Florida Agricultural Experiment Station journal series no. R-10140. I wish to thank Luci Fisher for her technical assistance; the Solid Waste Authority of Palm Beach County, Fla., for the compost product; and Lovell Farms, Miami, Fla., for the plant
Boyang R. Cao and Chih-Cheng T. Chao
in the collection of date palm cultivar samples. We also recognize partial financial support from the Univ. of California, Genetic Resources Conservation program.
Deepak K. Khandka, Ali Nejidat, Moshe Tal and Avi Golan-Goldhirsh
Several horticulturally important species are dioecious (e.g., pistachio, date palm, poplar, and others). It would be advantageous if the gender of a seedling could be determined at the vegetative stage. In this report, we present results of our search for molecular markers for sex differentiation in dioecious species. The method used was bulked segregant analysis of random amplified polymorphic DNA (RAPD) for sex. A male-specific marker fragment OPB01-1470 was obtained in Mercurialis annua. The sex linkage and characterization of this marker will be discussed.
Joseph DeFrank and Charles R. Clement
Pejibaye (Bactris gasipaes, Palmae) is being evaluated for heart of palm production in Hawaii. Yields and weed control were evaluated in response to: oryzalin (4.5 and 9.0 kg ai/ha), oxyfluorfen (0.6 and 1.2 kg ai/ha), paraquat (1.2 and 2.4 kg ai/ha) and woven black polypropylene mat. Four open-pollinated progenies from the Benjamin Constant population of the Putumayo landrace were used as replications. Paraquat was sprayed at 50 day intervals, while the preemergence herbicides were sprayed at 90 day intervals. Harvest started at 18 months after planting out, 17 months after treatment initiation. The polypropylene mat yielded the highest percent harvest (80%), followed by Oxyfluorfen (50%), paraquat (20%), oryzalin (12.5%). There were replication (genotype) effects that suggest varying tolerance to paraquat and oryzalin. Estimated palm heart yields (3731 plants/ha), corrected for % harvest, were highest with polypropylene mat (490 kg/ha), followed by oxyfluorfen 1.2 ai (425 kg/ha) and 0.6 ai (330 kg/ha). Paraquat severely inhibited growth of the suckers that assure future harvests. The performance rating of these weed control treatments was: mat = oxyfluorfen > oryzalin > paraquat.
Melinda S. Conner and Gerald Klingaman
Interiorscape conditions were used to compare plant growth and water use between a commercially produced medium with hydrophilic polymer and a traditional peat-lite medium. 15 cm pots of parlor palm and pothos were grown in either the medium with polymer or a peat-lite medium. Fertilizer treatments applied to both media included: 1.2 kg N/m3 Osmocote 14N-6.1P-11.6K and 500 ppm (mg/kg) N of Peter's 20N-8.7P-16.5K. Plant height, width, top fresh and dry weight, quality and foliage color were determined for parlor palm and top fresh and dry weight and quality were determined for pothos. Plants grown in the peat-lite medium receiving either liquid fertilizer or slow-release fertilizer were significantly greater in all parameters measured than those growing in the medium with polymer that received liquid fertilizer. Plants grown in the medium with polymer had greater growth and quality with the slow-release fertilizer than liquid fertilizer treatments. The number of days until watering was not extended in the medium with hydrophilic polymer.
Timothy K. Broschat
Spathiphyllum Schott. `Mauna Loa Supreme' and areca palm (Chrysalidocarpus lutescens H. Wendl.) were grown for 6 months in 3.5-liter containers using a pine bark–sedge peat–sand container medium or a native sand soil. Plants were fertilized with equivalent amounts of a 21N–3P–12K fertilizer applied weekly as a liquid, monthly as a soluble granular, bimonthly as a lightly coated controlled-release, or every 6 months as a heavily coated controlled-release fertilizer. All leachates were collected and analyzed weekly for NO3-N, PO4-P, and K. Amounts of all three nutrients leached per week varied considerably in response to fertilizer reapplications or high rainfall. Nitrate leaching generally decreased over time, PO4-P leaching increased, and K remained relatively constant. Shoot dry weights of spathiphyllum were equivalent for all fertilization methods, but areca palm shoot dry weights were highest with liquid fertilization and lowest with the soluble granular fertilizer. Nutrient leaching for all three ions was highest for the soluble granules and lowest for the two controlled-release formulations.
Jianjun Chen, Dennis B. McConnell, Cynthia A. Robinson, Russell D. Caldwell and Yingfeng Huang
Florida Agricultural Experiment Station journal series R-08799. The authors appreciate AllGro, Inc., West Palm Beach, Fla., Consolidated Resources Recovery, Sarasota, Fla., and Sumter County Solid Waste Facility, Fla. for providing composted
DeFrank and Charles R. Clement
Pejibaye (Bactris gasipaes, Palmae) is being evaluated for palm heart production in Hawaii. Counts of parasitic nematodes and yields at 18 months and weed control were evaluated in response to: Arachis pintoi, Cassia rotundifolia cv. Wynn, Desmodium ovalifolium, Chloris gayana, and woven black polypropylene mat. Four open-pollinated progenies from the Benjamin Constant population of the Putumayo landrace were used as replications. Twenty five percent of the plants were harvested, with means of 5, 20, 15, 15, and 70%, respectively. Individual heart weights did not vary significantly among treatments (mean = 169 g). Actual yields were significantly different, with means of 31, 125, 92, 99, and 440 kg/ha, respectively. All vegetative ground covers competed with pejibaye for nutrients, which explains the harvest percentages and yields. D. ovalifolium and C. gayana provided acceptable weed control. A. pintoi provided good ground cover, but reduced weed control.
Timothy K. Broschat and Kimberly A. Klock-Moore
Areca palms [Dypsis lutescens (H. Wendl.) Beentje & J. Dransf.], spathiphyllums (Spathiphyllum Schott. `Figaro'), ixoras (Ixora L. `Nora Grant'), tomatoes (Lycopersicon esculentum Mill. `Floramerica'), marigolds (Tagetes erecta L. `Inca Gold'), bell peppers (Capsicum annuum L. `Better Bell'), and pentas [Pentas lanceolata (Forssk.) Deflers. `Cranberry'] were grown in a pine bark-based potting substrate and were fertilized weekly with 0, 8, 16, 32, or 64 mg (1.0 oz = 28,350 mg) of P per pot. Shoot, and to a much lesser extent, root dry weight, increased for all species as weekly P fertilization rate was increased from 0 to 8 mg/pot. As P fertilization was increased from 8 to 64 mg/pot, neither roots nor shoots of most species showed any additional growth in response to increased P. Root to shoot ratio decreased sharply as P fertilization rate was increased from 0 to 8 mg/pot, but remained relatively constant in response to further increases in P fertilization rate.
John L. Cisar, George H. Snyder and Karen E. Williams
For only the second time, the United States will host The International Turfgrass Society's (ITS) International Turfgrass Research Conference (ITRC). The VII ITRC will be held July 18-24, 1993 at The Breakers in Palm Beach, FL. Since its inception, the ITS has been devoted to addressing problems that effect turfgrass and improving the standards of turfgrass science through international communication. The Conference will offer two symposia entitled “Pesticide and Nutrient Fate in Turfgrass Systems” and “Quantification of Surface Characteristics of Sports Fields”. Additionally plenary and volunteered oral and poster presentations on all topics of turfgrass science and related horticultural landscape management tours of the local horticultural industries will be offered. Volunteered papers will be published in a proceedings as either original research papers or as technical papers. Papers submitted as original research will undergo refereed peer review prior to acceptance. See poster for further details or contact authors at above address (phone: 305-475-8990).