5 Ways to Keep Rats Out of Your Compost

5 Ways to Keep Rats Out of Your Compost

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Finding rats or evidence of the pests in and around your compost bin can be more than a bit unsettling. These persistent rodents have been known to chew through wood, wire, plastic and just about anything else that gets in their way. They multiply at alarming rates; one pair can spawn nearly one thousand baby rats in a year, and they carry diseases. Whether you live in the city, suburbs or country, chances are you may end up having to deal with rats at some point.

In general, rats are looking for two basic things: food and shelter. In some cases, a compost pile ends up being both, and you have a rat problem. There are several simple ways to both prevent rats from getting into your compost pile and for getting them to leave if they’ve already found it.

Bury Food Scraps

Usually, rats are drawn to compost piles because they are easy sources of food. In general, you should never add meat or dairy to a compost pile because those items are a sure draw for rodents (there is an exception to this if you use Bokashi to ferment kitchen waste). If they’re hungry enough, though, your potato peels might start to look pretty tempting. Whenever you add food scraps to the compost bin, either dig in a little and deposit your food waste inside, covering it up again when you’ve added it all or have a couple of inches worth of grass clippings or leaves set aside to layer on top of any food scraps you add.

Don’t Add Food Waste

If rats are a real problem, and you don’t want to have to think about it, forego adding food waste to your compost pile. Don’t waste those valuable scraps, though. Set up a vermicomposting bin for food waste or bury it directly in the garden in compost trenches.

Use Bokashi

If you use Bokashi to deal with your kitchen waste, you are familiar with the odor fermented kitchen waste has. It turns out that even the hungriest rat steers clear of Bokashi fermented food waste. Throw your food waste into the Bokashi bucket, layer with the Bokashi bran, let it sit for two weeks, and then add the contents to your compost pile. It breaks down quickly, and rats won’t even consider touching the stuff.

Keep Contents Moist

One of the two things rats are looking for when they invade your compost is a shelter. A dried-out compost pile not only is inefficient in terms of making compost, but it’s a haven for rats. Just think: It’s a dry, warm, insulated place to sleep that might have a few tasty morsels to snack on. If you make sure your compost pile is always moist throughout—not wet, which results in anaerobic conditions and unpleasant odors—it won’t be a place rats will be interested in making their own. By turning the pile regularly and giving it a bit of water during dry spells, you can make it much less hospitable to rodents.

Plant Mint Nearby

This is one of those tips that seems to work for some people and not for others, but it’s worth a try. Mice and rats are reputed to hate the scent of mint, so if you plant a few mint plants close to your compost pile, it may be enough to deter the little pests. However, if you have a very large or very hungry rat population in your area, it’s unlikely that a little mint will deter them. By putting these tips to work in your compost bin or pile, you can ensure that it is a rodent-free zone.

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4 Good Ways to Get Rid of Chipmunks

Illustration: The Spruce / Emilie Dunphy

There are many ways to control chipmunks, including taking steps for prevention, trapping and releasing, and using homemade chipmunk repellents. Because chipmunks are rodents, many of the same methods used to control chipmunks are similar to those used in rats, mice, and squirrels. But the most humane, and often the most effective, methods are prevention and exclusion.

Preventing and Excluding

The Humane Society recommends making changes to your yard to reduce chipmunk damage and presence. The basic recommendations include:

  • Place L-shaped footers around the home’s foundation as well as any foundations, sidewalks, porches, and retaining walls to keep chipmunks from burrowing.
  • Remove wood or rock piles and trim back plantings; these provide cover or food for chipmunks.
  • Surround the yard or home with a plant-free gravel border.
  • Prevent chipmunks from digging up flower bulbs by planting the bulbs beneath a wire or plastic screen ground cover or in bulb cages. Mesh of 1 x 1 inch is large enough to allow plants to sprout but small enough to deter chipmunk from digging.
  • Plant only bulbs to which wildlife is not attracted, such as daffodils (Narcissus) or Allium.

