2014-2016 seasonal rainfall effects on metals in tea (Camelia sinensis (L.) Kuntze).

Plant-climate interactions affect the edible crop composition, impacting flavor, nutrition, and overall consumer liking. In this study, principal components analysis was used to assess the macro- and micronutrient metal concentrations in pre-monsoon (spring), monsoon (summer), and post-monsoon (autumn) tea (Camelia sinensis (L.) Kuntze) from Yunnan Province, China in 2014-2016. Statistical differences were observed (p = 1.35E-24). Fe, Ca, Mg, Mn, Al, and Ba concentrations were higher in June (monsoon) than in March (pre-monsoon) and September (post-monsoon) compared to Pb, K, Cu, Zn, and Na, which were higher in March and September. Although Fe, Ca, Mg, Mn, Al, and Ba concentrations increased during the monsoon season, sensory analysis did not detect metallic taste in either minimally processed or farmer-processed (commercial) teas. This finding shows the seasonal differences in flavor were due to striking differences in organic chemical composition and concentration.

Striking changes in tea metabolites due to elevational effects.

Climate effects on crop quality at the molecular level are not well-understood. Gas and liquid chromatography-mass spectrometry were used to measure changes of hundreds of compounds in tea at different elevations in Yunnan Province, China. Some increased in concentration while others decreased by 100's of percent. Orthogonal projection to latent structures-discriminant analysis revealed compounds exhibiting analgesic, antianxiety, antibacterial, anticancer, antidepressant, antifungal, anti-inflammatory, antioxidant, anti-stress, and cardioprotective properties statistically (p = 0.003) differentiated high from low elevation tea. Also, sweet, floral, honey-like notes were higher in concentration in the former while the latter displayed grassy, hay-like aroma. In addition, multivariate analysis of variance showed low elevation tea had statistically (p = 0.0062) higher concentrations of caffeine, epicatechin gallate, gallocatechin, and catechin; all bitter compounds. Although volatiles represent a small fraction of the total mass, this is the first comprehensive report illustrating how normal variations in temperature, 5 °C, due to elevational effects impact tea quality.

Metabolite profiling of Camellia sinensis by automated sequential, multidimensional gas chromatography/mass spectrometry reveals strong monsoon effects on tea constituents.

Seasonal variation in tea (Camellia sinensis (L.) Kuntze; Theaceae) chemistry was investigated using automated sequential, multidimensional gas chromatography/mass spectrometry (GC-GC/MS). Metabolite libraries were produced for teas harvested from the Bulang Mountains in Yunnan, China before and after the onset of the East Asian Monsoon. A total of 201 spring and 196 monsoon metabolites were identified, with 169 common and 59 seasonally unique compounds. An additional 163 metabolites were detected but their identity could not be confirmed. Spectral deconvolution of GC/MS data was used to measure the relative concentrations in the teas. Within each family individual metabolite concentrations increased, decreased and stayed the same. The major constituents in both teas were linalool (28%), geraniol (13%), α-terpineol (10%), hotrienol (4%) and nerol (3%). This work provides the foundation to monitor seasonal variations of tea chemistry.

Effects of extreme climate events on tea (Camellia sinensis) functional quality validate indigenous farmer knowledge and sensory preferences in tropical China.

Climate change is impacting agro-ecosystems, crops, and farmer livelihoods in communities worldwide. While it is well understood that more frequent and intense climate events in many areas are resulting in a decline in crop yields, the impact on crop quality is less acknowledged, yet it is critical for food systems that benefit both farmers and consumers through high-quality products. This study examines tea (Camellia sinensis; Theaceae), the world's most widely consumed beverage after water, as a study system to measure effects of seasonal precipitation variability on crop functional quality and associated farmer knowledge, preferences, and livelihoods. Sampling was conducted in a major tea producing area of China during an extreme drought through the onset of the East Asian Monsoon in order to capture effects of extreme climate events that are likely to become more frequent with climate change. Compared to the spring drought, tea growth during the monsoon period was up to 50% higher. Concurrently, concentrations of catechin and methylxanthine secondary metabolites, major compounds that determine tea functional quality, were up to 50% lower during the monsoon while total phenolic concentrations and antioxidant activity increased. The inverse relationship between tea growth and concentrations of individual secondary metabolites suggests a dilution effect of precipitation on tea quality. The decrease in concentrations of tea secondary metabolites was accompanied by reduced farmer preference on the basis of sensory characteristics as well as a decline of up to 50% in household income from tea sales. Farmer surveys indicate a high degree of agreement regarding climate patterns and the effects of precipitation on tea yields and quality. Extrapolating findings from this seasonal study to long-term climate scenario projections suggests that farmers and consumers face variable implications with forecasted precipitation scenarios and calls for research on management practices to facilitate climate adaptation for sustainable crop production.

Effects of different potato cropping system approaches and water management on soilborne diseases and soil microbial communities.

