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Fruit colour is a key quality trait in chilli pepper (Capsicum annuum), and carotenoids are the major pigments responsible for conferring the red colour observed in pepper fruits. Carotenoids have valuable antioxidant properties. Post-harvest storage of peppers is often required in order for consumer demand to be met, and therefore peppers must retain their quality during storage. An understanding of changes in carotenoid content is essential for high quality carotenoid retaining lines to be bred. In the present study, the mechanisms underlying the carotenoid retention trait have been investigated. Biochemical profiling, employing both HPLC-PDA and GC-MS has revealed changes in carotenoid content in the fruit of a Doubled Haploid population (375 associated lines), and has revealed that the carotenoid retention trait and intermediary metabolism are not linked. Physiological analysis of fruits has revealed the role of the fruit cuticle in controlling the carotenoid retention phenotype. The fruit cuticle protects fruit from carotenoid degradation by acting as a barrier to harmful oxidative species, which can result in non-enzymatic carotenoid cleavage. Transcriptomic analyses have resulted in the identification of candidate genes underlying the carotenoid retention trait, and a method of Virus Induced Gene Silencing (VIGS) has been established in pepper fruit for functional characterisation of genes, and validated in tomato. This study sheds light on a previously understudied trait. Understanding the mechanisms underlying carotenoid retention in chilli pepper will not only result in breeding of improved pepper varieties, but this information may also be translated to other crops, which also experience costly post-harvest carotenoid degradation, and consequently, reduced antioxidant properties and nutritional content.

A total of 15 endophytic genera were genomically identified in this study by culturing methods across three leaf tissue sampling dates, spanning from February to April 2023 in which 96 leaves were sampled. Identification was done using a PCR assay with primers specific to fungi and bacteria, followed by sequencing and identification of the PCR products. Of these 15 genera identified, 12 were not previously known to be associated with any Lycium species. Being novel research, all 15 genera identified were previously unreported as being present in L. ferocissimum. 13 were fungal and 2 were bacterial. Endophyte composition was dynamic, but overall diversity did not change considerably. The dominant genera in this study were Alternaria (50%) and Stemphylium (30%), with Neodidymelliopsis (7%) and Cladosporium (4%) making up the only 4 genera present on all 3 sampling dates. A qPCR assay was used to test each sample leaf used in this study for the presence of CaLso. The presence of CaLso in leaf samples increased from the February sampling group (1.7% positive) to April (33%), despite a considerable decrease in TPP population presence on the plants in that same period. Unexpectedly, the control group of asymptomatic leaves, also sampled in April, had the highest relative frequency of positive leaf samples (44.5%).

Graft incompatibility is a poorly understood phenomenon that presents a severe agricultural challenge. Unlike immediate incompatibility that results in rapid death, delayed incompatibility can take months or even years to manifest, creating a significant problem for perennial crop production. To investigate graft compatibility, we utilized the Solanaceae family due to its agriculturally relevant grafted crops, short life cycles and small stature. Additionally, Solanaceae contains within it a model species, Solanum lycopersium (tomato), which possesses a suite of genetic tools such as a sequenced genome and efficient transformation protocol. To first understand graft compatibility within Solanaceae, we performed a reciprocal graft trial with 4 economically relevant crops and found that most of these heterografts are capable of surviving but are incompatible due to failed vascular reconnections. Next, we utilized a novel model system: Solanum lycopersicum (tomato) and Capsicum annuum (pepper) to investigate delayed graft incompatibility. We employed classical techniques such as vascular staining and physiological measurements as well as more computational approaches to explore the temporal, genetic, and anatomical components involved in grafting. We inferred gene regulatory networks for compatible self-grafts versus incompatible heterografts and predicted core regulators for grafting. We then examined the role of vascular development in graft formation and validated SlWOX4 as a regulator for grafting in tomato. Finally, we studied how graft compatibility influences cell death, by utilizing viability stains and programmed cell death indicators. We were able to show that programmed cell death is present in all graft junctions, but that the driving cause for cell death in this incompatible combination is acute stress-induced necrosis. This work has explored the symptoms, causes, and taxonomic limits of graft compatibility. We have identified novel genes involved in grafting and identified a role for necrosis in graft-incompatibility, further elucidating the mechanisms that underlie plant grafting.