Other rodent- or pest-proofing techniques that will also help control chipmunks include:

  • Place 1/4-inch mesh hardware cloth around gardens and flowers.
  • Keep firewood and similar piles away from the home to keep chipmunks from burrowing beneath the pile (and possibly under the home’s foundation).
  • Do not allow trees, shrubs, or other plantings to run continuously from wooded areas to the home, as this will draw chipmunks in.
  • Do not keep food items outdoors, including pet foods and birdseed, unless it is placed in rodent-proof containers.

Watch Now: How to Get Rid of Chipmunks

Using Repellents

There are no repellents specifically registered for use against chipmunks, and the use of repellents is somewhat controversial. Although the Missouri Department of Conservation advises that fumigants and repellents “are not recommended because none are known to be effective,» the Humane Society states that “commercial repellents that promise to repel squirrels will also repel chipmunks.” Some squirrel repellents include Note: Follow all manufacturer safety warnings when using any repellent product:

  • Thiram applied to plant bulbs, stems or bark
  • Mothballs or flakes (Naphthalene) placed around gardens
  • To make a homemade chipmunk repellent, mix together:
    • 1 teaspoon Lysol
    • 3 ounces Epsom salt
    • 1-gallon water

Warning

Commercial products containing thiram, bitrex, nicotine sulfate, methyl nonyl ketone crystals, and polybutene applied to plants that are not to be eaten by humans; applications may need to be repeated because rain and watering can wash them away.

Trapping and Releasing

Trapping and relocating a chipmunk far from your home is an ethical way to deal with a particularly persistent animal. Check the local laws and recommendations for relocating chipmunks in your area before attempting to trap a chipmunk. Relocation may not be legal in all areas. Follow these basic tips for trapping and relocating a chipmunk:

  • Choose a small trap (approximately 10 to 20 inches long) with small wire mesh so the chipmunk cannot escape.
  • Place the trap in areas of known chipmunk activity, including traffic paths and near burrows (if you can find them). Locations undercover are better than exposed areas.
  • Bait the trap so that chipmunks can’t retrieve it from outside the trap. Applying peanut butter directly to the trap’s trigger plate often works well.
  • Check the trap often, and relocate the animal as soon as it is trapped. Release it in a suitable habitat at least five miles from your home, or as specified by local law.

Protecting Bird Feeders

Chipmunks are ground feeders and are attracted to seed spilled from bird feeders. To help keep them away from bird feeders:

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How To Get Rid Of Gnat

How To Get Rid Of Gnat

88 methods on how to get rid of nats fast with home remedies

How to get rid of household insects that flies and bites by identify then Extermination of household insects:
Insects abound in the tropics, and spread into homes and cause a lot of trouble and damage as well as affinity in the transfer and spread of infectious diseases.
And insects commonly found in the home:
Flies – mosquitoes – ants – bugs – cockroaches – moth – mice

To prevent the entry of these insects and their reproduction in the home, then you are advice to do the following:
1. Cleaning the house completely clean.
2. Keeping fouling home and other waste in a rubbish bin airtight lid with into account Fund cleansing between period and another.
3. Renewal conditioned rooms of the house, and a safe food.
4. Fill holes and cracks with cement or gypsum.
5. Cleaning dirty dishes and cooking utensils immediately after use.
6. Put nets or curtains or wire on the windows and doors.
7. Not leave leftover food on the table or in a food closet.

How to kill flies and get rid of its bad flies with home ways: Annihilated flies in the following ways:
1 – sprayed on the kitchen floor one night pesticides and sweep the floor in the morning.
2 – Deadly toxins sprayed for insects on the windows and those infested with flies.
3 – Using any adhesive that leaves them lacquer flies and put in place frequently flies, and leaves the flies by and cleave and annihilated burned paper.
4 – The use of pesticide spraying after being closed windows and doors and then collects and burns.

