This project evaluated options for selective control of aphids, studied the field epidemiology of cotton bunchy top disease and determined the suitability of relay crops for aphid pest management. Key conclusions were;

1) Acetamiprid plus pulse provided good control of aphids but flared mites, presumably because it reduced beneficial numbers. This will also be a risk if this product or other neonicotinoids are used against mirids.

2) None of the ‘soft’ soap or oil options alone provides adequate control of heavy aphid populations. Canopy oil may be effective if applied to lower density aphid populations (e.g. less than 10-15 aphids per leaf) in a regular program.

3) The biopesticides evaluated are unlikely to provide the high level of control provided by acetamiprid plus pulse. However, efficacy should improve as more field adapted strains are selected. Used early, these products may be effective at preventing aphid populations from increasing without flaring mites and with reduced resistance risk.

4) CBT appears to be relatively common in aphid populations. CBT affected plants were often observed in the centre of aphid hotspots – often only one or two infected plants are found. In 2005-06 we found CBT affected plants in aphid hotspots in 6 of 8 sites.

5) The latent period of CBT in cotton plants can be relatively short (about 10 days) but is likely to be influenced by aphid numbers (lower densities could have a longer latent period). This is complex and needs further experimentation to sort out.

6) Yellow dwarf forms of cotton aphid transmit CBT poorly compared to ‘normal’ sized aphids.

7) The rate of spread of aphid populations while they are in the apterous form (non-winged) is relatively modest e.g. it took about 40-50 days to travel 8m, both across and along rows. Once populations reach densities that produce alates (winged forms) the spread of aphids could be much faster.

8) Spread of CBT was much faster and higher when the infestations in the field were initiated with a CBT affected plant carrying a high aphid population, compared with those initiated by infesting a field plant with CBT infected aphids. This is likely due to movement of CBT infected aphids off the CBT affected plant compared with movement of clean aphids off the aphid infested plant due to the latent period.

9) In terms of risk of CBT outbreaks – generally low densities of aphids colonising plants means transmission efficiency is low and the latent period likely to be longer, which may severely limit the level of infection in field. Exceptions would be in years were season conditions generated high numbers of aphids and of alternative hosts with CBT – which could then colonise cotton crops at higher densities or situations where stubb cotton was abundant in a field and acted as a source of CBT carrying aphids.

10) The effect of CBT on yield is greater the earlier that plants are infected.

11) Lucerne and sorghum are good relay crops for aphid management as they host aphids that don not attack cotton on which beneficials and parasites could build up and move into cotton.

These outcomes significantly advance our understanding of aphid and CBT epidemiology and will be valuable to industry in developing management strategies.

Regular disease surveys have highlighted the changing status of cotton diseases over time and

provided valuable insights into the factors affecting their distribution and severity.

• The disease surveys provided overwhelming evidence that seedling mortality is not related to the

incidence or severity of black root rot but increases with increasing latitude

• The observed incidence of black root rot has decreased in the past three seasons, most likely as a result

of climatic conditions and drought-enforced fallows but has increased rapidly in the Lachlan and

Murrumbidgee Valleys.

• The rate of reporting of new cases of Fusarium wilt, now totalling 81 farms in NSW, has declined in

recent years, potentially due to farm hygiene, greater deployment of less-susceptible varieties and drier

conditions in spring.

• Fusarium wilt has been observed on 41% of the set of farms surveyed annually in NSW and is

spreading at a steady rate of increase among those farms

• The incidence of Verticillium wilt decreased recently in the Namoi Valley, probably due to greater use

of resistant varieties, although the disease is still observed in 45 to 60 % of fields surveyed annually

across NSW

• An apparent decline in boll rots over recent years probably reflects both the drought and the expansion

of the surveys into southern NSW, where summer rainfall is low.

Experiments were conducted to develop and/or evaluate control strategies for control of

seedling disease, black root rot and Fusarium wilt:

• High seed vigour index, while decreasing seedling mortality, was not related to seedling growth;

seedling mortality was not related to seed mass

• The fungicide DynastyTM consistently performed as well as, and sometimes better than, the standard

fungicides

• Seed treatment with fertilisers and other non-fungicidal products, were not effective in controlling

seedling disease, nor was Bion® in most cases except in crops with Fusarium wilt, suggesting that

Bion® may activate resistance against F. oxysporum f.sp. vasinfectum as a seedling pathogen.

