TAS

Crop production

Uncover the innovations transforming protected cropping systems, from new technologies to sustainable solutions for vegetable production.

This collection of resources explores the advancements in protected cropping, including automated control systems, nutrient management, and integrated pest management. Teachers can integrate these resources into lessons on horticulture and agricultural sustainability, offering students a comprehensive view of the latest techniques shaping modern farming practices.

The NVP (National Vegetable Protected) Cropping Centre

Watch The NVP Cropping Centre (6:05)

Dist. Prof. David Tissue describes the NVP Cropping Centre

Distinguished Professor David Tissue

Western Sydney University

Well, this is our new glasshouse, it’s about a year old, it forms the basis for the National Vegetable Protected Cropping Centre. It was funded by Hort Innovation and also by Western Sydney University. And the objective is to have cutting edge research on horticultural products in response to a suite of environmental variables. So, we’re now in the second phase of our research program trying to locate the impact of variable light quality on crop production.

So, the facility is composed of nine different rooms. One of the rooms is a teaching and demonstration bay, that’s the large room over here. In that bay we are teaching our students and industry folks how to manage crops including the environmental variables for maximum crop production. We’re interested in pollination as well in that room. And then we have eight research bays and those are fairly unique to Australia. So, each of these bays is 105 metres squared, there’s really fine control of CO2 atmosphere, fine control of temperature and humidity.

And we’re also able to deliver the nutrients and water directly to each plant which makes it very water use efficient and nutrient use efficient. So, the research purpose in this glasshouse is to really look at what are the key variables that control vegetable production.

So, for instance a lot of growers have been doing things the same way for a very long time because it’s been relatively successful. But the advantage of a research glasshouse is that we can try some new things that they may not be willing to do in a production setting to see if we can get increased productivity.

For example a lot of glasshouses don’t use elevated CO2 but we know that can increase productivity. And so what we want to be able to do is to use CO2 for example to increase productivity but not increase cost much. The same can be said for water, so agriculture takes a lot of water by delivering the water to the crop right to each plant we’re able to reduce water use and nutrient use as well.

So, why do we do research? Well, we do research because we’re really trying to figure out how to improve the industry in terms of the quality of the product that we produce but also the amount that we produce. And that’s why this is such an excellent facility for that and why Hort Innovation which is the research body for the horticultural industry in Australia have invested in this facility. We should be able to provide them with new ways of growing their crops and ultimately what we’re trying to do is to save water, save nutrients and decrease energy use. That’s the objective of this particular glasshouse.

So, the funding for the facility has come from Western Sydney University and also for Hort Innovation. Now, Hort Innovation is a research corporation that has levies on growers of many different horticultural products. I think over a hundred crops are levied which means that a grower provides some money to Hort Innovation and then asks them to invest wisely in terms of research. And so that research can span a wide variety of topics, it might not be specific to say eggplant or lettuce but to the industry in general although we can target specific crops as required.

For instance Hort Innovation has invested funding for pollination biology and we’re trying to look at non-mechanical means of pollination which is very labour intensive. So, stingless bees are an opportunity for us to use a natural pollinator in this glasshouse environment.

We’re also looking at things like Smart Glass which is a film that we’ve put on this glasshouse to reduce the amount of heat load inside the glasshouse which is also a very major component of Hort Innovation’s research objective which is to reduce the running costs of the facility while maintaining the quality and the quantity of the product that’s produced.

The role of research is to try and determine how to produce a better crop and so you have two basic directions, one is developed by the industry, they have particular short term and occasionally medium term goals. The second one is through the universities and the universities are able to take thirty or forty years of information on looking at the environmental effects on any plant production and then we can apply that knowledge to crops like eggplant or capsicum and so on.

So, research actually has a lot of different avenues and we try and explore ones that are going to be best for the industry but we’re also interested as scientists in some of the blue sky research. That is really drilling down and trying to understand what some of the drivers are of plant response which are beneficial to industry but they may not know it until a bit later.