Get rid of the bad effects of mosquitoes (fleas) and prevent your children from being harmful to mosquito bites:
Frequently mosquitoes in the entities in the areas of wetlands, ponds, swamps, and transmits a lot of dangerous diseases such as fever, malaria and yellow are exterminate mosquitoes in the following way:
1 – Pour oil petroleum (oil) in the discharge water sinks and especially in the summer.
2 – Genocide smoking home sulfur dioxide gas and this process needs to be warned.
3 – The use of pesticide spraying after being closed windows and doors.
4. To get rid of fleas: prose the yeast in the case of dry or fresh garlic, and if you have pets at home, you should comb their fur using this yeast.

Household ways to get rid of rapid cockroaches
1- to exterminate the cockroaches followed by the following:
2- plug nozzle sinks and toilets at night with a piece of tile and more.
3- Pour oil or toxic solvents in the slots sinks and toilets then pour the water in the morning.
4- Throwing balls of flour putty pesticides in the place where cockroaches abound in places far from the reach of children.

Appliances quick ways to get rid of the ants and the effective elimination of them
1- still crumbs and remnants of food on the tables or food cabinet.
2- Placed legs banquets or reservoirs in small jars with water by a layer of petroleum oil.
3- Sprayed cracks that housed it ant insecticide powder.
4. A mixture of fresh powder and vinegar will help to his disappearance.
5. Sprinkle salt or soap water the ants make him run away.
6. There is a banner bearing “No Entry” when used in any form of mint forms.

How to get rid of completely and easily from the moth in your house:
1- woolen clothes are exposed and fur blankets and carpets conditioning and brushing thoroughly cleaned to remove the eggs or small worms, then kept in clean boxes or inside cardboard boxes and cover court with a few mothballs. Or pieces of soap with soap smell good freshener.
2- To maintain clothes moth should be suspended small bags containing a few mothballs or soap.

See also:  Arachnida (Spiders, Scorpions, Mites, and Ticks)

Any way you must follow proven methods in the clothing store to prevent the accumulation of moth:A – clean clothes to be either dry cleaning or hand washing, to be ironed too.
B – The storage area is dry and cold.
C – Clothes that have a fur store in places like hollow dome maintain Vruha.

Getting rid of Insects of rugs: Continuous cleaning of carpets using a vacuum cleaner can save you from dwelling insects similarly hair that it no shelter insects.
Avoid dust accumulation in places where they can be found where the insects at the outer border of the carpet, under furniture … Etc. They are the same sources of nourishment.

Start getting rid of rats in your home before you eat wood doors and lend your kitchen:
1 – extermination of mice using traps where the bait is placed, must be careful to touch it too much because human mice smell a loan for a fast entry.
2 – Wild herb chamomile is placed in places inhabited by rats flee from the smell because they dislike.
3. Placed borax powder (Borax) around the entrances, with keep it away from the reach of hands
4. Preparation of mint tea and then filtered and put it on places that can be frequented by rats.

Get rid of insect or bird’s nest in or around the house.Clothing stored for a long time without the use of such fur or leather on the shelves or drawers are often a source of infection

How to get rid of Flying insects
1- Develop basil leaves or fruit chestnut about to expel insects on fruit.
2- When preparing food in an open place, you light the candles and placed near the meat immature they are working on the expulsion of flying insects until you eat it.
3- It is appropriate solutions: the smell of lavender.

How to get rid of garden insects and how to get rid of outdoor gnats
1- Scattering the ashes of wood on the leaves to avoid the formation of mold on them.
2- Garlic and chili are both effective means against the following insects:
“White flies, Aphids, Leaf hoppers, and Spider mites”

How to use garlic spray for mosquitoes, and how to prepare garlic spray as follows:
1- Mix three cloves of garlic in a blender with fill it halfway with water.
2- Purified water with added when needed.
3- You can add two tablespoons of molasses.

Using hot pepper spray, and how to prepare chili pepper spray as follows:
1- Mix 1/2 cup of chili with two and a half cups of water, with filtered after completing the mixing.
2- Mixes soapy liquid or powder detergent with this water will be sprayed to keep the grass from the garden insects.

