Experiments were conducted to estimate the relative importance of additive and dominance genetic variances and non-allelic interactions in the inheritance of resistance to Colletotrichum spp. in strawberry (Fragaria × ananassa Duch.). Progeny of 40 parents crossed in a Comstock and Robinson Design II Mating scheme were inoculated with three isolates of C. fragariae and one isolate of C. acutatum. Disease development on each plant was rated visually. Variance components were estimated and converted to genetic variances. Estimates of were six to 10 times higher than those for Within-family variance not accounted for by equaled 35% and 38% of the total genetic variance in females and males, respectively, indicating probable epistatic effects. The frequency distribution of disease severity ratings was bimodal in both experiments, suggesting major gene action. Narrow-sense heritability estimates were 0.37 and 0.26, and broad-sense heritability estimates were 0.87 and 0.85 for females and males, respectively. Narrow-sense heritability estimates are probably sufficient to produce gains from recurrent selection. Gains from selection of clonal value should be possible because of the high broad sense heritability estimates. It appears feasible to establish a broad genetic-based population resistant to Colletotrichum spp. from which selections could be evaluated per se and/or recombined to produce improved populations.
Creighton L. Gupton and Barbara J. Smith
Shahrokh Khanizadeh, Martine Deschênes, Audrey Levasseur, Odile Carisse, Marie Thérèse Charles, Djamila Rekika, Louis Gauthier, André Gosselin, Rong Tsao, Raymond Yang, Jennifer DeEll, and J. Alan Sullivan
‘St-Jean d'Orléans’ is a new June-bearing strawberry cultivar ( Fragaria × ananassa Duch.) released by Agriculture and Agri-Food Canada, Horticultural Research and Development Center, Quebec. ‘St-Jean d'Orléans’ was introduced because it has
F. Takeda, W.J. Janisiewicz, J. Roitman, N. Mahoney, and F.B. Abeles
Postharvest treatment with pyrrolnitrin (250 mg·liter-1) and low storage temperatures delay postharvest rot development in fall-harvested `Tribute' strawberries (Fragaria × ananassa Duch.). Untreated fruit stored at 18C developed gray mold fruit rot (Botrytis cinerea) and rhizopus rot (leak) by the second day. Fruit that did not develop gray mold or leak eventually developed blue mold rot (Penicillium spp.). No rot was observed at 1C, but gray mold and rhizopus rots developed after berries were transferred to 18C. Pyrrolnitrin delayed the appearance of the various rots by 2 to 4 days, but did not reduce the rate of rot development. Chemical name used: 3-chloro-4-(2'-nitro-3'-chlorophenyl)pyrrole (pyrrolnitrin).
Charles D. Safley, E. Barclay Poling, Michael K. Wohlgenant, Olga Sydorovych, and Ross F. Williams
The costs associated with growing, harvesting and marketing strawberries (Fragaria × ananassa) using the plasticulture production system were estimated to be $13,540/acre ($33,457/ha). Net revenue analysis showed that growers would have to charge at least $0.85 and $1.40/lb ($1.87 to $3.09/kg) for pick-your-own (PYO) and prepicked fruit, respectively, and sell 12,000 lb of berries per acre (13,449.9 kg·ha-1) to cover this expense. Break-even analysis indicated that growers would have to charge a PYO price of $0.65/lb ($1.43/kg) and $1.20/lb ($2.64/kg) for prepick berries and sell a minimum of 15,041 lb/acre (16,858.4 kg·ha-1) to cover the projected expenses. However, if a grower received $0.95 and $1.50/lb ($2.09 and $3.31/kg) for the PYO and prepicked fruit, respectively, he/she would only have to sell 10,622 lb of berries per acre (11,905.4 kg·ha-1) to break even. It was assumed that an average of 11.6 lb (5.26 kg) of fruit would be sold to PYO customers and an average of 7.1 lb (3.22 kg) would be sold to customers who visited the fruit stand. Under these assumptions, the breakeven yield of 14,724 lb/acre translates into a requirement to sell fruit to at least 1,539 customers per acre (3,802.8 customers/ha) at the lowest combination of prices while a yield of 10,398 lb/acre converts to a minimum of 1,087 customers per acre (2,685.9 customers/ha) at the higher prices. Customers were also surveyed at direct market operations in Spring 1999 to gain insight into consumer demographic characteristics, why customers select a specific PYO or prepick direct market strawberry outlet, average expenditures per customer, typical driving distances to direct market strawberry operations, and the effectiveness of advertising. Middle age, middle-income customers living within 10 miles (16.1 km) of the farm comprised the largest percentage of customers surveyed at the PYO operations, while middle age, high-income individuals who also live within 10 miles of the fruit stand were the largest group of respondents at the fruit stands. PYO customers spent an average of $10.30, and prepick consumers spent an average of $9.40 per visit. Less than 23% of all the respondents said that advertising influenced their shopping decision while >77% indicated that any type of advertisement did not influence their decision. Overall, convenient location was easily the major reason that customers decided to patronize a specific direct market outlet while personal referrals were second.