[End transcript}

Crop production in an intensive system

Watch Crop production in an intensive system (8:15)

Nicky Mann describes crop production in an intensive system

Nicky Mann

Protected Cropping Australia, PCA

So, protected cropping is anything that is protecting any type of crop or cultivation, so it can be any type of structure or mechanism being netting whether it’s plastic or glass or some sort of material that actually covers a crop and protects it from the climate or the elements.

So, in protected cropping at the moment there is a lot of people ranging from just pure netting and that is to protect the crops from hail or birds or insects etcetera. That’s probably the most basic and the most extensive type of protected cropping for most fruit trees and extensive crops.

The next sort of like stage up there in protected cropping is plastic and they can range from all types of shapes and sizes from tunnels to multi stand greenhouses to absolutely beautiful, big structures using plastic, sometimes it’s only got one skin of plastic, sometimes it’s got two skins of plastic what they call twin skin where they pump air between the two skins to help modify the atmosphere within the glasshouse or the plastic house and then you’ve got the glasshouses.

And they can be quite basic structures, quite low to very, very high structures up to 8 to 11 metres is the tallest glasshouse in the world. And these are made from various types of glass from just plain normal glass to diffuse glass.

So, protected cropping is anything that has a structure over a crop to maximise a yield or to protect it from the climate or the elements. In a facility such as this at the Western Sydney Uni it’s amazing how you can actually grow excellent crops that are you know flawless with you know no disease infections, no insect infections and stuff like that. The reason they can do that is because they obviously have got a controlled environment here so they can actually keep off the rain of the crops. They can also you know make sure that they don’t get blown over by wind.

In this facility here they are growing capsicums and they are doing a very good job of it. They’re growing in a substrate called grow wall which is made out of volcanic rock actually expanded at high temperatures. And it’s basically an artificial soil medium or base to grow the roots of the plant in and it’s very, very good substrate for doing that purpose of what it does is actually holds the roots off the plants, we then feed the plant with exactly what it wants in terms of water and fertilisers and nutrition.

And we deliver that food and nutrition to the plant through a little dripper or spike directly to the root of the plant and in this case it’s capsicums, that plant then actually takes whatever it needs, water and nutrients, puts it up its system and then procreates leaves and photosynthesises and then produces fruit, whatever the plant doesn’t need gets captured in little gutters which run below the crop and then go back into a collection system where it’s actually filtrated and either used back on the crop again or it’s actually disposed of by putting it onto lawns in the facility here.

Another thing that they’re doing here they are using strings to actually hold the plants up so that they can you know hold a lot of yield and not fall over.

As a grower in the protected cropping industry I often get asked what are the advantages and disadvantages of being a protected cropping grower? Obviously the advantages are that we can actually control the atmosphere or the climate within our greenhouse, we can optimise the conditions to optimise and maximise yield for our crops. Obviously we mitigate risks from you know rain, hail, insects and pests and birds but sometimes that can also be a disadvantage because what is actually happening is that you’re actually creating this perfect environment, it can actually be perfect for pests and diseases as well.

Big disadvantage for our industry because it’s growing so quickly and the technology is really racing ahead it’s actually we battle to find really good skilled people who’ve got the skills and experience to keep up with the technology and people who are actually prepared to do the grunt work and work day in and day out in environments that are sometimes quite hot for humans, perfect for plants. You rely so heavily on the technologies.

So, we’re feeding, we’re controlling these plants, we’re watering and feeding them all the time. So, if you have something like a power cut or electricity blackout you’re in trouble unless you have a backup generator because your plants are then at the mercy of the elements without any water or way to survive without you feeding or looking after them.

So, you know they’re big pluses but there’s sometimes disadvantages and you know it’s also keeping up your skills up to move with the times and the technology, that’s probably our hardest and biggest challenge at the moment. The technologies are changing daily, we’re finding now that people are trying to maximise production in countries with low light levels so that LEDs are coming into play. We’re finding other places that are actually limiting some of the light that they get too much light for crops like strawberries where they’re actually doing blackouts in their glasshouses. A lot of the plants used in the protected cropping industry are actually bred for this type of production in a high tech, they’re used to producing a lot of crop and I would compare it to you know training a horse for the Melbourne Cup with a thoroughbred horse that’s got good breeding it’s bred to race whereas a crop that you probably would grow outside in the soil is probably like a pony that does show jumping or dressage it’s got a different you know purpose.

