Search Results
The phosphorus content is usually high in soils on which strawberry production occurs in west central Florida because of moderate P levels in the virgin soil and yearly applications of P by the growers. A P rate study was conducted to test the calibration of P for strawberry nursery production, and a randomized complete block design with four replicates was used. Rates of 0, 11, 22, and 33 kg/ha P were applied to a Seffner sand which had an initial soil P level of 86 mg/kg using the Mehlich II soil extractant. Soil tests routinely show P soil concentrations up to 250 mg/kg or greater with 86 mg/kg rated in the high range. In this study the P applied to the beds was cultivated into the soil and six plants of two strawberry clones (Fl 87-210 and Fl 85-4925) were set in each plot on 28 May 1991. All nutrients except P were applied as needed during the season. Leaf P content of daughter plants on 20 Aug 1991 varied from 0.23 to 0.25% among P treatments and were not different because of P rates. All marketable size daughter plants were harvested on 8 Oct 1991. The number, total wt, and average wt of daughter plants were not different because of applied P rates.
Development of new strawberry cultivars for winter fruit production in Florida entails growing of hybrid seedlings in a nursery in the summer of the first year for runner plant production. Two runner plants are taken from each seedling and planted in the fruiting field in the fall. An experiment was conducted to see if it is possible to predict which genotypes in the nursery will have the highest early season fruit yield. Seedlings from 24 families from a 6 × 4 factorial mating design were grown in a nursery. From each family, daughter plants of 20 seedlings with the highest vigor and 20 randomly picked seedlings were then evaluated in the fruiting field. Plants from selected (high-vigor) seedlings were more vigorous, but had fewer crowns and runners, than unselected plants. More inflorescences were counted in selected plants than in unselected plants during the second week of January. This could account for higher early yield (yield at the end of January) and total yield (yield at the end of March) in selected than in unselected plants.
Abstract
Studies were conducted on the feasibility of shortening the evaluation period of highbush blueberry (Vaccinium corymbosum L.) selections by propagating by softwood cuttings taken from each of the single-plant selections at the time of fruit evaluation row the following spring. Softwood cuttings were taken from a single plant of 5 early, 5 midseason, and 5 late ripening selections in June, July, and August. July cuttings (60%) rooted better than June (37%) and August (31%) cuttings. Early selections (34%) rooted about the same as midseason (32%) and late (35%) selections. The earlier the cuttings were potted, the larger the root system they developed before frost when grown in an unheated greenhouse. None of the rooted cuttings potted 30 Sept, developed root systems large enough to survive field planting. Supplemental heat and light after potting increased root growth of plants potted 25 Aug. but not those potted 10 Sept. Eighty percent of the plants transplanted to the field survived.
Abstract
Guard cells tended to be shortest for diploid species and longest for hexaploids, but there was so much plant-to-plant variation both within ploidy levels (diploid, tetraploid, hexaploid) and within species that guard cell length was not a reliable indicator of ploidy level of individual plants.
During 2 seasons, defoliated and non-defoliated strawberry plants were evaluated for their fruiting response using the annual hill cultural system in Dover, FL. Partially dormant Canadian grown `Chandler' and non-dormant locally grown FL breeding line 79-1126 were grown the first season. Locally grown `Dover' was added the second season. Total yields of all clones were reduced with foliage removed. Monthly yields were reduced the first season with FL 79-1126 defoliated plants, but only the April yield of defoliated `Chandler' was reduced. December, January, March, and total yields of defoliated plants from all clones were reduced the second season. Average seasonal fruit weight was reduced the second season with locally grown defoliated plants. During the second season the percent marketable fruit of `Chandler' and FL 79-1126 was greater with the defoliated plants.
During 2 seasons, defoliated and non-defoliated strawberry plants were evaluated for their fruiting response using the annual hill cultural system in Dover, FL. Partially dormant Canadian grown `Chandler' and non-dormant locally grown FL breeding line 79-1126 were grown the first season. Locally grown `Dover' was added the second season. Total yields of all clones were reduced with foliage removed. Monthly yields were reduced the first season with FL 79-1126 defoliated plants, but only the April yield of defoliated `Chandler' was reduced. December, January, March, and total yields of defoliated plants from all clones were reduced the second season. Average seasonal fruit weight was reduced the second season with locally grown defoliated plants. During the second season the percent marketable fruit of `Chandler' and FL 79-1126 was greater with the defoliated plants.
Florida-developed strawberry (Fragaria ×ananassa Duch.) clones or varieties grown in Florida nurseries and California-developed varieties grown in Canadian nurseries were evaluated in fruiting studies in Florida during four seasons. Transplants were defoliated so that 0%, 35%, 60%, or 87% of the foliage was removed. The Florida clones `Dover' and selection 79-1126 gave significant linear and/or quadratic early and total marketable yield responses to defoliation treatments for all seasons. The Canadian-grown clones `Chandler' and `Selva' gave similar responses during three seasons, but differences were not as great as for the Florida-grown clones. Many significant linear and quadratic responses in seasonal average fruit weight and plant size occurred for Florida-grown plants, but only one occurred with the Canadian-grown plants. Relative plant size at early and midseason decreased with greater defoliation.
Strawberry (Fragaria × ananassa Duch.) was grown for two seasons on a fine sand soil to study the plant and fruiting response of three cultivars to K rates of O, 56, 112, 168, and 224 kg·ha-1. `Dover' total fruit yields increased linearly with rate both seasons while the maximum March yield the first season was with 170 kg K/ha. April yields increased linearly with K rate the first season. `Tufts' and `Chandler' responses to K rates were not consistent for monthly or total fruit yield. The average fruit weight of `Dover' and `Tufts' decreased linearly with increasing K rate for March and for the season in 1984, while `Dover' gave a positive linear average fruit weight response to K rate during Apr. 1986. `Dover' leaf K decreased from December to February, and K deficiency symptoms were expressed by February in treatments receiving lower rates of K. Leaf K concentrations of `Dover' correlated well with K rate.
Progeny testing, both formal and informal, has been a component of the University of Florida strawberry breeding program. Informally, the potential of numerous parental combinations has been assessed by growing small populations of each combination, and then ranking these populations according to visual impression. Formal progeny testing, where variables are measured on seedlings in a replicated measurement block, was used during the 1987-88 season. Several families were identified as promising, based on an analysis of yield, fruit size, firmness, and appearance data.