The inheritance of multiple flowers and leaf pubescence resulting from the crosses between accessions from pepper species Capsicum annuum L. and C. chinense Jacq. was examined. Hand cross- and self-pollinations were made in a glass greenhouse. Only eight normal F1 plants were obtained from crosses between the two species when C. annuum L. was the female parent. F2 and backcross generations obtained from the F, and the two parents were grown in the field. Two field studies indicated that multiple flowers and leaf pubescence were controlled by dominant genes. A three-gene model leading to an F2 segregation ratio of 45:9:10 and a two-gene model leading to an F2 segregation ratio of 13:3 were suggested for the inheritance of multiple flowers and leaf pubescence, respectively. Epistasis was evoked in the interpretation of the data. No linkage was found between the two characters. The inconsistencies between F2 and backcross data might be due to selective elimination of genes from one or the other parent in an Interspecific hybridization. Segregation ratios from intraspecific crosses for leaf pubescence supported a two-gene model and gave an F2 ratio of 13 pubescent leaf : 3 glabrous leaf progeny.
D.M. Shuh and James F. Fontenot
Lisa M. Oelke, Paul W. Bosland and Robert Steiner
Despite extensive breeding efforts, no pepper (Capsicum annuum L. var. annuum) cultivars with universal resistance to phytophthora root rot and foliar blight (Phytophthora capsici Leon) have been commercially released. A reason for this limitation may be that physiological races exist within P. capsici, the causal agent of phytophthora root rot and phytophthora foliar blight. Physiological races are classified by the pathogen's reactions to a set of cultivars (host differential). In this study, 18 varieties of peppers were inoculated with 10 isolates of P. capsici for phytophthora root rot, and four isolates of P. capsici for phytophthora foliar blight. The isolates originated from pepper plants growing in New Mexico, New Jersey, Italy, Korea, and Turkey. For phytophthora root rot, nine of the 10 isolates were identified as different physiological races. The four isolates used in the phytophthora foliar blight study were all determined to be different races. The identification of physiological races within P. capsici has significant implication in breeding for phytophthora root rot and phytophthora foliar blight resistance.
David W. Wolff, Wanda W. Collins and Thomas J. Monaco
Several inheritance experiments with bentazon herbicide-tolerant Capsicum annuum `Bohemian Chili' (BCH P1) and susceptible `Keystone Resistant Giant' (KRG, P2) and `Sweet Banana' (SB, P2) were conducted. Populations of plants at the three- to five-leaf stage were treated with a bentazon rate of 4.5 kg·ha-1. Tolerance expression was affected by environment and varied across experiments. F2 and BCP2 generations from both susceptible parent crosses fit the expected ratios for a single, dominant gene conferring tolerance. Reciprocal F1s showed a maternal effect on tolerance intensity not consistently observed in reciprocal BCP2s or at all in reciprocal F2s. Segregation ratios of reciprocal crosses, however, were not heterogeneous, based on x2 tests of observed ratios in seven of eight cases. Variable tolerance expression in expected homogeneous populations (P1, P2, and F1) and lower tolerance in BC3 families suggested that modifying factors affected tolerance. Analysis of genetic components of shoot height and fresh weight generation means showed significant digenic epistasis, primarily additive × dominance. Modifying genes that affect the major gene controlling tolerance in BCH are, therefore, present. The simple inheritance of bentazon tolerance, even though modifying factors were present, facilitated transfer of bentazon tolerance into KRG via backcrossing. Chemical name used: 3-(1-methylethyl)-(1H)-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide (bentazon).
Darren E. Robinson, Kristen McNaughton and Nader Soltani
Pepper growers currently have limited access to many effective broadleaf herbicides. Field trials were conducted over a 3-year period in Ontario to study the effect of tank mixtures of sulfentrazone (100 or 200 g·ha−1 a.i.) with either s-metolachlor (1200 or 2400 g·ha−1 a.i.) or dimethenamid-p (750 or 1500 g·ha−1 a.i.) on transplanted bell pepper. Under weed-free conditions, there was no visual injury or reduction in plant height, fruit number, fruit size, or marketable yield of transplanted pepper with pretransplant applications of sulfentrazone applied in tank mixtures with s-metolachlor or dimethenamid-p. The tank mixture of sulfentrazone + s-metolachlor gave greater than 85% control of redroot pigweed (Amaranthus retroflexus) and eastern black nightshade (Solanum ptycanthum), but only 70% to 76% control of velvetleaf (Abutilon theophrasti), common ragweed (Ambrosia artemisiifolia), and common lambsquarters (Chenopodium album). The combination of sulfentrazone + dimethenamid-p provided good to excellent control of all weed species except velvetleaf. Based on this study, sulfentrazone and dimethenamid-p have potential for minor use registration in pepper.