Purpose The decreasing number of peatlands has driven the search for new cultivation substrates. The aim of this study was to evaluate the use of different composts as growing media in the production of vegetable seedlings (pepper and tomato). Method Composts were produced from: discarded carrots (ZC), fats (FC), and biosolids (BC) from the dairy industry. They were used as peat substitutes in different doses depending on the germinating species: control (CS-commercial substrate) and three growing media prepared with perlite: 25, 35, and 45% of ZC, FC, and BC for pepper seedlings and 40, 55 and 70% of ZC, FC, and BC for tomato seedlings. When the plants were ready for transplantation they were harvested and the data were collected to assess the development of the seedlings in the different growth media. Results The obtained results suggest the possibility of total substitution of the CS by ZC, FC, and BC to produce pepper and tomato plants in commercial nurseries. The plants cultivated with composts presented higher concentrations of total dry matter compared to the controls. Photosynthetic pigments were affected by the presence of FC and BC, whereas TSP concentration was favored by BC. Conclusion Ours results suggest that it is feasible to perform a total substitution of commercial substrates with composts of different origins and compositions for the production of pepper and tomato plants in commercial nurseries.

Phytophthora blight, caused by the oomycete pathogen Phytophthora capsici, is a devastating disease of various vegetable crops, including squash (Cucurbita pepo) and pepper (Capsicum annuum). Options for host resistance to Phytophthora blight vary dramatically between these two crops. In squash, no sources of complete resistance have been described, although variation for quantitative disease resistance exists in both commercial and unadapted germplasm. In pepper, on the other hand, landraces demonstrating complete or near-complete disease resistance have been identified and used in breeding. However, varieties with durable resistance to diverse pathogen isolates have not been developed. In order to contribute to genetic solutions for disease control in these two crops, genetic variation in squash associated with quantitative disease resistance as well as genetic variation in P. capsici associated with virulence on distinct pepper genotypes were characterized. In squash, two quantitative trait locus (QTL) mapping approaches were used in a zucchini _ gray zucchini population, resulting in the discovery of six QTL, representing the first reported for Phytophthora blight resistance in C. pepo. In order to identify genetic variants in P. capsici associated with virulence on pepper, a collection of 252 pathogen isolates, predominantly from vegetable production regions of New York state, was genotyped at over 100,000 single-nucleotide polymorphism (SNP) loci using genotyping-by-sequencing. The utility of this isolate collection as a genetic resource was demonstrated by the successful identification of SNPs associated with mating type and sensitivity to the fungicide mefenoxam via a genome-wide association study (GWAS). Inoculation of 117 genetically distinct isolates onto a panel of 16 pepper accessions revealed a significant effect of inter-species genotype-genotype interactions on disease outcomes. However, the only SNP associated with virulence in a GWAS demonstrated an effect that was consistent across pepper genotypes, suggesting that genes involved in host-specific virulence may be of smaller effect and more challenging to map. The results of these genetic experiments – conducted on both pathogen and host – are expected to inform efforts to breed vegetable crops with durable Phytophthora blight resistance.

This paper traces the history of the pepper trade between Salem, Massachusetts, and the island of Sumatra. It attempts to fill the gap in historical knowledge of America’s early relations with Southeast Asia prior to its colonization of the Philippines in 1899, and covers the period from 1799 to 1846. The paper also discusses the implications that trade with Southeast Asian polities had on American foreign policy in the early period. The paper argues as well that American merchants’ arrival in the East Indies represented the weakening of the Dutch East India Company’s monopoly on the spice trade in Southeast Asia, which eventually ended in the company’s bankruptcy, the takeover of the East Indies colony by the Dutch crown, and a permanent change in Dutch policy that emphasized territorial conquest as a means of securing Dutch control over the archipelago.

