Long-term Effects of Nitrogen and Drip Irrigation Water Levels on Almond Yields
Autor: | H. Schulbach, J. Deng, J. P. Edstrom, R. D. Meyer |
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Rok vydání: | 1997 |
Předmět: | |
Zdroj: | HortScience. 32:545A-545 |
ISSN: | 2327-9834 0018-5345 |
DOI: | 10.21273/hortsci.32.3.545a |
Popis: | Five rates of urea-N each at two water levels (0.6 & 1.0 ETc) were applied to three varieties (Butte, Carmel, and NonPareil) of almonds [Prunus dulcis (Mil) D. A. Webb] planted in 1981 on a 3.65 × 5.47-m spacing (550 trees/ha) on Arbuckle gravelly loam (Fine-loamy, mixed, thermic Typic Haploxeralf). Trees were drip-irrigated to basins (three per tree) ≈7 cm deep and 30 cm in diameter, located 76 and 183 cm on either side of the trees in the tree row. N rates ranged from 0–57, 0–198, 0–454, 113–907, 170–1361, 227–1814, 227–1814, 170–1361, 113–907, 113–907, 113–907, 0–907, 0–907 and 0–907 g per tree, respectively, during 1982–1995 and were applied on a monthly basis in four to six increments beginning in April. Almond meat yields were >1500 kg·ha–1 in 1984 and as high as 3800 kg·ha–1 during the 12-year period for the 1.0 ETc water treatment and optimum N rate. Nitrogen response was generally in the 600–1000 kg·ha–1 range, with water treatment response in the 200–500 kg·ha–1 range. The three varieties generally responded to higher N and water rates in the order Butte > Carmel > NonPareil. Leaf analyses (three to six each year) were used to monitor treatment effects and evaluate need for other nutrients. |
Databáze: | OpenAIRE |
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