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Understanding the changes in early growth efficiency (GE, growth/leaf area) may improve forest production through the selection of appropriate genotypes at early stages. We investigated different early growth responses of genotypes of Eucalyptus globulus (7), E. nitens (3), and E. nitens × E globulus (E. gloni) (7) in south-central Chile. To evaluate seasonal growth, plants of each genotype were established in a completely randomized block design in coarse sandy soil (i.e., low water holding capacity), with spring and summer irrigation. The current monthly increment (CMI) in wood volume (cm3 tree−1 month−1), and leaf area index (LAI, m2 m−2) were used to calculate GE at 4.1, 7.5, 10.4, 13.4, and 15.4 months of age, corresponding to five growing seasons (first summer, fall, winter, spring, and second summer). The interaction between genotype and season had a significant effect (p

Objectives, to stablish the frequency of BRCA1/2 mutation rate in high-penetrance breast cancer susceptibility population Methods Based on NCCN guidelines for testing criteria for high-penetrance breast cancer susceptibility genes genetic counseling was offered to 140 breast cancer patients in the hemato-oncology unit of Roosevelt Hospital at Guatemala City performing test with NGS and MLPA technology from 2019 to 2021. Results The overall BRCA1/2 mutation rate high-risk patients were 23% (33/140). Of the patients with mutations, 66.6% (22/33) had BRCA1 mutation, 33.3% (11/33) had BRCA2 mutation, of the mutated population the median age was 45 years. Regarding the phenotype in the mutated population, 75% were triple negative, 16% luminal and 9% with Her2 overexpression. Of the patients carrying the BRCA1 mutation, we identified the c.212+1G>A mutation in 40% of the patients, possibly a founder mutation. In the triple negative population and under 45 years of age, the percentage of patients with BRCA 1/2 mutation is 40.9 (88.8% BRCA1 and 11.1% BRCA2). Conclusions: we found a percentage of BRCA 1/2 mutations in the selected population (NCCN criteria) similar to that reported in other Latin American countries, highlighting the high percentage of BRCA mutations in women under 45 years with triple negative phenotype, previous reports have highlighted the frequency of the c.212+1G>A mutation of BRCA1 in breats cancer patient in Guatemala, in this study 40% of the BRCA1 mutations correspond to said mutation, considering it as a probable founder mutation. Citation Format: Juan Alvarado-Muñoz, Agatha Reyes-Morales, Marco Chivalan, Silvana Torselli, Hector Valenzuela, Gozalo Yalibat, Mario Ordoñez, Rosa León, Egly Alvarez. BRCA1/2 gene mutations in patients with high-risk breast cancer in a tertiary-level hospital in Guatemala [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr P5-03-17.

Simple Summary The thymus is the immune organ producing T lymphocytes that are essential to create immunity after encountering pathogens or vaccination. This review summarizes the thymus localization and histological studies, cell composition, and function in teleost fishes. We also describe how seasonal changes, photoperiod, water temperature fluctuations, and hormones can affect thymus development in fish species. Overall, the information helps identify future studies needed to understand thymus function in fish species and the immune system’s evolutionary origins. Since fish are exposed to pathogens, especially under aquaculture conditions, knowledge about the fish thymus and T lymphocyte can also help improve fish farming protocols, considering intrinsic and environmental conditions that can contribute to achieving the best vaccine responsiveness for disease resistance. Abstract The thymus in vertebrates plays a critical role in producing functionally competent T-lymphocytes. Phylogenetically, the thymus emerges early during evolution in jawed cartilaginous fish, and it is usually a bilateral organ placed subcutaneously at the dorsal commissure of the operculum. In this review, we summarize the current understanding of the thymus localization, histology studies, cell composition, and function in teleost fishes. Furthermore, we consider environmental factors that affect thymus development, such as seasonal changes, photoperiod, water temperature fluctuations and hormones. Further analysis of the thymus cell distribution and function will help us understand how key stages for developing functional T cells occur in fish, and how thymus dynamics can be modulated by external factors like photoperiod. Overall, the information presented here helps identify the knowledge gaps and future steps needed for a better understanding of the immunobiology of fish thymus.

Calibration of sap flux density equations for Eucalytus is required when using sapflow thermal dissipation probes to avoid large underestimations of transpiration and water use. Eucalyptus plantations are expanding in response to global wood demand but are raising concerns about their impacts on water supplies. Sustainable plantation management in areas with water conflicts will require accurate assessments of tree and stand water use. Thermal dissipation probes have been used to estimate tree water use, but recent work suggests that species-specific calibrations may be required to obtain accurate results. In this study, we quantified sap flux density (SFD) in 2-year-old Eucalyptus globulus Labill (Eg) and E. nitens × globulus (Eng) species using the thermal dissipation method developed by Granier. For each species we compared the original Granier equation with species-specific calibrations using whole tree potometers over a 36-h period. Our results showed that on average, Granier’s original equation significantly underestimated SFD in both species, and when scaled to the stand level, tree transpiration (Ec) was significantly lower compared to onsite calibrations. The Granier method also underestimated nocturnal transpiration for both genotypes. Measured calibration coefficients were similar and not statistically different between Eg and Eng. These results highlight the importance of species-specific calibrations using thermal dissipation probes for Eucalyptus species to improve stand water use estimates and inferences about ecological impacts.