Four different potato cropping systems, designed to address specific management goals of soil conservation, soil improvement, disease suppression, and a status quo standard rotation control, were evaluated for their effects on soilborne diseases of potato and soil microbial community characteristics. The status quo system (SQ) consisted of barley underseeded with red clover followed by potato (2-year). The soil-conserving system (SC) featured an additional year of forage grass and reduced tillage (3-year, barley/timothy-timothy-potato). The soil-improving system (SI) added yearly compost amendments to the SC rotation, and the disease-suppressive system (DS) featured diverse crops with known disease-suppressive capability (3-year, mustard/rapeseed-sudangrass/rye-potato). Each system was also compared with a continuous potato control (PP) and evaluated under both irrigated and nonirrigated conditions. Data collected over three potato seasons following full rotation cycles demonstrated that all rotations reduced stem canker (10 to 50%) relative to PP. The SQ, SC, and DS systems reduced black scurf (18 to 58%) relative to PP; SI reduced scurf under nonirrigated but not irrigated conditions; and scurf was lower in DS than all other systems. The SQ, SC, and DS systems also reduced common scab (15 to 45%), and scab was lower in DS than all other systems. Irrigation increased black scurf and common scab but also resulted in higher yields for most rotations. SI produced the highest yields under nonirrigated conditions, and DS produced high yields and low disease under both irrigation regimes. Each cropping system resulted in distinctive changes in soil microbial community characteristics as represented by microbial populations, substrate utilization, and fatty acid methyl-ester (FAME) profiles. SI tended to increase soil moisture, microbial populations, and activity, as well result in higher proportions of monounsaturated FAMEs and the FAME biomarker for mycorrhizae (16:1 ω6c) relative to most other rotations. DS resulted in moderate microbial populations and activity but higher substrate richness and diversity in substrate utilization profiles. DS also resulted in relatively higher proportions of FAME biomarkers for fungi (18:2 ω6c), actinomycetes, and gram-positive bacteria than most other systems, whereas PP resulted in the lowest microbial populations and activity; substrate richness and diversity; proportions of monounsaturated and polyunsaturated FAME classes; and fungal, mycorrhizae, and actinomycete FAME biomarkers of all cropping systems. Overall, soil water, soil quality, and soilborne diseases were all important factors affecting productivity, and cropping systems addressing these constraints improved production. Cropping system approaches will need to balance these factors to achieve sustainable production and disease management.

Phosphorus forms in conventional and organic dairy manure identified by solution and solid state p-31 NMR spectroscopy.

Organic dairy production has increased rapidly in recent years. Organic dairy cows (Bos taurus) generally eat different diets than their conventional counterparts. Although these differences could impact availability, utilization, and cycling of manure nutrients, little such information is available to aid organic dairy farmers in making nutrient and manure management decisions. In this study, we comparatively characterized P in organic and conventional dairy manure using solution and solid state (31)P NMR spectroscopic techniques. Phosphorus in both types of dairy manure was extracted with water, Na acetate buffer (100 mmol L(-1), pH 5.0) plus 20 mg Na dithionite mL(-1), or 0.025 mol L(-1) NaOH with 50 mmolL(-1) EDTA. Solution NMR analysis revealed that organic dairy manure contained about 10% more inorganic phosphate than conventional dairy manure. Whereas organic dairy manure did contain slightly more phytate P, it contained 30 to 50% less monoester P than conventional dairy manure. Solid state NMR spectroscopy revealed that mono-, di-, and trivalent metal P species with different stabilities were present in the two dairy manures. Conventional dairy manure contained relatively higher contents of soluble inorganic P species and stable metal phytate species. In contrast, organic dairy manure contained more Ca and Mg species of P. These results indicate that P transformation rates and quantities should be expected to differ between organic and conventional dairy manures.

Effectiveness and efficacy of conservation options after potato harvest.

Soil erosion and phosphorus (P) runoff can be severe in potato production systems in the Northeast USA, which are characterized by intensive tillage, minimal ground cover, low crop residue return, and steep slopes. We used rainfall simulators in the greenhouse and field to assess sediment and P movement associated with two conservation practices: straw mulching and application of polyacrylamide (PAM). In the greenhouse, a Nokomis sandy loam soil (fine-loamy, mixed, frigid Typic Haplorthods) was packed into 0.2 by 1.0 m boxes and subjected to four rainfall events at an intensity of 70 mm h(-1). Runoff amount, sediment concentration, and inorganic and sediment-bound P were measured for 30 min after initiation of runoff. Linear increases in straw mulch biomass (up to equivalent of 3000 kg ha(-1)) resulted in exponential decreases in sediment and P loss. Mulch applied at rates as low as 600 kg ha(-1) provided nearly 50% ground cover and reduced sediment movement and sediment-bound P concentration and loss by >50%. Higher application rates reduced sediment loss by up to 95% but contributed dissolved reactive P (DRP) to runoff water. Field observations using simulated rainfall on mulch-covered and bare soil were consistent with greenhouse results. Linear increases in PAM application rate (to 20 kg ha(-1)) also reduced sediment loss. The efficacy of this practice decreases slightly with successive rainfall events but still had significant benefit through four simulated rainfalls on soil packed into boxes. This was not the case in the field where the effect of PAM was limited to the first two rainfall events. In general, runoff volume was not strongly influenced by any of these practices, and most of the P loss was comprised of sediment-bound P. Both conservation practices are effective at reducing soil and nutrient loss in intensive potato systems.

