Bell Pepper Genotypes Research Articles

Differential responses of bell pepper genotypes to indigenous Pseudomonas putida A32 treatment: implications for drought resilience.

This study aimed to evaluate the potential of endophytic plant growth-promoting bacterium (PGPB), Pseudomonas putida A32, to mitigate drought stress in two bell pepper genotypes, Amfora 19 and Amfora 26, and to assess the genotype-specific responses to bacterial treatment. The isolate P. putida A32 was selected for its remarkable beneficial properties, exhibiting 13 out of 14 traits tested. Under drought conditions, Amfora 26 showed increased relative water content and decreased H2O2 and malondialdehyde following bacterial treatment, while Amfora 19 exhibited enhanced growth parameters but responded less to bacterial treatment regarding drought parameters. However, Amfora 19 displayed inherent drought tolerance mechanisms, as indicated by lower stress parameters compared to Amfora 26. The study emphasizes the importance of genotype-specific responses to PGPB treatment and the mechanisms of drought tolerance in peppers. Pseudomonas putida A32 effectively mitigated drought stress in both genotypes, with differential responses influenced by plant genotype. Our study confirmed our initial hypothesis that Amfora 19, as a genotype tolerant to biotic stress, is also more tolerant to abiotic stress. Understanding these interactions is crucial for the development of customized strategies to improve plant productivity and tolerance to drought.

Characterisation of bell pepper (Capsicum annuum L. var. grossum Sendt.) accessions for genetic diversity and population structure based on agro-morphological and microsatellite markers

Bell pepper (Capsicum annuum L. var. grossum Sendt.) is a leading Solanaceous vegetable crop across the world with immense therapeutic and export potential. Such wide cultivation exposes the crop to various biotic and abiotic stresses. Genetic diversity is one of the major prerequisites for any crop breeding programme. Hence, in this study, an attempt was made to evaluate the genetic diversity and population structure of 24 bell pepper genotypes using 25 agro-morphological [9 distinctness, uniformity and stability (DUS) descriptors; 13 quantitative traits; and 3 quality traits] and 82 microsatellite or simple sequence repeat (SSR) markers. Eight DUS descriptors showed polymorphism with maximum morphological variation (H = 1.29) for fruit shape in longitudinal section. Multivariate analysis using Mahalanobis D2 statistic distinguished the genotypes into 11 clusters. With a mean of 4.08 alleles per locus, a total of 151 alleles were generated from 37 polymorphic SSR primers. The polymorphic information content (PIC) ranged from 0.14 (CAMS 451) to 0.76 (CA 525390) with an average of 0.54. The genotypes were divided into two major clusters based on cluster analysis using the unweighted pair group method with arithmetic mean (UPGMA) algorithm, whereas the cluster tree using the neighbour-joining (NJ) method identified three major groups. The population was classified into three groups based on structure analysis. On comparing agro-morphological and molecular clusters, 11 genotypes viz., BWT-39, BWT-39-BR, BWT-39-DR, BWT-29, BWT-3Y, BWT-3Y-4L, Kandaghat Selection, BWT-48-AC, BWT-49-AC, EC-464107, and EC-464115, were found common. These genotypes also exhibited considerable resistance to bacterial wilt disease. Mantel's test showed a moderate positive correlation between agro-morphological (DUS descriptors) and molecular data. Therefore, a combined approach of agro-morphological and molecular evaluation can facilitate the selection of diverse parental lines followed by subsequent hybridisation between them to introduce new traits in bell pepper.

Influence of growth conditions on an antioxidative system in two bell pepper genotypes differing in susceptibility to phytopathogen bacteria Xanthomonas euvesicatoria

Influence of growth conditions on an antioxidative system in two bell pepper genotypes differing in susceptibility to phytopathogen bacteria Xanthomonas euvesicatoria

Variability and association studies for yield and quality characters among bacterial wilt tolerant advanced breeding lines of bell pepper (Capsicum annuum L.)