An effective way to get rid of the larvae of the butterfly:
To deal with the larvae of butterflies, you do this spray:
Mix the grated or any acidic fruit seeds such as lemon and dipped in the water until the next morning.

How to get rid of the beetle:
1. You can hunt beetle mixing two tablespoons of dishwasher powder with 500 ml of water and then sprayed on the plants.
2. Repeat the process of 5-7 days until complete disappearance of insects, and this spray is also used with the larvae of butterflies.

The Japanese beetle can be eliminated by using the “onion method” as follows:
1 – placed about 5 fruits Onion with 5 fruits Thom after cutting into small pieces in a jar.
2 – Add one teaspoon of vegetable oil.
3 – Close the jar tightly and leave for one day at room temperature.
4 – Strain the mixture into a clean cloth to get rid of the remnants of the onion and garlic juice after making them.
5 – Add 500 mL of water to oil mixture, then two tablespoons of powdered dishwasher.
6 – to set up and use spray day by day, add three tablespoons of the solution with 500 mL of water spraying for 5-7 days (and better timing after sunset or after rain).
7- Radish whereby you can get rid of the potato beetle.

How to get rid of biting gnats for paper and clothing (Silverfish):
The use of lavender and eucalyptus for the protection of these insects.

for more on How to make soap and vinegar mixture to get rid of annoying pesky creatures visit this
full guide to getting rid of larvae of gnats and kill its future generations.

www.howtogetridofgnat.com

Insect Pests Affecting Potatoes in Tropical, Subtropical, and Temperate Regions

  • Jürgen Kroschel
  • Norma Mujica
  • Joshua Okonya
  • Andrei Alyokhin

Abstract

Ensuring the sustainable production of potato is an important challenge facing agriculture globally. Insect pests are major biotic constraints affecting potato yields and tuber quality. The high pesticide uses to control them is of high human and environmental health concern, and it is expected that this will be further exacerbated through impacts of climate change. The chapter provides an overview of the geographical distribution of potato insect pests and their importance in tropical, subtropical, and temperate potato production regions. Climate change will potentially contribute to expand their geographical range of distribution, and increasing populations will lead to greater crop and post-harvest losses. Good progress has been made in applying insect pest modeling in pest risk analysis of potato pests to inform and create better awareness of future pest risks under climate change. Potato pests include some of the species which have evolved resistance to a wide variety of chemicals; and potato growers have already experienced the situation that available chemicals failed to control their targets. This chapter emphasizes the development, use, and adaptation of Integrated Pest Management (IPM) across all potato-growing regions of the world. Ultimately, this will lead to sustainable and more resilient potato production systems not overly dependent on pesticides. IPM requires a good knowledge and understanding of individual potato production systems; identifying pest species, knowing their biology and symptoms of infestation is essential for making educated decisions on their integrated management. To address this need, the chapter provides detailed information for a total of 49 insect pests of potato and the status quo of their management around the world.

Keywords

8.1 Introduction

The potato ( Solanum tuberosum L.) is native to the Andean highlands of South America. Today, potato is produced in more than 149 countries in temperate, subtropical, and tropical agroecologies, demonstrating the versatility and adaptability of this crop to a wide range of environmental conditions. Potato provides humans with an abundant and relatively inexpensive source of high-quality nutrients. Historically, their incorporation into everyday diets commonly coincided with periods of rapid population growth in a variety of nations (Zuckerman 1999 ). Presently, potatoes continue playing a very important role in feeding the human population. The last 30 years were characterized by an explosive growth in their popularity in Asia and Africa, which were previously reliant on other staple crops. Therefore, ensuring sustainability of potato production is currently an important challenge facing agricultural professionals worldwide (Vincent et al. 2013 ). Insect pests are major biotic factors affecting potato yield and tuber quality. Globally, losses are estimated on average at 16% (Oerke et al. 1994 ). Locally, if not routinely controlled, reductions in tuber yield and quality can be between 30 and 70% for various pests (Mujica and Kroschel 2013 ; Kroschel and Schaub 2013 ). The high pesticide use in potato is of high human and environmental health concern, which needs to be addressed by developing and more widely implementing Integrated Pest Management (IPM) approaches.

