ASSESSMENT OF BURLEY TOBACCO NITROGEN NEEDS FOLLOWING COVER CROPPING AND MANURE APPLICATION

Abstract Nitrogen (N) fertilizer recommendations for burley tobacco (Nicotiana tabacum) seldom are adjusted to compensate for available N supplied when cover crops and/or animal manures are part of the cropping system. A field study was initiated to assess i) N availability from cover crops and manures to burley tobacco, ii) response of burley tobacco to N fertilizer provided by cover crops or manures, and iii) the usefulness and adaptability of soil testing and/or plant analysis for evaluating the supplemental fertilizer N needs of burley tobacco. The experimental design was a split-plot with fallow, crimson clover (Trifolium incarnatum), hairy vetch (Vicia villosa), rye (Secale cereale), and rye + hairy vetch cover crops and fall-applied and spring-applied manure as main plot treatments and five fertilizer N rates ranging from 0 to 200 kg N ha−1 in 50 kg N ha−1 increments as split-plot treatments. Soil and tobacco petioles were sampled in the 0 kg N ha−1 check plots during the growing season to determin...