California Plant Research Articles

The new hot ticket [concentrating solar thermal power

A lack of government support pulled the rug from under the fledgling Concentrating Solar Thermal Power (CSP) industry. Concentrating Solar Thermal Power (CSP) industry has been striving for many years to achieve, despite a false dawn in the 1980s when CSP's early pioneer (Luz International, which built nine CSP plants in California's Mojave Desert) went bankrupt. This signalled the start of a dormant period as CSP technology gradually faded into the background of the renewable electricity sector, surpassed by robust interest in the more 'glamorous' technology of PV.

Finding a bright spot

The photovoltaic (PV) industry has been a steady bright spot through economic ups and downs, and the future is looking brighter than ever. PV deployment has grown rapidly - from 0.3 MW in the 1980s to an expected 3,000 MW by 2010. Fueled by technical, economic, environmental, and social drivers, the contribution of PV to the U.S. electricity supply mix will likely be several times that amount by 2020. PV power systems and the utility industry have had a 25-year courtship with many different types of engagement. Utilities participated in the first ground-mounted power plants and rooftop installations on residences, schools, airports, hospitals, and other public buildings. These projects included U.S. Department of Energy (DOE)-sponsored residential experiment stations in Maine, Florida, and New Mexico in the 1980s; early PV plants in California and throughout the Southwest; and grid connection, demonstrations, inverter and system testing, and related standards development. Electric service providers are well positioned to expand their engagement in deploying PV systems. Many have found themselves in a bright spot relative to solar business opportunities. However, most providers are still facing the decision of whether to modify traditional business models for active engagement or maintain a reactive stance relative to PV and grid integrations. In either case, R&D that will lead to a more flexible and interactive electric distribution system is needed. A near-term priority for individual utilities is to define the grid-interactive and grid-independent applications and markets that offer the greatest potential risks and rewards and to develop plans for addressing them. This is particularly important in areas with excellent solar resources, strong incentives,or both. And this may hold true across the country under current policy and market conditions.

Southern Highbush Blueberries are A New Host forScirtothrips citri(Thysanoptera: Thripidae) In California

Citrus thrips, Scirtothrips citri (Moulton), is a major pest for citrus growers in California (Flint et al. 1991; Morse 1995). Citrus thrips feed on the rind at the stem end of young citrus fruit causing a characteristic ring scar (Morse 1995; GraftonCardwell et al. 1998, 2003). They also feed on the new flush of citrus, causing twisting and abnormal growth (Grafton-Cardwell et al. 1998). Heavy infestations of citrus thrips cause new flush to die and drop from the plant (Grafton-Cardwell et al. 1998). Even though citrus thrips was first described based on the damage it caused on California citrus (Horton 1918), it was obviously present prior to the introduction of citrus in the region, i.e., it is native to California and northwestern Mexico and has been observed on over 50 host plants in California, in particular in association with plants that produce an aromatic oil (Morse 1995). Prior to 1992, highbush blueberries ( Vaccinium corymbosum L.) were not grown commercially in California due to the warm climate (Jimenez et al. 2005; Strik & Yarborough 2005). However, several southern highbush blueberry varieties were developed by crossing northern highbush blueberries with several other Vaccinium species (Jimenez et al. 2005; Strik & Yarborough 2005). Southern highbush blueberries require lower chill hours for bud break and are well adapted to California’s climate (Jimenez et al. 2005). As a consequence, California blueberry acreage dramatically increased after 1992 (Jimenez et al. 2005). In 2005, several growers reported widespread damage to the young foliage of their blueberries that appeared to be associated with thrips. Most of the damage was curling and abnormal growth of the new leaves as well as scarring of new twigs.

