Annuum Cultivars Research Articles

Comparative transcriptome analysis and Arabidopsis thaliana overexpression reveal key genes associated with cadmium transport and distribution in root of two Capsicum annuum cultivars

The molecular mechanisms underlying high and low cadmium (Cd) accumulation in hot pepper cultivars remain unclear. In this study, comparative transcriptome analysis of root between high-Cd (J) and low-Cd (Z) cultivars was conducted under hydroponic cultivation with 0 and 0.4 mg/L Cd, respectively. The results showed that J enhanced the root uptake of Cd by elevating the expression of Nramp5 and counteracting Cd toxicity by increasing the expression of genes, such as NIR1, GLN1, and IAA9. Z reduced Cd accumulation by enhancing the cell wall lignin synthesis genes PAL, COMT, 4CL, LAC, and POD and the Cd transporters ABC, MTP1, and DTX1. Elevated expression of genes related to sulfur metabolism was observed in Z, potentially contributing to its ability to detoxify Cd. To investigate the function of CaCOMT1, an Arabidopsis thaliana overexpression line (OE-CaCOMT1) was constructed. The results revealed that OE-CaCOMT1 drastically increased the lignin content by 38–42% and reduced the translocation of Cd to the aboveground parts by 32%. This study provides comprehensive insights into the mechanisms underlying Cd accumulation in hot pepper cultivars using transcriptome analysis. Moreover, this study elucidates the critical function of CaCOMT1, providing a theoretical foundation for the production of low-Cd vegetables for food safety.

Harnessing CRISPR/Cas9 for Enhanced Disease Resistance in Hot Peppers: A Comparative Study on CaMLO2-Gene-Editing Efficiency across Six Cultivars

The Capsicum annuum Mildew Locus O (CaMLO2) gene is vital for plant defense responses against fungal pathogens like powdery mildew, a significant threat to greenhouse pepper crops. Recent advancements in genome editing, particularly using clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9, have unlocked unprecedented opportunities for modifying disease-resistant genes and improving crop characteristics. However, the application of CRISPR technology in pepper cultivars has been limited, and the regeneration process remains challenging. This study addresses these limitations by investigating the feasibility of using the validated CaMLO2 genetic scissors system in six commercial hot pepper cultivars. We assessed the gene-editing efficiency of the previously reported high-efficiency Cas9/CaMLO2single-guide RNA (sgRNA)1-ribonucleoprotein (RNP) and the low-efficiency Cas9/CaMLO2sgRNA2-RNP systems by extending their application from the bell pepper ‘Dempsey’ and the hot pepper ‘CM334’ to six commercial hot pepper cultivars. Across the six cultivars, CaMLO2sgRNA1 demonstrated an editing efficiency ranging from 6.3 to 17.7%, whereas CaMLO2sgRNA2 exhibited no editing efficiency, highlighting the superior efficacy of sgRNA1. These findings indicate the potential of utilizing the verified Cas9/CaMLO2sgRNA1-RNP system to achieve efficient gene editing at the CaMLO2 locus in different Capsicum annuum cultivars regardless of their cultivar genotypes. This study provides an efficacious genome-editing tool for developing improved pepper cultivars with CaMLO2-mediated enhanced disease resistance.

Untargeted Phytochemical Profiling, Antioxidant, and Antimicrobial Activities of a Tunisian Capsicum annuum Cultivar.

