agtechfocus_07_Wheat (1).pdf

CHAPTER 7 Shutterstock.com/maxbelchenko Wheat CHAPTER SUMMARY Wheat is one of the most...

CHAPTER 7 Shutterstock.com/maxbelchenko Wheat CHAPTER SUMMARY Wheat is one of the most important crops grown in Australia. It is grown mainly for the export market to make products such as bread, pasta and noodles. Some wheat is grown for livestock feed and can be used as pasture for grazing, which is then harvested for grain. Many aspects of the environment must be managed to ensure a high-quality grain yield. There is much demand for wheat worldwide and the challenge for growers will be to sustainably grow a crop in a constantly changing climate. How significant is wheat to Australia and the world? How will farmers manage to grow enough wheat to feed a rapidly expanding population within increasing environmental constraints? 162 AG TECH FOCUS 9780170443111 7.1 Introduction Wheat originated in the Middle East and is one of the oldest agricultural crops ever grown. It is one of Australia’s most valuable crops and its biggest grain crop. Wheat is classed as a cereal or grain crop in the family Poaceae. It contains a significant amount of starch that is utilised for energy. It is a staple of most modern diets around the world. Wheat is grown around Australia with the main production areas in Western Australia, New South Wales, Queensland, South Australia and Victoria, and 71% of production exported. Wheat is classified according to protein content and grain size. This determines wheat quality, which then determines its end use. Shutterstock.com/Business plus Figure 7.1 A field of wheat 7.2 Functions and structures Uses of wheat Wheat is an edible grain that is used for both human and livestock consumption. Wheat has been a human staple for thousands of years and is one of the first crops of early agriculture. It has evolved to provide a variety of uses for markets all over the world and is used commercially in the following ways. 1 Food production – wheat is a versatile grain that is milled to provide flour for a number of food products and its unique properties have seen wheat dough used across the globe in products such as: breads and tortillas baked goods such as cakes, pastries and biscuits breakfast cereals dumplings pasta and noodles. 9780170443111 CHAPTER 7 – WHEAT 163 Shutterstock.com/MaraZe Shutterstock.com/Pinkyone Shutterstock.com/blackliz Shutterstock.com/Paul_Brighton CHAPTER 7 Figure 7.2 Food products made from wheat 2 Livestock feed – wheat grain can be used as livestock feed as a substitute for other cereals such as oats and corn. When wheat cannot meet the protein requirements for food production, it is classed as feed wheat and sold as such, but still remains a valuable source of protein for livestock. Wheat in its vegetative state can provide valuable winter forage for vegetative state the livestock in mixed farming enterprises. growth stage of a plant 3 Alcohol and bioethanol production – wheat DID The protein content of where leaves and stems are can be fermented and distilled to create YOU wheat grain can vary from produced, before the onset of flowering and seeding alcohol. The resulting alcohol is neutral KNOW 8% to 15%. in colour and flavour and is used to make spirits such as vodka. Wheat alcohol also has cosmetic and pharmaceutical applications, acting as a preservative, antiseptic and disinfectant. Wheat alcohol can also be used in the production of bioethanol for fuel, a market that is growing rapidly with wheat becoming a major biofuel crop. Wheat plant structure Wheat is an annual plant, classed in the family Grain head of grasses. Like other grasses, wheat grows from a crown base that produces multiple lateral stems called tillers. Tillers provide the wheat plant with leaves for photosynthesis and eventually form an inflorescence from which Leaves inflorescence a flower the grain develops. head that consists of Stem The wheat plant individual flowers arranged in cluster When the first wheat leaf begins to grow, it emerges surrounded by a protective sheath called a coleoptile, which protects it as it pushes through the surface of the soil. The coleoptile is extremely important because it influences the growth and development of the wheat plant, its length determining how Roots well the plant establishes. Figure 7.3 The structure of a wheat plant Wheat flowering The reproductive stage of the wheat plant is when the flower develops after it emerges from a stem, a process called heading. The wheat flower is self-pollinating and the flowerhead, or inflorescence, is made up of a cluster of flowers called spikelets. After the flowers are pollinated, the grain begins to ripen and mature. 164 AG TECH FOCUS 9780170443111 Spikelet (side view) Spikelet (edge view) Floret 4 Floret 3 Rachis Floret 2 Floret 1 Glume 2 Stamens (3) Flag leaf Glume 1 Stigmas (2) Internode Outer husks Palea Ovary Lemma Leaf sheath Floret Node Figure 7.4 The wheat flower The wheat grain The wheat seed is classified as a grain or kernel and is the fruit of the wheat plant. Wheat grains WS consist of approximately 70% carbohydrate, of which 97% is starch. A wheat grain is made up of Homework the parts shown in Table 7.1. Review your knowledge Table 7.1 Parts of a wheat grain about the structure of a wheat plant and grain with the worksheet on Seed coat Outer protective coating of seed, generally removed during the milling process NelsonNet. Endosperm Tissue that provides the seed with the energy required for germination. It makes up a large proportion of the grain and stores starch and protein. Aleurone Protein layer that surrounds the endosperm. It secretes enzymes that break down starch in the endosperm. Embryo Contains all the main structures of the plant and is the germinating part of the seed Wheat grain or berry Commercial products Vertical section Their location in the berry Brush Pericarp Bran Aleurone Pollard Endosperm White flour Flour plus Embryo or gluten germ Germ Figure 7.5 The wheat grain 9780170443111 CHAPTER 7 – WHEAT 165 Red vs white grains CHAPTER 7 Wheat grains are classified by their colour. While most wheat grown for the commercial market in Australia is white grained, red grains are commonly seen in wheats grown for livestock feed. In the northern hemisphere, red-grained varieties are grown more extensively and are used in wholemeal or ‘whole wheat’ products. DID Poultry farmers favour red-grained wheat to feed their chickens because it YOU results in a lovely golden yolk without the use of feed additives to achieve the KNOW same colour. LET’S REVIEW LOOKING BACK 1 Identify and list products made from wheat. 2 Outline the functions of the main structures of the wheat plant. 3 Explain the importance of the coleoptile. 4 List the parts of a wheat grain. What commercial products are made from each part? 5 Outline the differences between red and white wheat grains. FOR YOU TO DO 1 Explain how the structure of the wheat inflorescence indicates that it is wind pollinated. 2 Draw a series of diagrams that indicate the germination, vegetative and reproductive stages of the wheat plant. Describe the growth and development in each stage. TAKING IT FURTHER 1 Research the milling process. Draw a flow diagram that explains the process. 