Three-dimensional concentration mapping of gases using a portable mass spectrometer system.

The visualization of hazardous gaseous emissions at volcanoes using in-situ mass spectrometry (MS) is a key step towards a better comprehension of the geophysical phenomena surrounding eruptive activity. In-situ data consisting of helium, carbon dioxide, sulfur dioxide, and other gas species, were acquired with a quadrupole based MS system. Global position systems (GPS) and MS data were plotted on ground imagery, topography, and remote sensing data collected by a host of instruments during the second Costa Rica Airborne Research and Technology Applications (CARTA) mission. This combination of gas and imaging data allowed three-dimensional (3D) visualization of the volcanic plume and the mapping of gas concentration at several volcanic structures and urban areas. This combined set of data has demonstrated a better tool to assess hazardous conditions by visualizing and modeling of possible scenarios of volcanic activity. The MS system is used for in-situ measurement of 3D gas concentrations at different volcanic locations with three different transportation platforms: aircraft, auto, and hand-carried. The demonstration for urban contamination mapping is also presented as another possible use for the MS system.

Proteomic mapping of 4-hydroxynonenal protein modification sites by solid-phase hydrazide chemistry and mass spectrometry.

The modification of proteins by the cytotoxic, reactive aldehyde 4-hydroxynonenal (HNE) is known to alter protein function and impair cellular mechanisms. In order to identify susceptible amino acid sites of HNE modification within complex biological mixtures by microcapillary liquid chromatography and linear ion trap tandem mass spectrometry, we have developed a solid-phase capture and release strategy that utilizes reversible hydrazide chemistry to enrich HNE-modified peptides. To maximize the detection of fragment ions diagnostic of HNE modification, both neutral loss-dependent acquisition of MS/MS/MS spectra and the pulsed Q dissociation operation mode were employed. When the solid-phase hydrazide enrichment strategy was applied to a yeast lysate treated with HNE, 125 distinct amino acid sites of HNE modification were mapped on 67 different proteins. The endogenous susceptibility of many of these proteins to HNE modification was demonstrated by analyzing HNE-treated yeast cell cultures with a complementary biotin hydrazide enrichment strategy. Further analysis revealed that the majority of amino acid sites susceptible to HNE modification were histidine residues, with most of these sites being flanked by basic amino acid residues, and predicted to be solvent exposed. These results demonstrate the effectiveness of this novel strategy as a general platform for proteome-scale identification of amino acid sites susceptible to HNE modification from within complex mixtures.

Phosphorus distribution in dairy manures.

The chemical composition of manure P is a key factor determining its potential bioavailability and susceptibility to runoff. The distribution of P forms in 13 dairy manures was investigated with sequential fractionation coupled with orthophosphate-releasing enzymatic hydrolysis. Among the 13 dairy manures, manure total P varied between 4100 and 18,300 mg kg(-1) dry matter (DM). Water-extractable P was the largest fraction, with inorganic phosphorus (P(i)) accounting for 12 to 44% of manure total P (1400-6800 mg kg(-1)) and organic phosphorus (P(o)) for 2 to 23% (130-1660 mg kg(-1)), respectively. In the NaHCO(3) fraction, P(i) varied between 740 and 4200 mg P kg(-1) DM (4-44% of total manure P), and P(o) varied between 340 and 1550 mg P kg(-1) DM (2-27% of total manure P). In the NaOH fraction, P(i) fluctuated around 200 mg P kg(-1) DM, and P(o) ranged from 130 to 630 mg P kg(-1) DM. Of the enzymatically hydrolyzable P(o) in the three fractions, phytate-like P dominated, measuring 26 to 605 mg kg(-1) DM, whereas monoester P and DNA-like P were relatively low and less variable. Although concentrations of various P forms varied considerably, significant correlations between manure total P and certain P forms were observed. For example, H(2)O-extracted P(i) was correlated with total manure P (R(2) = 0.62), and so was NaOH-extracted P(o) (R(2) = 0.81). Data also show that the amount of P released by a single extraction with sodium acetate (100 mM, pH 5.0) was equivalent to the sum of P in all three fractions (H(2)O-, NaHCO(3)-, and NaOH-extractable P). Thus, a single extraction by sodium acetate buffer could provide an efficient evaluation of plant-available P in animal manure, while the sequential fractionation approach provides more detailed characterization of manure P.