• Seed treatment with Bion® activated resistance against Fusarium wilt and black root rot of cotton,

although its efficacy was variable

• In-furrow application of the fungicide azoxystrobin was very effective in controlling seedling disease in

some seasons at some locations.

• Delayed sowing decreased the period of exposure of cotton to conditions that favour black root rot and

seedling disease, even when cool and wet conditions coincided with the late sowing.

• Pre-plant and at-planting herbicides had no effect on the severity of black root rot or growth of seedling

cotton

• In comparison to continuous cotton, nine years of bare fallow did not eliminate arbuscular mycorrhizal

fungi (AMF) in the soil, although re-colonisation by AMF probably occurred, as the black root rot

pathogen, T. basicola, also colonised the fallowed plots in the absence of plant hosts.

• During bare fallows of up to four years at Bourke, AMF survived in sufficient numbers for normal

development of mycorrhizas in cotton

• AMF were not affected by transgenic cotton varieties

• Seed treatment with a plant flavonoid reputed to increase mycorrhizal development in the field was

phytotoxic at the recommended rate and no conclusion about mycorrhizal effects could be drawn.

• Evaluation of a commercial inoculum, putatively containing mycorrhizal fungi, showed that no

mycorrhizal fungi were present in the product.

Results of these experiments and observational studies have been incorporated in strategies

for integrated disease management and disseminated to the cotton industry by way of

publications, media releases, field days and meetings with growers and consultants.

Fusarium wilt of cotton is caused by the soil-borne fungus Fusarium oxysporum f. sp. vasinfectum (Fov). In Australia, 2 Fov strains are currently responsible for the disease, each belonging to a distinct vegetative compatibility group (VCG). Previous work showed that the 2 Australian Fov strains are genetically related to lineage A of native Fusarium oxysporum, suggesting their local origins.

This project aims to: 1) assess the risk of novel Fov pathotypes emerging from local Fusarium oxysporum population in cotton fields; 2) investigate the evolutionary potential for weakly pathogenic lineage A isolates of native Fusarium oxysporum to become more virulent; and 3) determine the competitive ability of different strains or genotypes of Fov.

Our work showed that Fusarium oxysporum present in the soil of cotton fields consists of 3 major lineages, A, B, and E. The presence of lineage A highlights the likelihood that new strains of Fov may emerge in the future. In addition, the difference in lineage composition between uncultivated soils and cotton fields is noticed, with the dominant form of Fusarium. oxysporum being lineage E in cotton fields but lineage B in uncultivated soils. The evolution of virulence in Fov was studied by carrying out the inoculation – re-isolation – re-inoculation infection cycles successively on a susceptible cotton cultivar. A mildly pathogenic isolate of lineage A became more virulent, causing more severe disease symptoms after 10 infection cycles, and importantly, correlated genetic changes were detected in its offspring isolates. This suggests that weakly pathogenic Fusarium oxysporum isolates of lineage A can become virulent Fov and continuous exposure to susceptible host plants plays an important role in this process.

Based on 350 isolates collected from 6 cotton growing regions in 2002 and 2004, 28 genotypes of Fov were identified, with 21 in VCG 11 and 7 in VCG 12. VCG 11 can be further divided into 2 subgroups and subgroup I-B may represent a new strain of Fov as all members of this subgroup are incompatible with either known Australian VCG. The occurrence of new Fov strains in cotton fields was also detected in other regions like Mungindi. VCG 11 is wides-spread, while VCG 12 is restricted to the Boggabilla area. No genetic structure was found among Fov populations at broad geographic scales, but interestingly some structure was found in the Boggabilla area, with the population in two fields being different from the others. In addition, variation in virulence was observed among different genotypes of Fov.