2 What are the by-products of flour milling and how are they value-added to create other products? 3 Investigate the nutritional differences between white bread and wholemeal bread. Relate these differences back to the physical characteristics of the grain. 7.3 Production Production cycle Wheat is an annual plant, which means its entire lifecycle from germination to reproduction is completed in one growing season. The flowering time of wheat is due to either photoperiod (daylength) or vernalisation (temperature). Spring varieties, the most common wheat sown in Australia, rely on photoperiod to flower, while winter varieties need cold temperatures to flower. The growth stages of wheat shown in Figure 7.6 are determined by temperature and daylength. 166 AG TECH FOCUS 9780170443111 Emergence Tillering Boot stage Heading and flowering Dough stage Seeds Plant produces germinate a number of Stem matures, Seed head emerges Formation of and emerge stems from the nodes (joints) form and flowering occurs wheat grain as seedlings crown base Figure 7.6 The growth stages of wheat Production systems To ensure high wheat yields, a grower must implement appropriate production systems. 1 Dryland wheat farming – the traditional method of growing wheat. It relies on the natural rainfall patterns of the area and is dependent on appropriate variety selection. 2 Irrigated wheat – can be grown under irrigated systems. While regular systems rely on rainfall to meet the crop’s water requirements, irrigation can provide essential moisture, particularly during flowering. This has a direct impact on disease control and yields. 3 Mixed farming system – can provide valuable winter forage for livestock. Winter varieties can be sown early and grazed by livestock throughout the winter. The livestock are taken off before flowering to preserve crop yields. This method has proved effective in high rainfall areas where sheep production dominates. AG IN FOCUS WINTER WHEATS Identify Dual purpose wheats can provide multiple benefits for farmers. Understand Unlike spring wheats, winter wheats can provide valuable grazing pasture during winter and still maintain the ability to produce a high grain yield in summer. Winter wheats require cold temperatures before they can flower, called vernalisation. This allows the plant to be grazed by livestock in the months prior to flowering. The crop provides > 9780170443111 CHAPTER 7 – WHEAT 167 > CHAPTER 7 valuable pasture during the winter months and can be sown earlier, capitalising on late summer rainfall to ensure adequate moisture at sowing for germination. Winter wheats were developed in the late 1970s by Professor Jim Davidson who pioneered the breeding of winter wheats. His aim was to provide farmers in the high rainfall areas of Australia, which were generally limited to grazing enterprises, access to the benefits of growing a high–value crop. As a result significant grazing land, particularly in Victoria, shifted to become valuable cropping areas. Winter wheats were originally bred without awns that made them more palatable to livestock. Initially awn a hair-like spine that the breeding program focused on wheats adapted to the waterlogged conditions grows on a wheat head. experienced in the high–rainfall areas that were not suited to cropping. Some wheat species are awn-less Alamy Stock Photo/Natalia Kuzmina Alamy Stock Photo/Cameron Leys Figure 7.7 Winter wheats have no awns to make them easier for livestock to eat. Today, winter wheats remain a valuable resource in mixed farming areas and breeding has focused on disease-resistant, high-yielding white grain varieties. These give farmers the opportunity to sow early when conditions are ideal. This ensures that flowering occurs late enough to avoid frost, but early enough to avoid heat stress, all while maximising vegetative growth for grazing prior to harvesting the grain. Discussion 1 Describe the key features of a winter wheat breed. 2 What are the advantages and disadvantages of a grazing–cropping rotation on the farm environment? 3 Farming can be a high-risk business. Is diversification worth the additional inputs required by the farmer? Why or why not? 4 An effective pasture is one that has an appropriate mix of plant species for biodiversity and livestock nutrition. What are the implications of livestock grazing on single type of pasture? Aboriginal production systems WS Aboriginal peoples were the first to successfully grow, manage, harvest and process grain crops, with evidence extending back approximately 40 000 years. Native millet (Panicum decompositum), Homework a perennial grass species, was grown across Australia in areas known as the Aboriginal grain How do Aboriginal production systems compare to other belt (Figure 7.8). This grain belt covers a larger area than the current wheat belt and spanned modern systems? Use the Production systems worksheet across Australia. to compare.  168 AG TECH FOCUS 9780170443111 Aboriginal Australians used fire as a management tool, burning in autumn to early winter, just as the millet seed was sprouting, because the smoke encouraged the Aboriginal germination of the native millet. grain belt Perennial native grasses such as native millet can be used to stabilise areas and act as weed and disease breaks when used in rotation with wheat. Aboriginal grain growers were See how farmers are known as Panera and sowed seed by encouraging pasture growth by using fire as a management tool hand casting. The crop was planted Contemporary for perennial native grasses. over large areas to insure against grain belt adverse seasons. At maturity, the grain was harvested by pulling or stripping Figure 7.8 The Aboriginal grain belt compared to the heads with stone knives. It was present-day wheat-growing areas then dried and stored in skin bags or Bruce Pascoe milled by mortar and pestle to make flour for bread. LET’S DISCUSS 1 What are the benefits of growing a perennial grain crop as opposed to an annual grain crop? 2 If a grain crop such as native millet can be grown over a wider range of environmental conditions, as indicated by the Aboriginal grain belt, what would be the implications of an increase in grain production areas, both locally and globally? AG IN FOCUS Alamy Stock Photo/Susanna Bennett THE WORLD’S FIRST BREAD Identify Aboriginal Australian communities are fostering the use of native grass species in modern baking. Understand Native millet can be milled to create a nutritious flour for breadmaking, as was once used by Aboriginal communities before colonisation. With increasing demand for natural products and ingredients, bread made from native millet would satisfy a growing consumer market. The Figure 7.9 Grinding stones used by environmental implications of this would Aboriginal Australians to grind the seed of be significant due to the nature of the species native millet to make bread > 9780170443111 CHAPTER 7 – WHEAT 169 > CHAPTER 7 used. Native millet is a perennial species that, once established, requires minimal cultivation and no additional fertilisers or pesticides. Perennial species improve soil structure and tend to establish vigorous deep root systems that draw nutrients and water to the upper levels of soil. The establishment of commercial production of native millet could have huge benefits for the sustainability of the local environment. Discussion 1 What are some management issues that could be encountered when growing a perennial crop? 2 What are the risks involved in establishing a new product for consumers? 