These plants here have been bred there scientists have put a lot of work and effort into making sure they’re well-bred and that they are resistant to a lot of the diseases or the common diseases and that they are a little bit more resistant to pest outbreaks. So, they’re not genetically modified, most of them are selected on good genetics and the big focus now a lot of the breeders are producing really good nutrient dense food that are full of nutrients for you and I and that the fruit is also really presentable and it looks good and it presents well and it tastes good because you know everyone’s now back onto variety that have good taste.

The technology that protected cropping offers is actually something that’s going to open a lot of doors for kids or young people who’ve got great skills with maths and science and engineering skills because the way we grow with all really high tech we can see our greenhouses being modified to be better engineered. You know in our circumstance where we grow at the moment we are obviously growing in a really hot climate it would be nice to have more ventilation but at the same time we don’t want the structures to fall down.

So, engineering is going to be a huge play in the future to really improve our structures. I mean we’re all about you know the size of growing crops under controlled environments but there’s so much more that we can learn. So, the protected cropping industry in Australia is worth 1.8 billion dollars to the economy and it is the fastest growing sector in the horticultural industry and it’s going to only get bigger. And it’s actually getting bigger around the world so globally protected cropping is increasing because of the variable climates and climate change people are wanting to minimise the risks so what they plant is what they reap so that they take out the risks. So, protected cropping is growing and it’s becoming a really big sector and obviously worth a lot of money to the Australian government and to the economy here.

So, protected cropping at farm gate level is 1.8 billion. The potential of the protected cropping industry in Australia is enormous. I’m actually really excited and every enthusiastic about the potential for the young people because they’re born with iPhones, iPads, computers, they’re very familiar with technology and our industry is all about technology, it’s about using the resources to maximise yields to get crops growing out of season in you know different climates and the potential as well is for exports. And we can actually produce a product that customers in Japan are very familiar with they want out of season and we can actually produce in here in Australia and export into a gap and a market.

[End transcript}

Automated control systems – an agricultural example

Watch Automated control systems – an agricultural example (7:57)

Marcus Van Heijst describes automated control systems

Marcus Van Heijst

Priva Oceania

So, automated systems allow the crop to be grown while the grower is not present. So, the automated system is there to nurture the crop, to look after the crop 24 hours a day, 7 days a week, 365 days a year. A good grower could do it himself if he was there all the time but with an automated system the system itself will continue to do his job throughout the whole period whether he’s there or not.

So, it all started in Roman times when the Romans actually developed the first protected cropping systems. Then during the Joseon period or Joseon Dynasty I should say in the 15th Century the first actual greenhouses were developed. These actually included very simple climate control like heating and cooling but the newer developments were not until after Second World War mostly in the Netherlands where the first greenhouses were used to grow crops all year round.

These greenhouses included heating using simple heaters to start with with kerosene and later with gas heaters which also gave CO2. And then in the mid 70s the first actual controllers came on the market. These controllers were analogue controllers, analogue meaning they contained dials and they had what’s called VU metres like you might see in your old grandad’s radio. And the dials would show you the temperature and the actual knobs you would use to set your temperature etcetera.

Then in the late 70s the first actual controllers came on the market which were digital. So, these controllers actually had memory and allowed you to set settings via a keypad. The graphical user interfaces didn’t happen until the early 90s with the advent of PCs which allowed a user interface with actual graphics on it. So, the computer knows what to do via a whole host of sensors that are connected to the computer.

Now, these sensors include a weather station to measure wind speed, wind direction, rain, temperature, humidity but also include sensors inside a greenhouse which are temperature humidity sensors, hot temperature sensors, crop sensors like substrate moisture sensors, substrate temperature sensors and also sensors that are used in the water room like flow sensors, the pH of the water is measured there and EC of the water which is an indication of how much fertiliser is in the water.

So, with this information the controller can make decisions via the algorithms that are programmed into the controller. So, the climate systems that you find in a modern greenhouse include ventilation which have the vents that go up and down which provide cooling. Screens which retract and employ by the user, via the automated system to provide shading in case it gets too hot, also to provide energy reduction at night for example and blackout systems which allow the system to actually blackout a compartment to shorten the day and this is for XXXXXXXXXXXX crops.

