Background Art Since the advent of agriculture, fungus pests have plagued farmers, bringing reduced crop yield, and on occasions, complete crop failure. While fungus pests have no doubt co-evolved with plants, the density and uniformity of crop planting has provided an opportunity for infective fungi which would not have been available in the wild on the same scale. In response to this problem, the discovered properties of various compounds have been brought to bear, elemental sulphur perhaps being the oldest known to mankind.

Elemental sulphur has long been known as a fungicide, and has typically been applied as a powder or in liquid form. In addition, lime-sulphur is often used as a foliar fungicide. Other fungicides include Bordeaux mixture, which is a mixture of copper sulphate and lime (calcium hydroxide), which is also effective as a bacteriocide.

Organic chemical based fungicides are considered more effective than sulphur or copper based preparations. Examples of organic chemical based fungicides include the benzimidazole fungicides such as thiabendazole, benomyl, and thiophanate methyl, and metalaxyl. However, it has been observed that some fungus develops resistance to repeated application of the same or related fungicide. There are also concerns in relation to toxicity of organic chemical based fungicides, occupational to those engaged in growing crops, and also environmentally. There is also a growing awareness among some consumers

who prefer to purchase so-called"organically grown"produce, not to be confused with"organic chemical", referred to above. Such consumers prefer to purchase produce that has not been grown with the aid of pesticides and other artificial chemicals.

Various other compounds have been trilled as fungicides, but found wanting in some respects. For example, in Bulletin No 22-August 1891, published by the Experiment Station (Botanical Department) of the Kansas State Agricultural College pages 73 to 93, there are described trials involving use of potassium sulphide as a fungicide. One trial which involved soaking oat seed prior to sowing, in an aqueous solution of potassium sulphide demonstrated effective fungicidal properties represented by increased yield in the resultant crop.

However, a study of foliar application of an aqueous solution of potassium sulphide to leaves of a wheat crop, demonstrated no effective fungicidal properties whatsoever.

The preceding discussion of the potassium sulphide trials is intended to facilitate an understanding of the present invention. However, it should be appreciated that the discussion is not an acknowledgement or admission that any of the material referred to was part of the common general knowledge in Australia as at the priority date of the application.

It is an object of the present invention to at least provide an alternative to hitherto known fungicides.

Throughout the specification, unless the context requires otherwise, the word "comprise"or variations such as"comprises"or"comprising", will be understood to imply the inclusion of a stated integer or group of integers but not the exclusion of any other integer or group of integers.

Disclosure of the Invention The invention has arisen during the course of experiments to test whether a compound used in the destruction of cyanide and precipitation of heavy metals in

the mining industry might be an effective fungicide for use in wheat crops.

During the course of this, it was found that while the composition, namely an aqueous solution of sulphur and sodium hydroxide, was effective as a fungicide, the sodium present in the composition was not considered desirable in an environment in which land salination features prominently as a problem.

The inventor then considered whether potassium hydroxide might substitute for sodium hydroxide. Potassium hydroxide would not normally be utilised in a mining application due to the additional expense when compared with sodium hydroxide. Not only did the inventor find that an aqueous solution of sulphur and potassium hydroxide was effective as a fungicide, but also that the development of the plot of trilled crop was considerably more advanced than that of control plots having no fungicidal treatment and crop having standard fungicidal treatment. Furthermore, the effectiveness of the composition as a foliar applied fertiliser and fungicide far exceeded expectations based on tests with potassium sulphide and potassium sulphate, neither of which show any significant uptake through foliar application.

In accordance with the invention there is provided a fungicide and fertiliser composition comprising a fusion of potassium hydroxide with elemental sulphur in proportion of at least 60% by weight of the potassium hydroxide (excluding any water of crystalisation or hygroscopically absorbed water). The fusion is believed to be the reaction product of potassium hydroxide and sulphur, in effect a potassium polysulphide.

Also in accordance with the invention there is provided a fungicide and fertiliser composition concentrate comprising an aqueous mixture of potassium hydroxide and elemental sulphur in proportion of at least 60% by weight of the potassium hydroxide (excluding any water of crystalisation or hygroscopically absorbed water present in the potassium hydroxide). Such a mixture will comprise preferably a saturated solution of the reaction product of KOH and elemental Sx or alternatively where excess sulphur is present, a slurry of sulphur in a preferably saturated solution of the reaction product of KOH and elemental Sx. A

saturated solution is preferred in order to maximise the strength of the concentrate and to minimise shipping costs.

Preferably said fungicide and fertiliser composition concentrate comprises an aqueous solution of said potassium hydroxide and said elemental sulphur in an amount of water being at least 200% by weight of the potassium hydroxide (excluding any water of crystalisation or hygroscopically absorbed water present in the potassium hydroxide). Water in an amount of at least 200% by weight of the potassium hydroxide (excluding any water of crystalisation or hygroscopically absorbed water present in the potassium hydroxide) provides a saturated solution at normal ambient temperature.

Preferably the elemental sulphur is present in proportion of at least 70% by weight of the potassium hydroxide (excluding any water of crystalisation or hygroscopically absorbed water present in the potassium hydroxide).