Less-lethal weapons have been effective at saving lives by providing police an option for defense or apprehension that does not involve a firearm. However, not all less-lethal weapons are created equal, and careful planning with a solid base of research must be done to insure that officers are prepared for every circumstance. The purpose of this study is to analyze the current information about less-lethal weapons and create a comprehensive breakdown of their strengths and weaknesses. This will include current statistics on the most common less-lethal weapons, as well as insight from scholarly sources. The strengths and weaknesses of a less-lethal weapon can be analyzed with the categories of lethality, or how often the weapon kills or seriously injures, and how often it is effective at ending an altercation. Each weapon will be examined in light of these categories, as well as any other merits or demerits that may arise. In addition, this study showcases how police can be trained, emphasizing either citizen safety or officer safety, and offers suggestions to implement in the future. Ideally this study can be used as a tool for law enforcement agencies and officers to be better equipped for their profession.

A total of 21 (poly)phenolic compounds (free and bound) were quantified in raw, olive oil fried, sunflower oil fried and griddled green pepper before and after a simulated gastrointestinal digestion. Flavonoids, particularly quercetin rhamnoside, were the main compounds. The bioaccessibility of (poly)phenolic compounds after gastrointestinal digestion was higher in cooked (>82%) than in raw (48%) samples, showing a positive effect of heat treatment on the release of (poly)phenols from the vegetal matrix. Additionally, a faecal fermentation was carried out for 24h. A time-dependent microbial metabolic activity was observed, which resulted firstly (

Phytophthora capsici is a destructive oomycete pathogen of many vegetables, causing root, crown, and fruit rot, as well as foliar disease. Host resistance is an important management strategy in pepper, and the high levels of diversity in field populations of P. capsici have important implications for screening and selecting resistant cultivars. In order to better understand the changing structure of a field population, a previously-uninfested research field was inoculated with two single-spore isolates of P. capsici in September 2008. Isolates from this field were collected over the following four years and characterized with five microsatellite markers. A sexual population was established in the field, characterized by high genotypic diversity and no evidence of genetic drift. In addition, four novel alleles were detected, and characterization of F1 progeny from an in vitro cross between the same two parental isolates revealed evidence of non-Mendelian inheritance of alleles. In order to provide practical information to New York vegetable growers, commercial bell pepper cultivars were screened for resistance to P. capsici using a representative local isolate, over five years. In one year, yield and fruit quality were compared among commercial cultivars at three sites (one inoculated with P. capsici and two uninoculated). The cultivars Aristotle, Intruder, and Paladin were consistently most resistant to the isolate used, and while total marketable yields were comparable among resistant and susceptible cultivars, these more resistant cultivars tended to have smaller fruit and more problems with silvering than the susceptible cultivars. In order to better understand the P. capsici-pepper pathosystem, interactions between a P. capsici isolate (PcapG-a) tagged with green fluorescent protein and susceptible or resistant pepper cultivars were studied. Surprisingly, P. capsici zoospores attached to and germinated equally well on roots of resistant and susceptible cultivars within 120 minutes of inoculation. Differences in pathogen colonization of roots and crowns of resistant and susceptible cultivars were observed 3 days post inoculation. Although previous studies have implicated upregulation of plant defense genes in pepper host resistance to P. capsici, we did not see evidence of this at 8 or 24 hours post inoculation in either pepper stem or leaf tissue.

