This project combined two projects previously supported by the CRDC and one by the Cotton CRC that contributed to the development of decision tools for the cotton industry. This project alone was the principle project that supported the cotton industry&#39s investment in decision support development.502

Australian cotton is purchased for a premium on the basis of quality and consistency. However, coarse (high micronaire) fibre, high nep counts and excessive short fibre are industry concerns. Quality is affected by many interacting factors e.g. variety, seasonal conditions and crop and harvest management. Appropriate varieties, management for each region's climate, and processing to minimise damage to fibre are opportunities to improve fibre quality. Through a significant combined research effort this project aimed to optimise cotton fibre quality of Australian cotton by: direct influences of on-farm agronomic management and climate on fibre development; and post-harvest research that investigated the degree of these influences on textile performance in the mill.

Carried out as a summer scholarship between December 2012 and March 2013, the researcher sought to outline the potential contribution of corn in rotation with cotton, in comparison to historical cotton and wheat rotations after minimum or maximum tillage. It tested the hypothesis that there is no difference in cotton root growth for cotton grown in a cotton monoculture, and after wheat and corn. Understanding cotton root growth and turnover will enhance the capability for primary industries to adopt more resilient and adaptive farming strategies and systems, and also encourage adaptive strategies to change initiatives and resource development. A better understanding of cotton root growth characteristics under monoculture and different rotations will provide growers with better crop water and nutrient management strategies.The field experiment was conducted in Narrabri NSW, consisting of six treatments in a split plot design with four replicates. The experiment used minirhizotron, core break, root washing and plant mapping methods to measure cotton root growth and turnover during the 2012/2013 growing season. Cotton vegetative growth and potential carbon input by cotton roots was improved by including corn in rotation (cotton-corn-cotton) relative to historical cotton rotations.

It was demonstrated that varying irrigation deficits, if linked to measures of plant stress, will improve cotton yield and WUE. These benefits if adopted will impact on the 75% of Australia's irrigated cotton that is grown in a sub-humid climate with significant but variable in-crop rainfall and evaporative demand. When conditions were hot and dry during flowering, as in the 2006/7 season, frequent irrigation of Bollgard II cotton (40mm deficit) increased yield by 17% and WUE by 8% compared to the commonly used deficit (70-80mm) in the lower Namoi that season. In contrast, in 2007/8, where during flowering in-crop rainfall was greater and evaporative demand lower, stretching irrigation during flowering (54 to 78mm deficits) maximised yield, WUE and captured more in-crop rainfall than irrigating at a 40mm deficit. However, irrigation application efficiency tradeoffs are farm specific and need to be measured before adopting small deficits.Improved scheduling of Bollgard II in water limited situations has been largely achieved with the contribution of the research conducted in this project. The need to avoid water stress late in flowering in Bollgard II was confirmed as yield losses per day of stress were double the conventional variety at the same growth stage. This message has been widely extended over the past three years.The question of which has the higher WUE, conventional or Bollgard II varieties, has been answered by showing that it depends on the impact that Helicoverpa damage has on crop morphology. In a situations where insect damage was moderate Bollgard II used less water than the conventional variety because the conventional variety grew for longer to compensate for the damage. Where insect damage is minimal there is no difference because the plants are morphologically identical. However the situation where early tipping of the main-stem was the only insect damage to the conventional variety, it had the highest yield and WUE due to the improved canopy structureThe irrigation water requirement of cotton in pressurised systems (e.g. tape) was sensitive to climatic conditions and could be reduced provided the crop factor is varied in response to plant growth and climate. Cotton grew differently in this system compared to furrow irrigation.OZCOT model enhancement is need if it is to effectively simulate climatic risk in new production regions or changed cropping practices or the simulation of water balances or climate change scenarios.This project produced data to show: 1) replication is essential for paddock size water balance trials and experiments; 2) a review of plant monitoring methods for early irrigation scheduling is required; 3) new research methodologies developed here will provide indirect benefits to the cotton industry.