Predicting Eucalyptus plantation productivity in the face of climate change is a key challenge for intensively managed forest plantations around the world. Forest industry tree improvement and advanced silvicultural programs are charged with maximizing forest production but face challenging selection choices where Eucalyptus genotypes may be sensitive to genetic × environment interactions (GxE). Our study investigated the importance of GXE interactions by measuring the early (establishment to 2.6 years old) cumulative growth response of 30 selected genotypes of Eucalyptus globulus, E. nitens, E. badjensis, E. smithii, E. nitens × globulus and E. camaldulensis × globulus hybrid seedlings established across contrasting water availability conditions (High vs Low Irrigation). We compared the same genotypes at a low vapor pressure deficit (VPD) and clayey soil (North site) and a high VPD sandy soil (South site) in order to evaluate the stability of these genotypes across environmental gradients and thus evaluate the importance of genetic versus environmental impacts on growth. Stand growth was evaluated at 2.6 years when leaf area index (LAI) reached canopy closure in order to estimate a growth efficiency relationship (GE) with current annual increment (CAI). As expected, irrigation increased cumulative growth and LAI for all taxas, except for E. smithii at the North site. Genotypes showed large significant differences of performance within and across sites under each irrigation treatment. However, a strong relationship between North and South cumulative volume at age 2.6 years was observed for irrigated genotypes but not for non-irrigated genotypes. This suggests that a large GxE interaction may be expected under low water resource availability conditions associated with strong effects in ranking change of evaluated taxas and genotypes. Comparing taxas with at least two genotypes or more in our experiment, GE increased under High Irrigation for all taxas across sites. However, E. nitens × globulus hybrids showed small differences between High vs Low Irrigation treatments GE relationships compared to E. nitens and E. globulus genotypes. Our results suggest the need for strategic allocation of genotypes to contrasting drought risk environments and the need to assess our understanding of how particular genotypes interact with water stress conditions.

The impact of potential future climate change scenarios on the irrigation water requirements (IRRs) of two major agricultural crops (coffee and seed corn) in Hawai'i was studied using the Irrigation Management System (IManSys) model. In addition to IRRs calculations, IManSys calculates runoff, deep percolation, canopy interception, and effective rainfall based on plant growth parameters, site specific soil hydrological properties, irrigation system efficiency, and long-term daily weather data. Irrigation water requirements of two crops were simulated using historical climate data and different levels of atmospheric CO2 (330, 550, 710 and 970 ppm), temperature (+1.1 and +6.4 °C) and precipitation (±5, ±10 and ±20%) chosen based on the Intergovernmental Panel on Climate Change (IPCC) AR4 projections under reference, B1, A1B1 and A1F1 emission scenarios. IRRs decreased as CO2 emission increased. The average percentage decrease in IRRs for seed corn is higher than that of coffee. However, runoff, rain canopy interception, and deep percolation below the root zone increased as precipitation increased. Canopy interception and drainage increased with increased CO2 emission. Evapotranspiration responded positively to air temperature rise, and as a result, IRRs increased as well. Further studies using crop models will predict crop yield responses to these different irrigation scenarios.

Soil moisture and organic matter level affects soil respiration and microbial activities, which in turn impact greenhouse gas (GHG) emissions. This study was conducted to evaluate the effect of irrigation levels (75% [deficit], 100% [full], and 125% [excess] of reference crop evapotranspiration requirements), and organic amendments (OA) type (chicken manure [CM] and bone meal [BM]) and OA application rates (0,168, 336 and 672 kg total N ha−1) on (i) soil physical properties (bulk density, organic matter content and soil moisture content) and (ii) soil carbon dioxide (CO2) emissions from a highly weathered tropical Hawai'ian soil. Carbon dioxide readings were consistently taken once or twice a week for the duration of the cropping season. A drip irrigation system was used to apply the appropriate amount of irrigation water to the treatment plots. Treatments were randomly selected and corresponding organic amendments were manually incorporated into the soil. Plots were cultivated with sweet corn (Ze...

Pseudoaneurysm of the left ventricle is rare and may occur as a result of transmural myocardial infarction. The course of rupture after acute myocardial infarction varies from a catastrophic event, with an acute tear leading to immediate death (acute rupture), or slow and incomplete tear leading to a late rupture (subacute rupture). Incomplete rupture may occur when the thrombus and haematoma together with the pericardium seal the rupture of the left ventricle and may develop into a pseudoaneurysm. Early diagnosis and treatment is essential in this condition. Two-dimensional color Doppler echocardiography is the first-choice method for most patients with suspected left ventricular pseudoaneurysm (LVP) and suggests left ventricular rupture in 85% to 90% of patients. We report the case of an 87-year-old woman presenting with symptoms and findings of myocardial infarction and left ventricular free wall rupture with a pseudoaneurysm formation diagnosed by echocardiography and confirmed on CT, MRI, and NM. She received only intense medical treatment, because she refused surgery with a favorable outcome. After 24-month followup, she is in NYHA functional class II. The survival of this patient is due to the contained pseudoaneurysm by dense pericardial adhesions, related to her previous coronary bypass surgery.

This study determined carbon dioxide (CO2) emissions from a tropical soil amended with organic compost (CP), chicken manure (CM), and untreated controls during three growing seasons of sweet corn (Zea mays L.). The organic amendments resulted in significantly greater CO2 emissions compared with control treatments. The time duration after organic amendment applications significantly affected CO2 emissions, especially during the warmer growing seasons. The cumulative soil CO2 emissions increased in the order of control < CP < CM probably due to a greater microbial activity and to the greater above and below ground biomass production from N fertilization of organic amendments.

Location-based services require to process and infer knowledge based on the understanding of people daily activities. This information acquires relevance in cases when elder people live alone since it could be used to infer facts about his/her health. In this paper a platform for getting location and activity data for indoors is presented. Gathered information is processed, first, to locate people at room level and then to identify whether a person is sitting, standing, walking or even running. For classification purposes we used an artificial neural network, which report an accuracy as high as 97.75 %. A web page, which complements the platform, is made available for those persons who want to know about the rate of visits to the rooms and the rate of, for instance, walking exercise. In our next version we would like to extend the identification of activity by detecting the way the inhabitant interacts with artifacts.