The effective dispersal ability of the egg parasitoid Trichogramma ostriniae Pang and Chen was assessed in potato fields on the Eastern Shore of Virginia in spring 2005 and 2006. Approximately 0.5 million T. ostriniae were released from a central release point in separate potato fields. Dispersal was monitored using yellow sticky card traps and European corn borer, Ostrinia nubilalis Hübner, egg mass sentinels. Adult T. ostriniae dispersed quickly throughout the 0.4 ha (1 acre) sampling area. Parasitism and sticky card captures were highest close to the release point and decreased with increasing distance. Sticky card data were a good fit to the diffusion model used (r² > 0.90) for all but two sampling dates. In 2005 parasitization peaked at 4 days post release with close to 40% of sentinels parasitized at 30m from the release point. The mean distance encompassing 98% (x98) of T. ostriniae for both fields in 2005 was 27.5 (± 2.4) meters. For fields 1 and 2 in 2005, x98 for parasitism was 21 and 26 meters, respectively. In 2006 sticky card data fit the dispersal model moderately well (r² > 0.77) except for two sampling dates and dispersal was generally lower. The mean x98 value for sticky card data was 12.9 (± 0.9) meters. For parasitism, the x98 distances for field 1 and 2 were estimated at 8 and 10 meters, respectively. Correlation analysis showed no significant difference in the distributions between sticky card captures and sentinel egg mass parasitism. In 2006, T. ostriniae were released in small pepper plots in Pennsylvania, Maryland and two locations in Virginia to evaluate the number of wasps needed per plant for effective control of European corn borer. Treatments included 0, 5, 20 and 50 wasps per plant. In each plot, parasitism was measured using 30 sentinel egg masses collected on 3 and 6 days post release. Parasitism was relatively low in Pennsylvania and Virginia and no significant effect from release density was observed. High rates of parasitization in the untreated control plot were observed in Maryland as well as one of the Virginia locations. Overall results show results show ambiguity in the data and high levels of natural parasitism occurring on Ephestia eggs sentinels. In 2005 and 2006, several insecticides were evaluated for controlling O. nubilalis and impacting arthropod natural enemies in bell pepper. In addition, we compared the effectiveness of an integrated pest management program based around inundative releases of T. ostriniae to a conventional insecticide-based program for O. nubilalis control in multiple locations in the Mid- Atlantic US. To evaluate the insecticides, small plots of bell pepper were established at four locations in Virginia, Maryland, Delaware, and Pennsylvania. Insecticides were applied weekly from first fruit until final harvest (5 to 7 applications). Results indicated that the biorational insecticides, spinosad, indoxacarb, and methoxyfenozide provided comparable control of O. nubilalis as the broadspectrum conventional insecticides, acephate, and lambda-cyhalothrin. At most locations, multiple sprays of lambda-cyhalothrin resulted in flares (outbreaks) of green peach aphids most likely from destruction of arthropod natural enemies. Indoxacarb also caused a similar aphid flare at one of the locations. For the IPM demonstration experiment, pepper plots were established at 5 locations in the Mid-Atlantic U.S. in 2005 and 2006. Treatments included: "conventional", which involved weekly applications of acephate or lambda-cyhalothrin from first fruit until final harvest; 2) "IPM", which included three or four inundative releases of T. ostriniae and a judicial application of methoxyfenozide only if lepidopteran pests exceeded action thresholds; and 3) an untreated control. No significant treatment effect was found in either year on cumulative number of marketable fruit or percentage of fruit damaged by lepidopteran pests. A significant treatment effect was found on peak numbers of green peach aphids, with the conventional insecticide approach causing aphid flares and the untreated control or IPM approach not having aphid pest problems. Inundative releases of T. ostriniae may be a more environmentally-sound approach to managing O. nubilalis in peppers, although a comparison with conventional insecticides under greater lepidopteran pest pressure is still needed.

Four to six separate inundative releases of ~30,000 to 50,000 T. ostriniae per 0.02 ha significantly reduced damage by O. nubilalis in bell pepper. Egg parasitization averaged 48.7% in T. ostriniae release plots, which was significantly higher than non-release plots (1.9%). Also, cumulative green pepper fruit damage averaged 8.7% in release plots, which was significantly less than non-release plots (27.3%). Pesticides tested against T. ostriniae were spinosad and methoxyfenozide. Spinosad adversely affected adult T. ostriniae producing 100% mortality at the field rate of 498 mg [AI]/L for both the preimaginal and adult toxicity tests. Use of T. ostriniae can provide effective control of O. nubilalis in pepper compared to conventional and organic spray regimes (Spinosad and methoxyfenozide respectively). Augmentative releases of T. ostriniae integrated with methoxyfenozide with its limited toxicity to both preimaginal and adult stages indicate that it is a superior candidate for control O. nubilalis. To determine the behavioral differences of T. ostriniae and its response to O. nubilalis in green bell peppers, experiments were carried out to classify likely areas of O. nubilalis oviposition within the green pepper plant canopy. A total of 426 O. nubilalis egg masses were found on pepper plants during our study. Over 92% of egg masses were found on the lower surface of the leaf compared with the upper surface indicating a significant ovipositional preference for the undersides of leaves in 2002 ( x2 = 9.68; df = 1; P < 0.05) followed by similar results in 2004 (x2 = 4.34; df = 1; P < 0.05). No significant differences were found in the observed spatial distribution of egg masses among the three vertical strata in either 2002 or 2004 (x2 = 1.75; df = 2; P < 0.05 and x2 = 5.69; df = 2; P < 0.05 respectively). Field release rates of 17.0 foraging T. ostriniae females can achieve 80.0% parasitism of O. nubilalis egg masses distributed throughout the pepper plant canopy found primarily on the undersides of leaves. These data demonstrate that T. ostriniae has potential as a biocontrol agent for O. nubilalis in solanaceous crops.

