Progress 10/01/04 to 09/30/07
Outputs
OUTPUTS: During 2007, seven cultural practice experiments and ten variety trials with cut flowers were completed. The topping studies with snapdragons confirmed the 2006 results, showing that apex removal increased yield by 26 and 38 percent in spring field and fall tunnel experiments, respectively. Late flowering varieties were less responsive than early flowering lines. Topping experiments with lisianthus were also conducted in both field and high tunnel, and also increased yield if six nodes were left on the plants. In sunflower, topping produced multiple stems, each of which were much smaller than the plants that had not been topped. Spacing the plants farther apart (12 x 12 in. vs, 9 x 9 in.) counteracted this trend to some extent, and may be necessary to produce sunflowers with consumer appeal. Investigations of the daylength response of sunflowers were continued, with the screening of 16 cut flower varieties for sensitivity to 12 or 16 hours daylength in the first three weeks
after emergence. Six varieties showed no response in flowering time or plant size, four had a slight short-day reaction, and five were classed as sensitive short day types. The latter flowered 18 days later in long-day conditions, and the plants were 45 in. tall, compared to 28 in. for the short-day plants. Two trials to pin down the exact time of daylength sensitivity in sunflower indicated that plants reacted most strongly when exposed to the critical daylength during week 2 after emergence, but this will need to be verified with additional work. Some sunflower varieties readily lose their petals if these are disturbed by brushing, even if the flower has just opened. This petal loss greatly detracts from flower appearance. An objective test was developed that measures the force required to pull a petal from the flower receptacle. Variety comparisons found clear differences, with Moulin Rouge, Strawberry Blonde and Procut Bicolor most susceptible to petal loss, and Sunrich Orange and
Procut Lemon most resistant. In previous years, variety trials with delphinium have suffered from a heavy loss of plants due to a severe root disease. Neither straw mulch nor silver color plastic mulch improved plant stands over the standard black plastic, but the variety Aurora White was reduced to a 33 percent stand at the end of the season, compared to 50 and 59 percent for Guardian Blue and Candles White Shades, respectively. Cut flower variety trials were conducted with lisianthus, ageratum, dianthus, gomphrena, larkspur, salvia, scabiosa, statice, ornamental kale and ornamental peppers. Many of the entries were provided by the national cut flower trial of the Association of Specialty Cut Flower Growers, and the results will be reported in their quarterly publication. New lines of lisianthus were particularly interesting, with new flower colors, including light brown, and a much smaller flower size showing promise.
PARTICIPANTS: There was no change in the participants in the project. In early April 2007, Pritts and Wien provided training in high tunnel management to growers and extension staff in four locations in Northern New York. The presentations, and tours of growers' tunnels, were arranged by Ms. Anita Deming and Amy Ivins, Cornell Cooperative Extension, Essex County.
Impacts
The results of our sunflower daylength sensitivity work have been publicized through articles in trade journals and at extension conferences visited by cut flower growers in New England and the mid-Atlantic states. As a result, flower seed catalogs are slowly correcting their information on daylength response, although some have so far not done so. We now have sufficient information on our topping trials to publicize this work in trade journals and in conferences. The technique is simple, and gives important benefits of spreading the flower harvest and increasing yield. Now that a simple objective test for petal loss in sunflower has been developed, there is a big opportunity to test for ways of arresting petal loss in susceptible varieties. Additional research will also help to provide an understanding of the link of petal removal force and flower vase life. The results of the variety trials are also publicized at extension meetings, and acquaint growers and the
public about the particular flower species, as much as the specific variety. There is considerable interest in the use of high tunnels to grow high value horticultural crops, and cut flower species are part of that interest. High tunnel construction and use for horticultural crops has been a popular topic at a number of extension meetings, and that interest is likely to continue.
Publications
- Wien, C. 2007. Day-neutral sunflowers: Do they exist, and what difference does it make? The Cut Flower Quarterly 19(1):48-49.
- Wien, C. 2006. Can we grow cut flowers with longer stems? The Cut Flower Quarterly 18(3):32-33.
- Wien, C. 2006. Growing Black-eyed Susan and sunflower out of season. Growing for Market 15(6):17-18.