Efficient water resource management is one of the most important policy issues facing agriculture in Hawaii in the years ahead. Soil water sensors, multisensor capacitance probes (MCP), have been successfully used for different water management projects. These MCPs monitor water content at multiple depths and at various locations in real-time. The objectives of this study were to determine the effect of water content on field soil bulk density of Wahiawa silty clay tropical soil; measure field saturated hydraulic conductivity of this tropical soil; calibrate MCP system for this soil; and monitor and evaluate real-time soil water content variations under a tomato crop using the calibrated MCP system. Sensor calibration was conducted under laboratory conditions. Soil bulk density at different water contents and saturated hydraulic conductivity were measured on the field. Bulk density increased with increasing water content; there was a 30 percent bulk density increase as a result of 0.25 cm 3 cm -3 water content variation. Compared with the manufacturer's calibration, site specific laboratory calibration of MCP gave a more accurate determination of soil water. Field determined saturated hydraulic conductivity was higher than laboratory determined values reported in the literature for the same soil type. Real-time soil water content monitoring within the root zone showed substantial variations due to water input (irrigation and rainfall) and water output (evapotranspiration and deep percolations). However, water content variations were much further reduced in the soil layer below the root zone.

The use of living mulches to reduce the density of silverleaf whitefly, Bemisia argentifolii Bellows and Perring, and melon aphid, Aphis gossypii Glover, and the conveyances of aphid-transmitted virus, papaya ringspot virus-watermelon strain (PRSV-W), and squash silverleaf disorder on zucchini, Cucurbita pepo L. was evaluated during 1995 and 1996 in Oahu, Hawaii. Living mulches used were buckwheat ( Fagopyrum esculentum Moench) and yellow mustard ( Sinapis alba L.). Mean densities of aphids were significantly lower in zucchini grown with living mulch both years of the study. In contrast, whiteflies were lower only during the second year. The severity of squash silverleaf disorder was significantly higher in bareground zucchini compared with living mulch-diversified zucchini during both experiments. The percentage of zucchini plants displaying PRSV-W during the early season was significantly lower on zucchini grown in living mulches during both years of the study. The delay in PRSV-W in living mulch resulted in a higher percentage of fruits by weight displaying viral symptoms in bareground zucchini. Reductions in pest activities in living mulch-diversified zucchini resulted in higher marketable yields only during one year of the study.

The objective of this study was to determine if trap crops of Indian mustard, Brassica juncea (L.) Czern., and ‘Tastie’ head cabbage, Brassica oleracea variety capitata L., grown alongside a main crop of ‘Scorpio’ head cabbage would significantly reduce lepidopteran pest numbers and improve yields on the main crop. For the 2 most economically important lepidopteran pests in the trials, diamondback moth, Plutella xylostella (L.), and imported cabbageworm, Pieris rapae (L.), significantly higher numbers were found on trap-cropped Scorpio than on monoculture Scorpio for certain key sampling dates. Numbers of Plutella xylostella were higher on the trap crops than on trap-cropped Scorpio for certain key dates. It appears that Indian mustard and Tastie cabbage acted effectively as attractants, but through an undetermined mechanism contamination of the adjacent Scorpio crop occurred. There were no significant differences in yield or marketability between monoculture Scorpio and trap-cropped Scorpio. Various changes in agroecosystem management might allow the attractiveness of the trap crops to be used in a beneficial manner. Indian mustard and Tastie cabbage show potential for use as trap crops for Hellula undalis (F.), cabbage looper, Trichoplusia ni (Hubner), and green garden looper, Chrysodeixis eriosoma (Doubleday). An understanding of the mechanisms that explain the movement of Lepidoptera within vegetationally diverse agroecosystems would be useful for on-farm implementation of this technique. Problems inherent in field experiments that compare the effects of different cropping systems on mobile insect populations are also discussed.

Considerable controversy continues to exist in scientific and policy circles about how to tackle issues of global hunger, malnutrition, and rural economic decline, as well as environmental issues, such as biodiversity loss and climate change adaptation. On the one hand, powerful vested interests, with close ties to government, media, and academic institutions, propose high-input technology-based solutions, speculative and neoliberal “market-based” solutions, and export-oriented agricultural models. On the other hand, an international scientific and grassroots Food Movement has emerged, calling for a redesign of the Global Food System in support of small-scale agroecological farming systems. A call to re-evaluate our current Food Systems was made in 2008 by the International Assessment of Agricultural Knowledge, Science and Technology for Development (IAASTD). Here, using the IAASTD study as a backdrop, we review the recent literature to outline key contentious points in the controversy between the need for high-input and “techno-based” versus agroecological farming models. A critical assessment is made of proposed strategies to protect soil resources, improve nutrient and energy cycles, protect agrobiodiversity, and promote social well-being in rural communities. With an increase in the number of affluent consumers (i.e., the middle class) in the developing world, and with the continued problem of extreme and chronic poverty with other larger sectors of society, Organic Farming and Agroecology models are put forward as a sound social, scientific, and rural development strategy.

The important tropical root and tuberous crops cassava (Manihot esculenta), sweet potato (Ipomoea batatas), yams (Dioscorea spp.), and the aroids (especially Xanthosoma and Colocasia spp.) represent an important source of relatively inexpensive carbohydrates to large sectors of the population in tropical areas. One or more tropical root crops are normally a staple in rural communities and are typically grown on small-scale subsistence farms. The current status of the agroecology research on these crops, including productivity under polyculture systems, resource (water, nutrients, light, space) utilization, tolerance to environmental stress, pest dynamics response to habitat manipulation, and alternative cultural practices, is reviewed in this paper as they relate to the performance of these crops in small-scale tropical agricultural systems. The development of technological recommendations to improve the productivity of tropical root crops in the tropics is dependent on an understanding of import...