James P. Gilreath, Bielinski M. Santos, Joseph W. Noling, Salvadore J. Locascio, Donald W. Dickson, Erin N. Rosskopf, and Steven M. Olson
Field studies were conducted in three Florida locations (Bradenton, Gainesville, and Quincy) during 1998-99 and 1999-2000 to: 1) compare the performance of two transplant systems under diverse MBr alternative programs in `Chandler' strawberry (Fragaria ×ananassa), and 2) determine the efficacy of these treatments on soilborne pest control in strawberry. Fumigant treatments were: 1) nonfumigated control, 2) methyl bromide plus chloropicrin (MBr + Pic) at a rate of 350 lb/acre, 3) Pic at 300 lb/acre and napropamide at 4 lb/acre, 4) 1,3-dichloropropene (1,3-D) plus Pic at 35 gal/acre and napropamide at 4 lb/acre, 5) metam sodium (MNa) at 60 gal/acre and napropamide at 4 lb/acre, and 6) MNa followed by 1,3-D at 60 and 12 gal/acre and napropamide at 4 lb/acre, respectively. Strawberry transplants were either bare-root or containerized plugs. There were no significant fumigant by transplant type interactions for strawberry plant vigor and root weight per plant, whereas ring nematode (Criconema spp.) and nutsedge (Cyperus rotundus and C. esculentus) populations, and total marketable fruit weight were only infl uenced by fumigant application. The nonfumigated plots had the lowest strawberry plant vigor and root weight per plant in all three locations. In most cases, plant vigor and root biomass per plant increased as a response to any fumigant application. With regard to the transplant type, bare-root transplants had similar plant vigor as plugs in two of the three locations. Fumigation improved nutsedge and ring nematode control. All fumigants had higher early and total marketable yield than the nonfumigated control, whereas transplant type had no effect on total fruit weight.
Mark E. Herrington, Craig K. Chandler, Jennifer A. Moisander, and Claire E. Reid
There is a need in Queensland winter strawberry ( Fragaria × ananassa Duch.) production areas for a highly flavored, early-ripening cultivar to replace or be an alternative to ‘Kabarla’ ( Herrington, 1995 ). ‘Kabarla’ has benefited the
Karen L.B. Gast and James E. Pollard
Ryoichi Nakajima, Shungo Otagaki, Katsuhiro Shiratake, and Shogo Matsumoto
June-bearing commercial strawberries ( Fragaria × ananassa ) are preferable to everbearing ones for Japanese consumers due to their high quality. The June-bearing strawberry is typically a short day and low temperature (SDLT) type plant, and its
Youngjae Oh, Jason D. Zurn, Nahla Bassil, Patrick P. Edger, Steven J. Knapp, Vance M. Whitaker, and Seonghee Lee
The development of new strawberry ( Fragaria × ananassa ) cultivars with improved flowering, fruit quality, and disease resistance is an ultimate goal for fruit breeders worldwide. Selective breeding has resulted in tremendous crop improvement, but
Masanori Honjo, Susumu Yui, and Miyuki Kunihisa
The octoploid cultivated strawberry, Fragaria × ananassa Duch. (2 n = 8 x = 56), was derived from accidental hybridization between two American octoploid species, F . virginiana and F . chiloensis , during the early to mid-1700s ( Darrow