Peppers are among the spices possessing a wide plethora of biological properties due to their excellent supply of health-related metabolites. Capsicum annuum L. (Solanaceae) is cultivated throughout Tunisia, and there is a shortage of information on the identification of the secondary metabolites in the seeds of this species as well as on their biological activities. In the present work, we intended to undertake a chemical characterization of the bioactive compounds from the hydro-methanolic seed extract of C. annuum as well as an evaluation of its broad spectrum of antimicrobial and antioxidant activities. The chemical profile was evaluated by RP-HPLC-DAD-QTOF-MS/MS, whereas the total phenol and flavonoid content, antioxidant, and antimicrobial activities were determined in in vitro assays. In this work, 45 compounds belonging to various phytochemical classes, such as organic acids (2), phenolic compounds (4 phenolic acids and 5 flavonoids), capsaicinoids (3), capsianosides (5), fatty acids (13), amino acids (1), sphingolipids (10), and steroids (2) were identified in the hydro-methanolic seed extract of C. annuum. The phenolic and flavonoid content (193.7 mg GAE/g DW and 25.1 mg QE/g DW, respectively) of the C. annuum extract correlated with the high antiradical activity (IC50 = 45.0 µg/mL), reducing power (EC50 = 61.3 µg/mL) and chelating power (IC50 = 79.0 µg/mL) activities. The hydro-methanolic seed extract showed an important antimicrobial activity against seven bacterial and four fungal strains. In fact, the inhibition zones (IZs) for bacteria ranged from 9.00 ± 1.00 mm to 12.00 ± 0.00 mm; for fungi, the IZs ranged from 12.66 ± 0.57 mm to 13.66 ± 0.57 mm. The minimal inhibition concentration and minimal bactericidal concentration values showed that the extract was more effective against fungi than bacteria.

Antocyanidin-3-<i>O</i>-Glucosyltransferase Genes in Pepper (<i>Capsicum</i> spp.) and Their Role in Anthocyanine Biosynthesis

In pepper (Capsicum spp.), anthocyanins are important not only for the photolabile compounds protection, but also for the regulation of fruit color pattern. Anthocyanidin-3-O-glucosyltransferases (UFGTs) play a key role in the biosynthesis of stable anthocyanins. In this work, the structure and phylogeny of three pepper UFGT homologue genes are characterized. Biochemical analysis of C. annuum cultivars (cv. Syrenevii cube, Othello and Sibiryak) and C. frutescens (cv. Samotsvet), which differ in the pattern of fruit pigmentation during ripening, showed the presence of anthocyanins in leaves and fruit peel of all accessions (except for the cv. Sibiryak fruit). The highest anthocyanins content was found in the purple leaves of the cv. Samotsvet. In the fruit peel of all accessions, the anthocyanins content decreased with ripening. Expression analysis of the same tissues showed that UFGT1 (LOC107843659) and UFGT2 (LOC107843660) transcripts are present in the leaves of all cultivars. In the fruit peel, UFGT1 transcripts were detected at maturation stages 1 (cv. Syrenevii cube and Othello) and 1–3 (cv. Samotsvet), while UFGT2 transcripts were found in all accessions with the maximum in the cv. Sibiryak, where anthocyanins were absent. Transcripts of the MBW complex (anthocyanin2, MYC, and WD40), which regulates the biosynthesis of anthocyanins, were present in the leaves of all cultivars with a maximum in the purple leaves of the cv. Samotsvet. Comparison of biochemical and expression data revealed a positive correlation between the amount of anthocyanins in fruit peel and leaves and UFGT1 expression level. For UFGT2 such correlation was no found. Analysis of UFGT1 sequence, including the promoter region, in 18 pepper cultivars that differ in fruit color pattern, revealed sequence invariance, regardless of the color of the immature fruit. Analysis of the UFGT1 and UFGT2 promoter sequences of the showed differences in the composition of cis-regulatory elements involved in response to stress and hormones, and in MYB and MYC transcription factors binding sites.

Indicator Candidate Traits for Autonomous Fruit Set Ability Under High Temperatures in Capsicum

Abstract “Autonomous fruit set” refers to self-pollination and fruit set without pollen vectors such as vibration or insects. Autonomous fruit set under high-temperature stress is an important breeding goal as climate change can reduce fruit yields in Capsicum. We screened Capsicum cultivars for autonomous fruit set ability in a greenhouse environment and investigated pollen germination, viability, pollen grains number, chlorophyll fluorescence (Fv/Fm), style length, anther cone length, and anthesis stage under high temperatures in order to identify indicator traits for screening more genotypes with autonomous fruit set ability. The fruit set of the ‘Takanotsume’ (57.7 ± 20.6%) and ‘Goshiki Kyokko’ (52.2 ± 14.2%) cultivars (both C. annuum) were higher than those of other cultivars. Correlation analysis showed that pollen germination had the highest correlation with fruit set in C. annuum cultivars (r = 0.63). These results indicate that ‘Takanotsume’ and ‘Goshiki Kyokko’ are useful cultivars for novel breeding programs focusing on autonomous fruit sets under high temperatures, and pollen germination in C. annuum was a convincing candidate for an indicator trait of autonomous fruit set ability under high temperatures.