Forty-three bell pepper genotypes collected from indigenous and exotic sources were evaluated during summer-rainy season, 2018 at Palampur to estimate genetic parameters of variability, heritability, genetic advance and correlation coefficient for yield and quality characters. Results revealed that significant variations were found among genotypes, indicating that yield and quality traits have enough variations. For all the traits studied, recorded values of phenotypic coefficients of variation (PCV) were greater than genotypic coefficients of variation (GCV). GCV was shown to be highest for marketable fruit yield per plant followed by capsanthin content and heritability was observed to be highest for capsanthin content followed by vitamin C. The three characters viz., marketable fruit yield per plant, capsanthin content, and vitamin C have shown high heritability coupled with high genetic advance as a percentage of mean suggesting the predominance of additive genetic control. High heritability coupled with moderate genetic advance was observed in pericarp thickness and TSS indicated the role of slightly additive gene action. Although TSS had a significant negative correlation with Vitamin C, the capsanthin content showed a positive correlation. Vitamin C and capsanthin content had a strong positive correlation with pericarp thickness; however, TSS had a significant negative correlation. There was no significant association between any of the quality parameters and marketable fruit yield per plant indicating that these traits can be improved independently.

Variability and association studies for yield and quality characters among bacterial wilt tolerant advanced breeding lines of bell pepper (Capsicum annuum L.)

Forty-three bell pepper genotypes collected from indigenous and exotic sources were evaluated during summer-rainy season, 2018 at Palampur to estimate genetic parameters of variability, heritability, genetic advance and correlation coefficient for yield and quality characters. Results revealed that significant variations were found among genotypes, indicating that yield and quality traits have enough variations. For all the traits studied, recorded values of phenotypic coefficients of variation (PCV) were greater than genotypic coefficients of variation (GCV). GCV was shown to be highest for marketable fruit yield per plant followed by capsanthin content and heritability was observed to be highest for capsanthin content followed by vitamin C. The three characters viz., marketable fruit yield per plant, capsanthin content, and vitamin C have shown high heritability coupled with high genetic advance as a percentage of mean suggesting the predominance of additive genetic control. High heritability coupled with moderate genetic advance was observed in pericarp thickness and TSS indicated the role of slightly additive gene action. Although TSS had a significant negative correlation with Vitamin C, the capsanthin content showed a positive correlation. Vitamin C and capsanthin content had a strong positive correlation with pericarp thickness; however, TSS had a significant negative correlation. There was no significant association between any of the quality parameters and marketable fruit yield per plant indicating that these traits can be improved independently.

Serada Sonbahar Dönemi Dolmalık Biber Yetiştiriciliğinde Hibrit Çeşit Adaylarının Meyve Kalitesi ve Verim Performansları

Sebzelerde düşük sıcaklık zararı; büyüme ve gelişmeyi olumsuz etkileyerek verim ve kalite kayıplarına neden olan önemli bir abiyotik stres faktörüdür. Örtüaltı sebze yetiştiriciliğinde düşük sıcaklıklar nedeniyle tür ve çeşitlere göre değişmekle birlikte verim ve kalite performansları yönünden önemli düzeyde azalışlar meydana gelmektedir. Bu çalışmada, üniversite sanayi iş birliğiyle yürütülen biber çeşit ıslahı programı kapsamında geliştirilen 28 hibrit dolmalık biber çeşit adayının ısıtmasız serada sonbahar dönemi yetiştiriciliğinde meyve kalite ve verim özellikleri yönünden performanslarının karşılaştırılması amaçlanmıştır. Isıtmasız serada ilk hasatlar, fide dikiminden itibaren 46-58 gün sonra yapılmıştır. Dolmalık biber genotipleri arasında meyve boyu değerleri yönünden istatistiksel olarak önemli düzeyde farklılıkların olduğu bulunmuştur. Meyve eni değerleri, 47.31-55.86 mm arasında değişim göstermiştir. Renk tonları yönünden dolmalık biber genotipleri arasında belirgin farklılıkların olduğu saptanmıştır. Hibrit biber çeşit adaylarında bitki başına meyve sayılarının ortalama 15.6-30.0 adet arasında değiştiği belirlenmiştir. Çalışmada, Samsun ekolojik koşullarında serada hibrit biber çeşit adaylarının dekara verim değerlerinin, 2560.5 kg (HD-16) ile 5102.5 kg (HD-8) arasında değişim gösterdiği saptanmıştır. Araştırma sonucunda incelenen tüm parametreler birlikte değerlendirildiğinde; HD-4, HD-8 ve HD-24 genotiplerinin düşük sıcaklığa tolerant olduğu ve sonbahar dönemi yetiştiriciliği için ümit var hibrit dolmalık biber çeşit adayları olduğu belirlenmiştir.