Field surveys showed that Fov populations may change over time because in one Boggabilla field the dominant Fov genotype was 11-A in 2002 but 11-B in 2004 and, furthermore, genotype 11-A was undetectable in 2006. This change is probably driven by the increasing level of resistance in newly released cotton cultivars planted in the field as our glasshouse trials showed that genotype 11-B is more aggressive than genotype 11-A on the tolerant cultivar, suggesting competitions between strains or genotypes of Fov.

Fusarium oxysporum occurs at comparable levels in the soil of cotton fields (Fov infested or free) in the Darling Downs, Boggabilla, and Moree, however, a clear declining tendency was observed in the frequency of Fov in Fusarium. oxysporum population from the Darling Downs soil to Moree soil. Future studies will focus on soil impacts on Fov since, as a soil-borne fungus, both aggressiveness and saprophytic ability are inevitably influenced by soil biotic and abiotic factors. Insights into how life history traits of Fov and soil factors interact to determine selection for virulence and persistence of the pathogen would aid developing effective disease management strategies.

This project has advanced the use of soil and tissue testing such that growers and advisors are now better able to optimise fertiliser use and have greater confidence in their management practices to provide sound nutrition for cotton crops. Adhering to these best management practices will improve the use-efficiency of fertilisers and reduce the potential for damage to the environment. The large quantities of macro-nutrients removed in seed cotton should be replaced to avoid depleting soil fertility.

Legume cropping can dramatically reduce the requirement for N fertilisers and substantially enhance soil quality. Legumes afford improved soil microbial biomass and reduced soil strength which enables better root growth and facilitates cultivation and tillage. Also, crops are better nourished due to improved availability of nutrients. Economic analyses have demonstrated higher gross margins from legume-based systems due to elevated cotton yields and the reduced requirement for N fertiliser.

By avoiding the overuse of N fertiliser, we can reduce greenhouse gas emissions via nitrous oxide. Further, atmospheric carbon dioxide can be sequestered and soil organic matter increased where tillage is minimised and permanent bed systems installed. Greater research effort is now being placed on the efficiency of N fertiliser use, and the regional extension officers are assisting this. This research offers the industry an opportunity to reduce N fertiliser use and greenhouse gas emissions, without reducing yield.

The results of this research are being extended to the cotton industry but have not been widely adopted by the industry. Further extension activity is planned and training for the extension team and industry on cotton nutrition and soil health issues.

In 2002/03 these chemicals were tested for Helicoverpa species control: Abrade® 50% a.i. (Grow Choice Pty. Ltd), Azamax® 1% a.i. (OCP Pty. Ltd.), BASF320 200g a.i. (BASF), Gemstar® (Bayer Cropscience), Prodigy® 240g/L a.i. (Dow Agrosciences), Rimon® 100g/L a.i. (Nurfarm), S1812 50% a.i. (Sumitomo) and Steward® 200 g/L (Dupont). In 2003/04 the same set of insecticides was used with only one change where Gemstar® was dropped and Intrepid® was included. During 2004/05 season Abrade®, Azamax®, BASF320 and Steward® SC were still included plus new formulation such as DPXKN128 EC, Endosulfan®SC and NNI-0001SC.

Helicoverpa Control: Bt toxin gave the best protection against Helicoverpa damage. Both Steward and S1812 significantly reduced large Helicoverpa. During the last season all tested chemicals except Abrade significantly reduced Helicoverpa numbers. Steward controlled both egg and larval stages while all other chemicals controlled only larvae. NNI 0001, Endosulfan SC and DPXKN128 were very effective on very small and small larvae while NNI 0001 and both the SC and EC formulations of endosulfan were most effective against medium and large larvae. The most efficaceous chemical options for Helicoverpa control were Steward, S1812, NNI 0001 followed by moderately efficacious chemicals such as Endosulfan EC, BASF320 Gemstar, DPXKN128 and Azamax while lower efficacy was seen in Rimon and Abrade.

New chemistry insecticides tested against Aphis spp. control were the same for 2002/03, 2003/04 and 2004/05. It includes, Acetamiprid – Intruder® 225g/L a.i. (Dupont), Carbosulfan – ‘new Marshal’ 250 g/L a.i. (Crop Care), Clothianidine – TI-435 16% a.i. (Sumitomo), Imidacloprid – Confidor® 200g/L a.i. (Bayer Cropscience), Pirimicarb – Pirimor® 500g/L a.i. (Syngenta), Pymetrozine – Chess® 500g/L a.i. (Syngenta), Pyriproxifen – Sumilav® 20g/L a.i. (Sumitomo) and Thiamethoxam – Actara® 250g/L a.i. (Syngenta).