- Wien, H. C. 2007. Book review: Crops and Environmental Change: An Introduction to Effects of Global Warming, Increasing Atmospheric CO2 and O3 Concentrations, and Soil Salinization on Crop Physiology and Yield. HortScience 42(7):1749.
- Wien, C. 2007. Floral crop production in high tunnels. Program and Abstracts, ASHS Annual Conference. HortScience 42(4):838.
- Wien, H. C. 2007. Increasing snapdragon cut flower yields with early pinching. Program and Abstracts, Annual Conference. HortScience 42(4):1016.
- Lubag-Arquiza, A. and Wien, H. C. 2007. Treatments for producing potted Paeonia Paula Fay for Mothers Day and Valentines Day. Program and Abstracts, ASHS Annual Conference. HortScience 42(4):974.
- Wien, H. C. 2007. Effect of time, heat and light on sunflowers. Pages 101-102 in Proc. Mid-Atlantic Fruit and Vegetable Convention, Hershey PA.
|
Progress 01/01/06 to 12/31/06
Outputs
Research continued on climate control in high tunnels (unheated polyethylene-covered greenhouses). In 2 tests within one high tunnel, we tested the effect of four low tunnel materials covering cut flower crops, on temperatures in spring and fall during periods of frost outside the high tunnel. Clear polyethylene, spunbonded nylon and greenhouse shading fabric all elevated minimum temperatures by 3 to 5 C when outside temperatures were -2 C, but if not removed on sunny days, clear plastic covers elevated temperatures around the plants to injurious levels. Variety trials of new cut flower cultivars were conducted on 10 species in the field, and 8 of these were also done in the high tunnel. Of the ornamental grasses tested, Feathertop Pennisetum was most productive and decorative, but produced a massive underground root. Lisianthus (Eustoma grandiflora) ABC 2-3 Green, and ABC White GX12444 were attractive and productive, Dianthus Sweet Scarlet had early stems with
brilliant red flowers, and Celosia Temple Belle New Scarlet was a productive cockscomb type. Cultural practice trials with cut flowers tested the effect of daylength during the first three weeks after emergence on earliness in flowering and plant and flower size of 25 sunflower varieties. Of these, 10 were day-neutral, 11 flowered more than 2 weeks earlier after short day treatment (12 hrs.) than if exposed to 16 hrs. in the first three weeks, and two flowered later under short day pretreatment than under long days. Apex removal to stimulate early branching was tested on sunflower, lisianthus and snapdragon. With sunflower, we confirmed that although topping at nodes 4 or 6 increased stems per plant to 3 to 4, the flower diameter was reduced by 50 percent, and vase life was decreased. In Lisianthus, stem yield was not significantly affected by apex removal, but stem length was increased by 15 percent. Topping at node 3 and 6 successively delayed the bulk of the flower harvest,
compared to the control, and may be a way of making flower harvest more uniform through the season. The greatest positive effect of apex removal was obtained with snapdragons. In 2 trials, one conducted in the high tunnel and one outside, stem number increased by 50 and 33 percent respectively when 6 nodes were left on the main stem. Stem length was unaffected or decreased by 10 percent by topping. Four cultivars were compared in the trial, and those in Flowering Groups 1, 2 and 3 gave higher yields, and responded to topping more than the Group 4 variety Rocket. The response of Rudbeckia hirta to time of planting was tested by sowing the seeds on four dates, and transplanting them either in the field or in a high tunnel (last two plantings). Sowing March 8 produced an average of 33 stems per plant over the season, about twice as many as the May 1 sowing. Planting a month later reduced yield to 7 stems per plant, and these were 17 percent shorter. A final planting in early July
produced only a few sessile flowers. A test of the photoperiod response of the three varieties on a controlled daylength bench in the greenhouse confirmed that they are obligate long day plants that fail to flower at a 12-hour photoperiod.
