Charleston Belle Research Articles

Improved Resistance to Root-knot Nematode Species in an Advanced Inbred Line of Specialty Pepper (Capsicum annuum)

Bell and chili peppers are important vegetable and spice commodities worldwide. Significant yield reductions have been attributed to damage caused by root-knot nematodes (RKNs; Meloidogyne spp.). This study addresses the need for developing pepper varieties that have high resistance to RKN, which is now of increasing importance due to restrictions on the use of fumigant nematicides. Our goal is to provide a nonchemical alternative to sustain commercial pepper production in Florida, which is a major producer of peppers in the United States. We evaluated ‘UFRJ107(6)A3’, an advanced inbred line developed from a cross between Capsicum annuum L. ‘Jalapeno’ and ‘Round of Hungary’, for resistance against the nematode in comparison with the parental and three other Capsicum cultivars, namely, C. annuum ‘Charleston Belle’, ‘California Wonder’, and C. chinense Jacq. ‘Datil’ in two separate growth chamber experiments. Based on egg mass indices and reproduction factors, ‘UFRJ107(6)A3’ was significantly more resistant to M. incognita compared with the other five cultivars. When tested with five RKN species, ‘UFRJ107(6)A3’ showed comparably high levels of resistance to M. arenaria and M. floridensis as ‘California Wonder’ based on the nematode reproduction factor. In ‘UFRJ107(6)A3’, however, there were no detectable M. arenaria egg masses, and M. incognita reproduction was minimal compared with that of ‘California Wonder’; both cultivars supported the reproduction of M. enterolobii and M. javanica, although the reproduction factors of M. enterolobii were ≈10-fold higher than M. javanica. To characterize the mechanism of high resistance to M. incognita in ‘UFRJ107(6)A3’, we examined the extent to which infective second-stage juveniles (J2s) were able to penetrate its roots in comparison with the susceptible ‘California Wonder’ and ‘Datil’ in two independent experiments; we conducted RKN root penetration assays with a single plant in a pot and two plants in a single-pot choice test using ‘Datil’ and ‘California Wonder’, respectively, as susceptible standards. In both assays, M. incognita J2s were absent in the roots of ‘UFRJ107(6)A3’ 7 days after inoculation but were present in the susceptible cultivars, indicating that resistance has an effect at the root invasion stage. In growth chamber experiments, at constant temperatures of 28 and 30 °C, ‘UFRJ107(6)A3’ exhibited M. incognita resistance superior to its parents and to the standard resistant bell pepper ‘Charleston Belle’, thus offering the potential to enhance specialty pepper production and for use as a nematode-resistant rootstock for commercial bell peppers.

Resistant Pepper Carrying N, Me1, and Me3 have Different Effects on Penetration and Reproduction of Four Major Meloidogyne species.

Root-knot nematode (Meloidogyne spp.) exhibits a substantial problem in pepper production, causing reduction in yield throughout the world. Continued assessment for root-knot resistance is important for developing new resistance cultivars. In this study, the effect of Me and N genes on the penetration and reproduction of M. incognita race 3, M. arenaria race 1, M. javanica, and M. haplanaria was examined under controlled greenhouse conditions using susceptible and resistant pepper lines/cultivars (Mellow Star, Yolo Wonder B, Charleston Belle, HDA-149, HDA-330, PM-217, and PM-687) differing in the presence or absence of resistant genes. The penetration and resistance responses of these pepper lines differed depending on the nematode species. More second-stage juveniles penetrated roots of susceptible control cultivar Mellow Star than roots of resistant cultivars/lines. Although, there was no significant difference in the nematode penetration among resistant lines 1 and 3 days after inoculation (DAI), variability in the penetration of M. incognita, M. javanica, and M. haplanaria was observed 5 DAI. This demonstrates the variability among different nematode resistance genes to invasion by Meloidogyne spp. Based on nematode gall index (GI) and reproduction factor (RF), Charleston Belle, HDA-149, PM-217 and PM-687 showed very high resistance (GI < 1 and RF < 0.1) to M. incognita, M. arenaria, and M. javanica. Although, all the Meloidogyne-resistant pepper lines evaluated were resistant to M. javanica and M. haplanaria, the susceptible cultivar Mellow Star was a good host for all nematode species having an RF ranging from 8.1 to 34.7. The N, Me1, and Me3 genes controlled resistance to reproduction of all species of Meloidogyne examined.