8.2 Potato Insect Pests’ Geographical Distribution and Invasiveness

Due its global geographical distribution, potato is affected by a wide range of insect pests. In this book chapter we listed and described a total of 49 species: nine major species occurring in tropical and subtropical regions; two major species affecting potato in temperate regions; six major and 32 minor species of temperate, subtropical, and tropical regions. Farmers in tropical and subtropical countries must contend with a higher number of pest species, and with some exceptions, a minimum of 2–4 pests often reach pest status requiring the application of control methods (Kroschel et al. 2012 ). Many pests have evolved in the center of potato origin, and farmers in the Andean region are confronted by a higher number of pests than farmers in Africa or Asia. Some species such as the potato tuber moth, Phthorimaea operculella (Zeller), and the leafminer fly, Liriomyza huidobrensis (Blanchard) have become invasive and occur today as serious pests in many tropical and subtropical regions. In contrast, the strong adaptation of Andean potato weevils, Premnotrypes spp., to the climate of the Andean region and its monophagous feeding habitat on potato and its wild relatives have restricted its distribution. There are, however, still several other pests which could also gain global proportions. Just very recently in 2006, the tomato leaf miner, Tuta absoluta Meyrick, although a more minor pest in potato, was unintentionally introduced to Spain, from where it continued its devastating journey across Africa and into Asia where it reached India within less than 10 years. As farmers had not been prepared and no control measures had been in place, the pest caused large production losses in tomato ( Lycopersicon esculentum Mill .); under certain conditions also potato was more heavily infested as known from South America. The bud midge, Prodiplosis longifilia Gagne, currently with a restricted distribution in Florida and Virginia, and South America (Colombia, Peru, and Ecuador) could become an invasive species supported by its very polyphagous feeding habit. The Colorado potato beetle, Leptinotarsa decemlineata (Say), native to Mexico, has spread across most of the United States, and was introduced into France in the 1920s from where it spread further reaching also parts of China (CABI 2017a ).

8.3 Impacts of Climate Change on Potato Insect Pests

Climate, especially temperature, has a strong and direct influence on the development and growth of insect pest populations. Herbivorous insects—as all other arthropods—are exothermic organisms that cannot internally regulate their own temperature. Their development depends on the temperature to which they are exposed in the environment. A rise in temperature due to climate change may both increase or decrease pest development rates and related crop losses. Hence, an increase in temperature can potentially affect range expansion and outbreaks of many insect pests including pests of potato.

Innovative modeling approaches such as process-based climatic response phenology models (Orlandini et al. 2017 ; Mujica et al. 2017 ; Sporleder et al. 2004 , 2017 ) have been used to assess the effect of temperature increase under projected changes in global temperature for the year 2050 (Kroschel et al. 2016a ) for a wide range of potato pests: P. operculella (Kroschel et al. 2013 , 2016b ); L. huidobrensis (Mujica et al. 2016 ); Guatemalan potato tuber moth, Tecia solanivora (Povolny) (Schaub et al. 2016 ); Andean potato tuber moth, Symmetrischema tangolias (Gyen) (Sporleder et al. 2016 ); the White flies, Bemisia tabaci (Gennadius) and Trialeurodes vaporariorum (Westwood) (Gamarra et al. 2016a , b ).

These predictions have clearly demonstrated that insect pests of potato will respond to climate change by expanding their geographical range of distribution and increasing population densities will lead to greater crop and post-harvest losses. There are, however, distinct differences among the different pest species. The damage potential of P. operculella for example will potentially progressively increase in all regions where the pest already prevails today, with a range expansion into temperate and tropical mountainous regions (Kroschel et al. 2013 , 2016b ). In comparison, L. huidobrensis is much less adapted to warmer climates and climate change will differently affect this species. The global predictions clearly indicate a slight to moderate decrease in the establishment potential of the pest in most of the tropical and subtropical potato production areas, but still with high pest risks. Further, a range expansion into temperate regions of Asia, North and South America, and Europe, as well as into subtropical and tropical mountainous regions is expected, with a moderate increase of its establishment and damage potential (Mujica et al. 2016 ). A further range expansion into tropical mountainous regions such as the Andes has been also predicted for T. solanivora and S. tangolias (Quiroz et al. 2018 ).