Aphid Control: Best control options for aphids were thiamethoxam, carbosulfan (foliar formulation), acetamiprid and pymetrozine which were indiscriminate and also reduced beneficials. Imidacloprid and clothianidine both showed medium capacity to control aphids and beneficials alike while Pyriproxifen and pirimicarb had the least impact on both aphids and beneficials. There is a known resistance to pirimicarb in most aphid strains but the ineffectiveness of pyriproxifen relates to its mode of action, which does not appear to affect aphids. Acetamiprid, a neonicotinoid insecticide was one of the best performing insecticides in this season’s trial.

Effects on beneficial insects and non-targets: Abrade promoted some Hemiptera pests and reduced some beneficial Coleoptera. Three chemicals consistently stood out for mirid control: Steward, Rimon and BASF 320. Azamax and Endosulfan SC also significantly reduced this pest. Steward was the overall choice for the reduction of sucking pests including jassids and apple dimpling bugs; however, it was not very effective against thrips and was hard on some beneficials. Both BASF 320 and Intrepid negatively affected wasp numbers while Endosulfan formulations reduced ants. During the 2004/05 season, large numbers of predators were observed in the aphid trials, especially pirate bugs, coccinellids, lacewing, syrphid and chamaemyiid fly larvae. Most of these were negatively affected by the chemicals used.

This report presents the experimental works and outcomes of my study on the project “IPM

in BollgardII® cotton‐New tools and strategies: A Farming: Systems Approach” under the

agreement between NSW Department of Primary Industries and Cotton Research and

Development Corporation (Project DAN 179C). The project has refined current tools and

developed new tools and strategies to complement beneficial insect’s activities in support of

IPM program on BollgardII® cotton crops as part of a continuous improvement to the

industry’s IPM system.

The aims of this project were:

1. Determine the efficacy of Petroleum spray oils (PSOs) as a stand alone product for

activity against green mirids and aphids;

2. Determine the efficacy of PSOs as adjuvants for full and reduced label rates of synthetic

insecticide for activity against Helicoverpa spp. and green mirids;

3. Assess the effect of PSO residues and sprays on the survival and rate of consumption of

cotton pests by predatory insects in Bollgard cotton crops;

4. Determine and compare abundance of green mirids on Bollgard crops interplanted with

and without lucerne strips or placed adjacent to lucerne blocks or refuge crops

interplanted with lucerne strips;

5. Evaluate the efficacy of a new myco‐insecticide for activity against green mirids on

Bollgard cotton crops;

6. Determine strategic use of Magnet (moth) attractant on Bollgard II® cotton crops on the

level of Helicoverpa spp. production and management on conventional cotton crops

7. Determine strategic use of Magnet (moth) attractant on Bollgard II® cotton crops and

PSOs on conventional cotton crops on the level of Helicoverpa spp. production and

management of Helicoverpa spp. on the conventional crops

8. Assist in the review of the cotton industry IPM guidelines.

To achieve these aims a series of laboratory, mesh house and large scale field experiments

were conducted in irrigated commercial cotton crops in the lower, Gwydir and Macintyre

valleys in New South Wales and Queensland between July 2004 and June 2007. Plot sizes

ranged from 3 to 400 hectares.

In studies to assess the efficacy of Petroleum spray oils as a stand alone and in mixtures with

reduced rates of synthetic insecticides, the results showed that application of 2% v/v PSOs

by themselves can cause direct mortality to Helicoverpa spp. larvae particularly 1st ‐3rd instar

stages and green mirid adults and nymphs. The addition of 2% v/v of either Biopest or

Canopy® oil to ½ rate insecticides achieved similar control of Helicoverpa spp and green

mirids as 1% PSO + full label rate insecticide and also the full label rate insecticides alone. In

terms of conservation of predatory insects in the cotton cropping system, the application of

PSO mixed with ½ label rate of insecticides minimised the impact of the insecticides on

beneficial insects compared to the full label rate or 1% plus the full label rate of the

insecticides. The prey consumption rate of the predators that survived PSO sprays alone or

in combination with reduced rate of insecticides was not affected.