Comparison between the N and Me3 genes conferring resistance to the root-knot nematode (Meloidogyne incognita) in genetically different pepper lines (Capsicum annuum)

Genetic resistance to Meloidogyne incognita in pepper (Capsicum annuum) has been well characterised for the N and Me3 resistance genes. However, there are no studies comparing the effects of these two genes directly or investigating the combined effects when both genes are present together. Several studies were undertaken to investigate the relationship of the N and Me3 gene systems to one another and to assess whether these two genes are allelic or truly separate genes. Two genotypes homozygous for the N gene (‘Carolina Wonder’ and ‘Charleston Belle’) and two genotypes homozygous for the Me3 gene (HDA 149 and PM 687) were compared in a replicated greenhouse test for reaction to M. incognita race 3. There were no significant differences between the resistant reactions of genotypes possessing the N or Me3 gene. Allelism tests were performed using the F2 populations of the parental genotypes HDA 149 × ‘Charleston Belle’ and HDA 149 × ‘Carolina Wonder’. The results of these studies clearly show the N and Me3 genes to be distinct, separate dominant resistance genes conferring resistance to M. incognita race 3 and not alleles of the same gene.

Stability of Resistance to Root-knot Nematodes in ‘Charleston Belle’ and ‘Carolina Wonder’ Bell Peppers in a Sub-tropical Environment

Two root-knot nematode-resistant bell pepper cultivars, ‘Charleston Belle’ and ‘Carolina Wonder’ (Capsicum annuum L. var. annuum], and their susceptible parents, ‘Keystone Resistant Giant’ and ‘Yolo Wonder B’, were compared for managing the southern root-knot nematode [Meloidogyne incognita (Chitwood) Kofoid and White] in fall and spring tests at Citra, FL. In the fall test, ‘Charleston Belle’ and ‘Carolina Wonder’ exhibited minimal root galling and nematode reproduction, and ‘Keystone Resistant Giant’ and ‘Yolo Wonder B’ exhibited severe root galling and high nematode reproduction. Fruit yield of ‘Charleston Belle’ was 97% greater than yields of the two susceptible cultivars (P ≤ 0.006). In the spring test, one-half of the plots were treated with methyl bromide/chloropicrin before planting the same four bell pepper cultivars. ‘Keystone Resistant Giant’ and ‘Yolo Wonder B’ grown in untreated control plots exhibited severe root galling and high nematode reproduction, but the other six cultivar × methyl bromide combinations exhibited minimal root galling and nematode reproduction. Although soil temperatures (10-cm depth) were greater than 30 °C on 78 days and 57 days during the Fall 2002 and Spring 2003 trials, respectively, resistance did not break in ‘Charleston Belle’ and ‘Carolina Wonder’ in either test. These results demonstrate that root-knot nematode-resistant cultivars such as Charleston Belle and Carolina Wonder are viable alternatives to methyl bromide for managing southern root-knot nematode in bell pepper in sub-tropical environments.

Host Resistance and Metam Sodium for Managing Root-knot Nematodes in a Pepper–Cucumber Rotation

Root-knot nematode-resistant `Charleston Belle' bell pepper (Capsicum annuum L. var. annuum) and metam sodium treatment were evaluated for managing the southern root-knot nematode [Meloidogyne incognita (Chitwood) Kofoid and White] in fall-cropped cucumber (Cucumis sativus L.). `Charleston Belle' and its susceptible recurrent parent, `Keystone Resistant Giant', were planted as spring crops at Blackville, S.C., and Tifton, Ga. `Charleston Belle' exhibited high resistance and `Keystone Resistant Giant' was susceptible at both locations. After termination of the bell pepper crop, one-half of the plots were treated with metam sodium delivered through the drip irrigation system. Cucumber yields and numbers of fruit were highest for cucumber grown in plots treated with metam sodium following either `Charleston Belle' or `Keystone Resistant Giant'; however, root gall severity and numbers of M. incognita eggs in the roots were lowest for cucumber grown in plots treated with metam sodium following `Charleston Belle'. Conversely, root gall severity and nematode reproduction were highest for cucumber grown in plots following `Keystone Resistant Giant' without metam sodium treatment. Application of metam sodium through the drip irrigation system following a spring crop of root-knot nematode-resistant bell pepper should reduce severity of root galling and reproduction of M. incognita as well as increase fruit yield of fall-cropped cucumber.