Robert L. Jarret, Jason Bolton and L. Brian Perkins
Germplasm release 509-45-1 is a small-fruited Capsicum annuum L. pepper released in 2013 by the Agricultural Research Service (ARS) of the U.S. Department of Agriculture (USDA). Fruit of 509-45-1 contain high concentrations of capsiate [(4-hydroxy
John R. Stommel, Mikhail Kozlov and Robert J. Griesbach
Ornamental peppers ( Capsicum annuum L.) belong to the plant family Solanaceae, which includes ornamentals such as the Brugmansia (Angel’s trumpet), Brunfelsia , Browallia (Bush violet), Datura , Nicotiana , Petunia , and Salpiglossis
Hak-Tae Lim, Kei-youn Lee, Yeoung-Sook Yoo and Duck-Chun Yang
Since in vitro regeneration and transformation systems in hot pepper (Capsicum annuum L.) have not been available, the application of new genetic manipulations has been limited. Here we report an efficient procedure to regenerate whole pepper plants and to generate transgenic plants expressing a foreign gene was established. High frequency of plant regeneration was observed when hypocotyl and cotyledon explants were cultured on MS/B5 medium supplemented with NAA 0.05 mg·L–1 plus zeatin 2.0 mg·L–1, NAA 0.05 mg·L–1 plus zeatin 2.0 mg·L–1, IBA 10.0 mg·L–1 plus BA 1.0 mg·L–1, IAA 0.02 mg·L–1 plus zeatin 3.0 mg·L–1. An addition of AgNO3 5–10 μm to these media improved the regeneration rate by about 10%. For plant transformation, hypocotyl and cotyledon explants of pepper were preconditioned on kanamycin-free shoot induction medium for 48 hours. Then, co-cultivation with Agrobacterium tumeaacience was done on the co-culture medium for 2 days. The explants were then blotted in sterile filter paper and placed on shoot induction and selection medium containing kanamycin sulfate (100 mg·L–1) and carbenicillin (500 mg·L–1). PCR showed that the introduced ADA gene was integrated and stably expressed in the regenerated plants. ADA enzyme activities were checked by spectrophotometric analysis.
D. Janik, E. Fava, C.A. Madramootoo and K.A. Stewart
The yield of bell peppers (Capsicum annuum L. cv. King Arthur) was measured when grown in the field under eight mulching/irrigation/nitrogen fertilization systems, was studied at the Macdonald Campus of McGill Univ., using a randomized block design replicated three times. All treatments received a preplant fertilizer application of 60 kg N/ha with four of the treatments receiving additional fertigation during the season. Of the four treatments receiving fertigation, one silver reflective mulched plot and one black mulched plot received an additional 40 kg N/ha in 4 kg N/ha/week over a 10-week period beginning 12 June weekly up to and including 14 Aug. 1995. The remaining two fertigated treatments only received additional N, when leaf nitrogen, based upon leaf chlorophyll content, dropped below a 95% sufficiency index as measured by a Minolta SPAD 502 meter. Marketable yields of the fertigated plots range between 100%–126% higher than those of the control plot for the entire growing season. However, most notably was the early yields (first three harvests), which ranged from 146%–493% higher than that of the control plot, economically, significantly increasing the producers income. The experiment will be duplicated in Summer 1996 to confirm our findings.
Monica Ozores-Hampton, Phillip A. Stansly and Thomas A. Obreza
Methyl bromide will be unavailable to conventional vegetable growers in the year 2005, and it cannot be used by organic growers. Chemical alternatives are more expensive and may also be subject to future restrictions. Non-chemical alternatives like solarization and organic amendments are as yet largely unproven but do offer promise of sustainable solutions free of government regulation. The objective of this study was to evaluate the effects of soil-incorporated biosolids and soil solarization on plant growth, yield, and soil fertility. Main plots were a biosolids soil amendment (37 Mg·ha-1 and a non-amended control. Treated main plots had received some type of organic amendment for the previous 6 years. Sub-plots were fumigated with methyl bromide as they had been for 6 years, or non-fumigated. Non-fumigated plots were further split into solarized and non-solarized plots. Bell pepper (Capsicum annuum `X 3R Aladdin') was grown for 8 months. Nitrogen fertilization was reduced to 50% of the recommended rate in the biosolids plots due to expected N mineralization from the biosolids amendment. Plant biomass was higher in the biosolids plots compared with the non-amended plots but there were no differences in marketable pepper yields between biosolids and non-biosolids plots. Plants grown in solarized soil produced lower plant biomass and yields than the methyl bromide and non-fumigated treatments. Soil pH and Mehlich 1-extractable P, K, Ca, Mg, Zn, Mn, Fe, and Cu were higher in biosolids plots than in non-amended control plots. Soil organic matter concentration was 3-fold higher where biosolids were applied compared with non-amended soil. The results suggest that regular organic amendment applications to a sandy Florida soil can increase plant growth and produce similar yields with less inorganic nutrients than are applied in a standard fertilization program. However, methyl bromide and non-fumigated treatments produced higher yields than soil solarization.
E. Fava, D. Janik, C. Madramootoo and K.A. Stewart
Production of red bell peppers (Capsicum annuum L. cv. King Arthur) is relatively new to Quebec, and management techniques need to be further developed in terms of insect and disease control as well as fertigation techniques. The purpose of the experiment was to compare the fertigation of peppers using either the conventional method (weekly fertigation) or fertigation based on the readings of the SPAD 502 chlorophyll meter. The experiment compared the effects of these fertigation treatments, with respect to insects and diseases, on either a silver or black mulch. The study done in 1995, demonstrated that using the chlorophyll meter saved 28 kg N/ha compared to the weekly fertigated plants. However, this decrease did not affect the population of insects or the disease incidence on the plants. The main differences occurred between the black and silver mulch treatments for aphid populations. Plants on silver mulch had significantly lower numbers of aphids than the other treatments. Plants on black mulch also had low aphid population compared to plants grown on bare soil. The relationship between silver mulch and viruses or tarnished plant bug were not as apparent. However, the viral infections and tarnished plant bug populations on the plants tended to be lower than those on most of the black mulch treatments. Sunscald was not influenced by mulch or fertigation treatments. This may be partly attributed to the amount of leaf area. The number of fruit invaded by European corn borer was too low to draw any conclusions. Blossom end rot, sclerotinia, and bacterial spot were not present in the field in the 1995 season. The results from the 1996 season should further elucidate these results.