3 Find out more information regarding bush tucker foods. How large is the market for native ingredients? 4 Select an Aboriginal food ingredient to investigate. How is the ingredient used? 5 Design a value-added product based on native millet as an Aboriginal food ingredient to market to consumers. ANNUAL VS PERENNIAL GRAIN CROPS PURPOSE METHOD To compare the management of an 1 Fill all the pots with soil or potting introduced annual crop vs a native mix to the top of the pot and level perennial grain crop with a ruler. 2 Sow two to three seeds per pot at LET’S ENGAGE MATERIALS a depth of 10 mm (you will thin out Large pots – you can grow as many seedlings after germination to ensure plants as you like; five to ten plants only one plant per pot remains). If of each species are recommended. If sowing in rows, sprinkle the seeds space allows, you may choose to grow evenly into the rows. each species in rows in your garden plot. 3 Water the pots with a watering can Soil/all-purpose potting mix until the soil is wet but do not flood Ruler the pot. If sowing into the ground, Winter wheat seeds and native millet ensure the water does not pool at the Native Seeds seeds. Seeds can be purchased surface. from a number of websites found on 4 Place the pots in a sunny position and NelsonNet. monitor every couple of days. Watering can 5 When all seeds have germinated and All-purpose granular fertiliser, such reached 10–15 cm in height, thin the Richmond Driver Seeds as Osmocote seedlings until only one plant per pot Camera remains. 6 Monitor the plants, growth and take RISK ASSESSMENT photographs every two to three days, or daily if you prefer. You may Seed World Using the template found on even set up a time-lapse camera NelsonNet, complete a risk to monitor the plants, growth and assessment based on the following development. Day 0 will be the day hazards: you sowed the seeds. Ideally you potting mix should grow the plants for the length fertiliser of each species growing season. slips, trips and falls 7 When the wheat plants are at the tillering stage, an all-purpose Risk assessment template Identify any additional hazards in fertiliser can be applied to support your area and make sure you list growth. This is not needed for the them in your risk assessment. native millet. >  170 AG TECH FOCUS 9780170443111 > DISCUSSION 4 Winter wheats are grazed during the 1 Compare the vegetative stages winter months, while native millet of both crops and describe can provide feed for livestock into any differences in their the dry season. Design a calendar growth stages. of operations that maximises the 2 How did your management grazing potential of both species in techniques differ for each crop? a mixed farming enterprise while 3 What are the advantages of a producing effective yields for both perennial crop in a mixed farming species. The calendar should show enterprise? a two-year cycle. LET’S REVIEW LOOKING BACK 1 Identify two factors that influence the flowering of wheat. 2 Identify and describe two production systems used to grow wheat. 3 Contrast the location of the Aboriginal grain belt and the contemporary wheat belt in Figure 7.8. FOR YOU TO DO 1 Compare and contrast the different wheat production systems in terms of management, environmental issues and productivity. 2 Compare and contrast the modern wheat production systems with the Aboriginal grain production system. 3 Construct a flowchart demonstrating the steps in native millet production by the Panera. TAKING IT FURTHER 1 Create a calendar of operations for an enterprise that crops wheat and canola while also grazing sheep. 2 Farmers must select appropriate varieties for their environmental conditions and market requirements. Research different wheat varieties and select three that would be suited to your location. Justify the reasons for the selection in terms of purpose and suitability. 7.4 Management DS Environmental management Data scenario Homework To grow a high-yielding wheat crop, the environment must be appropriately managed to ensure Wheat production can be delayed due to high that conditions are ideal for germination, growth and harvest of the wheat. temperatures and dry conditions during autumn and winter. Investigate the effect Climate and distribution of heat stress on wheat grain Wheat can be grown in a range of different climates, but the main wheat growing areas of yields with the NelsonNet data scenario. Australia occur in what is known as the Australian wheat belt. 9780170443111 CHAPTER 7 – WHEAT 171 CHAPTER 7 Bulk wheat export terminals Australian premium white wheat area Predominantly Australian premium white and hard wheat area Predominantly hard wheat area Figure 7.10 The Australian wheat belt Wheat growing areas are expanding due to the availability of new varieties, including dual- variety plants that have purpose varieties that are suited to high-rainfall environments. These dual-purpose varieties can different genetics but are still the same species be used in mixed farming enterprises and where wheat is used as a rotation crop. Soil Wheat is adapted to a wide range of soil types and grows best on well-drained soils because it does not tolerate waterlogged conditions. Waterlogging causes reduced root growth and can encourage waterlogging a condition root diseases. However, crop growth and development rely heavily on adequate soil moisture and it is where the soil is saturated with water, depriving plant vital that there is adequate soil moisture at all growth stages of the plant. Soil moisture directly affects roots of oxygen germination by influencing the speed of germination. Enterprise management WS Variety selection Homework Before planting, it is important High-yielding wheat production is largely dependent on selecting the most appropriate wheat to measure your soil water- varieties for specific locations.Varieties must be selected to ensure that flowering does not holding capacity to ensure optimum plant growth. Test occur at times when frost is likely, leading to major crop losses. Temperature is also key when your soil water-holding capacity with the practical worksheet selecting a variety because it directly affects the length of the coleoptile – too cold or too warm on NelsonNet. temperatures tend to shorten coleoptile length, affecting seedling establishment.Varieties are generally selected for: WS local environment – must be adapted to local conditions grain quality – determined by target market, for example, wheat for bread as opposed to Homework Find wheat varieties for different feed wheat locations around Australia disease resistance with the Wheat variety selection worksheet on NelsonNet. sowing time – must be appropriate for region resistance to lodging and shattering lodging when crops bend low in the stem, causing the tolerance to soil acidity plant to fall to the ground frost tolerance shattering when wheat performance in low moisture conditions. seeds are easily detached Drones are a valuable tool for use in cropping enterprises. Drones are used in wheat and fall out of the wheat head breeding programs to gather field data to enable more accurate variety selection. Drones have sensors that can detect temperature, light, moisture and other weather and climate information, and can sense other information about the physical characteristics of the wheat. 