Also, in a greenhouse you’ll find lighting of course to extend the day and also to provide energy if the Sun’s not giving enough. You’ll also find heating which is done by hot water pipes which are circulating hot water through them and controlled by pumps and valves. Air circulation fans will make sure that the environment within the greenhouse is homogenous at all times. And pad and fan systems will allow the system to introduce air from outside and cool it as it enters the greenhouse, cool the air, there by cooling the house and also raising the humidity.

More recent developments include cooling systems which use either cooled water or glycol through heat exchanges to both lower the temperature but also lower the humidity because once the air is cooled below the dew point, the water will actually drop out of the air and it allows you to control humidity in areas where the humidity is very high. So, user interfacing of the control systems, well at the end of the day the control is done by a controller and a controller works in bits and bytes and it’s just doing its job.

Now, users generally don’t understand bits and bytes and we want to make the system usable for the user so we develop a user interface. So, this will include a PC which will have generally text space settings and read outs by text but also includes graphical user interface. So, this is where there’ll be either a shot of the greenhouse or an aerial photograph over which is overlayed various settings and readings that are achieved within that greenhouse.

Other developments these days that we’ve been working on at Priva are for example the app which allows users to remotely both monitor and control their greenhouses from anywhere in the world either one site or multiple sites, so data collection. Now, from day 1 when a system is first set up data is being collected by the system. All systems that are supplied include data collection which is continuously collected from the day it’s installed. And what the users do is look at their data on a daily basis to make decisions on what they should do with settings and what they should do with the crop etcetera. Managers on the other hand will look at their data and make decisions as to when they should be harvesting, how much they might be harvesting. And on the other hand the company owners or upper management will make decisions on what crops to grow and these sort of things.

Data can be analysed in various ways and these days with the advent of Cloud systems and Priva is one of them we are looking at ways we can actually access the data and also analyse the data through the Cloud so the data can be used and analysed by the various companies that own the data.

At the end of the day what’s also important is data security and any company, us included will always ensure that the data belongs to the user or to the company that’s bought the system and cannot in anyway be accessed by any employee of Priva in anyway whatsoever.

One exciting development is the advent of robotics. So, there’s various companies working on various types of robots including Priva, we’re currently developing a robot which autonomously picks tomato leaves. Other types of robots under development are scouting robots and these robots scout by the pests or diseases autonomously and then report back to a central system so that the user and managers can see where various hotspots are within their crop and also then do targeted spraying where necessary. Other types of robots that are under development are for example picking robots. These robots will then autonomously pick the fruit and other types of robots are spraying robots, they’re already being used but they’ll get smarter and smarter as well.

Then there are Cloud developments, now everyone is probably aware of the Cloud but we’re only just at the early stages of all the possibilities in the Cloud. For starters there’s remote access to various systems, there’s also data storage in the Cloud and data analysis in the Cloud. There are alarm systems that are based in the Cloud and there’s various other services which will come online as time goes by.

Other things that are being worked on at the moment are things like the sustainable urban delta and this is a concept where greenhouses, living areas, industrial areas, commercial areas are fully integrated. And the idea behind it is there is a huge movement towards urbanisation worldwide. So, the trend is we’re going to have larger and larger cities.

For example Shanghai is a city of 27 million people. And what happens is people are all congregating in these large cities but they also need to eat of course. By combining the resources of water, energy, light, etcetera we can be much, much more efficient in terms of where we produce food and where it gets consumed.

[End transcript}

The pupose of research in agricultural production

Watch The purpose of research in agricultural production (7:20)

Chelsea Mair explains the purpose of research in agricultural production

Chelsea Mair

Western Sydney University

Agriculture is what we rely on as a species, as humans and with different climactic conditions into the future. Climate change is making rain events more unpredictable, larger rainfall events that end up just flowing into river systems and not actually being used by the crops or the plants in general. Protected cropping is the way of the future because we can control all of the climactic variables within the glasshouse. We can control how much radiation or sunlight the plants see. We can control the temperatures inside the rooms. We can control how much water they receive and how much fertilisation they receive as well.

