Promotion of flowering inEucalyptus nitensby paclobutrazol was enhanced by nitrogen fertilizer

Abstract

Abstract:We examined the effects of nitrogen and phosphorus fertilizer and paclobutrazol on flowering precocity and abundance in Eucalyptus nitens Deane & Maid. Trials to test these effects consisted of a factorial nitrogen by phosphorus experiment replicated on two sites and factorial nitrogen by paclobutrazol experiments conducted separately on reproductively immature and reproductively mature trees. The increase in tree size due to nitrogen fertilization increased the occurrence and abundance of precocious flower buds. However, the increase in tree size alone could not account for the nitrogen effect on flowering, indicating a secondary mechanism of flower induction by nitrogen. The application of both nitrogen fertilizer and paclobutrazol substantially increased the occurrence of precociously flowering trees over that of either treatment applied alone. The efficacy of both paclobutrazol and nitrogen in stimulating the flowering of the reproductively mature trees was affected by soil type, but this effect was overcome through the combination of nitrogen and paclobutrazol. The combination of nitrogen and paclobutrazol also restricted tree growth and combined applications on nitrogen deficient sites will be beneficial in commercial systems for producing eucalypt seed.

Growth and Anatomical Responses in Xanthostemon chrysanthusas Influenced by Paclobutrazol and Potassium Nitrate

“…These results showed that PBZ inhibited the tree growth. Previous research also reported that PBZ resulted in plant height reduction (Ahmad Nazarudin 2012;Gent 2004;Pinto et al 2005;Taiz & Zeiger 2006;Williams et al 2003).…”

The effect of autumn N supply on the architecture of young peach (Prunus persica L.) trees

“…But, whether the previous year's fertilisation increased precocity is still under discussion. No effect was found on burst for vegetative buds (Floistad 2002 on conifers), but flowering was advanced on eucalyptus (Williams et al 2003) and apple (Wojcik and Klamkowski 2005).…”

Genetic variation for early flowering, survival and growth in sugar gum (Eucalyptus cladocalyx F. Muell) in southern Atacama Desert

“…Wiltshire et al (1998), on the other hand, found a moderate genetic control for early flowering but only a weak genetic relationship between this trait and growth within and between populations of Eucalyptus. Williams et al (2003) also found that early flowering could also affect the growth and the development of trees, although in their study early flowering was artificial promoted, rather than a genetically determined. Data presented in this paper indicate that selection for precocity may significantly enhance both growth and survival (Table 3).…”