172 AG TECH FOCUS 9780170443111 Drones are being used more extensively by Shutterstock.com/Artie Medvedev farmers to monitor and manage their crops. Drones can be used to detect pest or disease infestations before they become a problem and can be used for spot spraying to deal with issues before they affect a significant portion of the crop. Drones can also be used to: detect areas where there are water shortages monitor grain development for ideal Figure 7.11 Drones can monitor wheat crops harvest timing to determine ideal conditions for harvesting. monitor weed growth as wheat seedlings are establishing detect areas of soil nutrient deficiencies. Remote sensing technology such as drones greatly decrease labour and save a farmer valuable time, money and resources. INDUSTRY IN FOCUS WHEAT BREEDER Identify Farmers must select the most appropriate wheat varieties to suit their farms and their needs, as well as fulfilling consumer and market requirements. Wheat and other plant breeders are the scientists behind these plant varieties. They have backgrounds in chemistry, biology, agriculture, genetics and technology. Plant breeders use their skills and knowledge to: evaluate breeds to suit farmers needs improve the quality and performance of crops develop varieties to meet market requirements and consumer demands. Wheat breeders work with farmers to develop breeds that are resistant to pests and disease, and tolerant of environmental issues such as heat, drought and waterlogging. They delve into the genetic pool to discover the genes responsible for taste and workability, particularly when it comes to wheats that are used to make bread and noodles. There are career opportunities for plant breeders in government organisations such as the CSIRO and universities. The University of Sydney is home to the Plant Breeding Institute, which supports a vast range of breeding programs from crops to nursery plants. There are also private companies, such as Australian Grain Technologies, that work towards the same goal of providing farmers with the most suitable crop for their needs. Discussion Grain Central 1 Identify three to five skills and attributes required to be a wheat breeder. 2 Identify three problems faced by wheat growers. List three characteristics of wheat that could be developed to solve some of these problems. 3 Research the career pathway to become a wheat breeder. How does an interest in agriculture assist in Figure 7.12 World-renowned wheat breeder, determining a pathway to this career? Richard Trethowan with his wheat plants 9780170443111 CHAPTER 7 – WHEAT 173 Sowing CHAPTER 7 Wheat is generally sown from April until mid-July, depending on the variety. Early sowing can accelerate the establishment of the plant, with a larger root system better able to cope with low moisture conditions. However, early sowing can also increase the plant’s susceptibility to some diseases. Crops that are sown too early are also at risk of frost damage as they tend to flower late in winter. Late sowing is not generally recommended because it can increase the occurrence and severity of disease. Late sowing of crops can also prevent the crop from reaching its potential yield as hot and dry conditions when flowering and grain filling occur can be stressful for the DS plant. Seeds can be direct drilled, but disc seeding can provide more effective seed to soil contact, Data scenario Homework Investigate the effect of using depending on the soil type. fertiliser on wheat yields with the data scenario on NelsonNet. DOES SOWING DENSITY AFFECT WHEAT GROWTH? PURPOSE To observe the effects of planting density on wheat seedling growth LET’S EXPERIMENT HYPOTHESIS What effect do you think sowing density will have on the growth of wheat? Write a suitable hypothesis for this experiment. RISK ASSESSMENT Using the template found on NelsonNet, complete a risk assessment based on the hazards of potting mix and slips, trips and falls. Identify any additional hazards in your area and make sure you list them in your risk assessment. Risk assessment template MATERIALS 15 large pots (ideally 20–30 L size) Pencil All-purpose potting mix Wheat seeds Ruler Watering can METHOD 1 Fill the pots with potting mix to surface of pot and ensure that the potting mix is level with the edge of the pot. 2 Using the ruler, measure 25 mm and mark this level on the pencil. This will be your sowing depth and will ensure planting consistency. 3 Separate the pots into three groups of five pots. For each group, label each pot 1 to 5. 4 Sow each pot with the number of seeds as indicated in the table below. Ensure that all the seeds are planted to the same depth and are evenly spaced. You can measure the spacing with a ruler for accuracy. Repeat for all replicates. Once all seeds have germinated, plants can be thinned out to the number of plants required per pot. > 174 AG TECH FOCUS 9780170443111 > Pot number Seeds sown per pot No of plants per required per pot 1 3 1 2 6 3 3 10 6 4 18 12 5 24 18 5 Carefully water all of the pots and place in a warm, sunny location. You will need to rotate the pots regularly to ensure they are not kept in the same location. 6 Depending on temperature, the pots will need to be monitored daily to ensure they are kept moist. RESULTS 1 Monitor the plants for a period of 6–8 weeks and then record in a table: number of tillers plant height observations such as appearance of plant, colour of leaves, etc. 2 Calculate the mean number of tillers and height for each condition (plant density). 3 Using the tabulated results, construct a graph of the following: number of tillers vs plant density plant height vs plant density. DISCUSSION 1 Interpret your results. Was there a relationship between planting density and number of tillers or height? 2 Predict what would happen if the experiment was conducted over a longer period of time. 3 What are the implications of a low sowing density versus a high sowing density on a plants ability to compete with weeds? 