Effect of Nitrogen Fertilization on Yield, Composition, and Quality of Kenaf1

Abstract

AbstractKenaf (Hibiscus cannabinus L.), a potential pulp crop, has not shown a consistent yield response to N, and the influence of N on pulp quality factors is unknown. The response of kenaf to lime and the amounts of various elements removed with the harvested crop are also of interest. A field study was conducted to determine the effect of N on yield, mineral composition and quality of kenaf at two pH levels. Tests were conducted for 2 years, 1970 and 1971; in two soil areas, Edisto (Glossaquic Fragiudalf) and Ona (Typic Haplaguod); and in high and low pH areas established by, prior applications of lime. Nitrogen was applied at three levels and in single and three‐way split applications. Nitrogen increased the yield, height and diameter of kenaf. Nitrogen had the favorable effect of increasing woody fiber length, however lignin content was also increased. Cellulose content was unaffected. Split applications of N usually produced higher yields than the same amount in a single application but were only significant for the fist year on limed Edisto soil. Increasing rates of N decreased the P, K, Ca and B content of harvested kenaf. Lime increased the Mg content an1 reduced the Mn, Al, Sr, and Ba contents. Neither N or lime had any significant effect on ZnZ Cu or Mo content.