• The Citrus Peel Miner, Marmara salictella, in Arizona Grapefruit in 1994

      Gibson, Roberta; Bacon, Dean; Langston, Dave; Kerns, David; Gibson, Richard; Wright, Glenn (College of Agriculture, University of Arizona (Tucson, AZ), 1997-11)
      The life history of the citrus peel miner was investigated. The peel miner larvae were found in low levels in grapefruit throughout the summer. In September the infestation level rose to 10%. Peel miners were also found in oleanders, mesquites, grapes and tree cottons. Peel miners were found to infest at higher levels in the skirt of the tree (less than 32. A parasitic wasp of the larval stage was discovered
    • Effect of Organic Amendments on Lemon Leaf Tissue, Soil Analysis and Yield

      Zerkoune, Mohammed; Wright, Glenn; Kerns, David; Wright, Glenn; University of Arizona Cooperative Extension (College of Agriculture, University of Arizona (Tucson, AZ), 2003)
      An experiment was initiated in 2000 to study the feasibility of growing organic lemons in the southwest desert of Arizona. An eight-acre field was selected on Superstition sandy soil at the Mesa Agricultural Research Center to conduct this investigation. Lemon trees were planted at 25 x 25 feet spacing in 1998. The initial soil test in top 6 inches was 5 ppm nitrate-nitrogen and 4.9 ppm NaHCO3-P. Soil pH was 8.7 in the top 6 inches. Four treatments were applied in randomized complete block design repeated four times. The treatments were beef cattle feedlot manure and perfecta, clover and guano from 2000 to 2002, cowpea and guano in 2003, and guano and perfecta, and standard practice treatment. Soil samples were collected from 0-6 and 6-12 inches the first week of March 2003 and analyzed for available nutrients. Results showed a difference for most nutrients in 0 to 6 and 6 to 12 inches between treatments. Nitrate- nitrogen increased significantly from 3.25 ppm in standard treatment to 19.10 ppm in the manure treatment. Similarly, soil organic matter increased from 0.1% in standard treatment to 0.2% in the manure perfecta treatment. Phosphorus level increased significantly from 7 ppm in guano perfecta to 56.5 ppm in manure perfecta treatment. Leaf tissue analysis indicated that nitrate level was influenced by treatment. Both commercial standard and organic treatments were equally effective in controlling citrus thrips, but repeated applications were required. Mite population has been detected at low level with no significant differences observed among treatments.
    • Effect of Organic Amendments on Lemon Leaf Tissue, Soil Analysis and Yield

      Zerkoune, Mohammed; Wright, Glenn; Kerns, David; Wright, Glenn; Gibson, Rick (College of Agriculture, University of Arizona (Tucson, AZ), 2002-11)
      An experiment was initiated in 2000 to study the feasibility of growing organic lemon in the southwest desert of Arizona. An eight-acre field was selected on Superstition sandy soil at the Mesa Agricultural Research Center to conduct this investigation. Lemon trees were planted at 25 feet spacing in 1998. The initial soil test in top 6 inches was 5 ppm nitrate-nitrogen and 4.9 ppm NaHCO3-P. Soil pH was 8.7 in the top 6 inches. Four treatments were applied in randomized complete block design repeated four times. The treatments were beef cattle feedlot manure and perfecta, clover and guano, guano and perfecta, and standard practice treatment. Soil samples were collected from 0-6 and 6-12 inches the first week of March 2001 and analyzed for NO₃-N NH₄-N, total nitrogen, organic matter and available P. Preliminary results showed no difference in NO₃-N, NH₄-N in 0 to 6 and 6 to 12 inches between treatments. Total nitrogen increased significantly from 0.0262% in standard treatment to 0.0375% in the manure treatment. Similarly, soil organic matter increased from 0.297% in standard treatment to 0.4337% in the manure perfecta treatment. Phosphorus level increased significantly from 6.962 ppm in guano perfecta to 11.187 PPM in manure perfecta treatment. Leaf tissue analysis indicated that nitrate level was influenced by treatment. Yields of Guano treatments were significantly greater than yields of the other treatments. Both commercial standard and organic treatments were equally effective in controlling citrus thrips, but repeated applications were required. Mite population has been detected at low level with no significant differences observed among treatments.