compared with untreated soil. In the first trial, averages of about 90% survival were recorded for treated soil versus about 60% survival for untreated. In the second trial, an average of about 90% survival was recorded for treated soil versus…
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Changes in the California cotton industry enacted in 1998 allow for a much broader range of varieties to be grown in the SJV. It will be important for growers to have unbiased sources of varietal performance information that will answer some of the questions regarding yield performance, growth characteristics and quality of available varieties. These trials involving newly-available CA Upland varieties complement the combined SJV Cotton Board and the UCCE Farm Advisor Approved Acala studies. Trials include standard varieties of Acalas in order to have some more complete indices of varietal comparisons. The range of yield potential as well as the range of quality characteristics across the varieties now available will mean that growers have an even more difficult job than usual in balancing the combination of yield and quality (and resulting price)…
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Acala cotton varieties were grown on about 100,000 acres out of the greatly reduced total acreage of about 275,000 acres in 2008. Part of the reason for continuing changes in acreages is overall reductions in planted cotton acreage in California in recent years, but part is also related to shifts to Pima and non-Acala Upland cotton. There are tradeoffs in shifting to Pima (typically reductions in yields) and in shifts to non-Acala Uplands (typically lower price for lint), and growers need reliable, unbiased information regarding expected lint yields and fiber quality in order to make reasonable, lower-risk decisions. The San Joaquin Valley Cotton Board will remain the avenue for varieties to enter our “Approved Variety” testing program. Within Acala testing, the combined SJV Cotton Board and the UCCE Farm Advisor Approved Acala trials represents a source for broadly-based information on varietal performance. Separate trials involving newly-available CA Upland varieties continue to be conducted by Hutmacher and staff at Shafter and West Side REC sites to complement SJVCB I Approved Acala studies. Variety evaluations for yield and quality performance for…
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WELCOME
to the
UNIVERSITY OF CALIFORNIA
SHAFTER RESEARCH & EXTENSION CENTER
The information contained in this booklet was assembled for distribution at the 2006 Cotton Field Day at the Shafter Research & Extension Center. The following items are included for your information:
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Recently, water, energy, fertilizer, pesticides, labor cost and the capital investment in modem irrigation systems have risen dramatically and at a rate greater than farmer returns. Studies have demonstrated that drip irrigation can improve water use efficiency, reduce fertilizer losses and reduce application of pesticides and fungicides, particularly when compared with flood, furrow and sprinkler irrigation. As drip irrigation knowledge has evolved, Netafim Irrigation has developed Low Pressure Systems (LPS) that operate at 3 psi pressure while achieving a distribution uniformity of 90% or better. The conversion of leveled furrow irrigated fields to LPS using pressurized district water eliminates additional energy expenditures. It also conserves significant water and energy and allows the use of low pressure components, thus reducing the capital inputs of LPS. Three years of…
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Fusarium w.ilt of cotton in California has been considered a potentially serious fungal disease caused by the organism Fusarium oxysporum vas infectum (also called ”FOV”) for many decades in several areas of the San Joaquin Valley (SJV). In the past, however, damage associated with FOV in SJV cotton has been notable only in areas with the combination of: (a) moderate to high populations of one or more specific races of FOV (usually race 1 ); (b) soils with a sandy or sandy loam texture; and (c) where root lrnot nematodes were present in high-enough populations to cause some significant root damage. Past research generally indicated that FOV damage was worst when both FOV inoculum and nematodes were present in relatively high…
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Preventing sticky cotton is crucial in producing quality cotton. Late-season populations of cotton aphid and Silverleaf whitefly can produce significant amounts of honeydew when populations build. These pests are of most concern from mid-boll filling through harvest, when insect populations build and threaten exposed lint. Pest management guidelines for cotton aphid and silverleaf whitefly focus on strategies to use once threshold pest populations are reached, with the approach varying with the composition of the developing population (nymphs, adults), crop growth stage, and with the presence of exposed lint. Current pest management guidelines for whitefly and aphid can be interpreted as meaning defoliation is the final event of the season. This is based on the assumption…
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1998 was a year which brought many changes in the variety situation in the CA cotton industry. Many o f the management recommendations currently in place for CA Upland cotton are based upon years of research on varieties such as SJ-2, GC-510 and Maxxa. The introduction of some potentially widely-different varieties which were developed in environments outside of CA in most cases represents a real challenge in terms o f identifying the most suitable management practices for best results under SJV conditions. These “newly-available” varieties that will come into CA will have the name designation “CA Upland”…
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1998 Studies
The objectives of these studies with Pima are to evaluate approved varieties under different environmental conditions and management. The studies are part of a regional Beltwide Pima variety evaluation that includes Texas, New New Mexico, Arizona and California, and are supported in part through the California Crop Improvement Association. In addition to five grower fields, two UCCE Research Center test locations were used in the 1998 trials, the West Side and Shafter Research and Extension Centers of the University of California. The West Side location is in…
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