Cocoyam was grown in 100%, 50%, or 30% daylight to determine the effect of light intensity on growth characteristics at various stages of plant development. Beginning ≈ 2 months after planting, growth was monitored at three or four monthly intervals. Plants grown in shade had more petiole and leaf lamina growth and extension, as well as increased top : corm plus cormel ratio (dry-weight basis), than plants grown in 100% daylight. Shade-grown plants had a higher leaf area index and specific leaf area than sun-grown plants. Sun-grown plants had a higher net assimilation rate and specific leaf density than shade-grown plants. Linear equations were developed to predict lamina area through measurements of leaf lamina width and length, petiole length, and lamina dry weight. Cocoyam is an herbaceous, perennial, tropical herb grown for its edible starch-filled corms and cormels. The rhizome-like cormels, the part most often consumed, arise from the base of the corm below the soil surface (0'Hair and Asokan, 1986). Since cocoyam has been identified as a shade-tolerant crop (Caesar, 1980; Schaffer and O'Hair, 1987), the potential exists to use it as an understory crop in polyculture or agroforestry production systems (Juo, 1989). Multistory polyculture systems can lead to maximization of light interception and resource uti- lization. Information on cocoyam growth, ontogeny, phenol- ogy, and dry-matter partitioning patterns under differing photosynthetic photon flux (PPF) levels may assist in designing such systems. Field studies with cocoyam or related edible aroids

The effects of shade during leaf development on photosyntheti c activity of cocoyam (Xanthosoma sagitti- folium (L.) Schott) were investigated. Net gas exchange and N and chlorophyll concentrations were determined for cocoyam leaves growing in 30%, 50%, or 100% sunlight. Net CO2 assimilation (A) and water use efficiency (WUE) were greater for plants grown in 100% sunlight than for plants grown in less sunlight. Substomatal CO2 concentration increased with increased shading. Stomatal conductance (gs) and transpiration (E) did not vary significantly among treatments. Diurnal paterns for A were positively correlated with gs, lamina temperature, relative humidity, and photosynthetic photon flux (PPF). Lamina N concentrations, determined on lamina dry weight and lamina area bases, increased with increased PPF. Shade plants (30% and 50% sunlight) had greater chlorophyll : N ratios (dry-weight basis) and greater lamina area : lamina dry weight ratios than 100% sunlight-grown plants, which indicates increased photosynthate and N allocation to leaves of shade plants and maximization of light interception. Cocoyam has been identified as shade tolerant (Caesar, 1980; Schaffer and O'Hair, 1987). Therefore, the potential exists for use of this corm-producing species as an understory crop in polyculture systems. The effect of shading on photosyntheti c activity of cocoyam needs to be elucidated to identify optimal photosynthetic photon fluxes (PPF) for maximum yields of this crop. Other aroid species grown in moderate shade have equal (Miura and Osada, 1981), greater (Schaffer and O'Hair, 1987), or lower (Sims and Pearcy, 1989) A rates than sun-grown plants. Schaffer and O'Hair (1987) observed that 60% sunlight-grown cocoyam had greater A than 100% sunlight-grown plants. How- ever, their study focused on gas exchange of cocoyam grown at PPFs above the light saturation point for A (>750 µmol·s -1 ·m -2 ). Diurnal and seasonal gas exchange data are lacking for cocoyam growing at PPFs below the light saturation point. Lamina N and chlorophyll concentrations can affect A (Field, 1983). Chlorophyll is important for light harvesting while N is an important component of several photosynthetic enzymes (Field, 1983; Evans, 1989). To our knowledge, no information exists that evaluates the role of lamina chlorophyll and N on shade acclimation of cocoyam. Previous studies have shown that biomass accumulation and yield of cocoyam are greater for shade-grown than sun-grown plants (unpublished data). The purpose of this study was to determine if the shade-tolerance of cocoyam is related to gas exchange characteristics and to lamina N and chlorophyll con- tents of this crop species.

Net gas exchange and growth were determined for cocoyam (Xanthosoma sagittifolium (L.) Schott) growing in 30%, 50%, and 100% sunlight and fertilized with 0 or 475 mg N/kg nutrient solution. Interactions between N and shade were observed for lamina area per plant, top: corm ratio, corm weight, transpiration (E), stomatal conductance (g,), and lamina N and chlorophyll concentrations. When N treatments were pooled, shade-grown plants (30% and 50% sunlight) had greater lamina areas, lamina and petiole biomass, top : corm (fresh weight) ratios, and corm fresh weights than plants grown in full sunlight. All of these criteria also had higher values for plants that received the N- fertilizer solution (+ N) than for plants that received the N-free solution (- N), when shade treatments were pooled. When N treatments were pooled, 100%-sunlight plants had greater net CO2 assimilation (A) rates than shade plants. Water-use efficiency (WUE), A, g., and E for 100%-sunlight-grown plants were higher for + N than for - N plants. For shade plants, however, A and E were similar between N treatments. When N treatments were pooled, shade plants had a greater lamina chlorophyll concentration on a dry-weight basis than 100%-sunlight plants, whereas content on an area basis was similar among shade treatments. Among shade treatments, chlorophyll contents on an area and dry-weight basis were higher for + N than for - N plants. Plants grown in 100% sunlight had higher lamina N concentrations (area and dry-weight bases) than shade plants. The interactions between N and shade showed that cocoyam response to N depends on incident photosynthetic photon fluxes during growth. Lamina N concentration affects plant light utilization and ab- sorption, since N is a major constituent of assimilating tissues (Lawlor et al., 1989; Morgan, 1988; Seeman et al., 1987; Sin- clair and Horie, 1989) and is a component of ribulose bisphos- phate carboxylase, an important regulator of photosyntheti c activity (Bjorkman, 1972; Farineau et al., 1988; Lawlor et al., 1989; Suzuki et al., 1987). Lamina N concentration has been positively correlated with A for several plant species (Evans, 1989; Field and Mooney, 1986; Sinclair and Horie, 1989; Ter- ashima and Evans, 1988), including aroids such as Colocasia esculenta (Sims and Pearcy, 1989) and Alocasia macrorrhiza (Seeman et al., 1987; Sims and Pearey, 1989). Nitrogen allo- cation appears to be involved in acclimation of plants to high PPF (Ferrar and Osmond, 1986; Joiner et al., 1977; Osmond