Anthracnose (caused by Colletotrichum capsici or C. gloeosporioides) of bell peppers (Capsicum annum) has become a serious problem in recent years on the Eastern Shore of Virginia. The purpose of this research was to characterize isolates of the fungus from the Eastern United States, to compare them with the type species from the American Type Culture Collection, and to evaluate fungicides for disease management. Two cultivars of pepper were inoculated with a conidial suspension, and held in a dew chamber. Lesions were counted and measured every 48 hours. The type species was either not pathogenic or only mildly virulent; most of the virulent isolates originated in areas of intensive pepper production. In addition to pathogenicity experiments and traditional morphology, the Biolog® system was used to compare the ability of fungi to utilize different carbohydrate combinations in 96-well plates. Plates were read at 96 and 168 hours. Analysis of data, by Ward's statistical method, could reliably distinguish field isolates if based on 15 or more replications, but species-level identification was inconsistent. Standard fungicides and new compounds were compared in a field test with four replications of treatments in a randomized complete block design. Fruits were harvested three times, weighed for yield, and the number of marketable and diseased fruit recorded. Aggressive isolates from green pepper were controlled by applications of maneb, or alternation of maneb and strobilurin fungicides.

Strains with mutations in the avrBs2 locus of Xanthomonas axonopodis (syn. campestris) pv. vesicatoria, which causes bacterial spot in pepper (Capsicum spp.), were detected and caused disease in pepper containing the Bs2 resistance gene. Aggressiveness and competitiveness of the mutant strains was evaluated under laboratory and field conditions. Three strains each of races 3, 4, and 6 were separately inoculated on susceptible pepper plants (cv. Camelot) in field plots with one race/plot. Inoculum naturally spread within plots to bordering rows of pepper plants of ECW (bs2/bs2) or ECW-20R (Bs2/Bs2). A specific strain within each race predominated on either ECW or ECW-20R plants. Races 3 (functional avrBs2) and 6 (non-functional avrBs2) had similar AUDPC values, and caused similar disease severity on ECW plants. Races 4 (non-functional avrBs2, but functional avrBs3) and 6, which defeat the Bs2 gene caused severe disease on ECW-20R, but severity was less compared to pepper plants of ECW lacking the Bs2 gene. Frequency of recovery of strains in field plots was associated with bacterial multiplication and lesion efficiency results in the laboratory. Although, expression of the non-functional avrBs2 gene in strains of races 4 and 6 was detected, AvrBs2 protein translation may not occur or be in an inactive form as indicated by no hypersensitive reaction (HR) and disease in plants carrying the Bs2 resistance gene. Loss of avrBs2 activity apparently results in less fitness cost in race 6 than in race 4 strains; however, there is variability in competitiveness among strains within races. Mutations in the 5-bp short-sequence repeat region of the avirulence gene avrBs2 were detected in field strains that defeat the Bs2 gene. The avrBs2 has both avirulence and virulence activities. We hypothesized that if the avrBs2 gene is required for full virulence and fitness of Xav, in the absence of selection pressure by the Bs2 resistance gene, functional avrBs2 should be favored. Seven strains representing races 4, 5, and 6 with 5-bp mutations (5-bp addition and 5-bp deletion) and resistant to rifampicin were tested for the potential to switch from non-functional to functional avrBs2. This hypothesis was tested in the laboratory using broth cultures and potted pepper plants and in a field experiment. No strains with functional avrBs2 were detected in the laboratory experiments. Although 3 (0.15%) of 1,961 colonies from the field experiment had functional avrBs2, these strains did not result in a detectable population shift. This suggests that the selection pressure for functional avrBs2 in the absence of resistance gene Bs2 is weak or absent. Results presents here indicate that pathogen strains with loss of avirulence gene functions (i.e., fail to elicit an HR) can be less aggressive under field conditions and that competitiveness varies among strains. However, such strains retain the ability to cause significant, unacceptable disease loss if no other controls are used. Studies have shown that aggressiveness is not the only factor contributing to pathogenic fitness. Other avr genes or other genes and environmental factors may contribute to overall pathogenic fitness.

