Technical annual report 2000-01
Dept. of Regional Development, Primary Industry, Fisheries and Resources technical annual report; Department of Regional Development, Primary Industry, Fisheries and Resources technical and annual report; Reports; PublicationNT; Technical bulletin (Northern Territory. Dept. of Primary Industry and Fisheries) ; no. 295
2001-10
Made available via the Publications (Legal Deposit) Act 2004 (NT).
Date:2001-10
English
Agriculture -- Northern Territory -- Periodicals; Fisheries -- Northern Territory -- Periodicals
Dept. of Primary Industry and Fisheries
Darwin
Technical bulletin (Northern Territory. Dept. of Primary Industry and Fisheries) ; no. 295
0158-2763
Check within Publication or with content Publisher.
https://hdl.handle.net/10070/223369
https://hdl.handle.net/10070/687151
Department of Primary Industry and Fisheries 132 loggers are used to record temperature and relative humidity. The management of trees is assessed by taking soil samples to monitor soil nutritional status, leaf samples to monitor leaf nutritional status and irrigation inputs using water meters. In addition the growers are recording when and how much fertiliser they apply and when they carry out other management operations. From this information, the relations between tree performance and climatic and management factors will be assessed. The trial started in Katherine region in July 1998. The sites were visited weekly in 1998 and 1999 seasons, fortnightly in 2000 and monthly in 2001, to take readings and samples. Results and Discussion: Monitoring in this project will cease with the harvest in November 2001. All the data from the three years of this project is being recorded in databases for analyses. It is anticipated to use this information in conjunction with data collected by the CSIRO Horticulture staff in Darwin to develop a model on mango growth. PROJECT: Foliar Nitrogen Nutrition Trials in Mango Project Officers: J. Bright, S. McAlister and R. Renfree Location: KRS Objective: To investigate the role of nutrition in the productivity of trees. To standardise nutrition management practices in the Darwin and Katherine regions. The nitrogen nutrition of mango remains an area of much debate and confusion. Over the last decade in the NT there have been major swings in the quantity of nitrogen recommended for commercial orchards. Current rates range from zero to 300 g N per tree per year. Foliar application of nitrogen has received limited attention. Method: The experiment was established on four-year old trees at Katherine Research Station, in January 1996, with three different rates of nitrogen and a control (80, 40, 20 and 0 g N/tree). The rates of nitrogen applied for each treatment were increased in 1998, as they appeared to show no detrimental /positive effects on tree growth and production. Application rates in the last few years of the trial were 140, 90, 60 and 0 g/tree/year applied at four different phenological stages (post-harvest flush, pre-flowering, fruit at golf-ball size, and split between all three of these stages). These treatments were arranged in a factorial design with five replicates and individual tree plots. Results: The 2000 harvest was the final for this trial. An analysis of results for each year, from 1996 to 2000 and over all years, using Bonferronis inequalities shows no significant differences between different foliar nitrogen treatments with respect to: control versus nitrogen treatments for weight and number of fruit and average weight of fruit (in each year) and yield quantity and quality (LSD=4.0) (over all years); timing of nitrogen for average weight of fruit (in each year) and yield quantity and quality (LSD=4.0) (over all years); nitrogen rates for weight and number of fruit (in each year) and yield quantity and quality (LSD=4.0) (over all years); interaction between timing and nitrogen rates for average weight of fruit (in each year) and yield quantity and quality (LSD=4.0) (over all years).