known to transmit 111 virus species ( Jones, 2003 ). Six sweetpotato whitefly-transmitted begomoviruses of melon ( Cucumis melo L.) have appeared in commercial melon fields in the southwestern United States, western Mexico, and Central America since
James D. McCreight, Hsing-Yeh Liu, and Thomas A. Turini
Walter F. Ray, Geno A. Picchioni, Dawn M. VanLeeuwen, and Ryan M. Goss
semiarid conditions of the southwestern United States. Rather, research has been confined largely to the cool-season and transition zones. Two studies on ‘Kentucky 31’ demonstrated an inverse relationship between mowing height and shoot development
Genhua Niu, Denise S. Rodriguez, and Mengmeng Gu
As urban population increases and fresh water supply is diminishing in the southwestern United States, many municipalities have encouraged using reclaimed water (treated municipal effluent, also called recycled water) for landscape irrigation. In
Seiichi Miyamoto and Monte Nesbitt
Pecan is among the most salt-sensitive tree crops currently grown in the southwestern United States. The threshold soil salinity in the main root zone for tree growth appears to be around 2.0 dS·m −1 in the soil saturation extract when sodium (Na
Anne M. Lockett, Dale A. Devitt, and Robert L. Morris
and perceptions toward using reused water for irrigation in the southwestern United States HortTechnology 14 1 7 Jiang, H. Fry, J.D. Wiest, S.C. 1998 Variability in turfgrass water requirements on a golf
Brian J. Schutte, Abdur Rashid, Israel Marquez, Erik A. Lehnhoff, and Leslie L. Beck
historically found in sandy arroyos in the southwestern United States ( Abrams, 1951 ; Wooten and Standley, 1915 ) and is now verified in 15 states, usually in geomorphic settings where soil is saturated or flooded at least seasonally ( U.S. Department of
Brian A. Kahn
Paprika pepper (Capsicum annuum L.) plants were subjected to a single, destructive harvest in either October, November, or December to determine an optimal month for once-over harvest. Studies were conducted at two locations in Oklahoma each year for 2 years. Total and marketable fruit yields were highest with October harvest dates in three of the four experiments. Marketable fruit red pigment intensity decreased between the November and December harvest dates at both locations in the second year. When the crop is established by transplanting, paprika harvest should be completed during October in the southwestern United States.
C.A. Sanchez, R.L. Roth, B.R. Gardner, and Harry Ayer
Field studies were conducted to develop water and N response surface models for broccoli and cauliflower (Brassica oleracea L., Botrytis Group) produced in the low desert of the southwestern United States and to estimate profit maximizing combinations of water and N over a range of realistic price situations. Marketable broccoli and cauliflower yields were increased by water and N inputs in all experiments. Generalized response equations indicate maximum broccoli yields with 43 cm of water and N at 267 kg·ha–1 and maximum cauliflower yields with 65 cm of water and N at 338 kg·ha–1. Least-cost combinations of water and N changed with the costs of these inputs for yield levels below the economic maximum. However, profit maximizing N and water rates changed little regardless of input or crop prices investigated.
C.A. Sanchez and N. Obeker
Approximately 30,000 ha of iceberg lettuce (Lactuca sativa L.) are produced in the low desert region of the southwestern United States during the fall–winter–spring period each year. During this period, soil temperatures in lettuce beds range from 10 to 30°C. During the cooler part of the growing season, growers typically use nitrate-N sources because they believe they are generally more available for plant uptake. However, limited experimental evidence exists to support this practice. Three field studies were conducted during the 1994–1995 growing season to evaluate the response of iceberg lettuce to N rate and N source. The N sources urea, ammonium sulfate, ammonium nitrate, and calcium nitrate were applied at rates ranging from 0 to 300 kg N/ha. Although lettuce growth, N accumulation, and marketable yield significantly increased by N rate, there were generally no differences due to N source.
Monte L. Nesbitt, J.B. Storey, S.D. Lyda, and L.J. Grauke
Phymatotrichum Root Rot, caused by Phymatotrichum omnivorum (Shear) Duggar, imposes severe losses upon dicotyledonous horticultural crops in the southwestern United States and northern Mexico. Rootstock resistance could benefit pecan (Carya illinoensis) production in affected growing areas; however, erratic growth habit of this pathogen and site variability prevents effective field screening. We have developed a containerized screening method for horticultural crops, using a commercial soilless growing medium. In sterile cultures, 2.5 × 60 cm glass tubes containing Metro Mix 500 yielded more grams of P. omnivorum sclerotia than cultures grown in Houston Black Clay, a traditional medium for cotton research. Preliminary screening with Okra (Abelmoschus esculentus) in non-sterile Metro-Mix 500 resulted in 75% mortality of inoculated plants in 30-35 days. Preliminary screening with 12-week-old, open-pollinated `Apache' and `Moore' pecan rootstocks has resulted in 25% mortality of inoculated plants in 150 days. Pecan seedlings with visible taproot infection appear to delay mortality by adventitious root formation.