This will really greatly benefit the world because we don’t need to spread extra fertilisers onto the plant that then run into river systems and also the production in glasshouses can be much larger than what is actually produced out on cropped land. This will also save natural space for wildlife as well as human enjoyment for the scenic value as well.

Glasshouses are being used all over the world to grow crops for human consumption. In a lot of these glasshouses are in the northern hemisphere.

However, we’re in the southern hemisphere here in Australia and one of the major issues that farmers in Australia have is the really high temperatures with growing crops outside but also inside we use an enormous amount of energy to control the conditions inside the glasshouse to give the plants optimum temperature for growing.

This is a large concern because producers of crops are always wanting to save money and moving into the future we want to be as sustainable as possible and not use more electricity than we actually need to produce the crops that we need as a community. So, the main problem that the industry of protected cropping is experiencing in Australia is that of controlling the temperature with inside a glasshouse. And this is actually where most of the cost of producing a crop inside of an already established glasshouse comes in. It’s incredibly expensive to cool as well as heat a glasshouse to make it the optimum condition for a crop to grow. It’s incredibly expensive to cool down a glasshouse in the really hot summer months that Australia experiences.

We’re addressing that question here in our protected cropping facility here in this glasshouse. We have four research rooms established at the moment, two of which are a normal industry standard glass. The other two rooms have a film that’s basically like a car window tinting that was actually developed for residences to keep them cooler during the summer months. But in our glasshouse we have them installed on the roofs and the side walls and our aim is to test whether this film will actually reduce the cost and the energy to consumption to maintain the crops at an optimum temperature and condition but also to make sure that the plants actually produce the same amount and the same quality of produce.

For scientific research and general funding can come from numerous different sources. It can come from government. It can come from the institution where the research will be conducted. It could also come from industry. In our scenario here at the glasshouse we are actually being funded by Western Sydney University as well as Hort Innovation Australia which is owned by the growers of Australia. We typically call this an industry linkage grant. I’ve been working in research for a very long time. My dad was actually a research scientist and I volunteered and worked with him when I was in high school and when I graduated college I told my college roommate that I really wanted to travel to Australia to experience the reptiles of Australia.

And after college I was working at Duke University and I talked to my boss there and told him that I really wanted to travel to Australia and he told me about Hawkesbury Institute for the Environment at Western Sydney University and got in touch with Dr David Tissue, he’s the lead scientist on this project and applied for a job working on drought impacts on native Australian trees. And I worked there for awhile, I then decided to take some time off and travel and then this project came up and I’m very passionate about growing vegetables and basically enhancing food security for our communities in the future and this was a perfect project to get involved with.

With our experiment here we’re specifically testing how Smart Glass influences the cost of producing a crop but also how it influences the crops that are growing under it. When you have a scientific research question it’s important to only test what your specific question is.

So, we have four research rooms here, two are what we call control which are the industry standard glass, no different from another glasshouse down the road and then the other two rooms have the Smart Glass film on them. All of the variables within the four rooms are the same, the temperature is the same, the CO2 concentration is the same, humidity is the same. All four rooms get the same amount of irrigation and fertilisation. So, all of the variables are exactly the same within the rooms except for the Smart Glass. So, we were actually able to tease out our results when we do our measurements and if we do find any differences between our controls and our treatment rooms we can deduce basically that the Smart film, the Smart Glass was what caused the difference.

We conduct lots of different measurements here. We have light sensors to measure exactly how the Smart film influences the light that’s coming into the glasshouse, we continuously monitor that. We also have the sensors in the control room so we can see the difference between the control and the treatment. Every week we measure how much fruit is produced in each of the rooms. Every week we count how many buds and flowers are on each of our experimental plants. We also do what we call gas exchange measurements where we clamp a chamber onto the leaf and measure really fine-tuned tiny measurements of CO2 and water vapour inside that chamber which tells us how much the plant is photosynthesising, how much CO2 it’s taking up and creating sugar with.