Effects of Interspecific Grafting Between Capsicum Species on Scion Fruit Quality Characteristics

Production of Capsicum annuum peppers is often limited, especially in tropical environments, by susceptibility to soil pathogens including Ralstonia solanacearum. Grafting desirable cultivars onto selected rootstocks can increase adaptation to abiotic stress and is an alternative to pesticides for managing soilborne pathogens. Cultivars of two other pepper species, Capsicum baccatum and Capsicum chinense, are tolerant or resistant to an array of soilborne pathogens and have potential as rootstocks; however, knowledge of how interspecific grafting may affect scion fruit quality is lacking. Flowering time, yield, and fruit quality characteristics were evaluated in 2017 and 2020 for C. annuum cultivars Dulcitico, Nathalie (2017), Gypsy (2020), and California Wonder used as scions grafted onto Aji Rico (C. baccatum) and Primero Red (C. chinense) rootstocks, including self-grafted and nongrafted scion checks. In 2020, the rootstocks per se were evaluated. The two rootstocks (‘Aji Rico’ and ‘Primero Red’), three scions, and self- and nongrafted scions were evaluated using a factorial, replicated, completely randomized design in fields at the West Madison and Eagle Heights Agricultural Research Stations located in Madison, WI, in 2017 and 2020, respectively. Differences among the main effects for scion fruit quality characteristics were consistent with cultivar descriptions. No scion × rootstock interactions were observed. Rootstocks did not result in changes in total fruit number, yield, fruit shape (length-to-width ratio), or soluble solids of scion fruit compared with self- and nongrafted checks. The rootstock ‘Primero Red’ increased fruit weight and decreased time to flowering regardless of scion compared with self- and nongrafted checks. All scions were sweet (nonpungent) cultivars and both rootstocks were pungent cultivars. No capsaicinoids were detected in the fruit of sweet pepper scions grafted onto pungent pepper rootstocks. The results indicate that interspecific grafts involving ‘Aji Rico’ and ‘Primero Red’ will not have deleterious effects on fruit quality characteristics of sweet pepper scions.

Evaluation of the antioxidant potential of Capsicum annuum L., C. baccatum L. and C. chinense Jacq. cultivars.

Economically important vegetables are a strong source of antioxidants with different characteristics. Capsicum L. (pepper) is an important agricultural plant because of its economical, medicinal, and nutritional values. This study aimed to test antioxidant parameters in the fruits of 9 cultivars of Capsicum annuum L. (CA 01-09), 7 cultivars of C. baccatum L. (CB 01-07), and 11 cultivars of C. chinense Jacq. (CC 01-11). The antioxidant activity of the investigated Capsicum cultivars was measured, along with the free radical scavenging activity (FRSA), using the DPPH method, and the molybdenum reducing power (MRP) was expressed as mg TE (Trolox equivalent) per g of DW (dry weight). Total polyphenol content (TPC), expressed as mg GAE (gallic acid equivalent) per g of DW, total flavonoid content (TFC), expressed as mg QE (quercetin equivalent) per g of DW, and total phenolic acid content (TPAC), expressed as mg CAE (caffeic acid equivalent) per g of DW, were the basic antioxidant parameters of antioxidant activity in this study. All investigated Capsicum extracts exhibited FRSA from 1.45 (CC-06) to 8.21 (CC-05) mg TE/g and MRP from 24.84 (CA-06) to 198.21 (CB-07) mg TE/g. The TPC of the tested extracts ranged from 10.13 (CB-03) to 38.68 (CB-07) mg GAE/g. The TFC of the studied samples showed values from 5.73 (CB-03) to 27.32 (CB-07) mg QE/g and TPAC from 2.24 (CB-03) to 13.07 (CC-07) mg CAE/g. A very strong correlation was found in the investigated cultivars between TPC and TPAC (r = 0.932, 0.839 and 0.848, respectively), and between TPC and TFC (r = 0.921, 0.982 and 0.939, respectively). Very strong relations were also found between TPC and FRSA (r = 0.820) in the C. annuum cultivars and between TPC and MRP (r = 0.898) in the C. baccatum cultivars. This study found useful results concerning the antioxidant potential of the fruits of Capsicum cultivars. The data obtained demonstrate the strong antioxidant activity of cultivars of Capsicum, which can be used in the food industry because of the commercial importance of these fruits.