Preferably the elemental sulphur is present in proportion of at least 80% by weight of the potassium hydroxide (excluding any water of crystalisation or hygroscopically absorbed water present in the potassium hydroxide).

Preferably the elemental sulphur is present in proportion of at least 90% by weight of the potassium hydroxide (excluding any water of crystalisation or hygroscopically absorbed water present in the potassium hydroxide).

Preferably the elemental sulphur is present in proportion of about 100% by weight of the potassium hydroxide (excluding any water of crystalisation or hygroscopically absorbed water present in the potassium hydroxide).

Furthermore, in accordance with a preferred feature of the invention there is provided a ready-to-use foliar applied fungicide and fertiliser preparation comprising a mixture of one part of said aqueous solution and from 1000 parts to 3000 parts of water.

Preferably the fungicide and fertiliser preparation comprises a mixture of one part of said aqueous solution and from 2000 parts to 2500 parts of water.

Preferably the fungicide and fertiliser preparation comprises a mixture of one part of said aqueous solution to about 2250 parts of water.

Also in accordance with the invention there is provided a method of providing fungicidal treatment and fertiliser to a crop, comprising spraying said ready-to- use preparation on said growing crop.

Preferably said ready-to-use preparation is sprayed in an amount of from 30 to 60 litres per hectare.

Preferably said ready-to-use preparation is sprayed in an amount of about 45 litres per hectare.

Preferably said ready-to-use preparation is sprayed in an amount of about 2 litres per hectare of fungicidal composition concentrate formed from 1 part by weight KOH (as anhydrous), 1 part by weight elemental sulphur and two parts by weight water.

Brief Description of the Drawings A preferred embodiment of the invention will now be described in the following description of method of making the fungicide composition, and suggested application for the fungicide composition.

Best Mode (s) for Carrying Out the invention The following description describes preparation and use of a combined fungicide and foliar fertiliser in preventing fungal infestation in wheat crops which can if left unchecked, lead to losses in crop yield, or in the worst instance, crop failure.

The combined fungicide and foliar fertiliser was prepared by dissolving one kilogram of potassium hydroxide in 2 litres of water and then dissolving one kilogram of elemental sulphur in the potassium hydroxide solution. The dissolving of potassium hydroxide in water is very exothermic, and raises the temperature of the solution to around 90°C. The sulphur is added to this hot solution, in which it appears to undergo a reaction where it dissolves and evolves a small amount of gas. The resultant composition concentrate was a slightly alkaline solution of 25% sulphur and 17.5% potassium.

Two litres of the composition concentrate was made up to 45 litres with water, to produce a ready-to-use product at a typical foliar application concentration. The 45 litres of ready-to-use product was sprayed on a one hectare test plot of pre- emergent crop. At four weeks after spraying, the sprayed plot was compared with a control plot of one hectare having no treatment, and the remainder of the farm crop which was subjected to the normal regime of fungicide treatment. The normal regime involved application of fungicides, typically FOLICUR TM from Bayer Corporation and TILT 250 TM from Syngenta Crop Protection Inc, when the wheat crop comes into ear, or when fungal infection was observed on the crop.

The resultant application rates are 650 grams of sulphur and 450 grams of potassium per hectare as a foliar application. On observing the plots and the remainder of the farm crop some four weeks after spraying of the test plot there was no evidence of fungal infestation in spite of the need to spray for fungal rust infestation on the remainder of the farm crop, and despite also the presence of rust on neighbouring properties, which necessitated the neighbours having to spray for rust.

Furthermore, and unexpectedly, the test plot was found to be 1 to 2 weeks more advanced than the untreated crop and the remainder of the farm crop over a period of 3 to 4 weeks since the application. This was manifested by all of the test crop being in ear while the untreated control plot and the remainder of the farm crop was only just emerging. There appears to be a good chance of significantly higher yields on the test plot.

In commercial applications it is envisaged that the combined fungicide and foliar fertiliser composition concentrate can be manufactured in commercial quantities by dissolving one tonne of potassium hydroxide in 2000 litres of water and then dissolving one tonne of elemental sulphur in the resultant potassium hydroxide solution. The product can be stored in steel or plastic drums, and supplied in bulk to farmers. In use, the farmers can then dilute it to typical foliar application concentrations by taking 200 litres of concentrate and diluting it to 4500 litres in the tank of a crop sprayer, and then spraying the pre-emergent crop with a conventional boom spray.

A preferred rate of application of 2 litres per hectare of the concentrate, or 45 litres per hectare of the made-up product is expected to be effective. The time of spraying at the pre-emergent stage when leaf growth is near maximum is believed to be the best.

The inventor also tested the composition as a foliar applied fertiliser and fungicide on oats, albeit on a much smaller scale than the above described wheat trial, and found that similar results were obtained.

It has also been found that urea may be added to the saturated solution and to the ready to use preparation without reacting with the KOH and Sx reaction product. As a consequence, urea may be added in order to provide a nitrogen component to the fertiliser. While other additives have not been tested, the addition of other additives is considered to be within the scope of the invention.

It should be appreciated that changes may be made to various features in the above described embodiment without departing from the spirit and scope of the invention, and that the invention is not limited to the specific embodiment described herein. While the trial centred around a wheat crop, the method is equally suitable for any cereal, and other plants such as canola.