Effect of Drought Stress on Capsaicin and Antioxidant Contents in Pepper Genotypes at Reproductive Stage.

Pepper is one of the most important vegetables and spices in the world. Principal pungency is contributed by secondary metabolites called capsaicinoids, mainly synthesized in the placenta of pepper fruit. Various factors, including drought, limit pepper production. Flowering is one of the most sensitive stages affected by drought stress. The current study was conducted to determine the effect of drought on different pepper genotypes at the flowering and pod formation stages. Hot pepper (Pusajuala and Ghotki) and Bell pepper (Green Wonder and PPE-311) genotypes were subjected to drought (35% field capacity) at two different stages (flowering (DF) and pod formation (DP) stage). In comparison, control plants were maintained at 65% field capacity. The data regarding flowering survival rates, antioxidant protein activity, and proline content, were collected. Results indicated that parameters like flower survival percentage, number of fruits per plant, and fruit weight had significant differences among the genotypes in both treatments. A high proline level was observed in Green Wonder at the pod formation stage compared to other genotypes. Capsaicin contents of hot pepper genotypes were affected at the pod formation stage. Antioxidants like GPX were highly active (190 units) in Ghotki at pod formation. Bell pepper genotypes had a high APX activity, highly observed (100 units) in PPE-311 at pod formation, and significantly differ from hot pepper genotypes. In the catalase case, all the genotypes had the highest values in DP compared to control and DF, but Pusajuala (91 units) and Green Wonder (83 units) performed best compared to other genotypes. Overall, the results indicate that drought stress decreased reproductive growth parameters and pungency of pepper fruit as most of the plant energy was consumed in defense molecules (antioxidants). Therefore, water availability at the flowering and pod formation stage is critical to ensure good yield and pepper quality.

Estimation of genetic variability, GCA and SCA effects for development of early and high yielding bell pepper hybrids suitable for protected cultivation

The present investigation involves 29 diverse bell pepper genotypes for variability studies and 14 promising lines (11 lines and 3 testers), 33 F1 and 1 standard check for combining ability studies. The objective of the study was to assess the nature and magnitude of genetic variability among the bell pepper genotypes for yield and other horticultural traits and to identify the potential parental lines and cross combinations suitable for the protected environment based on the estimation of general combining ability and specific combining ability. A wide range of variability was observed for most of the characters studied. The genotypes viz., Kashmir Sel-1 (L2), DARL-10 (L9) and UHFSP(Y)-11 (L11) for marketable fruit yield per plant and Kashmir Sel-1 (L2), UHFSP(Y)-11 (L11) and DARL-01 (L5) for earliness were good general combiners and these may be included for exploiting hybrid vigour or development of purelines. On the basis of specific combining ability effects and per se performance, the crosses viz., ARCH-19 (L1) × Solan Bharpur (T1), DARL-10 (L9) × California Wonder (T2) and UHFSP(Y)-11 (L11) × Yolo Wonder (T3) were the best cross combinations for marketable fruit yield per plant and number of marketable fruits per plant under protected environment. The cross combinations viz., DARL-10 (L9) × California Wonder (T2), DARL-01 (L5) × California Wonder (T2), LC (L10) × Solan Bharpur (T1) and Kandaghat Sel-9 (L7) × Solan Bharpur (T1) shows significant negative SCA for earliness and could be used for development of early hybrids.