Genetic diversity and morphological responses of Capsicum annuum varieties under aluminum stress

Abstract. Andriyani, Jadid N. 2021. Genetic diversity and morphological responses of Capsicum annuum varieties under aluminum stress. Biodiversitas 22: 2576-2582. Capsicum annuum is one of the most cultivated vegetable crops in the world. Its fruit contains various beneficial metabolites which possess antioxidant activities. Fertilizers play important role to increase plant productivity. However, excessive use of fertilizers could harm the environment. Heavy metals, including aluminum (Al), contamination have been reported to negatively affect plant production and inhibit root growth. C. annuum var Ciko, Lingga, Lembang1, and Tanjung2 are commonly cultivated in Indonesia. However, the genetic diversity of those plants and their responses to Al stress condition are still unknown. Therefore, our study aimed to analyze the genetic diversity of four C. annuum cultivars and to observe their morphological responses under Al stress conditions. The genetic diversity was analyzed using five universal inter-simple sequence repeat (ISSR) primers. Our results showed that the PIC values ranged from 0 (primer 825) to 0.6375 (Primer 9). The UPGMA phylogenetic construction also demonstrated that the cv. Lembang1 is closely related to the cv Lingga. Meanwhile, cv Tanjung 2 is closely related to the cv. Ciko. Each cultivar also performed different morphological responses under Al stress conditions. Our data showed that Al affected significantly root growth but not affected their plant height. Aluminum at 100 ppm significantly decreased root length of cv. Lingga

Structural and functional features of phytoene synthase isoforms PSY1 and PSY2 in pepper Capsicum annuum L. cultivars.

The fruits of various pepper cultivars are characterized by a different color, which is determined by the pigment ratio; carotenoids dominate in ripe fruits, while chlorophylls, in immature fruits. A key regulator of carotenoid biosynthesis is the phytoene synthase encoded by the PSY gene. The Capsicum annuum genome contains two isoforms of this enzyme, localized in leaf (PSY2) and fruit (PSY1) plastids. In this work, the complete PSY1 and PSY2 genes were identified in nine C. annuum cultivars, which differ in ripe fruit color. PSY1 and PSY2 sequence variability was 2.43 % (69 SNPs) and 1.21 % (36 SNPs). The most variable were PSY1 proteins of the cultivars ‘Maria’ (red-fruited) and ‘Sladkij shokolad’ (red-brown-fruited). All identified PSY1 and PSY2 homologs contained the phytoene synthase domain HH-IPPS and the transit peptide. In the PSY1 and PSY2 HH-IPPS domains, functionally significant sites were determined. For all accessions studied, the active sites (YAKTF and RAYV), aspartate-rich substrate-Mg2+-binding sites (DELVD and DVGED), and other functional residues were shown to be conserved. Transit peptides were more variable, and their similarity in the PSY1 and PSY2 proteins did not exceed 78.68 %. According to the biochemical data obtained, the largest amounts of chlorophylls and carotenoids across the cultivars studied were detected in immature and ripe fruits of the cv. ‘Sladkij shokolad’ and ‘Shokoladnyj’. Also, ripe fruits of the cv. ‘Nesozrevayuschij’ (green-fruited) were marked by significant chlorophyll content, but a minimum of carotenoids. The PSY1 and PSY2 expression patterns were determined in the fruit pericarp at three ripening stages in ‘Zheltyj buket’, ‘Sladkij shokolad’, ‘Karmin’ and ‘Nesozrevayuschij’, which have different ripe fruit colors: yellow, red-brown, dark red and green, respectively. In the leaves of the cultivars studied, PSY1 expression levels varied significantly. All cultivars were characterized by increased PSY1 transcription as the fruit ripened; the maximum transcription level was found in the ripe fruit of ‘Sladkij shokolad’, and the lowest, in ‘Nesozrevayuschij’. PSY2 transcripts were detected not only in the leaves and immature fruits, but also in ripe fruits. Assessment of a possible correlation of PSY1 and PSY2 transcription with carotenoid and chlorophyll content revealed a direct relationship between PSY1 expression level and carotenoid pigmentation during fruit ripening. It has been suggested that the absence of a typical pericarp pigmentation pattern in ‘Nesozrevayuschij’ may be associated with impaired chromoplast formation.

