. High salt concentrations in soil solution can negatively influence seed germination, growth, flowering, and fruit set, decreasing yield and the quality in crops ( Arora et al., 2008 ). Strawberry cultivation (with 250,000 t production) ( FAO Food and
Huseyin Karlidag, Ertan Yildirim, Metin Turan, Mucahit Pehluvan and Figen Donmez
James F. Hancock, Chad E. Finn, James J. Luby, Adam Dale, Pete W. Callow and Sedat Serçe
The founding genetic base of the commercial strawberry, Fragaria × ananassa Duchesne in Lamarck, is limited. It originated ≈250 years ago when a few clones of South American F. chiloensis chiloensis (L.) Miller subsp. chiloensis forma
Melinda A. Miller-Butler, Barbara J. Smith, Brian R. Kreiser and Eugene K. Blythe
In the southeastern United States, anthracnose diseases of commercial strawberry ( Fragaria × ananassa Duch.) are caused primarily by three Colletotrichum species: C. acutatum, C. fragariae , and C. gloeosporioides ( Maas, 1998
Vida Chalavi, Zohreh Tabaeizadeh and Pierre Thibodeau
providing the in vitro strawberry plants. Technical assistance of Johanne Caron and Lucie Laverdière from Hort-protection Inc. as well as M. François Charrier from Institut de Recherche et de Développement en Agroenvironnement (IRDA) is acknowledged
N.F. Gariglio, R.A. Pilatti and B.L. Baldi
In Santa Fe, Argentina, strawberries (Fragari ×ananassa Duch.) are cultivated in the area of Coronda where N fertilization usually exceeds crop requirements. The objective of this work was to test four types of fertilization methodology to optimize fertilizer use efficiency. Experiments were carried out at the horticultural center of the Facultad de Agronomía y Veterinaria, in Esperanza, Santa Fe, 31.15° S latitude, on a typical argiudol soil. `Chandler' was planted 13 Mar. 1996. Nitrogen demand was related to the dry matter production with N content decreasing to increment of biomass (W), soil N mineralization was estimated according to the program EDAFO version 3. Using previous data, a monthly balance was calculated and four treatments were devised: control (T0) = without fertilization; treatment 1 (T1) = N fertilization covering the accumulated monthly deficit, 53 kg·ha-1 (47 lb/acre); treatment 2 (T2) = N fertilization covering the monthly deficit 66 kg·ha-1 (58 lb/acre); treatment 3 (T3) = N fertilization covering the total crop demand 117 kg·ha-1 (104 lb/acre). All N treatments significantly increased yields over the control. Yield increased to increasing N rates from 0 to 53 kg·ha-1. This response was due to an increase in fruit number but not in fruit weight. High N rates promoted runner growth without increasing fruit yield. The use N balance method for strawberry fertilization showed satisfactory results. Accumulated N balance (T1), required the least amount of N fertilizer while producing good yield, thus it should be the method adopted to reduce costs and environmental risks of N fertilization.
Lei Jiajun, Li Yuhua, Du Guodong, Dai Hanping and Deng Mingqin
A natural strawberry genotype, `Jilin 4', was collected from the Changbai Mountains located in Gongzhuling Region, Jilin Province, Northeast China. It was identified as a pentaploid (2n = 5x = 35) by counting the chromosomes of the root-tip cells. Natural pentaploid strawberries have not been reported as originating in China or outside of California in the U.S. Jilin 4 was the most vigorous genotype among representatives of all 15 wild species of Fragaria and more than 60 cultivars of F. ×ananassa in a common garden. The size of its flowers and anthers were similar to those of cultivars and it produced abundant runners. The pollen was viable, but the pistils were sterile. It appeared to be drought and cold tolerant, but showed symptoms of local virus infection. There are three possible origins of Jilin 4, which are discussed in this report.
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
James A. LaMondia, Richard S. Cowles and Lorraine Los
Surveys mailed to strawberry growers in 1999 determined the state of nematode and root weevil awareness and practices for their management. Based on the survey response, 41 fields representative of various practices were selected for sampling throughout Connecticut. Adult black vine weevils (Otiorhynchus sulcatus) were found in only 3 fields, but notched leaves characteristic of their feeding were found in 40 fields, indicating a greater prevalence than perceived by growers. The percentage of notched leaves was positively correlated with years in production, suggesting that it took some time for the flightless weevils to migrate into and to increase to damaging numbers in fields. In fields older than 2 years, bifenthrin insecticide reduced leaf feeding compared to untreated fields or to fields treated with endosulfan or azinphos-methyl. Lesion nematodes (Pratylenchus penetrans) were detected in 31 fields and were present in about 58% of plants. When present, nematode numbers were greater in the margins of poor areas than in adjacent healthy plants (735 vs. 428 per g root, respectively). Lesion nematode numbers were also greater in replanted strawberries than rotated fields (760 vs. 304, respectively). Soil fumigation with methyl bromide, but not methyl dithiocarbamate or the combination of 1,3-dichloropropene and chloropicrin, reduced nematode densities in the following strawberry crop. Based on an economic model, nematodes reduced accumulated profit over 4 fruiting years by more than the percent loss of fruit yield. Beneficial insect pathogenic nematodes, predominantly Heterorhabditis bacteriophora and Steinernema feltiae, were found in 75% of fields to which commercially obtained nematodes had been applied, and to 14% of the remaining fields. Presence of naturally occurring insect pathogenic nematodes in strawberry fields may control root weevil populations and lead to more years of productivity.
Carl H. Shanks Jr. and Patrick P. Moore
More than 170 clones of Fragari ×ananassa Duch., F. chiloensis (L.) Duch., and F. virginiana Duch. were tested for resistance to the twospotted spider mite (Tetranychus urticae Koch). Twenty-seven clones had >75% fewer mites than did F. ×ananassa `Totem', a susceptible clone. About two-thirds of the clones also were tested for resistance to the strawberry aphid [Chaetosiphon fragaefolii (Cockerell)]. Survival and reproduction was significantly lower on two clones each of F. ×ananassa and F. virginiana than on `Totem'.
J. Scott Cameron and Carol A. Hartley
Washington Strawberry Commission and the Kay Mukai Research Foundation, Watsonville, Calif. The technical assistance of D.R. Mittelstadt and M.P. Rogers during the course of this study is greatly appreciated. The cost of publishing this paper was defrayed in