The initial BMP Manual focussed on pesticide use. This project aimed to explore the requirements for expanding the focus of the BMP manual, and the BMP program, to all relevant natural resource management issues. These requirements included both the development of the practical information required to address the identified natural resource issues, as well as the relationship of the BMP program to other initiatives (both Government and other agricultural industry initiatives)

The aim of the project was to provide cotton advisers and leading growers in the Hillston district (lower Lachlan Valley, NSW) with the latest information about soil assessment and management for the sustainable production of inigated cotton.

The workshop also provided an opportunity to train recently appointed Industry Development Officers,

The value of decision support packages such as SOILpak for cotton growers, third edition and NUTRlpak was emphasised.

WEEDpak synthesizes the results of extensive research on IWM in Australian cotton farming systems from research . The WEEDpak manual includes extensive reference material to help identify weeds, an important first step in IWM. WEEDpak then discusses a number of other issues involved with IWM including herbicide resistance, herbicides and their application, farm hygiene, the control of volunteer cotton, and weed control in rotation crops. Since the main thrust of IWM is management, WEEDpak , the management of specific problem weeds

Fibre quality management includes on-farm and post-farm gate practices. Variety

selection, irrigation management, crop nutrition management, disease management, pest

management, climatic and weather conditions, harvesting, transport and ginning practices

can all affect fibre quality. Management practices and environmental conditions up to the

point of harvest determine whether the valuable attributes of the selected variety are

realised. Practices from harvest onwards determine whether these fibre qualities are maintained.

The overall quality of the Australian cotton crop is high and continually improving.

While each year's crop generally has one or two quality aspects that would idealIy be better, Australia has a well-deserved reputation for producing and delivering a consistent, high quality product well suited to the needs of spinners. Thus there is no over-riding quality concern that cries out for immediate attention, or which a failure to address would cause immediate marketing problems. Nonetheless, a co-ordinated, formal approach to fibre quality management will help ensure that at a minimum, Australian cotton will continue to occupy its current market position.

It is recommended that the Australian cotton industry undertake to address quality management issues in a coordinated way, through a formal industry program.

Screening of native whitefly from host specificity testing list continues with the following results of host testing of Eretmocerus hayati.

The following whitefly species have been tested:

Lipaleyrodes euphorbiae - no parasitism

Lipaleyrodes atriplex - less than 20% parasitism, adult parasitoids die upon emergence

Bemisia afer -no attack

Bemisia gigantea- no attack

Bemisia sp (saltbush) - test running

Additional species of whitefly tested;

Dumbletoniella eucalypti- no attack

Aleurocanthus spiniferus- no attack

Bemisia subdecipiens - site detected, bushfire destroyed site

Bemisia giffardi- source detected, collection in progress.

Due to silverleaf whitefly expansion in other vegetable crops and outbreaks in commercial production

regions in Qld, the industry has requested meetings and information sessions. For that reason technology

transfer activities were initiated. A large scale tomato trial was conducted to evaluate the best insecticide options combined with the use of

damage thresholds. The two best management options (BMO) were tested with two industry standard

practices.

Four large silverleaf whitefly meetings and information sessions were conducted in Qld

covering the major vegetable production regions. The subject areas covered in the meetings included

insecticide permits, best chemical use strategies, information on new chemistry, crop monitoring, spray

threshold, resistance management, parasitoids and best farm practices. All these meetings were well

attended by the industry and the participants included vegetable growers, crop consultants, chemical

company representatives, resellers, researchers and extension officers. Presentation notes, permit

information and handouts. Best use of IGR against SLW in vegetable crops, and sample spray programs were distributed to participants.

One third of global food and fibre is produced by irrigation agriculture and it is predicted that this will rise by 50 % in 2040 (Rhoades et al. 1992 ). Management of the irrigated land is therefore an important factor in ensuring sustainable production. However, in the Murray-Darling Basin of Australia, inefficient irrigation practices have resulted in the creation of perched water tables, waterlogging, rising water tables and salt mobilisation. In NSW alone 40% of irrigated areas is prone to shallow water tables and this is increasing (Murray-Darling Basin Commission, 1999 ). The common cause of degradation is deep drainage (DD) or groundwater recharge, which is the process whereby water passes through the root-zone into the water table. With the increasing pressures on water resources and expectations from the community regarding natural resource management it is necessary that methodology be developed for identification of where salinisation has occurred, what are the processes, which have created these problems and determine where improvements can be made in natural resource management.

