Pecan (Carya illinoinensis) cultivars are commercially propagated by grafting and budding. The whip graft, bark graft and four-flap graft, the most frequently used techniques for pecan grafting, require dormant scions, collected and stored for 60 to 120 days before the spring grafting season. Poor graft success is sometimes attributed to poor handling and storage of the scionwood. Moisture content of packing material, sealing cut ends of the scions with wax, and use of polyethylene bags was evaluated in 1998 and 1999. Scions were collected in early February each year, and stored for 60 to 70 days in a household refrigerator at 2 °C (35.6 °F) under different treatment regimes. Scion viability was tested by bark grafting on limbs of mature pecan trees. Moisture of the scions was affected each year by the amount of water added to packing material and by sealing the cut ends, but the differences did not impact graft success. In 1998, graft success rate was equally good among scions stored in polyethylene bags with different amounts of added moisture, whether cut ends were sealed or not. Graft success in 1999 was affected by an interaction of sealing the cut ends, packing material and location of grafting.
Monte L. Nesbitt, William D. Goff and Larry A. Stein
Monte L. Nesbitt, Larry Stein and William D. Goff
Pecan is a difficult species to propagate by grafting. The whip graft, bark graft, and four-flap graft, the most often-used techniques for pecan grafting, require dormant scions, collected and stored for 60 to 120 days prior to spring-season grafting. Poor graft success is often blamed on handling and storage environment of the scionwood. Moisture content of packing material, waxing of cut ends, and use of polyethylene bags was evaluated in a controlled experiment in 1998 and 1999. Scions were cut in early February each year, and stored for 60 to 70 days in a household refrigerator under different treatment regimes. Scion viability was tested by bark grafting mature pecan trees in Fairhope, Ala., and Uvalde, Texas. In 1998, graft success rate was equally good among scions stored in polyethylene bags with different amounts of added moisture, whether cut ends were waxed or not. Moisture loss of the scions during storage was affected each year by the amount of water added to packing material and by waxing the cut-ends, but the differences did not impact graft success. An interaction of not waxing the cut ends and very wet packing material reduced graft success at Fairhope, Ala., but not Uvalde, Texas, in 1999.
Larry A. Stein, Jerry M. Parsons and R. Daniel Lineberger
Daniel I. Leskovar, Larry A. Stein and Frank J. Dainello
The objective of this work was to determine the effect of within-row plant spacing and mulching on growth, quality, and yield of an experimental semi-savoy spinach (Spinacea oleracea L.) genotype `Ark-310' to produce a high quality fresh market product. Within-row spacings were 15 and 25 cm, and mulching treatments were bare-soil and black polyethylene mulch. Plants were destructively sampled weekly (1995-96) or bi-weekly (1997-98) for leaf area (LA), leaf number, leaf dry weight (LDW) and root dry weight (RDW) measurements. Plants grown on plastic mulch at 25-cm spacing had greater LA, LDW, and RDW than when grown at 15-cm spacing on mulch or bare-soil. Leaf number and specific leaf area (LA/LDW) were less affected by either spacing or mulching. The amount of soil on harvested leaves was lower on plants grown on plastic mulch in both years. In one year, total yields (MT/ha-1) were 42% higher at 15-cm than at 25-cm plant spacing, while mulch increased yields by 20%, independently of plant spacing. These effects were not evident in the year with higher rainfall (1997-98).
Frank J. Dainello, Larry Stein, Guy Fipps and Kenneth White
Competition for limited water supplies is increasing world wide. Especially hard hit are the irrigated crop production regions, such as the Lower Rio Grande Valley and the Winter Garden areas of south Texas. To develop production techniques for reducing supplemental water needs of vegetable crops, an ancient water harvesting technique called rainfall capture was adapted to contemporary, large scale irrigated muskmelon (Cucumis melo var. reticulatus L.) production systems. The rainfall capture system developed consisted of plastic mulched miniature water catchments located on raised seed beds. This system was compared with conventional dry land and irrigated melon production. Rainfall capture resulted in 108% average yield increase over the conventional dry land technique. When compared with conventional furrow irrigation, rainfall capture increased marketable muskmelon yield as much as 5355 lb/acre (6000 kg·ha-1). As anticipated,the drip irrigation/plastic mulch system exceeded rainfall capture in total and marketable fruit yield. The results of this study suggest that rainfall capture can reduce total supplemental water use in muskmelon production. The major benefit of the rainfall capture system is believed to be in its ability to eliminate or decrease irrigation water needed to fill the soil profile before planting.