At the end of the experiment we’ll also weigh all of the biomass, all of the biomass that the plant has produced per room. And hopefully with all of those measurements we will be able to basically say that the Smart Glass is doing one thing or the other. We also will be doing analysis on the fruit themselves to see if there’s any differences in nutritional quality of the fruit because we don’t only want to just save on cost but we want to make sure that the fruit is actually still nutritious and of the industry standard that is expected.

[End transcript}

Nutrient solutions in protected cropping

Watch Nutrient solutions in protected cropping (5:28)

A demonstration of nutrient solutions in protected cropping

Western Sydney University

When growing food crops in a glasshouse it is essential for each plant to get its 4 basic requirements to grow. These include: light, carbon dioxide, water and nutrients. Nutrients can sometimes get overlooked but it is essential to a plant’s development and it is what helps a plant get to its later stages healthy and strong.

Take this mature capsicum for instance, it didn’t just get here from water and light alone. Various chemical nutrients give this plant that extra boost from the energy provided to the plant from light and the water that helps a plant to transpire and carry sugars and nutrients. It is the nutrients that are responsible for the plant’s metabolic processes and functions as well as its resistance to pests and disease which nutrients are needed to grow a plant and how do cropping industries carry out this task on such a large scale?

Well, it all comes back to chemistry and that good old Periodic Table. Thanks to the many researchers who have done the heavy work for you we now know that it is these chemical elements that are essential for most plants to grow well. These chemicals are of course needed but in various concentrations. Concentrations are super important to get correct in plants especially when applying on a large scale. These chemical ratios get divided into 2 categories. These are macro nutrients and micro nutrients.

As you can probably guess it is the macro nutrients that are needed in large concentrations and the micro nutrients that are needed in small concentrations. But all these elements are still essential for a plant’s growth. All these chemicals are combined in their appropriate concentrations and mixed into a solution that can be taken up readily by the plant, water being the solvent. Having the wrong ratios of nutrients or too little nutrient can damage or kill the plant or stunt its growth or cause wastage of the chemicals used. So, getting this right is an art in the agricultural industry.

When making solutions to feed plants we have to consider the quantities and concentrations of the chemicals used and this can vary depending on a plant’s stage of growth from early stages of seedling germination to the stages of vegetative growth, budding and flowering and then its mature stages of ripening. What needs to be considered is the effect that certain major nutrients have on plants such as: Nitrogen, Potassium and Phosphorus. When technicians are calculating the nutrient concentrations they must consider the pH and possible precipitation of the chemicals in solution because this can greatly effect what elements can be taken up by the plant.

So, how does our technician measure out these concentrations correctly? Why? Through the chemistry calculation using the Molarity Formula, fear not though it’s easier than you think. In the formula ‘C’ represents the concentration of a solution, ‘n’ equals the number of mols in the substance being dissolved and ‘V’ equals the volume in litres of the whole solution. To make this easier to understand here is a stock nutrient solution to grow capsicums in hydroponics. Of these nutrient types let’s look at Calcium Nitrate in the stock solution. This nutrient is added at 1.086 kg stock into a 10L total solution.

Here are the steps to find the concentration of this molecule in the solution. We will first have to use that handy Periodic Table again and find the molecular weight of each element that makes up Calcium Nitrate. Here they are. Calcium equals 40.078 grams per mol. Nitrogen equals 14.007 grams per mol. And Oxygen equals 15.999 grams per mol. Plugging these atomic weights back into the Calcium Nitrate molecule we form a calculation: 1 atom of Calcium, 2 atoms of Nitrogen and 6 atoms of oxygen. Calcium Nitrate has a molecular weight of 164.09 grams per mol. The next step is to divide the mass of nutrient chemical used by its molecular weight. In this equation the stock must be converted from 1.08 kilograms to grams. So, it is 1080 grams divided by 164.09 which equals 6.58 mols. We have now calculated the number of mols of the substrate ‘n’.

Now, remembering that previous formula of C equals n divided by V we can plug all the figures in and solve the concentration calculation. C equals n divided by V. Concentration equals the number of mols divided by Volume. C equals 6.58 divided by 10. So, the concentration is 0.7 mols per litre of Calcium Nitrate.