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The project, Regeneration of floodplain vegetation in response to large-scale flooding in the Condamine-Balonne and Border Rivers, was a collaboration between the Cotton CRC, QLD DERM, NSW Office of Water and the Australian Rivers Institute of Griffith University. The aims of the project were to i) describe spatial and temporal patterns in the regeneration of major riparian tree and shrub species in the Condamine-Balonne and Border Rivers following the major floods of early 2011 and ii) identify key factors, particularly hydrological, influencing these patterns.The project comprised two major components: i) a literature review and associated development of conceptual models for key riparian tree and shrub species of Australian arid and semi-arid catchments and ii) a field study program. The field study program involved surveying up to twenty-five 50m long transects across nine sites along the Weir, MacIntyre and Balonne rivers on three occasions: September and November 2011 and March 2012. Prior to the first survey all sites received significant overbank flows preceded by an extended period of drought (c. 10 yrs). Further flooding also occurred during the study period prohibiting repeated surveys at several sites. During each survey, all woody seedlings (< 1 m) present in transects were recorded and measured. Relevant environmental characteristics were also measured (e.g. soil characteristics, canopy cover, elevation etc.) and the composition of the canopy and presence of seeds recorded. Additionally, a further 70 seedlings across four sites, including Eucalyptus coolabah (coolibah), Acacia stenophylla (river cooba) and Atalaya hemiglauca (whitewood) were tagged and measured to monitor survival and growth during the study period.Seedling establishment was found to be sparse and spatially patchy. Over half of seedlings recorded during each trip were Acacia stenophylla seedlings and these were present at all sites. Muehlenbeckia florulenta (lignum) seedlings were also relatively common and widely distributed. Eucalyptus coolabah seedlings were comparatively rare but were present at six of the nine sites. Atalaya hemiglauca (whitewood) seedlings were also encountered relatively frequently. Only two Eucalyptus camaldulensis (river red gum) seedlings were observed in the entire field study. The range of seedling sizes present at each time suggest that the Acacia stenophylla seedlings observed represented single germination events on each occasion with the tagged seedling study also suggesting limited survival of small seedlings between September and March. Eucalyptus coolabah seedling sizes were also indicative of a single, but considerably earlier, establishment event. In contrast, Muehlenbeckia florulenta appears to be recruiting continuously in these habitats. Larger tagged Acacia stenophylla seedlings exhibited rapid growth over the survey period while Atalaya hemiglauca displayed slower growth and Eucalyptus coolabah seedlings showed a mixed growth response.Significant variation in the composition and density of seedling assemblages was detected between the major river catchments, driven by the abundance of Acacia stenophylla seedlings, with strong variation at the site-scale also apparent. For the September 2011 observations, total seedling density was negatively related to the time since inundation and the duration of the last flood event positively related to Acacia stenophylla seedling density and negatively related to Eucalyptus coolabah density.The results of this project indicate that large floods do not necessarily trigger major recruitment events amongst key riparian tree and shrub species in this region. Recruitment of key species (e.g. Eucalyptus camaldulensis and E. coolabah) does not appear to be limited by seed availability as seeds were observed in the canopy and on the soil surface at all sites.Consequently, germination and seedling establishment in these species are likely to require floods with particular attributes (e.g. duration, timing etc.) possibly in combination with a suite of other conditions (e.g. rainfall, temperature). Understanding vegetation regeneration in these significant habitats to better inform water resources management will depend on the establishment of a well-designed long-tem monitoring program that captures recruitment patterns over a large and diverse array of sites.

Cold shock at temperatures below 11C was previously believed to delay cotton development. This paper tested whether exposure to 10C for 10 and 20 nights affected tissue viability. Experiments were conducted using plants grown in the glasshouse at the 14-node stage and plants grown outdoors at the 7-node stage. Simple tissue viability tests using tetrazolium (TTC) and relative electrical conductivity (REC) were conducted following treatments. Leaf photosynthesis and chlorophyll fluorescence were also measured to determine whether there were changes in photosynthetic function. Plants treated with cold shock at 10 'C for 10 and 20 nights did not show any significant impact on tissue viability or cell membrane integrity in the TTC and REC tests, respectively. Photosynthesis and chlorophyll fluorescence levels fell slightly in the 20 night treatment compared to the control, but recovered quickly outdoors at the end of the 20 nights. There was no evidence in the data that exposure to 10C for 10 and 20 nights will reduce cotton tissue viability or plant growth.

The salts of many essential plant nutrients are soluble in water and may be applied to plant leaves directly as a foliar fertiliser. This practice has become widespread in the American and Australian cotton industries over the past 20 years as a means of correcting crop nutrient deficiencies and supplying nutrients to plants during peak demands when root uptake may not be adequate to meet plant demands. The efficacy of these foliar fertilisers, and the yield and quality benefits that may be obtained is debatable. Variable plant responses to foliar

fertilisers have been recorded, ranging from yield increases of 30% to a reduction in photosynthesis and leaf functioning. Knowledge about the precise mechanisms of penetration of foliar applied chemicals is limited, and the factors contributing to the effective uptake of foliar applied nutrients are insufficiently understood to explain the highly variable yield responses recorded. This review will examine the factors affecting the penetration and uptake of foliar applied nutrients, and discuss the potential of this practice to supply nutrients to

developing crops and supplement soil fertilisation in a commercial system.