Tandom reverse osmosis process for zero-liquid discharge

Major sources of wastewater generated on land can benefit from, and often are in need of, processes for the complete recovery of water, having only solid by-products or waste for disposal. This applies to municipal and industrial wastewater and brackish water reverse osmosis (RO) plants and agricultural irrigation. High recovery of water with RO membranes is by far the most efficient method of processing waste and brackish water. Recoveries ranging from 70 to 90% are possible, limited by precipitation of insoluble salts and coagulation of colloidal particles. If emerging intermediate precipitative treatments of the limiting foulants can become widely successful, a tandom second RO step of similar recovery rates will reach an overall water recovery of 97–99%. The remaining 1–3% of the original water volume can be addressed with evaporative concentrators. Based on our initial successes, we clearly see this tandom RO process to be of universal utility. Precipitated salts from the treatment of the primary RO concentrate are mainly divalent cations (Ca, Mg, Sr, Ba) with coagulated silica and colloidal matter. Solutes that survive the secondary RO are mainly soluble monovalent cations (Na, K). The overall tandom RO process thus constitutes a way to fractionate divalent cation salts from the monovalent cation salts. Both salt fractions may find commercial use and not be entirely wasted. We currently are actively assisting municipal RO plants in California in maximizing the percent recovery in the primary ROs, and for the moment, minimizing the volumes of raw water needed and volumes of concentrate that have to be discharged. To illustrate the necessity of dealing with the unique water chemistry of each RO plant, we present the well water analyses of three municipal systems within a 25-mile radius of Riverside, CA. In each case, due to the high cost of discharging concentrate into a brine line to the sea, close to limiting primary RO recoveries have been reached. The results of autopsies and foulant analyses performed on membranes from these three plants identify the foulants that need to be precipitatively removed before treatment with secondary RO. Further work is being considered along these lines.

Designing a Zero Liquid Discharge Water Treatment Plant in California

Designing a Zero Liquid Discharge Water Treatment Plant in California

First Report of Angelonia flower break virus in Nemesia spp. and Other Ornamental Plants in California.

Between June 2006 and July 2007, ornamental plant samples were collected from four counties in California (Riverside, Sacramento, San Diego, and Santa Barbara) and tested for the presence of Angelonia flower break virus (AnFBV) using ELISA (Agdia, Inc., Elkhart, IN). Tissue samples were from propagation facilities or wholesale outlets except those from Riverside County, which were from retail stores. Thirteen positive samples were found in three varieties each of Angelonia and Nemesia spp. and seven varieties of Verbena spp., with at least one positive from each county. Foliar symptoms ranged from asymptomatic to a mild mosaic with distinct flower breaking in the Angelonia spp. Results were confirmed by reverse transcription (RT)-PCR of the coat protein gene (1) and the 1,172-bp amplicons were sequenced. Viral isolates from the three varieties of the Angelonia spp. had 98 to 99% nucleotide similarity and 99 to 100% amino acid identity to the Maryland strain of AnFBV (1; GenBank Accession No. DQ221212), with 91 to 92% nucleotide similarity and 96 to 97% amino acid identity to the Israel and Florida strains (GenBank Accession Nos. DQ223771 and DQ219415). All viral isolates from the Nemesia and Verbena spp. plants had nucleotide similarities of 96 to 98% and 98% amino acid identity to the Israel and Florida strains, with 91 to 92% nucleotide similarity to the Maryland strain. AnFBV has been previously reported in Angelonia and Verbena spp. among other hosts (1,2), but not in Nemesia spp. and not in California. This recently described carmovirus appears to be well established in the state in a variety of ornamental plant species.

Catalogue of Nonnative Vascular Plants Occurring Spontaneously in California Beyond Those Addressed in the Jepson Manual – Part II

ABSTRACT We present Part II of a catalogue documenting nonnative vascular plant taxa occurring spontaneously in California beyond those addressed in The Jepson Manual: Higher Plants of California (Hickman 1993). Here we document an additional 117 taxa occurring spontaneously in California that were not accounted for in Part I (Hrusa et al. 2002) or in The Jepson Manual. The catalogue was compiled from new collections by the authors and others, previously existing herbarium specimens, peer-reviewed publications, other printed reports, and direct communications with field botanists. Only reports backed by herbarium vouchers are accepted as adequately documented. Of the 117 taxa, 42 are fully or sparingly naturalized in relatively undisturbed wildland habitats, 14 are naturalized in non-wildlands (roadsides, fallow fields, croplands, other disturbed areas), 13 are tenuously established or locally persisting, 22 are weeds of greenhouse or other horticultural environments, 7 are presumed to be non-persisting c...