Susceptibility assessment of bell pepper genotypes to crown and root rot disease

Bell Pepper (Capsicum annuum) is one of the important vegetable crops with valuable food sources, which is used almost around the world. Crown and root rot disease caused by Phytophthora capsici is one of the most important diseases of bell pepper in Iran. The present study was conducted to evaluate the susceptibility of different varieties of bell pepper to crown and root rot disease under glasshouse condition. Fourteen commonly planted genotypes of bell pepper in Iran were evaluated for their susceptibility to infection with the pathogen. For this purpose, disease severity of the chosen genotypes in different growth stages was evaluated. The results indicated that the bell pepper genotypes respond differently to pathogenicity tests. Based on cluster analyses confirmed by the results of SAS analyses, bell pepper cultivars were categorised in five distinct groups.

Morphological Studies of Bell Pepper Germplasm

Morphological characterization of bell pepper (Capsicum annuum L. var. grosssum Sendt.) germplasm is a prerequisite in a crop improvement program. The study was conducted during 2007 and 2008 at the vegetable experimental farm of the CSK Himachal Pradesh Agricultural University, Palampur, Himachal Pradesh, India, to study morphological traits of bell pepper genotypes which include the parents ‘Kandaghat Selection’, ‘EC-464115’, ‘EC-464107’, ‘HC-201’, ‘AC-48’, ‘SKAU-SP-613-1’, ‘PBC-631’, ‘SKAU-SP-633-1’, ‘California Wonder’, ‘Yolo Wonder’, and ‘Solan Bharpoor’ and 24 F1 hybrids from previous Line × Tester mating with comparison to the standard check ‘Bharat’. Characterization of genotypes was done for the plant descriptors fruit shape, fruit shape at pedicel attachment, blossom end fruit shape, fruit position, plant height, and fruit color. Blocky fruit shape, lobate pedicel attachment, sunken blossom end fruit shape, pendent fruit position, and dark green fruit color at the time of horticultural maturity could be desirable horticultural attributes. Bell pepper germplasm contain sufficient genetic variability and can be used for crop improvement. Characterization of bell pepper germplasm will provide valuable information for strengthening breeding programs because it helps in selection of parents on the basis of morphological characters. The character expression of F1s surpassing parents either positively or negatively was comparable to a transgression effect. Resemblance to either parent and intermediate character expression was attributed to dominant and additive gene action, respectively.

Variation in phenolic compounds, ascorbic acid and antioxidant activity of five coloured bell pepper ( Capsicum annum) fruits at two different harvest times

The interest in the consumption of pepper fruits ( Capsicum annuum L.) is, to a large extent, due to its content of bioactive compounds and their importance as dietary antioxidants. In the present study, the effect of harvest time, based on maturity stage, on changes in the phenolic compounds especially, flavonoids such as quercetin and catechin, total phenols, ascorbic acid, antioxidant activity and taste-related compounds such as total soluble solid (TSS) and titritable acidity (TA) in five different coloured bell pepper genotypes, Arian (orange), Marona (purple), Zorro (dark violet), Y-43-09 (red) and Y-43-07 (yellow), grown as hydroponics system was investigated. The results showed that concentration of antioxidant components and taste-related properties varied among the pepper cultivars at both the mature and whole coloured ripened stages. With advanced maturation, total antioxidant activity increased, however some antioxidant components such as ascorbic acid, total phenols decreased. Furthermore, TSS and TA increased with advanced fruits maturation. The concentration of flavonoids such as quercetin and catechin varied greatly among the pepper cultivars at the two maturity stages. Some cultivars exhibited increase in the amount of these compounds and others decrease with maturation. The richest cultivar in quercetin and catechin content was Zorro with dark violet fruits.