Minghella's Mountain

FILM REVIEW Minghella's Mountain David Heddendorf IN CHARLES FRAZIER'S 1997 NOVEL COLD MOUNTAIN, the transplanted Charleston belle Ada Monroe ponders the wording of a letter she is writing to Inman, the Confederate soldier she awaits. At last she writes a single sentence, "Come back to me is my request," taking the line from "a ragged love song." The borrowed lyric signals her growth from "pose and irony" to "just saying what your heart felt, straight and simple and unguarded" (272). In the recent film version of Cold Mountain, written and directed by Anthony Minghella, Ada also writes "Come back to me" in a letter, but she is not recalling a song, or thinking about how best to express herself. The line occurs as part of an emphatic voiceover appeal: "If you are fighting, stop fighting. If you are marching, stop marching....Come back to me is my request." We hear the letter read aloud to the wounded Inman, who shortly afterward climbs from his hospital window and begins his long walk home. The revised handling of the letter is typical. Where Frazier the novelist slowly initiates characters into new outlooks on life, Minghella tightens his cinematic focus on a love story. By Frazier's own account in an article for Salon, Cold Mountain owed its original impulse not to the Civil War, and still less to the Ada-Inman romance, but to his fascination with "a very old way of life" in the Appalachian Mountains. Needing a "point of access" into this dimly recalled world, Frazier chose the war and the love story that Minghella recognized as the makings of an epic movie. Under Minghella's direction the readyfor -Hollywood themes become the heart of the picture, while the old way of life fades into the background. At first a reader might notice few differences in the film, aside from the usual screenplay tweaking: scenes shuffled, episodes conflated, lines of dialogue redistributed. The "goatwoman" Inman stumbles across in the woods is made into his rescuer in the film, after he and the preacher Veasey are shot by the Home Guard. Where Inman hunts down three Federal raiders who have terrorized a widowed mother, Minghella streamlines and softens the brutal episode. Such revisions have little effect on the overall story, while helping to squeeze Frazier's sprawling tale into a two-and-a-half-hour movie. 58 Other changes, however, say more about Minghella's artistic design. For instance, Inman carries a copy of William Bartram's Travels through both novel and film. While Frazier has Inman discover the book in a box of charitable donations, Minghella's Ada gives the Travels to Inman as a going-away present, thus staging their passionate farewell. Instead of consoling Inman with beloved landscape descriptions, the battered volume becomes his Ada-talisman and a hiding-place for his sweetheart's portrait. Frazier fans who see the film might miss a scene in which Ada and her friend Ruby encounter a great blue heron that approaches them, staring, before spreading its wings and taking flight. In lieu of this bird passage Minghella invents another. As Inman lies gurgling with his horrible throat wound, a dove fills the screen with translucent wings, heralding a dreamlike flashback in which Ada and Inman stand in an empty church. The dove, we discover, is trapped in the building. Nearly wordless, the couple exchange soulful looks as Inman tenderly captures the dove and releases it at the door. The haunting scene is almost impossible to imagine in Frazier's novel. For one thing, Frazier's Inman would more likely draw his fearsome LeMat's pistol and blast the bird out of the air. This reluctant soldier, as portrayed in the novel, canbe ruthless and cold-blooded. He doesn't just talk about how the war has ravaged his spirit—he routinely shoots and clubs men to death. Killing in self-defense or on behalf of others, he is nonetheless hard and remorseless, and speaks in harsh, sardonic accents. Genteel Ada, plenty prickly herself, meets her match in his proud, detached silences. Minghella sands the edges off these difficult characters, and converts them into warm, attractive people. As in...

Double-Cropping Cucumbers and Squash After Resistant Bell Pepper for Root-Knot Nematode Management.

'Charleston Belle', a root-knot nematode-resistant pepper (Capsicum annuum var. annuum [Grossum Group]), and its susceptible recurrent parent, 'Keystone Resistant Giant', were compared as spring crops for managing the southern root-knot nematode (Meloidogyne incognita) in fall-cropped cucumber (Cucumis sativus) and squash (Cucurbita pepo) at Blackville, SC and Tifton, GA. 'Charleston Belle' exhibited minimal root galling and nematode reproduction, and 'Keystone Resistant Giant' exhibited severe root galling and high nematode reproduction. Cucumber grown in plots following 'Charleston Belle' had lower (P ≤ 0.001) root gall severity indices than following 'Keystone Resistant Giant' (4.2 versus 4.9, respectively). Cucumber yields were 87% heavier (P ≤ 0.0001) and numbers of fruit were 85% higher (P ≤ 0.0001) in plots previously planted to 'Charleston Belle' than to 'Keystone Resistant Giant'. Squash grown in plots following 'Charleston Belle' had lower (P ≤ 0.001) root gall severity indices than following 'Keystone Resistant Giant' (4.0 versus 4.8, respectively). Squash yields were 55% heavier (P ≤ 0.01) and numbers of fruit were 50% higher (P ≤ 0.001) in plots previously planted to 'Charleston Belle' than to 'Keystone Resistant Giant'. These results demonstrate that root-knot nematode-resistant bell pepper cultivars such as 'Charleston Belle' are useful tools for managing M. incognita in double-cropping systems with cucurbit crops.

