Performance of Satsuma Mandarin Protected from Freezing Temperatures by Microsprinkler Irrigation

in HortScience
View More View Less
  • 1 Alabama Agricultural Experiment Station, Gulf Coast Regional Research and Extension Center, 8300 State Highway 104, Fairhope, AL 36532
  • 2 Department of Horticulture, Auburn University, 101 Funchess Hall, Auburn, AL 36849-5408
  • 3 Department of Horticulture, Auburn University, 101 Funchess Hall, Auburn, AL 36849-5408

Several microsprinkler treatments were tested on 5-year-old satsuma mandarin orange (Citrus unshiu Marc.) trees to compare survivability of trunks and scaffold limbs in severe freezes. Three damaging freeze events occurred during winter, with two in 1995–96 and one in 1996–97. Air temperature dropped to –9.4, –5.6, and –6.7 °C, respectively. Almost 90% of the foliage was dead on the control plants after the first freezing event and 98% after the second. A single microsprinkler 1.6 m high in the canopy delivering 90.8 L·h–1 reduced injury; only 54% of the canopy was dead after the first freeze and 71% after the second. There was slightly more shoot-tip dieback on the plants in the microsprinkler treatments than on the control plants after the first two freezes. The amount of limb breakage by ice was minor. The third freeze killed 34% of the canopy in the control plants, but only 26% in the plants in the microsprinkler treatments. Use of microsprinklers increased yield in 1996, but yield for all treatments was very low. Yield for all treatments fully recovered in 1997, averaging 153 kg/tree. Although no death of scaffold limbs or trunks occurred, these results demonstrate that microsprinkler irrigation reduces damage to foliage and increases yield somewhat in severe freezes.

If the inline PDF is not rendering correctly, you can download the PDF file here.

Contributor Notes

to whom reprint requests should be addressed. E-mail: rcebel@acesag.auburn.edu
All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 93 44 2
PDF Downloads 154 71 20