4 Design another experiment to test the effects of plant density on growth. Consider any improvements or additions that could be made to the experiment to make it more valid. CONCLUSION From the results you obtained, was your hypothesis correct, incorrect or partially correct? Weed management Weed management is vital to the health of the crop and weed control should commence before sowing. Several strategies are available to growers to manage weeds in wheat, including: clearing pastures or previous crop rotations chemical fallowing, where herbicides are applied and the area left fallow no tilling, allowing stubble to prevent weed growth. Weed management When crops are planted at an ideal density, they can have a positive effect on weed growth as a healthy and vigorous crop competes well with weeds, suppressing their growth and seed production. Harvesting Wheat is harvested from September through to December when the grain has dried to a moisture content below 20%. Wheat harvesting must be done at a specific time to ensure the crop maintains yield and quality because a delayed harvest can drastically reduce both. A late 9780170443111 CHAPTER 7 – WHEAT 175 harvest can also increase the risk of fungal disease setting into the crop and the heads becoming shot and sprung. A combine harvester harvests the crop by cutting it, separating the seeds CHAPTER 7 from the seed heads and cleaning the grain. This process has advanced further with combine harvester technology able to: record yield data, which can then be wirelessly transferred to database systems automatically adjust harvest height and levelling use satellite-based guidance and automatic steering shot and sprung when use automatic settings that can be programmed to avoid blockages grain seeds germinate monitor all aspects of the process using cameras linked to an interactive display inside within the wheat head the cabin. The future of combine harvesters lies in the ability to use sensor and satellite technology to enable autonomous harvesting at night. Records and financial management For a wheat grower to maintain financial stability and security, they must maintain the profitability of their enterprise. AG IN FOCUS MEASURING FARM PERFORMANCE WITH GROSS MARGINS Identify A wheat farmer would like to measure the effectiveness of different crop rotations on the yields of successive wheat crops. Understand The income and variable costs are listed below: Crop rotation Cereal Canola Pulse Gross income $848 $1007 $1100 Variable costs Cereal crop rotation Canola crop rotation Pulse crop rotation Sowing $58.40 $58.40 $58.40 Fertiliser $210.54 $210.54 $175.54 Herbicide $60.43 $17.06 $17.06 Fungicide $17.06 $17.06 $17.06 Contract- $56.40 $63.60 $66.00 harvesting Levies $8.65 $10.27 $11.22 Crop insurance $17.38 $20.64 $22.55 Total variable costs Discussion 1 Calculate the total variable costs. 2 Calculate the gross margin for each crop rotation using the formula below and record your results in a table similar to the one below. Gross margin = Gross income – Variable costs > 176 AG TECH FOCUS 9780170443111 > Crop rotation Cereal Canola Pulse Gross margin 3 Which crop rotation resulted in the highest gross margin? 4 How might a farmer use this information to determine future management practices? SMART APPS FOR SMART FARMERS PURPOSE DISCUSSION To design an app to assist growers 1 How will apps assist growers to to manage their crop. Smart devices work smarter not harder? and apps have revolutionised the way 2 Research apps available for growers can manage and monitor agriculture. What apps are available LET’S ENGAGE their crops. Information is conveniently for farmers to monitor their available at the swipe of a finger, at any production? place or time. 3 A software development company has heard about your app. They Thunkable MATERIALS would like to meet with you to app building application or software. discuss purchasing it. Create a Examples can be found on NelsonNet. sales presentation to help sell the app. You need to explain to the METHOD development company: Ten farming apps you 1 Define the problem or issue that the why your app is beneficial to should download app will assist you with. For example, growers climate and weather information to who would use the app? Is it for assist in planning crops. large or small enterprises or for 2 Plan your app. What will the app be a hobby farm? designed to do? What will be included how would your app benefit the Farm Table software and apps in the app? How will a grower use wider farming community? Would the app? it assist with sustainability? Would 3 Collect information. Research the it create employment? problem and gather data and pictures. Present your sales pitch to the class. 4 Map out features of your app and how Have members of the class judge each you would like the app to operate. For one and vote for their favourite. example, is it an interactive app? Will it be used for identification, planning or storing data? NVT online apps 5 Build your app. Ensure you get feedback as to how your app operates. You could test and rate other students’ apps within your class. LET’S REVIEW LOOKING BACK 1 When it the most appropriate time to apply fertiliser? 2 Explain why sowing time is critical to management of a wheat crop. 3 Describe three factors to be considered when choosing a wheat variety. > 9780170443111 CHAPTER 7 – WHEAT 177 > 4 Explain why the Australian wheat belt is a suitable area for growing wheat. 5 Identify three uses of drones in wheat production. How do drones assist farmers to CHAPTER 7 manage their wheat crop? FOR YOU TO DO 1 Find out how a farmer can manage acidic soils. What can be done prior to sowing wheat? 2 Identify the machinery required to manage a wheat crop from sowing to harvest. 3 Research the regulations involving the use of drones. What limitations exist for a farmer wishing to use a drone on their property? TAKING IT FURTHER 1 Identify a weed that affects wheat production and design an integrated approach to controlling the weed. 2 Research apps available to farmers to assist them manage their wheat crop. Download one and try it out. How easy and effective is it to use? Write a review of the app. 3 Discuss the implications of the use of an automated combine harvester to operate at night. 7.5 Pests and diseases Pests Cutworms attack at the vegetative stage of growth. © State of Western Australia (Department of Primary Industries and Regional Development, WA) Larvae damage wheat seedlings by eating young leaves. Adult cutworms chew plants at ground level and cause the plant to lodge. Control is achieved through spot spraying with pesticide while ensuring that the natural enemies of cutworms, such as ground beetles, tachinid flies, braconid wasps, are not affected. Cutworms thrive in weeds, so controlling weeds a few weeks before sowing wheat can prevent an attack. Figure 7.13 Cutworms damage wheat plants WS Armyworms are the caterpillar stage of certain in the leafy stage. moths. They feed on leaves, destroying seedlings Homework Alamy Stock Photo/Nigel Cattlin and damaging the leaves of older plants, just Research IPM strategies to help control wheat pests with before the grain ripens and matures. Their natural the Management of wheat pests enemies include parasitic flies and wasps, and they worksheet. are susceptible to fungal diseases. They can be sprayed in spring when they are at their greatest risk to the crop. Helicoverpa moths feed on the exposed tops of developing grains.They have a strong resistance to insecticides, so care must be taken to ensure insecticides are rotated and natural enemies such as predatory bugs, beetles and parasitoid insects are protected and encouraged. Helicoverpa can also be controlled by a viral pathogen and a bacterial toxin Figure 7.14 Barley yellow dwarf virus- (Bt), whose genes have been used in resistant plants. affected wheat. 