Weed management programs in "Superior" potato with PRE and POST rimsulfuron treatments were investigated during 1992, 1993, and 1994. Common ragweed control by PRE combinations of metolachlor with linuron or metribuzin was higher when treatments included PRE or POST rimsulfuron. Common lambsquarters control was 93 to 96% by treatments that included POST rimsulfuron. Applications of 35 g ai/ha rimsulfuron plus 280 g ai/ha metribuzin POST controlled weeds comparable to sequential applications. Potato recovered from occasional injury caused by rimsulfuron, rimsulfuron plus metribuzin, and organophosphate insecticides combined POST with rimsulfuron plus metribuzin. Several acetolactate synthase (ALS)-inhibiting herbicides were evaluated for yellow nutsedge control in the greenhouse. Herbicides were applied POST to yellow nutsedge at actual or anticipated commercial rates. Yellow nutsedge control was 92 and 71% from halosulfuron and chlorimuron, respectively. Control ranged from 48 to 69% from primisulfuron, pyrithiobac, and rimsulfuron. Control from nicosulfuron and imazethapyr was 45 and 68%, respectively, while thifensulfuron and CGA-152005 had almost no activity on yellow nutsedge. Chlorimuron, imazethapyr, and halosulfuron were the only herbicides which reduced yellow nutsedge regrowth. Rrimsulfuron was evaluated in tomato at 26 and 35 g ai/ha, sequentially at 26 g/ha, at 26 g/ha plus metribuzin at 280 g ai/ha, and metribuzin at 280 g/ha were evaluated POST for weed control in transplanted "Agriset" tomato. Common lambsquarters was controlled by rimsulfuron at 35 g/ha. Rimsulfuron plus metribuzin gave consistent control of common ragweed but jimsonweed and goosegrass control was generally low. Rimsulfuron treatments caused < 12% injury to tomato. Tomato yield was consistently high in the metribuzin, metribuzin plus rimsulfuron, and rimsulfuron sequential treatments. In greenhouse studies, giant foxtail and large crabgrass control by rimsulfuron was above 95 and 85% respectively, but goosegrass was not controlled. Height of four tomato cultivars was not reduced, but dry weight of "Floradade" and "Sunbeam" was reduced by rimsulfuron. In 1993, 1994 and 1995, PPI clomazone at 390 g ai/ha, POST rimsulfuron at 35 g ai/ha, and PPI trifluralin at 560 g ai/ha were evaluated for weed control in transplanted "Keystone RG3" bell pepper. Common lambsquarters and jimsonweed control was highest by clomazone treatments, while common ragweed control was low from all treatments. Keystone RG3 in the field and greenhouse and "Camelot," "Jupiter" and "Memphis" in the greenhouse were injured by POST rimsulfuron and had lower height and dry weight than untreated controls. In the greenhouse, black nightshade control was below 23% and jimsonweed control was below 49% by rimsulfuron POST. The absorption, translocation, and metabolism of rimsulfuron was investigated in three Solanaceous weed species. Rimsulfuron uptake did not differ between black nightshade and eastern black nightshade while less labeled herbicide was absorbed by hairy nightshade. Black and eastern black nightshade translocated up to 50% of the labeled herbicide out of the treated leaf with 40 to 50% of the herbicide being moved to the actively growing regions of the plant. In hairy nightshade, an average 40% of the labeled herbicide was moved out of the treated leaf and less than 30% of the translocated herbicide was moved basipetally. Most major metabolites were apparent at 24 and 48 hours however, there were no differences in metabolite composition. Rimsulfuron will be an effective herbicide for use in weed management programs in potato and tomato, however rimsulfuron causes too much injury in pepper to be used.