Impacts
High tunnels have aroused much interest among growers wishing to extend the growing season on valuable horticultural crops in spring and fall. Work on low tunnels is showing that such secondary covers over the crop in the tunnel can increase night temperatures and reduce high temperature stress on sunny days. The spun-bonded materials are the most promising in this regard, and will be tested in growers tunnels in 2007, and publicized at winter extension meetings. The results of our sunflower photoperiod work has been received with interest among seed companies and cut flower growers, for it helps in understanding growth responses of the crop when grown in high tunnels early in the growing season. The knowledge of the daylength response of specific cultivars will pressure seed companies to be more forthright about these characteristics to their customers. The work on topping of snapdragons confirms that productivity of this crop can be considerably increased by the
simple practice of encouraging early branching. A normal harvest of the main stem, in contrast, removes many potential branches. Topping has the added benefit of stimulating simultaneous flowering of several stems on each plant, thereby reducing harvest costs. Because of its sensitivity to daylength, Rudbeckia hirta performs best when it is allowed to produce an adequate vegetative frame before initiating flowers. With later plantings, the vegetative period is shortened, and productivity declines.
Publications
- Wien, H.C. 2006. Ethephon treatment may alleviate the suppression of female flowers of Cucurbita pepo under high temperatures. HortSci. 41:1421-1422.
- Wien, H.C. and T.A. Zitter. 2006. Initiating sudden wilt disorder in muskmelon with low light stress. Pages 60-64 in: Proceedings of Cucurbitaceae 2006. G.J. Holmes, ed. Universal Press, Raleigh, North Carolina.
- Vanek, S., H.C. Wien and A. Rangarajan. 2005. Time of interseeding of lana vetch and winter rye cover strips determines competitive impact on pumpkins grown using organic practices. HortSci. 40:1716-1722.
- Vidal, M. Das Gracas, D. DeJong, H.C. Wien and R.D. Morse. 2006. Nectar and pollen production in pumpkin (Cucurbita pepo L.). Revista Brasil. Bot. 29:267-273.
- Wien, H.C. 2006. Sheltering cut flower plants to increase stem length. (Abstract only). HortSci. 41:1066.
- Wien, H.C. 2006. Producting cut flowers in high tunnels and open fields. (Abstract only). HortSci. 41:1067.
|
Progress 01/01/05 to 12/31/05
Outputs
During the 2005 growing season, 4 species of flowers grown for use as cut flowers were grown in a high tunnel, and in the open field, comparing the performance of a total of 29 varieties. Most noteworthy were ABC 2-3 Blue, ABC 3-4 Rose and Echo Champagne lisianthus, Summer Dafne and Summer Helios trachelium and Flamingo Salmon godetia. Subjecting Sunrich Orange sunflower to 12 instead of 16 hours daylight during the first 3 weeks of seedling growth advanced flowering by 3 weeks, and resulted in 75 instead of 125 cm stem length. Since natural daylengths are short during early spring plantings, using photoperiod sensitive varieties such as this one could lead to earlier harvests. With many flower species, stem length at harvest is not sufficient to satisfy consumer expectations. In a field trial, we found that growing lisianthus, trachelium and Rudbeckia Prairie Sun in a 50 pct shade canopy increased stem length by 20 pct, but stems harvested reduced by 32 pct. Erecting
a side curtain of the same material to protect against wind resulted in a 10 pct increase in stem length, without decreasing yield. Snapdragon varieties used as cut flowers are classified according to their adaptation to winter, summer or intermediate conditions. To determine which types are best suited to early or late high tunnel production in New York State, 5 varieties spanning these types were transplanted in mid-April, late July or mid-August in our high tunnel, and outdoors in mid-May. Winter types produced similar yields in the April and July plantings, while the summer types had significantly decreased yields in the later planting. Both types were inhibited from flowering during August and early September by high temperatures, but the winter types resumed production more quickly than the summer varieties. Rudbeckia hirta is a short-lived perennial that produces attractive, long-lived blooms in the first year. The varieties most valuable as cut flowers are obligate long-day
plants. A time of planting study conducted outside and in the high tunnel indicated that sowing the photoperiod-sensitive variety Indian Summer in early March for transplanting in mid-May yielded 13.5 stems per plant compared to 4 stems when planted 2 months later. Many plants from a July 1 sowing did not flower. Goldilocks, when planted on these same dates, produced a more consistent yield, but flower size and stem length were not adequate for use as a cut flower. Removing the growing point of cut flower seedlings in the preflowering stage to force early branching is a common strategy to increase yield. When 2 sunflower varieties were topped to leave 4 or 6 nodes, there was an increase in stem numbers, but the results varied with the variety. In the earlier Procut Orange, many of the resulting flowers were small and misshapen. In Sunrich Orange, stem yield increased by 211 and 300 pct, and the size and attractiveness of the flowers was not adversely affected. A similar study with
lisianthus increased stem yield by an average of 36 pct in 2 varieties, without negatively affecting stem length or first harvest dates.