178 AG TECH FOCUS 9780170443111 Aphids and mites pierce and suck on leaves and are also vectors for diseases such as barley yellow dwarf virus (BYDV). These are controlled by foliar insecticides and planting resistant varieties. Diseases Most of the diseases that affect wheat are fungal diseases. They present as coloured spores or a powdery coating and can affect leaves, roots or the grain heads.The main diseases that affect wheat are: crown rot – the most damaging of all the diseases. It survives in wheat stubble from one season to the next. rusts – the different types are stripe rust, stem rust and leaf rust. Rust spores can only survive on living green tissues of the plant. bunts and smuts – affect wheat heads and prevent grain development viruses – include wheat streak mosaic virus and BYDV. These diseases are transmitted by aphids and mites, so controlling those can prevent infection. Shutterstock.com/Damian Herde Shutterstock.com/Damian Herde Figure 7.15 a) Wheat smut b) Wheat leaf rust Diseases in wheat can be minimised and controlled by: applying seed treatments before sowing growing resistant varieties managing stubble where disease can lay dormant foliar sprays and insecticides to control diseases vectors crop rotations to allow for disease breaks managing weeds that may harbor disease. LET’S REVIEW LOOKING BACK 1 How can pest damage be minimised in a wheat crop? 2 Explain why it is important that a broad-spectrum insecticide is not used on a wheat crop. 3 Describe one pest and one disease that attack wheat crops. FOR YOU TO DO 1 Draw a diagram of a wheat plant. Indicate on the diagram where pests are likely to attack and identify the pest. > 9780170443111 CHAPTER 7 – WHEAT 179 > 2 Identify situations and conditions that encourage disease outbreaks. What management strategies can a farmer put in place to minimise disease outbreaks? CHAPTER 7 3 Design a leaflet for wheat farmers detailing how to spot, prevent and control one type of pest. TAKING IT FURTHER 1 Design an integrated disease management plan for controlling rust in wheat. 2 Pests can also attack grains after harvest. Identify the pests that affect grains in storage and explain how they can be managed to prevent grain losses. 7.6 Social and ethical issues Commercial agricultural practices are often placed under the scrutiny of the wider community. Because wheat is the main staple of the diet around the globe, major wheat exporting countries such as Australia are becoming increasingly responsible for feeding the world. There are many issues that growers must be attuned to, including: changing consumer trends with consumers moving away from traditional wheat varieties towards ancient grains and gluten-free products increasing demand for organic, chemical-free wheat commercially driven food products resulting in less profits and bargaining power for farmers. LET’S DISCUSS 1 Growing organic wheat necessitates the use of increased cropping land to cover losses from the inability to use chemicals to control pests and disease. What are the social impacts of this on the broader farming community? Farmers must continue to grow and supply a global market while mitigating the pressures of the increased costs of mechanisation, fuel, fertilisers and pesticides. They must also consider the impact of an increase in cropping area on land and water resources. Soil degradation and fertility issues should also be managed in addition to the effects of the loss of biodiversity. 180 AG TECH FOCUS 9780170443111 WILL THE FUTURE OF WHEAT LIE IN ITS HISTORY? PURPOSE 3 Research ancient grains and Are ancient grains a more nutritious their uses. Look at their uses and option to modern wheat? Current establish whether they would be a nutrition guidelines recommend that good substitute for modern wheat in LET’S ENGAGE people consume four to six serves of products. grain foods per day, but only two-thirds of 4 Select one ancient grain and this is being consumed as wholegrains. research its nutritional value. Consumers are becoming increasingly How does this compare with aware of their health and are preferring traditional white wheat grain. Use this information to create products that contain natural ingredients. an advertisement to promote an Ancient grains such as einkorn, spelt ancient grain to consumers. and khorasan are varieties of wheat that are the precursors of modern wheat DISCUSSION species. These varieties are becoming 1 What limitations are there on the popular with consumers due to their use of ancient grains in modern increased fibre and nutrition compared food products? with modern wheat species. They can 2 If a product becomes desirable to easily provide wholegrains to the diet. consumers, then farmers will grow These varieties each carry their own set it to meet demand. Evaluate the of genes that can be used to increase process of: the gene pool of current wheat species, a a farmer diversifying and growing encouraging the development of species an additional crop that are high yielding, high quality and b a farmer changing production to a with the benefit of increased nutrition. completely different crop. Take on the challenge of researching and 3 Conduct a cost–benefit analysis of promoting ancient grains by first gainingone of the processes indicated in an insight into consumer preferences by Question 2. conducting market research. 4 Research the markets available for ancient grains? Are they MATERIALS sustainable? Computer or smart device with access 5 It is recommended that people to internet increase the amount of wholegrains METHOD in their diet, but it can be a struggle 1 Design a survey to establish for parents to replace white current consumer preferences to bread, a favourite of children, with Wonder White Bread commercial grain products. Find out how much whole grain varieties. Wonder consumers value: White bread is promoted as ‘high- fibre bread in disguise’. View nutrition the television commercial and health analyse the promotional campaign value for money for this product. Would this type convenience. of campaign work for a product 2 Survey as many people as you made with ancient grains? Why or can. Collate the information why not? to determine what consumer preferences in your community are. 9780170443111 CHAPTER 7 – WHEAT 181 LET’S REVIEW CHAPTER 7 LOOKING BACK 1 Identify two consumer trends affecting wheat production in Australia. 2 Outline some of the impacts of wheat farming on the Australian environment. 3 Explain why wheat farmers are facing increased costs whilst trying to feed a growing population. FOR YOU TO DO 1 Could Australia change to completely organic wheat production? Make a list of pros and cons and discuss the issue with your class. 