James N. Moore, John R. Clark, James Kamas, Larry Stein, Friench Tarkington and Martha Tarkington
Wayne A. Mackay, Steve George, Jerry M. Parsons, Greg Grant, Tim D. Davis and Larry Stein
Wayne A. Mackay, Steve George, Tim Davis, Mike Arnold, Dan Lineberger, Jerry Parsons and Larry Stein
The Coordinated Educational Marketing Assistance Program (CEMAP) is one of the oldest marketing assistance programs for ornamentals in the United States. The goal of this program is to identify outstanding plants for Texas and to provide support for the nursery industry, thereby making plants with superior performance available to the people of Texas. The CEMAP program is a cooperative effort between the Texas nursery industry and Texas A&M Univ. The CEMAP Executive Board has eight individuals representing extension, research, and teaching plus two administrative liasions and the Industry Advisory Board has ≈50 members from all segments of the ornamentals industry in Texas. Funding for the CEMAP program comes from direct industry support and from the public through the sale of plant tags or other promotional materials which bear the Texas Superstars logo. The logo is trademarked and licensed to printing companies who handle the administration of royalties to the program. The Executive Board makes the final decision about which plants are designated Texas Superstars. Promotional support for the plants is provided by CEMAP through point of purchase materials and publicity through print, radio, and television. In addition, the Texas Nursery and Landscape Association in cooperation with the Texas Department of Agriculture are conducting a publicity campaign to inform the public about Texas Superstars.
Dan Chapman, G.R. McEachern, Laurence Sistrunk, John Lipe, Larry Stein and J.B. Storey
Five Texas orchards were selected in Spring 1993 in commercial pecan counties for testing three types of soil aeration equipment. Mechanical aeration spikes were either 20 or 46 cm long, and a pneumatic spike was 20 cm long. The mechanical spikes are on a rolling cylinder that can be manufactured in sufficient lengths to fit the tree spacing in different orchards. The pneumatic probe is manually inserted into the soil so that a quick burst of 130-psi air can be delivered to effect soil profile fracturing. The fourth replicated treatment was an nontreated control. There were no differences in trunk diameter increases and yield in 1993 between May-applied replicated treatments. The May treatments and November measurements will continue for two more years to allow for differences in soil aeration to influence growth and yield. Shoot growth measurements will be taken in Spring 1995. Irrigation water has penetrated the soil under aerated trees more readily than in nonaerated controls.
Michael A. Arnold, R. Daniel Lineberger, Tim D. Davis, Steven W. George, Wayne A. Mackay, Greg D. Grant, Jerry M. Parsons and Larry A. Stein
Plant trialing and marketing assistance programs have become popular in recent years with several state and some regional programs emerging. Successful implementation requires considerable labor, facilities, and monetary resources for evaluation of large numbers of taxa over several years to ensure that plants are well adapted to the region of interest. Research and development funds, dedicated facilities, and cooperator commitment to trialing programs can be limiting during the early years of the programs. Involvement in plant trialing programs allows students to be exposed to plot layout planning, statistical design, plant maintenance, data collection and analysis, and professional communication of trial results. Construction of facilities for conducting plant trials, growing plants for use in trials, trial installation, and maintenance of plants all provide practical hands-on horticultural training. Replicated plant trials provide the latest information on regionally adapted taxa for inclusion in classroom instruction and publications. Plant trialing programs benefit from labor assistance, development of dedicated facilities, and the opportunity to share equipment and supplies among teaching, trialing, and student research projects.