RAPD analysis of local bell pepper genotypes in relation with powdery mildew incidence and fruit yield: Managing disease by single chemical molecule

A field study was conducted to investigate powdery mildew disease incidence and fruit yield of locally available bell pepper genotypes by Kharif 2004 and Rabi 2005. The study includes a single chemical molecule in managing the powdery mildew disease during both the seasons. Field studies include five chemical treatments (T1 to T5) plus one water spray control and an untreated control in five replications each. The result shows that out all treatments T5 was best in controlling the powdery mildew disease in genotype Indra by 77.1 and 73.7% of disease decrease over control and 85.3 and 95.7% increase in yield over control respectively during Kharif and Rabi. The next best performing genotypes were Arka Basant and California Wonder in terms of less disease incidence and high yield. Further, the study was extended to relate the selected varieties for its genetic diversity using Random Amplified Polymorphic DNAs, with respect to the disease incidence and yield. The highest genetic dissimilarity of 49% was noticed between the genotypes Indra and Arka Gaurav having contrasting characters such as high and low fruit yield, respectively. The lowest genetic diversity of 21% was noticed between the genotypes Arka Mohini and California Wonder that were similar in most of the morphological characters, fruit yield and susceptibility to the powdery mildew disease. Based on the molecular data, a remarkable difference was exhibited by the commercially grown bell pepper genotypes.

Genetic Variation and Association Analysis for Fruit Yield, Agronomic and Quality Characters in Bell Pepper

Knowledge of the magnitude of genetic variability for marketable fruit yield and quality traits, and relationships among these traits, is needed to improve quality breeding in bell pepper (Capsicum annuum L. var. grossum Sendt.). The study was undertaken to assess genetic variation for marketable fruit yield, fruits per plant, average fruit weight, pericarp thickness, number of lobes per fruit, TSS, and ascorbic acid and capsaicin contents and to quantify the relationship among these traits in diverse bell pepper germplasm. Significant difference among bell pepper genotypes indicated presence of significant variation for all the traits. The phenotypic coefficient of variation (PCV) indicated higher values than genotypic coefficient of variation (GCV) for all traits, indicating close association between phenotype and genotype. High heritability estimates along with high genetic advance was recorded for fruits per plant, marketable fruits per plant, pericarp thickness, and lobes per fruit, indicating the role of additive gene action for their inheritance. Days to 50% flowering, harvest duration, and ascorbic acid had high heritability estimates along with low genetic advance, indicating nonadditive gene activity, and these could be improved through hybridization. In general, genotypic correlations were higher than the corresponding phenotypic correlations, revealing inherent associations among traits. The maximum direct effect on fruit yield per plant was exhibited by fruit per plant followed by harvest duration, average fruit weight, and pericarp thickness, whereas marketable fruits per plant and days to 50% flowering had negative direct effects. This suggests that a selection procedure based on higher fruits per plant, harvest duration, and average fruit weight may be effective in improving fruit yield. Adequate genetic variability was present within available bell pepper germplasm to allow breeding improvement of marketable yield and quality traits.

Ordinal models and generalized estimating equations to evaluate disease severity

Many assays have been carried out in Capsicum spp. in order to evaluate its resistance to Phytophthora capsici , which causes blight and considerable yield loss. An assay aiming at the selection of resistant pepper and bell pepper genotypes to P. capsici was jointly performed in the laboratory of the Phytopathological Clinic of Entomology, Phytopathology and Agricultural Zoology and in the experimental area of the Plant Production Department, both located at ESALQ, University of São Paulo, Brazil. The data set for this assay comes from ordinal categorized random variables, whose analysis does not generally take into account the ordinal nature of the responses, but instead, builds indexes, among other measures, in order to evaluate the resistance of the studied genotypes. This work presents ordinal generalized linear fits in order to evaluate blight severity as well as to identify and select new resources to the pathogen. It also analyses the estimating equations proposed by Liang & Zeger (1986a, b) in order to obtain an infection pattern for the disease. From the fit of the cumulative logit models, valuable genotypes are identified for genetic breeding programs.