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In the study to assess the use of trap crops to manage green mirids on BollgardII® cotton

crops, the results showed that green mirids prefer sunflower and lucerne to cotton crops.

However, sunflower dries off in January when cotton plants are in their peak squaring,

flowering and boll setting stage. The drying of the sunflower crops will force green mirids to

move to the cotton crops to cause damage and yield loss. In contrast, lucerne crop has a

permanent growth and can maintain the mirids throughout the cotton growing season

provided the lucerne is kept fresh by watering. The study showed that lucerne crop can trap

and manage green mirid numbers in adjacent BollgardII® cotton crop to a distance of 250‐

300 metres away from the lucerne crop.

One of the most significant and major breakthroughs in this project is the development of

two fungal insecticides (BC 639‐Metarhizium spp and BC667 – Beauveria spp), for the control

of green mirids, Helicoverpa and aphids. The result of the study showed that application of

0.5‐1.0L/ha of either fungus can cause over 70% mortality of green mired adults and

nymphs. In most field trials, application of BC639 and BC667 at rates of 0.5‐1.0 L/ha reduced

densities of green mirid adults and nymphs from 3.5 per metre to zero within 7 days after

treatment. The efficacy of the fungal insecticides applied at these rates against green mirid

adults and nymphs was the same as Fipronil applied at the label rate.

The fungus killed green mirids within 3‐4 days after application. The fungus is selfperpetuating

and can cause secondary infection to green mirids whereby the death of

infected mirid or insect can produce spores which will then infect and kill live insects. The

fungus is effective against soft bodied insects (mostly pests) so that hard bodied insects

(mostly key predatory insects) are often saved. In field trials, I found no significant

differences between the number of predatory beetles, bugs, lacewings and spiders per metre

in plots treated with fungal insecticides and unsprayed (control) plots. In contrast, the

number of predators recorded on plots treated with the fungal insecticides was significantly

higher than the commercial insecticide (Fipronil). This indicates that the fungal insecticide is

“softer” than Fipronil.

A Commercial partner has been identified and a commercial agreement between the Cotton

Research and Development Corporation, NSW Department of Primary Industries and the

Commercial partner will be signed on 29 February 2008.

In studies to determine the strategic use of Magnet® (moth attractant) mixed with

insecticides to attract and kill Helicoverpa moths on BollgardII® cotton crops, the study

showed that the Magnet® formulations killed Helicoverpa spp. (moths) resulting in reduction

of Helicoverpa moth populations on adjacent conventional cotton crops located 0.5 to 1 km

away from the “treated” BollgardII® cotton crops. This strategy resulted in a pest control

saving of $11.40 per ha in the “treated” over the “untreated” conventional cotton crops.

The study also showed that application of Magnet® formulation onto the Bollgard cotton

crops attracted moths from the environment to the treated area and the residual moths that

could not reach the Magnet® treated zone before the Magnet® odour dissipated stayed in

the conventional cotton crop that was closest to the “treated” BollgardII® crops and laid

eggs. By applying Petroleum spray oil (PSO) on the conventional cotton crops, the number

of Helicoverpa moths, eggs and larvae per metre on the conventional cotton crops treated

with PSO was significantly lower than the conventional cotton crops not treated with the

PSO. The explanation given was that application of PSO on the cotton plants suppressed the

quantity of airborne volatiles released by the cotton plants resulting in lower egg and larval

numbers on the PSO‐treated plants.

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The project also provided information and assisted in the review of the Cotton Industry IPM

guidelines in 2005. The IPM guidelines was launched by the Hon. John Anderson MP, and

Deputy Prime Minister of Australia on 18th February 2005. New information on the use of

PSO in managing pests on cotton, trap cropping and predator to beneficial insect ratio has

been incorporated into the guidelines.