Host Plant Resistance of Cotton genotypes. Australian cotton is attacked by a diversity of insect pests. While transgenic Bt cottons will increasingly provide control of Helicoverpa, conventional host plant resistance remains a valuable component for tolerance to other pests and to “support” the by enhancing background levels of resistance. This proposal sought to continue research on host plant resistance from the previous project (CSE59C Evaluation of Pest Resistance in Australian Cottons) through: (i) continued field and laboratory studies of a range of cotton genotypes; (ii) increased emphasis on sucking pest resistance, particularly aphids and mirids; and (iii) research on the biochemical changes in cotton associated with induced defences, compensation ability and the efficacy of transgenic cottons.

CRDC's Annual Operational Plan for 2019-20 (AOP): the second annual operational plan under the CRDC's Strategic RD&E Plan 2018-23.

Regeneration is poorly understood for most common riparian plant species of inland Australia, despite their ecological and cultural significance, widespread distributions and concern, in many places, over their condition and status. Where research has been conducted, it has tended to focus on effects of flooding and drought on regeneration, often with a view to informing water management at catchment or wetland scales. In contrast, little attention has been given to influences of local factors on recruitment, or their effects in determining regeneration responses to hydrological conditions. With respect to farm-scale management, however, it is the local factors (e.g. canopy and ground cover or grazing pressure) where interventions can best be targeted to maintain or improve riparian ecosystem condition.

This project will investigate the influence of local, farm-scale factors on the regeneration of common riparian plant species from the northern Murray-Darling Basin (e.g. river red gum, coolibah, river cooba, lignum). A range of glasshouse experiments will be conducted to examine the effects of a suite of local environmental factors on germination and seedling establishment responses to broad hydrological conditions (e.g. flooding, waterlogging, drying). Local, farm-scale factors to be explored may include: i) canopy cover (i.e. shade); ii) various ground covers (e.g. litter, wood, sediment); iii) grazing pressure (e.g. trampling, mechanical damage, clipping), iv) sediment characteristics (e.g. soil type, burial) and v) weeds (e.g. competition with Noogoora burr). Final experimental treatments will be determined in consultation with Stacey Vogel and the CRDC in relation to those most likely to be influenced by riparian management practices.

The project will utilise an existing seed collection which will be supplemented with field collections as necessary along with any additional materials required with which to conduct experimental treatments.

Results will be interpreted with respect to best management practices and monitoring guidelines for cotton farms with riparian lands.

Helicoverpa punctigera, along with Helicoverpa armigera, are major pests in Australian cotton. They are currently controlled using “Bt cotton” which contain genes derived from the bacteria Bacillus thuringiensis, that produce proteins toxic to Helicoverpa. While most effort has focused on preventing Helicoverpa spp. developing genetic resistance to these toxins, laboratory studies have shown that larvae which are not resistant are able to tolerate low to medium levels of toxin. This “induced tolerance” could lead to larvae surviving on Bt cotton without being resistant, and it could provide a stepping stone to the development of resistance. While Helicoverpa are known to develop some tolerance after one generation of exposure to Bt toxins, we did not know whether exposure is required throughout the entire larval period or only during particular instars. The aim of this summer project was to test if exposing the larvae Helicoverpa punctigera at different larval stages to 2% or 5% toxin concentrations of the discriminating dose of Cry1Ac toxin (used by CSIRO’s Resistance Team) would affect larval development and lead to tolerance in their offspring.

The results confirmed that after exposing only one generation of larvae to low levels of Cry1Ac toxins their offspring were able to tolerate higher levels of Cry1Ac than the controls. In addition we found that larvae exposed to Cry1Ac in early instars overcompensated their growth once they fed on non-toxin diet, and those exposed as late instars actively tried to avoid the toxin and developed into smaller moths. While the offspring of larvae exposed to 5% toxin as late instars showed the most tolerance, those exposed to 2% toxin as late instars also produced significantly more tolerant offspring. These results indicate that the critical period for the development of tolerance is late in larval development.

These results have implications in respect to Bt cotton efficacy, and could have implications in respect to the placement of refuges. They suggest that larvae moving off other crops and completing their development in Bt cotton could produce offspring at least as tolerant as those completing their development within the Bt crop. Therefore ideally refuges need to be far enough away from Bt cotton to avoid older larvae moving into the cotton.