Nutraceuticals are natural compounds that contain both nutritional as well as medicinal benefits. Various nutraceuticals (curcumin and resveratrol) obtained from plant extracts have been shown to improve fitness and extend lifespan by various mechanisms. In addition other compounds have also been shown to extend lifespan (rapamycin, spermidine and nicotinamide mononucleotide). Although the end result for these compounds maybe extension of lifespan, comparison of their signaling pathways remains to be determined. The objective of our research was to compare the signaling pathway of these compounds on both normal human T cells and Jurkat cell lines. We used RT-PCR to measure gene expression of NF-Κβ, AMPK, sirtuin 1-7 and autophagy specific genes (ATG5 and MAPILC3B/LC3) for all of these compounds. In addition, we show a direct correlation between concentrations of treatment and the upregulation of gene expression to the viability of the cells.

To determine Al and Ca effects on photosynthesis and chlorophyll fluorescence of taro [Colocasia esculenta (L.) Schott, cv. Lehua maoli] plantlets were grown hydroponically at four levels of Al (0, 440, 890, and 1330 µM) and two levels of Ca (100 and 1000 µM). Increasing Al levels significantly reduced leaf area, photosynthesis, maximum photochemical yield of photosystem II (PSII) (Fv/Fm), quantum yield of electron transport through PSII (o PSII), and photochemical quenching (qp). An increased Ca level significantly increased leaf area, Ca concentration in leaf blades, photosynthesis, Fv/Fm, and oPSII. The detrimental effect of excess Al on photosynthesis and Fv/Fm was ameliorated by high solution Ca. It was hypothesized that a high Ca level helped to stabilize thylakoid membrane structure against disruption by Al.

Telomeres are DNA-protein complexes at the ends of chromosomes that shorten during cell division, an occurrence that causes cellular senescence. Telomere shortening is offset by the action of a reverse transcriptase enzyme called telomerase, which can extend the DNA strands at the ends of chromosomes and delay cellular senescence. These observations have lead investigators to search for methods of stimulating telomerase activity in the hopes of delaying cellular senescence and extending cellular function. Currently, there are natural compounds proven to activate telomerase activity, i.e., TA-65 and TAT2. Both compounds are extracts from the plant Astragalus membranaceus, which is commercially available. Different formulations for Astragalus membranaceus can be obtained. The objective of this research was to compare two products, TA-65 and HTA (both extract of Astragalus membranaceus) for their ability to activate telomerase activity and their affect on cellular growth on both CD4 and CD8 T cell cultures. The results of our study indicate that TA-65 was able to induce telomerase activity 1.4-3.3x fold relative to controls, whereas HTA showed increases in telomerase activity up to 1.3x-fold only in two donors but did not reach statistical significance. In addition we demonstrate that T cells treated with TA-65 had increase cell growth within 7 days of culturing, again HTA also showed increases in cell growth but did not reach statistical significance.

Various natural products have been proposed to both increase health at the organismic level, and delay the onset of cellular aging. Of particular interest is resveratrol, a phytoalexin that has been demonstrated to have cardioprotective effects and to slow the progression of a variety of illnesses, including various types of cancers. More recently, resveratrol has been demonstrated to increase the maximum lifespan of model organisms, such as C. elegans, D. melanogaster and N. furzeri. However, the potential health benefits of resveratrol and other similar compounds on the human immune response have not been adequately addressed. We have, therefore, initiated research to determine the in vitro effects of the nutraceuticals resveratrol, and its analogs (polydatin and acetyl-resveratrol), as well as curcumin on a variety of human T cell functions. In this study we evaluated the effect of these compounds on proliferative potential, telomerase activity, expression of costimulatory and memory surface markers and sirtuin gene expression profiles of both human CD4 and CD8 T cells. Our data show that these compounds stimulated strong dose-dependent anti-inflammatory responses, and upregulated surface protein markers associated with the suppression of T cell activity. Our preliminary results suggest that these compounds may function to down-modulate ongoing CD4 and CD8 immune activity, while, nevertheless, poising the T cells for a subsequent immune response.

Home gardening is a popular year-round recreational activity in Hawaii that helps to increase community food security in suburban and rural communities where high levels of poverty and unemployment exist. Updated fertilizer recommendations and accurate information about the latest products allows home gardeners to improve crop growth, and to minimize nutrient imbalances in the soil, pest problems, and environmental risks from nutrient runoff or leaching. Two field experiments were conducted in Oahu, Hawaii, to evaluate several new products in the market for the production of two home-garden Chinese cabbage varieties. The treatments included Miracle Grow, a new Miracle Grow Plus formulation, Plant Power 2003 nutrient solution, a Maui Liquid Compost product, and a standard fertilizer control (150 kg·ha-1 N rate). Each treatment consisted of a 6-m long row with 30-cm plant spacing in the row. Each treatment was replicated four times in a completely randomized block design, for a total of 40 plots (two varieties × five treatments × four replications). Data collected included soil fertility before initiation and after experiment completion, tissue nutrient analysis, plant height collected twice during the growing cycle, and head weight and length measured at harvest time. The variety Pagoda was more responsive to fertilizer applications, showing an average of 30% yield increases between the best and poorest treatment, compared to 20% for `China Express'. Overall, the Miracle Grow formulations outperformed the other products. The tissue nutrient data showed tissue nutrient levels above those recommended by the Extension Service. The treatments with highest yield response also showed greater symptoms of “black heart” from possible boron deficiency.