Unravelling the genetic diversity and phylogenetic relationships of Indian Capsicum through fluorescent banding

Hot chilli species of Capsicum are one of the most significant spice crops in India having several genetically distinct cultivars. The present study was targeted to upgrade chromosomal database of 15 cultivars belonging to C. annuum L., C. frutescens L. and C. chinense Jacq. EMA-based fluorochrome banding with GC-specific stain Chromomycin A3 (CMA) was elemental to reveal specialization in karyotypes that could not be traced out by Giemsa-stained preparations. CMA banding pattern was combined with karyomorphometric indices to statistically evaluate chromosomal relationship among the cultivars. The marker chromosome pairs 11 and 12 containing nucleolar CMA bands could be suggested as the evolutionary landmarks in ‘C. annuum complex’. We found direct correspondence between fruit morphotype variation and CMA banding pattern to demonstrate maximum genetic diversity within C. annuum, followed by C. frutescens while Bhut jolokia of C. chinense displayed genetic uniformity. UPGMA phenogram upheld distinct species separation, cultivar diversity and relationships within and among the species. Out of nine C. annuum cultivars, at least two cultivars showed some sort of genetic relationship with C. chinense, particularly the Ghee cultivar shares more proximity with C. chinense. The fluorescent karyotype database reliably symbolized uniqueness of Capsicum germplasm of India, especially from the NEH sector that grows Bhut jolokia. Our attempt is believed to complement genomic investigation in the popular and exotic chilli cultivars of India and interest breeders in search of alternative genetic resources.

Change in Iodine Contents during Ripening of two <i>Capsicum annuum L.</i> Cultivars Fruits at Brazzaville, CONGO

To identity iodine, assessits concentration and analyse the variation of this concentration following the ripeness stages, its titrating from Capsicum annuum L. dried fruit extract by sodium thiosulfate and starch solution test were achieved. Small and big Capsicum annuum cultivars were planted according to completely randomised design onto eight rows with eight seedlings whose four was useful. One-factor Anova incorporating the means comparison according to Student-Newman-Keuls’ test at 5% level was applied. Likewise, Pearson’s linear correlation at 1‰00 probability was used. Results shown that small and big Capsicum annuum L. cultivars contained iodine. People should consum Capsicum annuum L. fruits to avoid goiter. Other animal and plant foods also contain iodine. Iodine concentration discriminated the fruit ripeness stages in small Capsicum annuum L. cultivar. At the pre-ripeness stage (PMG), iodine concentration was higher than the ripe one (MG). Consequently, the consumption of its fruits is recommended at pre-ripeness stage to optimise the ingesting of iodine. In the same way, iodine concentration of small Capsicum annuum L. cultivar at pre-ripeness stage was significantly higher than the big one. At such phenological stage it will be advised people to eat small Capsicum annuum L. fruit than the big one when fruit changes. Duration of "sowing-flowering", "sowing-fruit set" and "sowing-fructification" in small Capsicum annuum L. cultivar was shorter than in the big one. Such shorter duration of small Capsicum annuum L. will allow the early obtention of its fruits than those from the big one and thus, their early selling. Â

Evaluation of the volatile fraction, pungency and extractable color of different Italian Capsicum annuum cultivars designed for food industry