Bronchiolitis obliterans in workers exposed to flavoring chemicals

Medical and environmental surveys at microwave popcorn plants and flavoring production plants have revealed a risk for bronchiolitis obliterans in workers exposed to flavoring chemicals. Workers in other food industries may also be at risk. This review summarizes the available information on disease characteristics and natural history and provides information on workplace characteristics associated with disease development. Investigations carried out in flavoring plants in California have identified severely affected current and former workers in four plants. Affected former workers have also been identified at a plant in the Netherlands that manufactured diacetyl, a predominant chemical in butter flavorings which has been implicated as a causal agent for lung disease in microwave popcorn workers. Workers who manufacture or use flavorings can be subjected to repeated intense exposures to flavoring chemicals. Affected workers can progress to severe fixed airways obstruction in as little as 7 months. Since medical treatment is generally ineffective, early identification of affected workers and removal from further exposure, along with control of exposures to protect coworkers, are essential to minimize this hazard.

Outcomes of the California ban on pharmaceutical lindane: clinical and ecologic impacts.

IntroductionThere are increasing concerns over the presence and implications of pharmaceutical agents in water. In 2002, California banned pharmaceutical use of lindane because of concerns about water quality, as lindane treatment for head lice and scabies was found to be a significant factor adversely affecting wastewater quality.ObjectivesIn this article we describe the effects the ban has had on wastewater quality, unintentional exposures, and clinical practice. This is the first time that a pharmaceutical has been outlawed to protect water quality. As such, this ban provides a rare opportunity to evaluate the possible or potential outcomes of future public health interventions aimed at reducing pharmaceutical water contamination.MethodsWe compiled data on lindane in wastewater treatment plant effluent for several large plants in California and one outside of California. Data on exposures to lindane were obtained from records of the California Poison Control System. We assessed the impact on clinical practice via a survey of 400 pediatriciansResultsWastewater treatment plant monitoring showed that lindane declined in California after the ban. Similarly, unintentional exposure calls declined. Most physicians were aware of the ban (81%) and had used lindane previously (61%), but they did not notice any difficulties with the ban (78%).ConclusionsThe California experience suggests that elimination of pharmaceutical lindane produced environmental benefits, was associated with a reduction in reported unintentional exposures, and did not adversely affect head lice and scabies treatment. This ban serves as a model for governing bodies considering limits on the use of lindane or other pharmaceuticals.

Sewage and community shower drains are environmental reservoirs of Fusarium solani species complex group 1, a human and plant pathogen

In two recent studies, clinical isolates in the Fusarium solani species complex (FSSC) were sequenced; one of the most common lineages was FSSC Group 1 (FSSC 1), a phylogenetic species that is synonymous with F. solani f. sp. cucurbitae race 2, a pathogen of cucurbit fruits. FSSC 1 was also identified in sink and shower drains in two hospitals. The environmental sources of FSSC 1 are important for understanding the epidemiology of both human and plant diseases caused by this organism. FSSC 1 was detected in sewage influent at all six tested urban wastewater treatment plants (WWTPs) in California with a concentration ranging from 75 to 413 colony-forming units (cfu) l(-1), a mean of 246 +/- 52 cfu l(-1) and a median of 254 cfu l(-1). During the treatment process, the concentration of FSSC 1 in the solid and liquid fractions diminished. FSSC 1 was detected in five and six of 14 community shower drains by culturing and polymerase chain reaction, respectively, whereas FSSC DNA was detected in all drains. FSSC accounted for 17 +/- 6% (n = 14) of the total fungal DNA in the drains. FSSC 1 was rarely isolated from post-harvest cucurbit fruits and was not found in cucurbit fields in California.

Managing Renewable Energy Sales at a Wastewater Treatment Plant in California

Managing Renewable Energy Sales at a Wastewater Treatment Plant in California

Cavitation resistance and seasonal hydraulics differ among three arid Californian plant communities