Regulatory agencies are concerned about the high levels of P fertilizers used in some agricultural areas because of potential runoff to aquatic habitats. Farmers in Hawaii traditionally make blanket P applications even in soils high in P. Many farmers, especially those growing leafy crops, claim to observe responses to P, especially during the cooler winter months. A series of 15 field experiments were conducted over a 2-year period to evaluate the response of three mustard cabbage varieties to five P fertilizer rates across three locations in the state, and across several planting seasons. All experiments were conducted in soils with P levels that the University of Hawaii determined to be high in P. The experimental design for each experiment consisted of three commercial mustard cabbage varieties, and five P application rates (from 0 to 400 kg·ha-1 of TSP). Each plot consisted of a 3-m double-row, with plants spaced 15 cm within the row, and 30 cm between rows, with four replications per treatment. Each experiment thus consisted of 60 plots (three varietie × five P rate × four replications). After the initial P applications were made on each site, three consecutive crops were planted on the same site without making any additional P applications. Data collected included soil fertility prior to initiation and after experiment completion, tissue nutrient levels, plant height during crop establishment, and individual head weight of 20 plants per treatment. Our data show that even in soils with initial high levels of P, mustard cabbage responded to P applications, especially at high elevations and during the cooler months of the year. From this data we recommend that the University recalibrate its P fertilizer recommendations for leafy vegetable production in Hawaii.

A major issue in the preparation of nutrient budgets for organic farmers is the residual nutrient effect from organic amendments available for follow-up crops in year-round rotation systems. A series of separate experiments were conducted to evaluate: 1) the residual nutrient effects on double-cropped sweet corn from initial applications of several organic amendments locally available in Oahu, Hawaii; 2) the residual effect of double cropped zucchini; and 3) mustard cabbage from the application of similar organic amendments. The sweet corn experiment consisted of six treatments, with organic amendments applied only prior to the first planting. The second follow-up sweet corn planting was grown without additional amendment applications. Treatments included: 1) a fruit fly based compost; 2) aged chicken manure; 3) bone meal; 4) synthetic fertilizer (farmer's practice); 5) a combination of compost and fertilizer; and 6) a combination of compost and chicken manure. The experiment was arranged with a randomized complete-block design. Each treatment plot consisted of two 20-m long rows of corn with five replications per plot for a total of 30 treatment plots. On a separate location similar trials were conducted on long-term organic farming plots, with double cropped zucchini and with double cropped mustard cabbage. The results from this research shows that crop yields were similar or greater under the organic amendment plots compared to the synthetic fertilizer plots. In crops with a high N uptake demand, yields from the organic amendment plots declined by about 10% in follow-up plantings. This data will allow organic farmers to prepare nutrient budgets to better match their organic fertilizer applications with crop nutrient demands.

Pink root (Phomaterrestris) is among the major limiting factors for the production of sweet onions on Maui, Hawaii. Few management options exist for the control of pink root in onions. Two split-plot experiments were conducted in the area of Kula, Maui, over 2 years to evaluate several alternative management practices. In Expt. 1, the main plots were a rotation with cabbage, solarization with a clear plastic mulch, and a fallow period. Subplots were plus or minus Vapam fumigation. Sub-subplots were biomass application of Sudex or rape, inoculation with an EM biostimulant, and control. Each treatment had four replications for a total of 96 plots. In the follow-up experiment, the main plots were Vapam fumigation, rotation with either a Sudex or rape cover crop, and controls. The subplots were plus or minus EM biostimulant application. In Expt. 1, three separate treatments: solarization, cabbage rotation, and Sudex incorporation had a synergistic effect with Vapam fumigation. Fumigation and solarization also decreased pink root incidence. Rape contributed to a decreased disease incidence while EM contributed to increased bulb size. In Expt. 2, EM and rape contributed to increased yields. Rape and sorghum rotations contributed to decreased pink root incidence. EM inoculation had differential effects on several diseases, contributing to reduced bacterial bulb rot levels. The data indicate that growers may have several alternative management tools at their disposal, in addition to proper varietal selection, to improve yields and reduce disease incidence in sweet onions.

As many farmers transition toward organic farming, research-based information is required to determine the appropriate rates and timing for the application of available organic fertilizers. Four experiments were conducted over a 3-year period in Oahu, Hawaii, to evaluate the effect of five different organic amendments on the growth and yield of edible ginger. Fertilizer amendments, applied at a rate of 30–60 t·ha-1, included bone meal, a locally available commercial chicken manure-based compost, a commercial Bokashi compost, aged chicken manure, synthetic fertilizer (farmer's practice at 300 kg·ha-1 N), and a control. Each treatment plot consisted of a 10-m row with 15 plants per plot, and five replications per treatment. Ginger was planted in April of every year, and harvested from February to March of the following year. Data collected included soil fertility before initiation and after experiment completion, tissue nutrient levels, plant stands, plant height, and stem number, individual tops and root weight of 5–10 plants per treatment, as well as nematode counts before and after experiment completion. The data showed that similar or greater root weight yields and quality were obtained with the use of organic amendments compared to the use of synthetic fertilizer. Increased yields were obtained when organic amendment and fertilizer applications were split over the growing season. Data will be presented with regard to initial plant stands, tissue levels, and yield trends in response to the several amendments used in these experiments, and management considerations for farmers will be discussed.

The sensory quality of fresh basil (cv. Sweet Italian) was evaluated to determine if compost or mineral fertilizer applications affected flavor and aroma intensity. The four treatments, arranged in a randomized complete-block design with three replications, were: compost applied at 50 t·ha–1; compost applied at 200 t·ha–1; mineral N applied at 110 kg·ha–1; and a control receiving no amendment. Leaves from the first four nodes of young shoots were used in the evaluation. Twelve trained panel members scored samples of three leaves from each treatment for aroma and flavor intensity using a linear scale, converted to a scale of 1–10 where 1 = much less intense than a reference sample (control), and 10 = much more intense than the reference. No significant difference between treatments was found in flavor intensity. Significant difference between treatments in aroma intensity was found. Aroma scores were highest in samples from the compost and synthetic fertilizer treatments, and lowest in those from the control. Scores for aroma from the compost and synthetic fertilizer treatments were similar to each other. Aroma intensity increased with increased rate of compost application. No significant correlation was found between aroma intensity and plant tissue N content, sap NO3– levels, or yield.