The volatile fraction investigated by means of HS-SPME/GC–MS technique, the extractable color in terms of ASTA units, and the pungency measured on the Schoville scale of different experimental Capsicum annuum powders, designed for food industry, were evaluated in this study. In particular, six Capsicum annuum cultivars were included; fresh fruits were cultivated, harvested, dried and grinded to obtain different chilli powder samples that were analyzed and compared with an additional sample purchased from the market. Extractable color ranged between 36.9 ± 1.5 and 144.2 ± 0.8 ASTA units, while pungency was from 999 ± 42 to 47,814 ± 971 SHU units, showing an inverse trend between these two parameters. The volatile fraction of samples resulted to be composed of 64 volatiles belonging to different chemical classes among which terpenes and pyrazines were the most represented ones. The differences and similarities among the chilli pepper varieties were visualized by means of Principal Component Analysis (PCA) as by Heat Map analysis.

1H NMR-based fingerprinting of eleven Mexican Capsicum annuum cultivars.

Approximately 90% of the chili peppers consumed in the world are harvested in Mexico. The present article describes the untargeted 1H NMR-based metabolomic profiling of 11 cultivars of Capsicum annuum species which are routinely consumed worldwide. The metabolomic fingerprinting detected via 1H NMR contained 44 metabolites including sugars, amino acids, organic acids, polyphenolic acids and alcohols which were identified by comparison with the literature data, with Chenomx database and by 2D NMR. Statistical approaches based on principal component analysis (PCA) and linear discriminant analysis (LDA) were used to classify the Capsicum annuum cultivars according to their metabolite profile. LDA revealed metabolomic differences and similarities among Capsicum annuum cultivars, whereas hierarchical cluster analysis (HCA) significantly separated the cultivars according to the phylogenetic trees obtained. Substantial endogenous levels of free amino acids and carbohydrates were detected in all the studied cultivars but interestingly, Capsicum annuum cv. mirasol and C. annuum cv. chilaca contained almost three-fold more endogenous levels of vitamin C than the other cultivars. Considering that this antioxidant was found in crude aqueous extracts, its abundance could be directly proportional to its bioavailability for human nutrition. The results suggest that 1H NMR is an effective method to determine differences among cultivars of the Capsicum annuum species.

A MYB transcription factor is a candidate to control pungency in Capsicum annuum.

Identification of a novel pungency-controlling gene Pun3, which acts as a master regulator of capsaicinoid biosynthetic genes in Capsicum annuum. Capsaicinoid is a unique compound that gives hot peppers (Capsicum spp.) their spicy taste. The Pun1 and Pun2 loci are known to control pungency in Capsicum species. Whereas Pun1 encodes an acyltransferase, the identity of Pun2 is currently unknown. Here, we used recombinant inbred lines and F2 plants derived from a cross between the non-pungent C. annuum accession 'YCM334' and the pungent C. annuum cultivar 'Tean' to identify a novel non-pungency locus. Inheritance studies showed that non-pungency in C. annuum 'YCM334' is controlled by a single recessive gene, which we named Pun3. Using a high-density SNP map derived from genotyping-by-sequencing, Pun3 was mapped to chromosome 7. By comparing physical information about the Pun3 region in the C. annuum 'Zunla-1' and C. chinense 'PI159236' reference genomes, we identified candidate genes in this target region. One cDNA sequence from 'PI159236' was homologous to an unannotated gene in 'Zunla-1.' This sequence was also homologous to CaMYB31, which is expressed only in 'Tean' and harbors one stop codon in the non-pungent accession 'YCM334.' RNA-Seq analysis showed that major structural genes in the capsaicinoid biosynthetic pathway were significantly downregulated in 'YCM334' compared to pungent pepper. Therefore, CaMYB31 is a candidate gene for Pun3, which may act as a master regulator of capsaicinoid biosynthetic genes in pepper.