Vulnerability to water stress-induced cavitation was measured on 27 woody shrub species from three arid plant communities including chaparral, coastal sage and Mojave Desert scrub. Dry season native embolism and pre-dawn water potential, and both wet and dry season xylem specific hydraulic conductivity (Ks) were measured. Cavitation resistance, estimated as water potential at 50% loss in conductivity (Psi50), was measured on all species during the wet season and on a subset of species during the dry season. Cavitation resistance varied with sampling season, with 8 of 13 sampled species displaying significant seasonal shifts. Native embolism and water potential were useful in identification of species displaying seasonal shifts. The Ks was not different among sites or seasons. The Psi50 varied among species and communities. Within communities, interspecific variation may be partially explained by differences in rooting depth or leaf habit (evergreen, semi-deciduous, deciduous). Communities diverged in their Psi50 with chaparral species displaying the greatest cavitation resistance regardless of sampling season. The greater cavitation resistance of chaparral species is surprising, considering the greater aridity of the Mojave Desert site. Adaptation to arid environments is due to many plant traits, and aridity does not necessarily lead to convergence in cavitation resistance.

Intake-to-delivered-energy ratios for central station and distributed electricity generation in California

In previous work, we showed that the intake fraction (iF) for nonreactive primary air pollutants was 20 times higher in central tendency for small-scale, urban-sited distributed electricity generation (DG) sources than for large-scale, central station (CS) power plants in California [Heath, G.A., Granvold, P.W., Hoats, A.S., Nazaroff, W.W., 2006. Intake fraction assessment of the air pollutant exposure implications of a shift toward distributed electricity generation. Atmospheric Environment 40, 7164–7177]. The present paper builds on that study, exploring pollutant- and technology-specific aspects of population inhalation exposure from electricity generation. We compare California's existing CS-based system to one that is more reliant on DG units sited in urban areas. We use Gaussian plume modeling and a GIS-based exposure analysis to assess 25 existing CSs and 11 DG sources hypothetically located in the downtowns of California's most populous cities. We consider population intake of three pollutants—PM 2.5, NO x and formaldehyde—directly emitted by five DG technologies—natural gas (NG)-fired turbines, NG internal combustion engines (ICE), NG microturbines, diesel ICEs, and fuel cells with on-site NG reformers. We also consider intake of these pollutants from existing CS facilities, most of which use large NG turbines, as well as from hypothetical facilities located at these same sites but meeting California's best-available control technology standards. After systematically exploring the sensitivity of iF to pollutant decay rate, the iFs for each of the three pollutants for all DG and CS cases are estimated. To efficiently compare the pollutant- and technology-specific exposure potential on an appropriate common basis, a new metric is introduced and evaluated: the intake-to-delivered-energy ratio (IDER). The IDER expresses the mass of pollutant inhaled by an exposed population owing to emissions from an electricity generation unit per quantity of electric energy delivered to the place of use. We find that the central tendency of IDER is much greater for almost every DG technology evaluated than for existing CS facilities in California.

First Report of Tomato yellow leaf curl virus Associated with Tomato Yellow Leaf Curl Disease in California.

Tomato yellow leaf curl disease caused by the whitefly-transmitted begomovirus (genus Begomovirus, family Geminiviridae) Tomato yellow leaf curl virus (TYLCV) is one of the most damaging diseases of tomato. TYLCV was introduced into the New World in the early 1990s and by the late 1990s, it was found in Florida (2). In 2005 and 2006, the virus was reported from northern Mexico (states of Sinaloa and Tamaulipas) (1) and subsequently from Texas and Arizona. In March 2007, tomato (Lycopersicon esculentum) plants growing in a greenhouse in Brawley, CA showed TYLCV-like symptoms including stunted upright growth, shortened internodes, and small upcurled leaves with crumpling and strong interveinal and marginal chlorosis. These plants also sustained high populations of whiteflies. Symptomatic tomato leaves and associated whiteflies were collected from inside the greenhouse. Leaf samples also were collected from symptomless weeds (cheeseweed [Malva parviflora] and dandelion [Taraxacum officinale]) outside of the greenhouse. Total nucleic acids were extracted from 41 symptomatic tomato leaf samples, seven samples of adult whiteflies (approximately 50 per sample), and six leaf samples each from cheeseweed and dandelion. PCR analyses were performed with the degenerate begomovirus primers PAL1v1978 and PAR1c496 (3) and a TYLCV capsid protein (CP) primer pair (4). The expected size of approximately 1.4-kbp and 300-bp DNA fragments, respectively, were amplified from extracts of all 41 symptomatic tomato leaves and adult whitefly samples; whereas the 300-bp DNA fragment was amplified from all six cheeseweed samples and four of the six dandelion samples. Sequence analysis of a portion of the AC1/C1 gene from the approximately 1.4-kbp fragment amplified from 12 tomato leaf samples and four whiteflies samples revealed 99 to 100% identity with the homologous sequence of TYLCV from Israel (GenBank Accession No. X15656). The putative genome of the California TYLCV isolate was amplified using PCR and an overlapping primer pair (TYBamHIv: 5'-GGATCCACTTCTAAATGAATTTCCTG-3' and TYBamHI2c: 5'-GGATCCCACATAGTGCAAGACAAAC-3'), cloned and sequenced. The viral genome was 2,781 nt (GenBank Accession No. EF539831), and sequence analysis confirmed it was a bona fide isolate of TYLCV. The California TYLCV sequence is virtually identical (99.7% total nucleotide and 100% CP amino acid sequence identity) to a TYLCV isolate from Sinaloa, Mexico (GenBank Accession No. EF523478) and closely related to isolates from China (AM282874), Cuba (AJ223505), Dominican Republic (AF024715), Egypt (AY594174), Florida (AY530931), Japan (AB192966), and Mexico (DQ631892) (sequence identities of 98.2 to 99.7%). Together, these results establish that TYLCV was introduced to California, probably from Mexico. Because the tomatoes in this greenhouse were grown from seed, and symptoms did not appear until after initial fruit set, the virus was probably introduced via viruliferous whiteflies. To our knowledge, this is the first report of TYLCV infecting tomato plants in California.