To help develop fertilizer recommendations for organic vegetable production in Hawaii, the effects of organic amendments on basil yield were studied in two experiments. The treatments were synthetic nitrogen applied at 100 kg·ha–1 per crop, organic amendments applied at a rate of 8–160 MT·ha–1, and an unammended control. Each treatment was replicated four times in a RCB design. In the first experiment, chicken manure was the organic amendment at 8 MT·ha–1 with a single basil variety grown. In the second experiment, conducted at the same location immediately following the first experiment, the organic amendment was locally produced compost (0.3% N) applied at 40 and 160 MT·ha–1 with three basil varieties grown. Data taken included soil fertility levels before and after experimental completion, marketable yields recorded weekly over 5–10 weeks, and tissue N and nitrate sap analysis measured at two to three different plant growth stages. In the first experiment, treatments receiving chicken manure or synthetic N showed similar yields (256–289 g/plant), which were significantly greater than the control (197 g/plant). Tissue N levels were greatest in the synthetic fertilizer treatment (4.9%) and lowest in the control (4.5%). In the second experiment, there was a differential response by varieties to treatments with respect to yields. Yields from the compost treatments (292–700 g/plant) were equal to or greater than those receiving synthetic fertilizer (320–651 g/plant) and were generally greater than the control (324–532 g/plant). Tissue N levels were greatest in plants receiving synthetic fertilizer (4.6% to 4.7%) and lowest in the control (4.3% to 4.4%). A positive correlation was found between lab tissue N levels and nitrate sap analysis determination.

In the tropics, weed control is a year-round concern. The use of cover crops in a conservation tillage system allows for the production of a crop biomass that can be killed and mowed, and later used as mulching material to help reduce weed growth. This study compared yields of three vegetable species grown in two conventional tillage systems, one weeded and one unweeded control, and in two no-tillage treatments using two different cover crop species, oats (Avena sativa L. `Cauyse') and rye grain (Secale cereale L.). The cover crops were seeded (112 kg/ha) in Spring 1998 in 4 × 23-m plots in a RCB design with six replications per treatment, and mowed down at the flowering stage before transplanting the seedlings. Data collection throughout the experimental period included quadrant weed counts, biomass levels, and crop marketable yields. Weed suppression was compared with the yields of the vegetable crops. The greatest vegetable yields were in the conventionally hand-weeded control and the worst in the un-weeded controls. Weed species composition varied depending on the cover crop species treatment. The rye better suppressed weed growth than the oats, with greater control of grass species. Rye, however, suppressed romaine and bell pepper yields more than the oat treatments. Similarly greater eggplant yields and more fruit per plant were found in the oat treatment than in the rye. Both cover crops suppressed weed growth for the first month; however, by the second month most plots had extensive weed growth. This study showed that at the given cover crop seeding rate, the mulch produced was not enough to reduce weed growth and provide acceptable yields of various vegetable crops.

Little nutrient calibration data exists for the production of vegetables in the tropics. Replicated experiments were conducted to evaluate the effect of several N application rates on the yield of head cabbage, Japanese eggplant, an old open-pollinated determinate tomato cultivar, and of `Merced', a standard commercially grown determinate tomato hybrid. Data collected included soil nutrient analysis prior to experiment initiation, tissue nutrient analysis, nutrient sap analysis for eggplant, canopy dimensions for eggplant and tomato, and marketable yields. Additional data collected in tomato included both laboratory tissue nutrient analysis and NO3 and K+ determinations, through rapid sap analysis kits, collected during three crop growth stages, ripened fruit soluble solid determinations, and NO3 determinations at three soil depths conducted ≈2 weeks after the last harvest. Yields of head cabbage, grown at about 360 m elevation, were not affected by N application rates ranging from 0 to 300 kg N/ha. Eggplant was grown at sea level in a soil rich in organic matter. Eggplant yields from an 8-month harvest period were little affected by N rates ranging from 0 to 300 kg·ha–1, except for a trend toward greater yields with the highest N rates, during the last 4 months. In tomato, the old OP variety was less responsive to N than the newer tomato hybrid. Greatest `Merced' tomato yields were obtained with 100 to 200 kg N/ha in treatments ranging from 0 to 400 kg N/ha. Our data indicate that acceptable yields are obtained with modest N application rates, and that excessive N applications by commercial growers may result in nitrate leaching, and in unnecessary fertilizer application expenses.

Portable chlorophyll fluorometers have made it possible to evaluate the photosynthetic efficiency of photosystem 11 for vegetable crops under ambient conditions. A sampling protocol was first established to eliminate variability due to positioning of the fiber optics in relation to the leaf, leaf selection, and natural environmental variability. Fluorescence parameters of the quantum yield of noncyclic electron transport (DF/Fm') and electron transport rate (ETR) were taken from several economically important vegetables under ambient conditions between 11 and 14 h. The objective of the second part of the study was to conduct in situ chlorophyll fluorescence and biomass determinations as affected by salt stress and N deficiency. DF/Fm' and ETR were studied in rhizobium inoculated, noninoculated and inorganic N-fed soybean and differences in fluorescence were related to yield. The influence that salt stress, and several N rates have on fluorescence photochemical quenching (qP) and nonphotochemical quenching (qN), NPQ ([Fm-Fm']/Fm'), DF/Fm' and ETR for hydroponically grown lettuce will also be presented.