Overall, the project has developed two new IPM tools (BC639‐ Metarhizium spp. and BC 667

– Beauveria spp) for the control of green mirids, Helicoverpa spp. and aphids. The project has

also developed other alternative pest control tools (lucerne strips, Petroleum spray oils ‐ as

stand alone and adjuvavants with reduced label rates of insecticides) as additional tools for

the industry’s IPM program. The project has also developed management guidelines for use

of lucerne strips, PSOs and Magnet (moth) attractants for cotton growers to manage both

their Bollgard and conventional cotton crops. Thus, the project has addressed the issue of

sustainable use of pesticides in the cotton industry.

The project has linked with Industry Development Officers (IDOs), reseachers and

consultants to provide information and refine the cotton IPM guidelines.

In conclusion, the project has been very successful in developing two new biopesticides

(fungi) that can be used by cotton growers to control green mirids, Helicoverpa spp. and

aphids. Other major project outcomes include enhancement of IPM programs on both

transgenic and conventional cotton, reduction of insecticide sprays, delay insect resistance to

synthetic insecticide and transgenic cotton and improve profitability, competitiveness and

sustainability of the cotton industry.

The ARLP, like the Rural Research and Development

Corporations is one of Australian agriculture's great

success stories. It works because it is a partnership,

a shared goal of industry and government

Over the past ten years, many of our rural

industries have experienced productivity gains

that have occurred through sound investment

into programs such as the ARLP by the Australian

Government and its Research and Development

I am proud that my Department of Agriculture,

Fisheries and Forestry has been a long term

supporter of the ARLP. Strong partnerships and

support exists among the Research and

Development Corporations. These partnerships

allow emerging rural leaders to help our rural

industries build a sustainable future for Australia

The Australian Cotton Industry has been lauded as one of the success stories of Australian agriculture, noted for its technical innovation and its ability to recognise the challenges that confront it and establishing strategies to address them.

Specialist knowledge and information was gained on many different aspects of whitefly ecology, biology and management including findings from Australian and international research programs. Although Damien was the only CCA representative attending the event, other crop consultants and agronomists (and other industry representatives) will be able to benefit from his participation through the distribution of the report via the CCA e-newsletter. The report has already been provided to the CCA Board and a representative of CRDC

Differential cotton products are highly demanded by customers to provide them with protection, while maintaining comfort during the service of the products. Protection against hazards and threats from environment, such as water, oil, chemicals, biological substances, is necessary for daily routine and for people with special missions. For this reason, protective clothing has been widely used for firefighters, mining workers, military forces and athletes. Coating is a very effective technology to bring extra functions to textiles, especially for performance textiles and coloured protective clothing the coating of extra layer is the core mechanism. Fluoro-based polymers or compounds were applied to fulfil the protection requirements of performance textiles, however, the toxic by-products from synthesis of those fluorobased chemicals have created threats to health and environment. Eco-friendly polymers are being sought for replacing the fluoro-based chemicals in the development of coating. As an example, polyurethane has been widely applied to coat textiles for different purposes. Even though the water proof membrane (WPU) and polymeric coating (TPU) can provide protection to cotton fabrics, it is important to develop versatile protection mechanism to coloured cotton fabrics. A combination of WPU using different pigments and TPU with different dyes have been used to provide a versatile protection and resolve this challenge.

This project focused on a coloured coating of waterborne polyurethane (WPU), polydimethylsiloxane (PDMS) and trimethylated silica (TMS) on cotton fabrics by pad-knife-pad method. Different dyes/pigments were applied with TPU paste to bring colour to the coating.

The researcher was enrolled as a Research Assistant in the research group at RMIT University. The researcher conducted the experiments of coating and performed related characterisation's on the surface properties and protections of both the colour coated fabrics and TPU dyed fabrics. The data colour testing was employed to compare the shade of dyes with the pigments on the coloured fabrics. It has been found that the colour coated fabrics of WPU-PDMS-TMS has brought hydrophobicity and repellency against water, oil, chemicals and aqueous liquids. Comfort properties have also been assessed using thermal resistance and moisture management property tests. The coating technology has the potential to apply coloured cotton in protective clothing and performance textiles in different areas including military, mining and outdoor sportswear.