Cottonspec is a yarn quality prediction software developed by CSIRO with support from the CCC CRC, CRDC and Chinese partner mills. Validation trials conducted as part of this project showed Cottonspec was a useful mill management tool, giving spinners immediate feedback on the fibre they use in terms of yarn quality. The software program gives excellent predictions of yarn tenacity and evenness from (five) HVI properties.Cottonspec will be launched in China later this year at a technical seminar to be held jointly by CSIRO, ACSA and the China Cotton Textile Association (CCTA).Cottonspec has the capacity to improve the classification of Australian cotton by linking cotton fibre quality with yarn quality with theoretical modelling. The prediction algorithms favour fine, long, strong cotton, i.e. play on Australian cotton fibre characteristics. The package can be used by spinners to select the most suitable cottons that best meet the spinner's needs, or as a quality control tool to benchmark performance against &quote;best commercial practice&quote;. Cottonspec can also be used as a trading tool for merchants to promote the value of a particular growth, or used by cotton researchers and grower collectives to assess and promote new cotton varieties.Cottonspec could prove to be an invaluable tool to promote Australian Long Staple (ALS) cotton to mills for production of high quality yarns. Cottonspec has excellent potential to help create demand pull from high-end mills for ALS cotton. The commercialisation of Cottonspec through an extension project will create stronger partnership with quality mills to enable feedbacks on future fibre quality demands and yarn and fabric trends; and to create demand for ALS cotton.The impacts of Cottonspec on mill performance are demonstrated by the example of the Chongqing Sanxia No. 1 Mill, a key partner mill in the project. Established in 2005 this mill is one of the most modern mills in China. Through collaboration with the Cottonspec project the quality of yarn produced by this mill has lifted dramatically. Now the mill is among the top five mills in China in terms of quality. All of the yarn this mill produces is exported to Europe and Japan. Moreover, before the project this mill had never used Australian cotton. In 2010-2011 this mill used 3350 tons of Australian cotton, making up about 20% of its lay-downs and its management has made plans to increase this proportion in the next few years.The successful commercialisation through the extension project 'Commercial Ready Cottonspec' will enhance the cotton industry&#39s current drive towards the production of high quality fibre that is differentiated by its inherent quality and the information around its quality. The combination of industry understanding and demand pull from stragegic partner mills in China for high quality Australian cotton will help fulfil the industry&#39s ambitions to develop a high quality product. 28 of 28

This project initially set out to advance the industries capacity to manage water quality through the development of constructed wetlands. Background knowledge included positive results regarding increases in biodiversity and improvement in water quality from pilot-scale wetlands. However, it was identified that the predominant concern of the industry was water availability because of dryer than average climates. Additionally, it was established that irrigators were more interested in whether or not the quality of their tailwater actually required improvement, but had no straightforward methods to attain this insight.As a result this project developed a simple water quality test kit to analyse irrigation water. In a pilot study, 20 water quality test kits and protocols were distributed within the industry, including some properties growing crops other than cotton. Key water quality parameters including, turbidity, temperature, EC, pH, carbonate hardness, total hardness and nitrite, nitrate, ammonium, phosphate and chloride ion concentrations were recorded during irrigations.Although the feedback from participants was positive, the amount of data returned was not sufficient to enable a full analysis of water quality. We expect that reduced on-farm staffing levels, as a consequence of very limited water availability, were too restrictive to allow sufficient resources to be made available for the trial.Analysis of preliminary results indicated that at least 15 to 30 % of nitrogen was lost to the tailwater systems as nitrate. This indicates that significant economic gain can be made through improving the efficiency of nutrient use. The main benefit of the water quality kits was that they provided a quantitative approach for environmental management. Site-specific water quality measurements could be collected that were directly related to local practice. Any change in practice, that affects nutrient use efficiency, could be assessed, thereby informing and quantifying environmental management systems such as BMF. Economic value of improvement in practice can be readily determined from tailwater quality data thereby providing further impetus for improvements.The water quality tests provide the cotton and irrigation industry with a simple tool to seek, measure and record economic and environmental improvement.