California Plant to Produce Fuel From Biosolids

This article announces the construction of a full‐scale SlurryCarb? facility by EnerTech Environmental Inc. of Atlanta, Georgia. The facility will be located in Rialto, California, and HDR Design‐Build Inc. was chosen as the construction company. EnerTech's patented SlurryCarb process economically produces a renewable fuel, called E‐Fuel?, from biosolids and other high‐moisture wastes.

First Report of Leaf Spot and Twig Blight of Rhododendron spp. Caused by Phytophthora hibernalis in Spain.

During the early spring of 2004, an estimated 20% of containerized nursery stocks of Rhododendron spp. in Asturias (northern Spain) were affected by a foliar disease that has reoccurred annually. Leaf spots were dark brown to almost black, generally oval to round, visible from both sides of the leaf, and expanded to affect the entire leaf including the petiole. Affected leaves abscised from the plant. A Phytophthora sp. was consistently isolated from symptomatic leaf tissues on PARBH medium (3) and hyphal tips were transferred onto potato dextrose agar (PDA). Colonies grown on PDA at 20°C were submerged, had a growth rate of 2.2 mm/day, and had lobes of compact mycelium. Sporangia were semipapillate and caducous with a pedicel (20.0-) 37.7 (-52.5) μm long. Sporangia were asymmetrical in shape with the broadest point near the apex: 25.2 to 40.4 μm long × 10.2 to 15.8 μm wide (average 33.1 × 12.6 μm), and length/width ratio was 2.8:1. Chlamydospores were not observed. Isolates were homothallic and oogonia ranged from 26.5 to 27.5 μm in diameter. Antheridia were mostly amphigynous but occasionally paragynous. Oospores were plerotic and 23.1 to 25.5 μm in diameter. These characteristics conformed to those of Phytophthora hibernalis Carne (2). Sequences of the internal transcribed spacer regions on the isolates and comparison with other sequences in GenBank showed that they were identical to P. hibernalis (Accession No. AY827556.1 from Citrus sp.). For pathogenicity tests, four isolates of P. hibernalis were used to inoculate detached leaves of Rhododendron hybrid Brigitte. The underside of five detached leaves was inoculated with a drop of 40 μL of a suspension of 104 zoospores/ml. Controls were inoculated with a 40-μL drop of sterile distilled water. Leaves were incubated in a moist chamber at 20°C in the dark. A quantification of the lesion area was made 8 days after inoculation using the software Assess-APS. All inoculated leaves developed necrotic lesions that ranged from 0.246 to 1.512 cm2. P. hibernalis was reisolated from infected tissue. Symptoms were not detected on the controls. The test was repeated twice and similar results were obtained each time. P. hibernalis has been described previously as causing brown rot on citrus in Spain (4) and was isolated from rhododendron plants in California and Oregon (1). To our knowledge, this is the first record of P. hibernalis causing foliar blight on Rhododendron species in Spain as well as in Europe.

