This travel was undertaken to participate in the CRDC one day forum on 'Soil Constraints' held at Moree on the 14th July.

The development and release of SIOKRA, the new okra-leaf variety, has created considerable interest with respect to pest management. The altered leaf shape of this cultivar, which results in a more open canopy, has led many growers to expect differences in its attractiveness to Heliothis in particular, and to other insect pests in general. Indeed, many growers and consultants have commented on the apparent reduction in Heliothis and in the number of sprays applied to SIOKRA crops. The SIRATAC database confirms this trend.

Heliothis spp. have two main attributes which give rise to their pest status and make them difficult to manage (see Fitt this volume). Firstly both species exploit a wide range of host plants in addition to cotton, including most crops (eg. sorghum, sunflower, maize, and many others), and many weeds. Many of these hosts are extremely important in the seasonal dynamics of Heliothis populations and past research has identified the sequence in which they are used from spring through to autumn. These hosts represent the source of many of the moths which colonise cotton crops, but at present we have no way of estimating the relative importance of intercrop movement in the dynamics of Heliothis on cotton or the contributions of different crops to the local population. The second important attribute is that Heliothis moths are highly mobile.

Attendance and presentation of a scientific research paper at the joint conference of American Societies of Agronomy, Soil Science and Crop Science at Phoenix, Arizona, USA (https://www.acsmeetings.org). Additionally, meetings with University of Arizona and USDA-ARS staff (Maricopa Research Centre) conducting research on alternative sources of irrigation water and cotton farming systems in saline and sodic soils and then on return, updating University of Southern Queensland(USQ) researchers on current research on using wastewater for irrigation.

The travel undertaken consisted of (a) Pre-conference tours on regional pedology (4-5 November 2016) and irrigated cropping systems of central Arizona (6 November 2016). (b) Attend and present paper at the international joint conference of the American Societies of Agronomy, Soil Science and Crop science. Approximately 4000 oral and poster papers were presented at the conference which was attended by around 6000 delegates. (c) Visit Arid Lands Research Centre of the University of Arizona and the USDA Agricultural Research Service. I was hosted by Dr. Clinton Williams, soil scientist at the centre. Dr. Williams’ research focusses on issues related to saline water and effluent irrigation. (d) Visit to University of Southern Queensland for discussions with Dr. Jon Bennet and Aditiya Dang.

The resulting outcomes from Dr Hullagale's participation were lengthy

(1) Exposure of my research results to an international audience (number of attendees at this conference usually exceeds 4000). The feedback received will enhance formulation of future research activities.

(2) Interaction and discussions with soil scientists and agronomists working on alternative irrigation water sources and irrigated cotton farming systems in saline/sodic soils of semi-arid and arid zones will facilitate future collaborations.

The above topics are highly relevant to Australian cotton farming systems. The reduced availability of irrigation water due to drought and legislation, and its increasing cost suggests that alternative sources of water, its management and impact on soil quality will be of increasing importance in the future. Sodicity is common, and transient salinity during drought years is not uncommon in Australian cotton soils.

(3) Current USQ project on wastewater irrigation refined in the light of recent US research on wastewater irrigation.

Of the five species of Heliothis in Australia, only two, Heliothis armigera and H. punctigera are major economic pests. They are clearly the major pests of cotton in all production areas. My comments in this paper refer only to these two pest species.

Reducing the costs of pest management may be looked at in two ways. These are the actual reduction of chemical costs which must be balanced against the need to maintain or enhance yield. Any discussion of cost saving must admit that it is the gross margin we are seeking to hold or increase. This may not actually decrease chemical costs but it aims to improve profit. In my own shorter season area, the upper Namoi, I dent think we should consider reducing the number of sprays, except with Siokra. There appears to be potential to leave out one or two early sprays in the main cotton areas, and even increase yield.

Experiments were conducted to determine whether on cotton, Rutherglen Bug and Grey Cluster Bug were able to survive, develop and reproduce. Their ability to damage cotton was also assessed.

Traps baited with sex attractants ( 1 pheromone 1 traps) are presently being used by a number of farmers in Central Queensland to monitor P. scutigera populations and for timing insecticide sprays. However, there is conflicting evidence in the published literature as to the best type of attractant to use. Rothschild (1975) concluded that the Z,Z isomer of 7, 11-hexadecadien acetate (7 , 11-16 : Ac) was adequate for monitoring purposes and was used in subsequent experiments (Rothschild 1983) . In contrast, Flint and Stone (1985) found that traps baited with a 9:1 ratio of Z,Z to Z,E isomers caught significantly more moths than Z,Z only baited traps .

Technological innovations in the cotton industry are advancing mechanisation and seeking to create improved efficiencies of labour and energy inputs. These innovations are often adopted rapidly without specific knowledge to support the adoption. That is to say, innovations are often adopted on the face value of a proclaimed efficiency. Thus, the farming system impact of these innovations is not well understood in the majority of cases. While the cotton industry has developed and endeavours to use best management practices (BMP) for farming system components (including soils and water), an impact assessment framework for evaluating the impacts of these new technologies on the whole farming system does not exist. The rapid adoption of the round bale (RB) picker presents an opportunity to investigate the specific effects of this new technology, and in doing so, inform development of an impact assessment framework applicable to other technological innovations for cotton.

Of particular concern is the potential for delayed impact of RB pickers on sustainable management and production, particularly from a soils perspective. These machines are designed to provide energy/labour efficiencies (the current driving force), but impacts such as increased compaction resulting in increased soil-bed preparation costs may emerge in subsequent seasons. The major impact of machinery on the soil is compaction, and not surprisingly ‘SOILpak For Cotton Growers’ declares compaction as a yield limiting factor in cotton production. Compaction has historically been managed through various techniques, such as controlled traffic farming (CTF) and minimum tillage. In the case of the round bale picking system, these machines eliminate the need for the boll buggy by preparing round bales on-the-go, but the trade off is an increase in total machine weight. This raises concerns of increased soil compaction, especially under moist soil conditions generally experienced in irrigated fields, or during wet cotton seasons. The ability of the soil to carry the increased weight under marginal traction conditions may narrow the harvest windows. Furthermore, given the adoption rate, it is unlikely that optimisation of machine performance within individual farming systems has occurred. The potential to provide further impact offset capability is real and should be optimised. The question is then raised: “Is this machine being utilised optimally and do the economic efficiencies offset potential field impacts?”

As the uptake of the RB picking system has been widespread and rapid, it is not a matter of whether or not the industry should adopt this technology, rather a process of determining its impacts, evaluating impacts against previous harvesting systems, and developing strategies to optimise operating performance. By engaging the industry in discussion and reviewing current information on harvesting system implementation and performance, this project seeks to determine a series of indicators that can be measured in-field to assess field impacts and machine performance. In doing so, the basis of an impact assessment framework will be constructed and refined over several cotton seasons of in-field monitoring of RB picking systems.

The Push Pull Strategy (P.P.S.) is a method of sensory manipulation of pest insects originated at the University of Queensland. It proposes to manage the behaviour of pests by making their food less palatable with allomones and simultaneously attracting the "frustrated" insects to killing lures laced with kairomones.