Effect of nitrogen source on growith of Eucalypts in sand culture

Abstract

Twelve species of Eucalyptus were grown in sand culture to determine their response to nitrate and ammonium nitrogen, and to different proportions of the two ions. Response was measured in terms of plant height, yields of plant parts (stems, branches, leaves, and roots), and number of branches. The results indicate a wide variation in the response of different species to form of nitrogen. A classification of species in terms of their overall response bears no relation to the accepted taxonomic classification. On the basis of the results for the 12 species, it appears that plants of similar ecological habitat tend to have similar responses. Thus, typical woodland species (E. melliodora, E. blakelyi, and E. albens) behave quite differently from typical forest species (E. rossii and E. sideroxylon). Nevertheless, there are differences within such general groupings; e.g. forest species such as E. Agglomerata and E. macrorhyncha form a distinct group, apparently unrelated to the other forest species tested. The response of E. polyanthemos, which occurs in both dry sclerophyll forests and woodlands, is similar to that of the typical forest species. When Eucalyptus species are to be grown in sand culture for nutrition or other trials, a preliminary test is necessary to determine the preferred form of nitrogen for each species. Otherwise the effects of the factor being tested may be so masked as to render the test valueless.

NITROGEN SOURCES AND DOSES ON GROWTH AND QUALITY OF SEEDLINGS OF Cassia grandis AND Peltophorum dubium 1

“…Santin et al (2014) evaluated the productivity of Ilex paraguariensis as a function of different N sources and observed that its preference for nitrogen source is dependent on the place of origin of the crop. A similar result was observed (Moore and Keraitis, 1971) who assessed the growth of 12 Eucalyptus species in relation to the N-NO 3-and N-NH 4+ and found that plants of ecological habitat similar tend to have similar responses in relation to the preferred source absorbed.…”

Eucalyptus recruitment in degraded woodlands: no benefit from elevated soil fertility

“…Growth responses are primarily to N (Moore and Keraitis 1971;Cromer and Jarvis 1990;Kirschbaum et al 1992), P (Kirschbaum et al 1992), or both in interaction (Halsall et al 1983;Fabião et al 1995); the main effects being increased shoot to root ratio, specific leaf area (SLA) and photosynthetic rate (Stoneman 1994). Improved soil nutrition was also shown to reduce seedling mortality of Eucalyptus incrassata seedlings by about 30% (Stoneman et al 1993).…”

Diagnosis of nitrogen deficiency and toxicity of Eucalyptus globulus seedlings by foliar analysis

“…comm. ), or to pH effects (Moore and Keraitis, 1971) . The pH of the sand did not change in the nitrate treatment so that pH alone could not explain the depression in yield .…”

“…Little is known about the N requirements of E. globulus during this early growth stage . Furthermore, some forest eucalypt species are known to have a preference for ammonium-N rather than nitrate-N (Moore and Keraitis, 1971), although this can vary with the extent of mycorrhizal colonisation of seedling roots (Dell et al ., 1991) . The capacity of E. globulus to utilise high levels of nitrate-N is unknown, but this will be a significant factor determining N uptake where seedlings are planted on agricultural land .…”