Response of Bell Pepper Cultivars Near-isogenic for the N Gene to Meloidogyne incognita in Field Trials

Resistance of two sets of bell pepper [(Capsicum annuum L. var. annuum (Grossum Group)] cultivars near-isogenic for the N gene that conditions resistance to root-knot nematodes [Meloidogyne incognita (Chitwood) Kofoid and White, M. arenaria (Neal) Chitwood races 1 and 2, and M. javanica (Treub) Chitwood] was evaluated in field tests at Blackville, S.C. and Charleston, S.C. The isogenic bell pepper sets were `Charleston Belle' (NN) and `Keystone Resistant Giant' (nn), and `Carolina Wonder' (NN) and `Yolo Wonder B' (nn). The resistant cultivars Charleston Belle and Carolina Wonder were highly resistant; root galling was minimal for both cultivars at both test sites. The susceptible cultivars Keystone Resistant Giant and Yolo Wonder B were highly susceptible; root galling was severe at both test sites. `Charleston Belle' had 96.9% fewer eggs per g fresh root than `Keystone Resistant Giant', and `Carolina Wonder' had 98.3% fewer eggs per g fresh root than `Yolo Wonder B' (averaged over both test sites). `Charleston Belle' and `Carolina Wonder' exhibited a high level of resistance in field studies at both sites. These results demonstrate that resistance conferred by the N gene for root-knot nematode resistance is effective in field-planted bell pepper. Root-knot nematode resistant bell peppers should provide economical and environmentally compatible alternatives to methyl bromide and other nematicides for managing M. incognita.

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.

Characterization of Resistance Conferred by the N gene to Meloidogyne arenaria Races 1 and 2, M. hapla, and M. javanica in Two Sets of Isogenic Lines of Capsicum annuum L.

Two isogenic sets of bell pepper (Capsicum annuum L.) lines (differing at the N root-knot nematode resistance locus) were characterized for resistance to Meloidogyne arenaria (Neal) Chitwood races 1 and 2, M. hapla Chitwood, and M. javanica (Treub) Chitwood in greenhouse and growth chamber tests. The isogenic sets of C. annuum were `Charleston Belle' (NN) and `Keystone Resistant Giant' (nn-recurrent parent), and `Carolina Wonder' (NN) and `Yolo Wonder B' (nn-recurrent parent). Meloidogyne arenaria race 1 is pathogenic to C. annuum. `Charleston Belle' and `Carolina Wonder' exhibited high resistance to M. arenaria race 1. Their respective recurrent backcross parents, `Keystone Resistant Giant' and `Yolo Wonder B', were susceptible to M. arenaria. Meloidogyne arenaria race 2 and M. javanica are not highly pathogenic to pepper. However, `Charleston Belle' and `Carolina Wonder' both exhibited higher (P≤0.05) resistance to M. arenaria race 2 and M. javanica than `Keystone Resistant Giant' and `Yolo Wonder B'. Meloidogyne hapla is pathogenic to pepper. Both `Charleston Belle' and `Carolina Wonder' and their respective recurrent parents, `Keystone Resistant Giant' and `Yolo Wonder B', were susceptible to M. hapla. We concluded that the N gene confers resistance to M. arenaria races 1 and 2, and M. javanica in C. annuum, but the N gene does not condition resistance to M. hapla.

Modified Expression of the N Gene for Southern Root-knot Nematode Resistance in Pepper at High Soil Temperatures

Heat stability of the N gene that confers resistance to the southern root-knot nematode, Meloidogyne incognita (Kofoid &amp; White) Chitwood in pepper (Capsicum annuum L.), was determined at 24, 28, and 32°C. Responses of resistant bell pepper cultivars Charleston Belle and Carolina Wonder (homozygous for the N gene) and their respective susceptible recurrent backcross parents, `Keystone Resistant Giant' and `Yolo Wonder B', to M. incognita were compared. Numbers of eggs/g fresh root, reproductive factor of M. incognita, numbers of second-stage juveniles in soil, egg mass production, and root galling increased (P &lt; 0.05) for all cultivars as temperature increased. The response of the resistant cultivars to temperature increase was less dramatic than the response of the susceptible cultivars. Both `Charleston Belle' and `Carolina Wonder' exhibited a partial loss of resistance at 28 and 32 °C. Reproduction of M. incognita was minimal on the resistant cultivars at 24 °C, but increased at higher temperatures. However, at 32 °C reproduction of M. incognita on the resistant cultivars was only 20% of that on the susceptible cultivars and root gall indices were within the range considered moderately resistant. Unlike the susceptible cultivars, the shoot dry weights of the resistant cultivars were not suppressed at 32 °C. This suggests that `Charleston Belle' and `Carolina Wonder' may be somewhat tolerant to M. incognita at high soil temperatures. Although results indicate a partial loss of resistance occurred in `Charleston Belle' and `Carolina Wonder' under high soil temperatures, resistant cultivars may be a useful component of cropping systems designed to manage M. incognita in hot climates.