From 1988 to 1990, the fall fruiting raspberries Heritage, Perron Red, Autumn Bliss and 3413-12 were field evaluated under two cultural systems: conventionnal production and production under plastic tunnel. The plastic tunnel was in place over 4 rows from early September to late October without supplemental heating. Compared to the conventionnal system, the tunnel contributed to a lengthening of 1 to 4 weeks in the fruiting period 2 years out of 3. In spite of the higher day temperatures, the rate of fruit ripening was not increased under the tunnel but fruit size was increased slightly. However, the latter did not translate in higher yield per day since fruit number decreased under the tunnel. Total yield increased only one year when the first killing frost occurred a full month before the second one. Generally, night temperatures were as low in the tunnel as those outside.
Michel Lamarre and Michel J. Lareau
Michel Lamarre and Michel J Lareau
A 3-year study was carried out on the use of row covers as a substitute to straw for winter protection of five strawberry cultivars. Seven cover treatments were tested: “Agronet” removed on May 2, 12 and 19; “Kimberlay farms” removed May 19; perforated polyethylene removed May 16; conventionnal straw mulch removed in mid-April, and no row cover protection. Row covers advanced first harvest for all cultivars. There was a 10-day gain in earliness with perforated polyethylene followed in decreasing order by “Kimberley farms”, “Agronet”, straw mulch, and no protection. Treatments favoring early yields tended to shorten the period of production and to reduce total yield. Of the “Agronet” treatments, the May 12 removal increased the yield for the first 4 harvests compared to the May 2 and May 19 removals.
Michel J Lareau and Michel Lamarre
A new raspberry production system has indicated the feasibility of marketing fresh fruit during August and September, 60-90 days after planting. Full length dormant canes planted late and managed similarly to the strawberry plantings using “waiting bed” plants produced more than 6.0 t/ha. Large canes (>13 mm) produced more laterals and 3 times more fruit than small ones but fruit size was the same. There was little difference between the June 1 and June 20 plantings and `Killarney' outyielded `Festival'. In spite of higher establishment costs, it appears that the higher value for the fruit marketed in late summer and the possibility of using this system for the establishment of a new planting would justify its use.
Shahrokh Khanizadeh, Michel Lareau and Buszard Buszard
`Oka' is a mid-season, high yielding June-bearing strawberry cultivar with excellent productivity, good fruit color, flavor and firmness. It is recommended for fesh market and pick your own for the Southern Québec region. `Oka' plants are of medium size, and vigor with five to seven inflorescences per mother plant. They can tolerate winter temperatures of -25 C. Inflorescences are held erect on medium to long peduncles during bloom, and become semi-erect as fruit mature. Fruits are large, wedge shape and the calyces are semi-reflexed. Skin is moderately shiny, light red at full maturity, and the flesh is light red. Fruit flavor is similar to `Bounty', `Chambly', `Glooscap' and `Sparkle'. Fruits are medium firm to firm, and can not be decapped as easily as `Bounty', `Chambly' or `Glooscap'. More than 50% of harvested fruit have long pedicels. Percent juice loss after thawing does not differ significantly from other popular cultivars. `Oka' has outyielded `Bounty', `Redcoat' and `Sparkle' at L'Acadie and `Bounty', `Glooscap', and `Veestar' in New Brunswick. Plants can tolerate the herbicide terbacil. No symptoms of powdery mildew or leaf scorch were observed during the course of its evaluation. However some symptoms of leaf spot were observed late in the season before the onset of dormancy. Preliminary studies show that `Oka' is resistant to races 2, 4, 5, 8, 9 and 10 of P. fragariae.
Shahrokh Khanizadeh, Michel J. Lareau and Deborah Buszard
Shahrokh Khanizadeh, Michel J. Lareau and Deborah Buszard
An experiment was conducted to evaluate the mechanical harvesting and processing suitability of four standard strawberry [Fragaria ×ananassa (Duch.)] cultivars (`Kent', `Glooscap', `Bounty', and `Midway') and the recent introductions `Chambly' and `Oka'. `Kent', `Glooscap', `Oka', and `Chambly' had the highest yields and heaviest fruit. Similar percentages of berries of all cultivars were destroyed by the harvester. `Oka' and `Midway' were not suitable for this type of mechanical harvesting due to their susceptibility to bruising during harvest. Based on total marketable fruit harvested mechanically, `Chambly' was the most and `Oka' was the least adapted cultivars for this particular harvester. `Chambly' and `Glooscap' were easiest to decap, followed by `Bounty', `Oka', and `Midway'. None of the cultivars tested were suited ideally for machine harvesting, and further breeding is required to produce well-adapted cultivars.
Shahrokh Khanlzadeh, Michel J. Lareau and Deborah Buszard
During 1987-90, nineteen strawberry cultivars and one selection from Agriculture Canada/McGill University were evaluated for their fruiting and other plant characteristics. Based upon an index of potential return which Integrates percent yield at each harvest date and total yield, the following cultivars listed in decreasing order of desirability (early productivity) are recommended: `Chambly', `Annapolis', `Honeoye', `Kent' and `Cavendish'. `Lina', `Lester', SJ83OR-2, `Bounty' and `Settler' have the most concentrated ripening period based upon an index of concentration. Highest yields were obtained with `Honeoye', SJ83OR-2, `Chambly', `Kent', Glooscap` and `Oka'. All had large, medium-firm fruit. Because of their tolerance to the herbicide terbacil and their large, medium-firm fruit, `Chambly', `Oka' and SJ830R-2 appear to be potential replacements for the commercial cultivars `Kent', `Honeoye' and `Glooscap' and are recommended for trials in Quebec. `Cornwallis', `Settler', `Midway', `Cavendish' and `Redcoat' had the lowest yield variability of the cultivars on trial.
Shahrokh Khanizadeh, Mamdouh A. Fanous, Michel J. Lareau and Deborah Buszard
Three mathematical indices were developed to estimate: a) potential for early dollar return or early ripening (IE), b) concentrated cropping (IC), and deviation or similarity of a genotype to known cultivars (ID). Early ripening genotypes with high yield early in the season will have larger IE values than late genotypes with lower yield early in the season. Genotypes with few harvests will have larger IC values than those requiring several harvests. The ID index helps to identify and group genotypes with similar characteristics. These indices condense large numbers of values or arrays of traits into single index values, thereby simplifying genotype comparisons.