Identification of Resistance to Powdery Mildew in Chile Pepper

Powdery mildew [Leveillula taurica (Lév.) Arn] is a fungus causing epidemics on chile peppers (Capsicum sp.) worldwide. It was first observed in New Mexico in the late 1990s and has been a reoccurring issue. During the 2017 growing season, environmental conditions were highly favorable for powdery mildew development and severe infection was observed. This provided a unique opportunity to identify novel sources of resistance in Capsicum to powdery mildew. In the present study, the incidence and severity of powdery mildew was evaluated for 152 chile pepper accessions comprising different cultivars and species. Major differences in disease severity and incidence were observed among the accessions. Of the 152 accessions, 53 were resistant, i.e., received a disease index (DI) score of ≤1. When examining across Capsicum species, 16 Capsicum annuum accessions, all 8 Capsicum baccatum, all 21 Capsicum chinense, 5 of 6 Capsicum frutescens, the Capsicum chacoense accession, and the Capsicum rhomboideum accession were resistant. These results provide several accessions with resistance that can be used in breeding programs. Especially important are the C. annuum resistant accessions, as this resistance can be more quickly incorporated into commercially important C. annuum cultivars as compared with interspecific hybridizations.

English

In this study, the capsaicin content of chile pepper extracts from 29 unexplored varieties of Capsicum (twenty five varieties of Capsicum chinense and five of Capsicum annuum) was quantified and correlated with the antimicrobial potential against bacterial and fungal pathogens. The capsaicin content and bactericidal activity against numerous human pathogens (Salmonella, Escherichia coli O157:H7, Listeria monocytogenes, Staphylococcus aureus, Candida albicans) was compared to identify the most effective chile pepper varieties in the treatment of bacterial and fungal pathogens. The capsaicin content of the tested varieties varied from 29 to 42,633 ppm (139 - 682,135 SHU). On average, the fruits of C. chinense cultivars contained much higher concentrations of capsaicin than C. annuum cultivars. The undiluted chile peppers extracts with capsaicin concentrations greater than 25,000 SHU demonstrated bactericidal and antifungal effects. Overall, it was determined that L. monocytogenes and S. aureus were more susceptible to the antimicrobial effects of capsaicin than Salmonella and E. coli O157:H7, while C. albicans was markedly more susceptible than all bacterial species examined. The extract of the sixth most pungent cultivar, C. chinense Bhut Jolokia Red, showed the greatest antimicrobial potency of all screened peppers. The antimicrobial activity of pepper extracts was not directly correlated with increasing capsaicin concentrations, indicating that various Capsicum cultivars may possess distinct capsaicin derivatives. This is the first study which showed the relationship between capsaicin contents in different Capsicum varieties and their antimicrobial potential, and opens avenues in the study of capsaicin derivatives and their role in health and medicines. Key words: Capsicum, pathogen, capsaicin, peppers, antimicrobial, bactericidal.

Identification of Cucumber mosaic resistance 2 (cmr2) That Confers Resistance to a New Cucumber mosaic virus Isolate P1 (CMV-P1) in Pepper (Capsicum spp.).

Cucumber mosaic virus (CMV) is one of the most devastating phytopathogens of Capsicum. The single dominant resistance gene, Cucumber mosaic resistant 1 (Cmr1), that confers resistance to the CMV isolate P0 has been overcome by a new isolate (CMV-P1) after being deployed in pepper (Capsicum annuum) breeding for over 20 years. A recently identified Indian C. annuum cultivar, “Lam32,” displays resistance to CMV-P1. In this study, we show that the resistance in “Lam32” is controlled by a single recessive gene, CMV resistance gene 2 (cmr2). We found that cmr2 conferred resistance to CMV strains including CMV-Korean, CMV-Fny, and CMV-P1, indicating that cmr2 provides a broad-spectrum type of resistance. We utilized two molecular mapping approaches to determine the chromosomal location of cmr2. Bulked segregant analysis (BSA) using amplified fragment-length polymorphism (AFLP) (BSA-AFLP) revealed one marker, cmvAFLP, located 16 cM from cmr2. BSA using the Affymetrix pepper array (BSA-Affy) identified a single-nucleotide polymorphism (SNP) marker (Affy4) located 2.3 cM from cmr2 on chromosome 8. We further screened a pepper germplasm collection of 4,197 accessions for additional CMV-P1 resistance sources and found that some accessions contained equivalent levels of resistance to that of “Lam32.” Inheritance and allelism tests demonstrated that all the resistance sources examined contained cmr2. Our result thus provide genetic and molecular evidence that cmr2 is a single recessive gene that confers to pepper an unprecedented resistance to the dangerous new isolate CMV-P1 that had overcome Cmr1.

