title: Effects of variety and site management on tree water and nitrogen use efficiency as well as biochemical composition and quality of tropical mango (Magifera Indica L.) fruit in northern Australia
Creators: name: Sun, Weiling
Publisher: name: Griffith University
Year: 2020
Subjects: subject: Soil security
subject: Food security
subject: Mango

description: Soil security and freshwater resources are closely linked to food and human security in the 21st century. By 2050, global demand for food will increase by more than 60% from the current situation, which is driven by the growth of global population and global wealth. Since the Industrial Revolution, rapid population growth has depended on growing land development to achieve responsive growth in food production, unprecedented global climate change, and rapid urbanization and industrialization in emerging economies. This is in the context of an unprece dented global challenge of climate change, which is a major threat to global food security. Climate change, especially global warming, is expected to intensify in the next few decades. At the same time, the decline of fresh water supply is becoming a globa l crisis. Therefore, it is becoming increasingly important to adopt water saving strategies in agriculture. In the context of unprecedented climate change, water resource constraints, and increasing threats to soil and water security, Australia is facing t he problem of maintaining and improving agricultural productivity, requiring the integration and transformation of food production systems to address global sustainability challenges. Therefore, there are an urgent need and exciting opportunity to launch t his project to meet the soil and food security challenges facing in the coming decades. Mango (Magifera Indica L.) is known for its excellent exotic flavors. High quality mango fruit is attractive to consumers with its excellent fruit quality and good fre sh keeping quality. Mango fruit is one of the most important commercial fruit crops. It is the second largest tropical crop after bananas in terms of production, acreage and popularity. It is widely planted in tropical and subtropical regions, and its glob al output in 2003 exceeded 25 million tons. Extensive plant breeding has produced hundreds of varieties whose fruits show significant diversity in size, shape, color, taste, seed size and composition. Many of these studies have shown that the compositional changes of mango fruit depend to a large extent on the variety harvested, the climate and the stage of maturity. Current methods for determining the quality of mangoes are mainly based on biochemical analysis, which will cause fruit damage. This study wil l discuss the use of some non destructive techniques to determine the effects of variety and site management on the biochemical composition and quality of mango fruits in northern Australia. Soil (0-10 cm), mango foliar and mango pulp samples were collect ed from a 5 year old, factorial field experiment testing the effects of two mango varieties (Calypso vs Keitt), two planting densities (medium vs high), two training systems (single leader vs conventional) and two sampling canopy (medium vs high), two training systems (single leader vs conventional) and two sampling canopy positions (north vs south)positions (north vs south) on foliar and pulp total carbon (TC, %), total nitrogen concentration (TN, %), on foliar and pulp total carbon (TC, %), total nitrogen concentration (TN, %), and stable carbon (C) and nitrogen (N) isotope compositions (δand stable carbon (C) and nitrogen (N) isotope compositions (δ1313C and δC and δ1515N) as well as the N) as well as the corresponding total C, total N and δcorresponding total C, total N and δ1313C and δC and δ1515N in the surface soil of tropical AustN in the surface soil of tropical Australia. In addition, ralia. In addition, mango fruit yields and sizes were determined. Soil, pulp and foliar total C and N as well as δmango fruit yields and sizes were determined. Soil, pulp and foliar total C and N as well as δ1313C and C and δδ1515N were determined on mass spectrometers at Griffith University. Each of the above treatments N were determined on mass spectrometers at Griffith University. Each of the above treatments was replicated 6 times for foliar and was replicated 6 times for foliar and pulp samples and 3 times for soil samples. In addition, the pulp samples and 3 times for soil samples. In addition, the solidsolid--state state 1313C MAS NMR measurement determined the changes in the chemical composition of C MAS NMR measurement determined the changes in the chemical composition of mango fruits between different varieties, planting densities, cultivation systems, and canopy mango fruits between different varieties, planting densities, cultivation systems, and canopy positions. Fpositions. For the pulp samples in the experiment, each of the above treatments was repeated 6 or the pulp samples in the experiment, each of the above treatments was repeated 6 times.times. In this fiveIn this five--yearyear--old mango orchard, there were significant genetic and environmental old mango orchard, there were significant genetic and environmental influences on tree water and nitrogen use efficiency as well as mango fruit yielinfluences on tree water and nitrogen use efficiency as well as mango fruit yield, which shows d, which shows significant potential for improvement of mango tree WUE and NUE as well as fruit yield and soil significant potential for improvement of mango tree WUE and NUE as well as fruit yield and soil fertility. There were also significant genetic and environmental impacts on the contents of fertility. There were also significant genetic and environmental impacts on the contents of carbohydrates and protein and chemical components in carbohydrates and protein and chemical components in mango pulp. The results of this study would mango pulp. The results of this study would inform future commercial orchard site management and plant breeding practices and therefore inform future commercial orchard site management and plant breeding practices and therefore assist in optimizing commercial fruit production.assist in optimizing commercial fruit production.