Improvement in Leaf Quality of Shade Grown Tobacco with Supplemental Applications of Soluble N under Plasticulture(Abstract)

摘要

In 2006,shade grown tobacco was planted in a sandy soil in raised beds with drip irrigationunder plastic mulch.Prior to bed formation,plots were treated with a fertilizer whose N portionconsisted primarily of organic sources including cottonseed,soybean and linseed meals at rates of 150 or205 lb N per acre.Supplement soluble N was applied as ammoniacal and nitrate sources (15-15-15)through the drip irrigation to subplots according to the following rates and schedules:A.none;B.6 lb Nat 72 days (after planting) and 10 lb N at 78 days (total 16 lb N);C.5 lb N at 68 days,10 lb N at 78 daysand 10 lb N at 92 days (total 25 lb N);D.5 lb N at 64 days,5 lb N at 68 days,6 lb N at 72 days,10 lb Nat 78 days and 20 lb N at 92 days (total 46 lb N).There were 3 replicates of each treatment in a 2X4X3factorial design.Leaf samples for each treatment were taken at 71,88 and 102 days after planting (3rd,5th and 7th commercial harvest dates) and bulked among each treatment for quality evaluation bycommercial appraisers (% cigar wrappers) and yield.(number of leaves per pound).Quality and yield oftobacco fertilized with 205 lb N preplant was higher throughout the experiment than 150 lb N.Allsupplement soluble N treatments (B,C and D) had better leaf quality than the untreated plots (A).Supplement treatments B (16 lb N/A) and C (25 lb N/A) had the best leaf quality at each harvest.Theseresults suggest that low rates of supplement soluble N can be applied through drip irrigation to improveleaf quality of shade grown tobacco under plasticulture.