2 Approximately 70% of Australian wheat is exported and the price farmers receive can vary widely. How would unpredictable wheat prices affect Australian farmers and rural communities? TAKING IT FURTHER 1 Investigate which alternative grains are available at your local supermarket. a Compare the price of these grains and flour to wheat products. b Determine the country of origin of each grain. c Research the history and significance of one of these grains to the society from which it first came. 7.7 Sustainability Sustainable methods and practices Traditional wheat cropping practices have heavily reduced the amount of soil organic matter over time. This has resulted in declining soil fertility and reduced water use efficiency. These can be alleviated by increasing inputs of organic matter through the application of manures and recycled organic matter and by implementing the following practices. 1 Crop rotations – it is not ideal to plant wheat crops successively. Growing a different crop in between wheat seasons provides disease and weed breaks. Legume crops and pastures can be used in rotation with wheat as they can provide valuable nitrogen in the soil. This practice is called ley farming. Other rotation crops such as canola can be an effective disease break because their taproots help to loosen the soil. These rotations result in reduced pesticide, herbicide and fertiliser applications and the costs associated with these. Wheat Wheat Wheat Pasture Pasture Pasture Pasture Pasture Wheat Wheat Wheat 1 2 3 4 5 6 7 8 9 10 11 Growing season Figure 7.16 Pasture ley farming for improved wheat production 182 AG TECH FOCUS 9780170443111 2 Conservation tillage – this method involves sowing wheat into the residue of the previous crop. This means little or no cultivation is employed, resulting in less compaction and increased moisture retention, which are ideal for wheat growth. Stubble left from the previous crop can stabilise the soil and has the benefit of adding humus to the soil, providing the crop with additional nutrients. AG IN FOCUS COULD SEWERAGE BE THE SOLUTION TO SOIL SUSTAINABILITY? Identify Agriash is a by-product of the sewage treatment process that improves the soil. Understand Agriash is a product made from treated solid sewerage waste. It is heat-treated to over 650 °C and is completely sterile. It is used as a soil conditioner, fertiliser and soil acidity neutraliser. It is an excellent source of phosphorus and ideal for use on acidic soils. Anecdotal evidence from farmers using Agriash found it to be more effective at encouraging native pasture growth through successive seasons, indicating that it could be highly effective in a pasture rotation with wheat. It is currently being produced in the Australian Capital Territory and should become increasingly sought after as a highly sustainable source of agricultural fertiliser. Discussion 1 Many developing countries use human waste as fertiliser but there are health issues associated with this. How does Agriash differ? 2 What are the benefits of using a recycled waste product for commercial crop production? 3 Create a flow diagram for a) commercial phosphorus fertiliser production and b) Agriash Agriash production. Compare each process and find out which has the biggest impact on the carbon footprint of commercial wheat production. Sustainable technology Geographical information systems Geographical information systems (GIS) can be used by farms to collect data and link it to specific geographical locations using global positioning system (GPS) technology. It is a way of giving context to data. For example, GIS can analyse soil data from individual paddocks and map it against farming practices to help farmers make informed decisions regarding crop selection and management practices. Farmers can use seasonal information to determine long- term strategies for their farm by estimating future crop yields and pinpointing problem areas such as susceptibility to soil erosion. The use of such technologies can reduce costs and increase production, all while maintaining the integrity of the environment. GIS and GPS technologies can also be integrated with traditional farming practices and machinery through tramline farming. GIS systems can be used to develop a tramline farming system that creates permanent wheel tracks, minimising soil compaction areas. 9780170443111 CHAPTER 7 – WHEAT 183 Sustainable decision-making CHAPTER 7 Sustainable practices and technology have a number of benefits. In the short term, costs can be reduced and farmer incomes stabilised. Maintaining the integrity of the environment and reducing land degradation results in long-term security for a farmer through increased yields. The development of sustainable wheat varieties can have a global impact: genes transcend boundaries and a variety adapted to a specific climate can be used throughout the globe where similar climates and stressors exist. AG IN FOCUS DECLINING WHEAT YIELDS DUE TO CLIMATE CHANGE Identify Rising temperatures and lower rainfall are predicted to significantly reduce wheat yields. Understand Climate change has resulted in lower annual rainfall and increasing temperatures across the country. This has affected the management and production of wheat crops, not only in Australia but worldwide. In recent years, exceptionally warm and dry conditions during autumn and winter have adversely affected production by delaying the start of the growing season, accelerating development times and reducing the flowering period of the wheat. Short-term effects will initially be seen in the livestock feed market with a predicted rise in grain prices eventually affecting meat prices. Further predictions of climate variability and extreme weather events could further affect wheat and other crop production resulting in uncertainty when it comes to global food security. Discussion 1 In terms of the wheat production cycle, what would be the effect of the following weather events: a unseasonal rain at harvest time b a sudden increase in temperature followed by a sudden decrease in temperature c warm and wet conditions during winter. 2 How can farmers alter their management practices to safeguard against the effects of climate change on their wheat production? 3 How important is agricultural research in terms of maintaining global food security? 4 Design an experiment to test the effect of different temperatures on the growth of wheat plants. You could obtain seeds of different wheat varieties to see if their germination and growth is affected by temperature. 5 Using the link found on NelsonNet, research different wheat varieties and their growing seasons. Create a resource that maps out which varieties would be best suited for a specific location to be used by farmers determining which variety Plant breeders to plant. pre-empt climate effects 184 AG TECH FOCUS 9780170443111 LET’S REVIEW LOOKING BACK 1 How have traditional farming practices affected the quality of the soil? 2 Outline the farming practices that can improve a wheat farm’s sustainability. 