Impacts
The testing of new varieties of cut flowers is part of a national trialing system organized by the Association of Specialty Cut Flower Growers, and the results are nationally publicized to members. In addition, the encouraging performance of relatively less known crops like Trachelium, publicized through ASCFG and locally will increase production of this crop. Our tests of the photoperiod response of sunflower contradict the claims of several seed companies, and will guide growers in more predictable ways of growing this crop. The use of 50 percent shade to increase stem length has been shown by our research to depress yield too much, but use of side curtains to reduce wind-induced plant movement is practical, and can be easily implemented. Extending the research on snapdragons from greenhouse to production in tunnel and field indicates that the earliness and productivity of the winter greenhouse types could be useful in summer planting for fall harvest. This may be
even more important in milder climate zones. The simple process of plant topping appears to be a useful and simple way of increasing yield, but in sunflower, some varieties suffer adverse effects on flower appearance. With lisianthus, the results were encouraging and warrant additional work. The results of these trials have already been shared with growers at a New England regional extension conference in December 2005, and will be on my website.
Publications
- No publications reported this period
|
Progress 01/01/04 to 12/31/04
Outputs
Cut flower variety trials were conducted in the field and in a polyethylene-covered high tunnel to determine which varieties are adapted to New York conditions, and which show enhanced earliness and flower quality when grown in the tunnel. Nine species were grown in the tunnel and outside: cockscomb celosia, foxglove, dianthus, ornamental kale, lisianthus, matricaria, snapdragon, sunflower and zinnia. All reached harvest stage one week to one month earlier in the tunnel than outside. Celosia and lisianthus produced significantly taller flowers in the tunnel, a desirable attribute. Flower numbers per plant of lisianthus were increased from 3.5 outside to 4.6 in the tunnel, but in all other species except sunflower and kale, branching was suppressed by an average of 34 percent in the tunnel. Shading trials were conducted both in the tunnel and outside to determine if reduction in irradiance and alteration in light quality could enhance stem length of salpiglossis,
Rudbeckia, lisianthus and Trachelium cut flowers. In the tunnel experiment with salpiglossis, stem length was increased by 13 and 25 percent for black and red shade netting that reduced irradiance by 30 percent, respectively. In the field trial, stem length of the three flower species were increased by 6, 11 and 17 percent for plants under 30 percent black, 30 percent red and 50 percent red netting, respectively. The shade treatments reduced stem number per plant by 26, 11 and 27 percent for the 3 shade treatments, respectively. The results show promise for use of the red colored shade netting as a means to increase stem length without use of growth-enhancing chemicals. When Rudbeckia hirta var. Prairie Sun was planted in spring and harvested for cut flowers, it continued to flower all season long. A second planting sown in June 29 and transplanted to the tunnel Aug. 29 failed to flower, but remained vegetative. Suspecting that the daylength may have been too short to induce flowering
in the second planting, additional plants were grown at 12 hour or 16 hour photoperiods in a greenhouse. The plants in 12 hours stayed vegetative, whereas those in 16 hours flowered. When plants from the 16 hour treatment were transferred to the 12 hour daylength, they continued to produce flowers, confirming the result of our field observations that Rudbeckia hirta is induced to flower by long daylengths, but once induced, will continue to flower even if daylengths decrease.
Impacts
The current project marks the start of a significant effort in the area of cut flower research and extension at Cornell. The program is too new to have generated publications, but a field day was held during the summer to show the trials to 75 growers and extension personnel. During this winter, I will be giving talks at four extension meetings on the results and future plans of our research.
Publications
- No publications reported this period
|
|