Colloidal fouling of RO membranes following MF/UF in the reclamation of municipal wastewater

Major municipal wastewater reclamation plants in California, USA, Singapore, and many built or planned for other regions of the world use the high pathogen reduction properties of microfiltration/ultrafiltration (MF/UF) membranes followed by reverse osmosis (RO) membranes. Operational experiences in these plants suggest that while MF and UF membranes encounter pore and cake fouling by colloidal particles (0.1 micron down to molecular sizes, ie. nanoparticles), a significant fraction of the smaller colloidal particles pass through the MF and UF membranes, and end up on RO membranes as cake-layer foulants. Autopsies, foulant analyses and cleaning studies performed on fouled RO membranes from the plants and pilot plants showed that colloidal natural organic matter, colloidal calcium phosphate and some times colloidal silicates are the main components. These colloidal particles have great affinity towards aggregation with each other. Due to incomplete removal by MF and even UF, fouling of RO membranes downstream becomes measurable by trend-charts of normalized values of permeate flow, differential pressure and salt passage. Normalized permeate flow is the most sensitive, and an early indicator of such fouling. In this paper we will provide some details of our studies and provide literature evidences that support the conclusion that calcium phosphate in foulants originated as nanoparticles in the wastewater.

Introduction to California soils and plants: serpentine, vernal pools, and other geobotanical wonders

Introduction to California soils and plants: serpentine, vernal pools, and other geobotanical wonders

Water treatment: Reducing backwash with air scouring

An old filtration system at a water treatment plant in California suffered from blocked filter media, which significantly reduced effluent water quality. Air scour technology from Roberts Filter Group, new to the UK, reduced backwash by 50%.

Energy Efficiency, Exposure, and Disease Burden: The Health Benefits of Adding Insulation to California Homes?

TAA1-O-04 Introduction: In 2004, more than 62 gigawatts (GW) of installed generating capacity produced electric energy for consumption in California. We apply here methods of life-cycle assessment to assess for the California region how increasing energy efficiency from installing residential insulation impacts the population exposures to air pollutants and the associated disease burden. For both the current mix of electrical energy producing technologies and for insulation manufacturing, we consider locations, emissions, and disease burdens associated with insulating new and existing residences. Methods: We focus on NOx, SO2, PM2.5, BaP, benzene, and naphthalene emissions from electricity generating plants in California. We characterize exposure separately for rural and urban environments using methods in the U.S. Environmental Agency's Tool for the Reduction and Assessment of Chemicals and other environmental Impacts (TRACI). TRACI uses the CalTOX model to estimate exposures and quantifies disease burdens with human damage factors (HDFs). HDFs are expressed in disability adjusted life years (DALYs) per kilogram pollutant emitted. As a case study, we quantify changes in emissions and disease burden from installation of fibreglass attic insulation in the nearly 3 million electricity-heated homes throughout California. We compare these estimates with those from the insulation manufacturing. Results: In urban regions of California, we estimate typical individual intake fractions (iFi) from power plant emissions on the order of 10−13 (10−14 for BaP), and lower but within the same order of magnitude in rural regions. HDFs are dominated by PM2.5 exposures whose HDFs are at least 2 orders of magnitude greater than HDFs of the other chemicals. NOx and SO2 have the lowest HDFs. Upgrading existing residential insulation to DOE recommended levels eliminates, over the estimated 30-year lifetime of the insulation, approximately 50 DALYs from power-plant emissions per million metric ton (MMT) of insulation installed, mostly from the elimination of PM2.5 emissions. In comparison, we estimate that the manufacture of this insulation results in DALYs per MMT comparable to or even greater than those avoided. Discussion and Conclusions: Our case study results reflect the relatively low baseline disease burden associated with electricity generation in California. This is due in large part to the majority use of natural gas for electricity production. Because existing methods for fibreglass manufacturing are quite high in particle-generation, PM2.5 emissions account for nearly 99% of the DALYs associated with it. Other insulation material, such as cellulose, may result in significantly lower disease burdens.