3 How does ley farming improve nutrient availability in the soil? 4 What sustainable technology is available to farmers to help them in their decision making? FOR YOU TO DO 1 Research conservation tillage and conventional tillage methods used by wheat growers. Compare the two methods and list the advantages and disadvantages of each method. 2 Explain how the use of GIS and GPS technologies can improve the sustainability of a soil. 3 Compare the effects of short-term sustainable practices to the long-term effects of sustainable technology. TAKING IT FURTHER 1 Perennial grains such as native millet can improve the sustainability of an area. Research the production cycle of native millet and provide a case for the breeding of perennial wheat. 2 Evaluate the use of conservation tillage in a wheat production system with regard to environmental sustainability. 7.8 Marketing The market Approximately 70% of wheat grown in Australia is exported overseas, mainly to the Middle East and Asia. Australia accounts for a relatively small proportion of the export market at just under 12%, while European countries are responsible for over half of the international wheat export market. Wheat grown in Western Australia is a high-quality milling grain that is produced specifically for export, while 40% of wheat grown in the eastern states is for local consumers and livestock feed. Export customer On-farm Grain storage Port terminal planting receival grain quality harvesting grain declaration testing storage quality testing planting seed retention storage and fumigation Seed supplier/retailer Livestock certified seed only Milling feed customer Figure 7.16 The marketing chain of wheat 9780170443111 CHAPTER 7 – WHEAT 185 Consumer trends CHAPTER 7 While pasta and noodles have been a staple food in many countries, noodles are set to overtake the market with the increasing popularity of instant noodles. In an age where the workforce is rapidly increasing and populations have restricted time and resources, people are turning towards convenient food options. Owing to the variety, versatility and ease of preparation of instant noodles, the market is expected to dramatically increase. Another increasing trend is the shift to gluten-free products with a rise in the diagnosis of coeliac and other auto-immune diseases in developed countries. LET’S DISCUSS 1 How will an increase in gluten-free diets affect the Australian wheat industry? DID Over 100 billion servings of instant noodles made from wheat are consumed YOU each year globally. KNOW AG IN FOCUS TURNING OFF GENES CAN MAKE WHEAT EASIER TO DIGEST Identify With the discovery of the wheat genome sequence, genes that relate to coeliac disease, gluten intolerance and allergies can be isolated and potentially deactivated. Understand Scientists have discovered and mapped the genetic code in wheat. This means that genes for individual traits can be mapped, specifically identifying genes for traits such as disease resistance and frost tolerance. Going beyond yield improvement, genes can be traced to individual characteristics such as digestibility. This would potentially allow genes to be regulated, or turned on or off. The development of a wheat variety that could overcome health issues such as coeliac disease would expand the market for wheat and increase demand for wheat products worldwide. Read more about how Discussion scientists managed to crack the genetic code of wheat. 1 How would the knowledge of a complete gene sequence for wheat speed up the development of new varieties? 2 If the demand for wheat rapidly grew in a short amount of time, what would be the implications for global wheat production? 3 Public perception of genetically modified crops is often negative. Conduct a debate to argue whether genetic manipulation of wheat is justified if it benefits the health of the wider community.  186 AG TECH FOCUS 9780170443111 Market specifications Wheat quality is determined by its protein content. Protein content then determines the end use of the wheat. The price received for wheat depends on its market classification. Wheat is classified using the following criteria. Australian Prime Hard (minimum 13% protein) is the top-quality milling wheat. It is used WS to make high-protein, high-volume breads. It is also used for the production of superior Homework quality Chinese-style yellow noodles and Japanese ramen. Identify which products Australian Durum (minimum 13% protein) produces coarse semolina rather than flour when require which specifications with the Wheat market it is milled, and thus is ideal for making pasta. specifications worksheet. Australian Hard (minimum 11.5% protein) is used to produced white bread products including flat breads, pan breads and steamed breads. Australian Premium White (minimum 10.5% protein) is used to make a wide range of products including Hokkien-style noodles and flat breads. Australian Standard White has no minimum protein content. It is a versatile medium- to low-protein wheat used for general baked goods such as biscuits and cakes. Feed Wheats have the lowest protein levels and are not suitable for milling. Marketing strategies Wheat growers can store grain on their farms and then sell the grain directly to flour mills and livestock feed wholesalers. Farmers can also sell their grain through grain trading companies or by contract with organisations such as the Australian Wheat Board. The majority of Australia’s wheat production is exported overseas to Asia and the Middle East. Wheat prices are determined by the overseas market and is dependent on the quality of the wheat. Wheat prices can rise in response to seasonal conditions that cause a reduction in global production, resulting in Australian wheat being sold for a higher price. AG IN FOCUS VALUE-ADDED WHEAT THAT GOES BEYOND THE BREAD-AND-BUTTER PLATE Identify A flour milling plant in Nowra makes gluten, starch and alcohol from wheat for a multitude of uses. Understand While the majority of wheat produced goes to produce flour for baked goods, a flour mill on the south coast of New South Wales produces gluten and starch that is used to make a variety of products such as furniture glue, hand sanitiser and confectionery. With over 6000 wheat growers supplying the factory with wheat, it is the world’s biggest starch plant. Because wheat is classified for market according to its protein content, which can be determined by growing conditions, the factory provides a use for wheat that has been adversely affected by unexpected climatic conditions, giving growers the opportunity to sell damaged wheat at a premium price. The factory also recycles its water for irrigation and utilises carbon dioxide produced in another factory that produces carbonated drinks, further adding to the sustainability of the enterprise. > 9780170443111 CHAPTER 7 – WHEAT 187 > CHAPTER 7 Discussion 1 Research other ways in which wheat can be value added and identify three different products. 2 What are the benefits of value-added products for: a the farmer b the manufacturer c the consumer. 3 Design a marketing campaign for a value-added wheat product. You should use two different forms of advertising in your campaign (review Chapter 4 to assist you). LET’S REVIEW LOOKI