Heat Stability of Resistance to Southern Root-knot Nematode in Bell Pepper Genotypes Homozygous and Heterozygous for the N Gene

Expression of the N gene, which confers resistance to southern root-knot nematode (Meloidogyne incognita Kofoid and White) in bell pepper [(Capsicum annuum L. var. annuum (Grossum Group)], is modified at high temperatures (28 °C and 32 °C), but its expression in the heterozygous condition (Nn) has not been documented at moderate or high temperatures. Responses of the near-isogenic bell pepper cultivars, Charleston Belle and Keystone Resistant Giant (differing at the N locus), and the F1 and reciprocal F1 crosses between these cultivars to M. incognita race 3 were determined at 24, 28, and 32 °C in growth chamber experiments. `Keystone Resistant Giant' (nn) was susceptible at 24, 28, and 32 °C. `Charleston Belle' (NN) exhibited high resistance at 24 °C and resistance was partially lost at 28 and 32 °C. However, at 32 °C root gall and egg mass severity indices for `Charleston Belle' were still in the resistant range, and the number of M. incognita eggs per gram fresh root and reproductive index were 97% and 90% less, respectively, than for `Keystone Resistant Giant'. Responses of the F1 and F1 reciprocal hybrid populations to M. incognita were similar to the response of the resistant parent at all temperatures. Root fresh weights and top dry weights indicated that both hybrid populations tolerated M. incognita infections at least as well as `Charleston Belle'. These findings indicate that i) only one of the parental inbred lines needs to be converted to the NN genotype to produce F1 hybrid cultivars with fully functional N-type resistance to M. incognita; and ii) cytoplasmic factors are not involved in expression of N-type resistance and the resistant parental inbred can used to equal advantage as either the paternal or the maternal parent.

Adventitious Shoot Formation and Plant Regeneration from Bell Pepper (Capsicum annuum L.) Cultivars and Dihaploid Lines

Adventitious shoots and viable plants were regenerated from bell pepper (Capsicum annuum L.) cultivars and dihaploid lines (DHLs) obtained from F1 hybrids via androgenesis (Dolcet-Sanjuan et al., in press). Hypocotil and cotyledon sections from in vitro-germinated seeds were used as explants. A modified MS medium (Murashige and Skoog, 1962) supplemented with IAA (0 to 3.2 μM) and BAP (0 to 100 μM) was used in a 3-week-long shoot primordia induction phase. Shoot elongation was best performed in the same basal medium, but supplemented with silver thiosulfate and GA3. Shoots were regenerated from eight selected DHLs (`C213', `C215', `C218', `C2123', `C2125', `C3111', `C3113', and `P493') and two cultivars (`Padrón' and `Yolo Wonder'). The percentage of cotyledon sections with shoot primordia after the induction phase was not genotype-dependent and always higher than with hypocotil sections (93.4% and 17.9%, respectively). The number of shoot primordia per responsive cotyledon section was also higher than with hypocotil sections (3.3 and 1.7, respectively). The genotype had a significant effect on the number of shoots regenerated per responsive cotyledon (1.1 to 5.5) or hypocotil (0.5 to 3.5) section. All adventitiously regenerated plants were fertile. This adventitious shoot regeneration protocol is being used to obtain transgenic plants from sweet bell pepper genotypes.

Screening for in vitro shoot-forming capacity of seedling explants in bell pepper (Capsicum annuum L.) genotypes and efficient plant regeneration using thidiazuron

In vitro shoot regeneration ability of 17 (7 Italian and 10 Hungarian) bell pepper genotypes was investigated using excised cotyledons and rooted hypocotyls as explants. Most of the Italian genotypes and two of the Hungarian genotypes responded well, producing shoots from rooted hypocotyls. Only two genotypes (one Italian and one Hungarian) gave a weak response using cotyledons. For direct shoot induction in these explants, in addition to the methods cited in the relevant papers, a new method was applied using thidiazuron as a cytokinin. Shoots were successfully regenerated from cotyledons of two Italian and two Hungarian genotypes using thidiazuron which were considered to be non responsive to the usual methods.

Effects of Bactericide Treatments on Bacterial Spot Severity and Yield of Different Pepper Genotypes and on Populations of Certain Insects

In a 3-yr study, bell pepper genotypes with different levels of susceptibility to Xanthomonas campestris pv. vesicatoria were treated with bactericides to study disease and yield responses. At Blairsville, Georgia, under moderate disease pressure, a cupric (Cu) hydroxide + mancozeb combination applied at weekly intervals provided moderate disease control and increased yields 76, 117, and 83% during 1987, 1988, and 1989, respectively, on the highly susceptible cultivar Yolo Wonder B (.)