Experiments conducted over 3 years have determined the potential of utilizing Indian mustard and `Tastie' head cabbage multi-species borders as trap crops for management of caterpillar pests of head cabbage in Hawaii. `Scorpio', a cultivar that showed less feeding damage than `Tastie', was used as the main crop. The studies point toward the use of isolated patches of multi-species attractant crops separated from the main crop by a buffer of non-host crops such as sweet corn. A sweet corn buffer was effective in preventing insect movement between plots. Initial studies showed the high susceptibility of Indian mustard to white rust (Albugo candida), to be a constraint to its use as a trap crop. Follow-up studies found that `Excel' and `Parkland' mustards may be adequate substitutes for mustard crop due to their attraction of caterpillars and their tolerance to white rust. Gradient experiments conducted on 60 × 30-m plots indicate that the trap crop may be effective for a distance of 25 to 30 m in terms of attraction of caterpillars and dispersal of beneficials into the main crop. A record was also made of growth, flowering patterns, and of beneficials hosted by 12 different Brassica cultivars during the winter and spring growing seasons.

Experiments were conducted to evaluate the effect of two different compost materials and several compost: synthetic N fertilizer ratios on the growth, yields, and nematode infestations in head and semi-head lettuce, and basil. Treatments were homemade compost at 25 MT/ha, Amend compost at 25 MT/ha, N alone at 150 kg·ha–1, and Amend compost at 25 MT/ha plus 0, 100, 200 or 300 kg N/ha. The basil trial followed the lettuce experiment on the same treatment beds to evaluate the long-term effects of compost applications. Compost plus 100 kg N/ha resulted in the greatest yields of 12 to 24 MT/ha for the semi-head and head lettuce trials, respectively. Basil was harvested for 6 months during a 10-month growth cycle. Highest basil yields of 64 MT/ha and canopy growth were obtained with a combination of compost plus synthetic N fertilizer, with 300 kg N/ha required for maximum yields during the 6-month harvesting period. By the last sampling date nematode counts were lowest for plots that received compost treatment alone and highest for the controls and for plants receiving synthetic N fertilizer alone.

The diamondback moth (DBM). Plutella xylostella, is the number one pest of cabbage in the the world. The pest is resistant to most pesticides registered for its use, and resistance has also been detected in several areas for registered biopesticides. Four experiments were conducted to: 1) Determine the tolerance to DBM feeding among 20 commercial head cabbage cultivars, 2) Evaluate the effect of three nitrogen fertility levels on DBM numbers. and 3) Evaluate the effect of Indian mustard. Brassica juncea trap crops as a tool to manage DBM populations in head cabbage agroecosystems. Experiments were conducted at University of Hawaii experiment stations located in Kamuela. Hawaii, and in Kula, Maui. The trap crop treatments consisted of planting two border rows of Indian mustard in cabbage field borders. Three or 4 biweekly insect counts were conducted for each trial. Insect counts consumed of destructive sampling of 3-6 plants per plot and determination of larvae and pupae number and parasitation levels. The nitrogen studies found more DBM in monoculture cabbage receiving 300 kg Ha-1 N than in controls even though cabbage yields did not vary among treatments. A range of tolerance to DBM feeding was found among the cultivars tested. The trap crop system was shown to be more effective during the summer than in the winter months. Data indicates that the trap crop also acted as attractant for beneficial insects, which may aid in the biological control of DBM in cabbage

Living mulches offer a low-input alternative to achieve weed control while minimizing herbicide applications, decreased fertilizer leaching, insect and nematode management. and improved soil texture. A study was conducted to evaluate the effect of a Rhodes Grass (Chloris gayana cv. Katambora) living mulch on the growth and productivity of ten eggplant. Solanum melongena, cultivars grown under fertigation. The living sod was established at the Univ. Hawaii Waimanalo Experiment Station in June 1992. Soil analysis was taken before experiment initiation. Ten eggplant cultivars were transplanted on both living-mulch and control (woven-polyethelene mulch) plots on 4 March 1993. Weekly or bi-weekly harvests were conducted for six months. beginning on 19 May 1993. In addition plant height and canopy dimensions were determined on 16 April. and 10 Nov. Plant growth was monitored throughout the experiment. Soil samples were taken from the eggplant rhizosphere, hare-ground and in Rhodes grass monoculture, for nematode count determinations. Soil samples were also taken for nutrient determination after completion of the experiment. Overall yields were greater in the polyethelene mulch than in the living mulch plots. A differential response was observed on the response of cultivars to cropping system. However the most vigorous cultivars performed well in both systems. The living mulch system showed potential for nematode management in eggplant agroecosystems.

Methanol sprays reportedly increased yields of several crops in Arizona by 50 to 100 percent (Nonomura and Benson PNAS 89:9794(1992). Reports from other parts of the country have shown conflicting results with regards to the effect of methanol sprays on yields of horticultural crops. Several greenhouse and growth chamber (controlled temperature. day length, and photosynthetic photon flux) experiments were conducted to evaluate the effect of methanol sprays on the growth and productivity of several vegetable crops in Hawaii. Treatment spray solutions consisted of 20-25% methanol, 0.5% low biuret urea. 0.001% chelated iron, and 0.02% surfactant. Control sprays only contained urea, chelated iron, and surfactant. Each experiment consisted of at least 5 weekly methanol sprays. Flowering cabbage, Brassica campestris var. parachinensis, had greater biomass production when sprayed with methanol in the late summer months. Similar results were obtained with choi sum in a 2 by 2 factorial experiment with methanol and water stress treatments. However, choi sum did not respond to methanol treatments in follow-up greenhouse trials. perhaps attributable to the shorter and Overcast days experienced in the fall and winter. Okra, chili pepper, and eggplant showed no response to methanol sprays. Okra showed a trend toward increase yields in response to methanol sprays, but differences were not significant. Follow-up studies in the greenhouse and in the field, which include evaluation of photosynthetic efficiency through chlorophyll fluorescence determinations will be presented.