To do this on a larger scale like in a hydroponic tank, the concentration of all the different chemicals can then be calculated and then this stock solution can be diluted to the levels needed for plant growth. These processes of calculating the concentrations are a necessary requirement in this agricultural industry and this ensures successful growth of plants and the best outcomes for fruit and vegetable production.

[End transcript}

Integrated pest management in protected cropping

Watch Integrated pest management in protected cropping (4:56)

Jake Byrne describes integrated pest management in protected cropping

Jake Byrne

Biological services

The IPM stands for Integrated Pest Management and it’s a method of controlling pests in a wide range of crops. It involves 3 key components and those are: cultural controls, biological controls and chemical controls.

When developing an IPM program for a crop there’s a few key points which are very important. The first is to identify the crop that you’re working with. After this you must identify key pests and diseases which is specific to this crop. This might vary from region, location, it could vary if you’re growing indoors or outdoors. Cultural control involves plant selection, so choosing plant varieties which are resistant to key pests and diseases. It includes quarantine on farm making sure you’re not bringing in material or people which may have pests or diseases, having adequate screening on the structure so you’re screening out pests from coming in, making sure you don’t have alternative hosts for pests, so that’s weeds around the glasshouse which might attract pests. And on the contrary having plants which will attract beneficial insects towards your crop.

Another key factor is monitoring your crop regularly and thoroughly. So, that involves walking through the crop using a hand lens to identify pests. We’re looking for pests but also beneficial insects. It also means that we can tolerate a low level of pests especially if you have the natural enemies present. Monitoring frequency will depend on the crop type and time of year.

So, if you’re in summer when it’s hot and there’s lots of pests you might walk the crop twice a week, certain times of year once a week would be suitable. Biological controls is really using naturally occurring organisms to help control pests in your crop. This could include applications of bacteria, viral or fungus sprays, it’s utilising naturally occurring insects and mites which might come into your crop. It could also include inundation which is a mass release of beneficials which have been reared in an insectary or inoculation.

So, releasing a small amount preventatively but regularly of an organism which has been reared in an insectary. Rearing of biological controls has been around for a long time, it’s more advanced in Europe than it is in Australia but we’re quickly catching up. It’s an industry which is growing all the time and we’re constantly producing new insects for different pests which may occur. If there’s a pest, there’s usually a predator or a parasite which can control it.

So, IPM doesn’t necessarily mean it’s an organic crop. We still do utilise specific chemicals when it’s necessary instead of using broad spectrum insecticides which will kill a wide range of pests we only spray for specific pests when it’s required. We try to use a lot of softer chemistry which isn’t going to have residual effects on beneficial insects. So, the real key is that you’re only targeting a specific pest if it is present. At this facility they’re growing capsicums, an IPM program for capsicums needs to cover four key pests at least. Those are: Western flower thrip, Two spotted mite, Aphids and Whitefly.

There’s a number of biocontrols that we utilise in a capsicum crop. For Western flower thrips we use Orius which is a predatory bug. It’s important to control Western flower thrip because they’re a virus vector, they can spread Tomato spotted wilt virus which can easily wipe out a capsicum crop. For Western flower thrip we use Orius which is a predatory bug it feeds on all life stages of the thrips and we use Cucumeris which is a predatory mite and this feeds on thrips’ larvae.

Two spotted mite is another serious pest of capsicums and for this we release Persimilis which is a predatory mite. Aphids can cause issue particularly in the hotter months and for this we use an inoculative release of Aphidius, it’s a parasitic wasp which lays its egg in the Aphid, the larvae hatches inside the Aphid, consumes it from the inside and then emerges from the dead shell of the Aphid. Whitefly can be a pest in some capsicum crops and we also use an inoculative release for that. It’s another parasitic wasp, we use Encarsia and Eretmocerus.

Other things like Two spotted mite if they’re in high levels they can cause mass defoliation to the crop and yeah you will have plant death even in minor levels reduced yield. Yeah, it can be caused by Two spotted mite, Aphids and Whitefly. Whitefly and Aphids in particular also secrete honey dew which causes the produce to become sticky and then mould will grow on that honey dew and yeah, the product becomes unsaleable.

[End transcript}

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