Evaluation of a New Mexico Landrace and Two Commercial Chile (Capsicum annuum) Cultivars under Four Furrow Irrigation Schedules

Commercial and landrace chile (Capsicum annuum) cultivars are cultivated under furrow irrigation systems in Northern New Mexico. Yield and physiological differences between commercial and landrace chile cultivars under furrow irrigation systems have not been evaluated. In 2011 and 2012 two commercial chiles, ‘Sandia’ and ‘NuMex Big Jim’, with one landrace chile, ‘Chimayo’, were evaluated under four irrigation schedules, with irrigation once every 7, 9, 11, and 13-days. These four schedules represent possible water availability for farmers in Northern New Mexico. In 2011 there were inconsistent yield patterns; fresh red chile yield of ‘Chimayo’ at the seven-day interval was 90% more than at the nine-day interval. ‘Sandia’ had 138% better yields at the seven- than at the nine-day interval. ‘Chimayo’ fresh green chile yields at the nine-day interval were 47% better than the seven-day interval. ‘NuMex Big Jim’ fresh green yields were 40% greater at the seven-day interval than the 13-day interval. In 2012 no yield components were statistically different for cultivars across irrigation intervals. This data shows commercial green and landrace chile cultivars can be furrow irrigated as water becomes available on 7, 9, 11, or 13-day intervals with no yield effect.

Antioxidant activities and bioactive compounds of five Jalopeno peppers (Capsicum annuum) cultivars

The present study was designed to evaluate the contents of different antioxidants compounds and their antioxidant activities in Jalopeno peppers (Capsicum annuum) cultivars (El Dorido, Grande, Tula, Sayula and El Rey) extracts. Free radical scavenging activity of Grande was recorded as high as 87% followed by El Dorido (83%). Results of reducing power (Fe3+ to Fe2+) showed that Grande (0.85%) and El Dorido (0.81%) fruit extract absorbance value were close to synthetic antioxidant BHT (0. 97%) obtained at100 μg/mL. The results showed that total phenolic content of El Dorido and Grande were significantly higher compared to other Jalapeno pepper. Results indicated strong and positive correlation between antioxidant activity and carotenoids content (r = 0.75), vitamin C (r = 0.78) and total capsaicinoids (r = 0.84), respectively. The results of the antioxidant activity assays showed that the El Dorido and Grande had strongest antioxidant activity compared to other peppers cultivars in this study.

Yield, Capsaicin Content and Peroxidase Enzyme Activity of Four Chili Cultivars on Three Environments

The experiment aimed to determine the effect of different environment (altitude and drought stress) on the growth, yield per plants, capsaisin levels, and peroxidase activities of four chili cultivars. Capsicum annuum (‘Lado’ and ‘Gada’) and Capsicum frutescens (‘Pelita’ and ‘Sona’) were grown with standard cultivation in medium land (± 700 m asl, Kaliurang) and low land (112 m asl, Bulaksumur) in two environments i.e. standard cultivation and drought treatment. The cultivars were arranged in Complete Randomize Design with four replications in each environment. The data were analyzed using analysis of variance with orthogonal contrast model, while the GGE biplot was applied for identification of stability. The result showed significant interaction between environment and cultivar on plant height, fruit’s weight per plant and the contents of capsaicin. Medium land of Kaliurang had suitable environment for chili cultivation of four cultivars and the high capsaicin content of C. frutescens. ‘Gada’ was significantly higher than other cultivars for fruit weight per plant in all planting conditions, while ‘Sona’ had the highest capsaicin content and was stable in all environments. Drought stress increased capsaicin content in low capsaicin content variety, in contrast to high capsaicin content cultivar. Peroxidase enzyme activity of C. frutescens was significantly higher than C. annuum, while C. annuum cultivars also shown significantly different in peroxidase activity.