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Potato production systems of tropical countries are highly susceptible to pest infestations due to often year-round favorable climatic conditions for pest population growth and host plant availability. Even smaller changes in temperature predicted for tropical regions compared to temperate regions will have stronger consequences on pest development due to already higher existing metabolism rates of organisms such as insects (Dillon et al. 2010 ). This does affect not only the general life cycle of an insect pest but also all other biological processes, including feeding rates, plant growth, and activity of biotic antagonist. Lessons have been learnt from the El Niño phenomena to better understand possible climate change effects on pest abundance and severity in tropical production areas. During the 1997 El Niño phenomena in Peru, the mean temperature on the Peruvian coast increased by about 5 °C above the annual average. While infestation of potato by L. huidobrensis decreased, infestations by all other pests increased in agricultural and horticultural crops. The farmers’ only adaptive strategy to cope was to apply high doses of pesticides every 2–3 days (Cisneros and Mujica 1999a ).

8.4 Insect Pest Control with Insecticides in Potato

Potato foliage contains a considerable amount of glycoalkaloids, which provide at least some protection from herbivory. Nevertheless, they are attacked by a robust complex of phytophagous insects, some of which can destroy the potato crop in the absence of adequate control measures. Just as with most other cultivated plants, management of insect pests of potato is achieved predominantly through application of pesticides. By some estimates, potatoes are the most chemically dependent crop in the world (Vincent et al. 2013 ). Insect pests are not the only factor responsible for this notoriety, as large amounts of fungicides are used to combat diseases caused by fungi and oomycetes. Still, insecticides remain to be a foundation of insect pest management in most potato fields around the world, and their use can be rather heavy at times.

Although insecticides have been largely successful in keeping potato production going, there are serious and well-known concerns about long-term sustainability of this approach. Nontarget effects of insecticides on a variety of organisms, including humans and beneficial insects, gained considerable notoriety since 1960s. The use of highly hazardous pesticides in potato in countries such as Ecuador and Peru has caused serious health risks to farmers (Orozco et al. 2009 ). Worldwide decline in beneficial pollinators documented in the early 2000s provided additional fuel to the fire of public apprehension of using toxic chemicals in agriculture. Furthermore, as discussed in the following section, more and more insecticides have lost their efficiency due to resistance development in insect populations (Alyokhin et al. 2013 , 2015 ).

As more and more insecticides are becoming phased out due to environmental concerns or become ineffective due to resistance development in targeted insect populations, the number of options available to potato growers dwindles. Developing replacement insecticides is an increasingly difficult and expensive task, and it is highly questionable that a plethora of new active ingredients will regularly appear on the market in perpetuity (Alyokhin et al. 2015 ). Therefore, good stewardship of existing chemicals and, whenever possible, their replacement with nonchemical control alternatives become an increasingly important business strategy for the pesticide industry and potato farmers. Therefore, this chapter puts a considerable emphasis on describing various nonchemical management options for insect pests.

In the modern age of industrialized agriculture, a farmer field is often considered to be a type of a production facility. Although there is a certain element of truth to such an approach, it is important to remember that it is still comprised of living organisms that are interacting with each other and with their environment. In other words, it is an ecosystem, with the same basic characteristics as all other ecosystems on Earth. This includes evolutionary processes leading to adaptation to a particular set of environmental conditions through survival and reproduction of specific genotypes. In many cases, such an adaptation means developing an ability to survive exposure to insecticides, a phenomenon known as insecticide resistance (Alyokhin et al. 2015 ).

Potato pests include some of the species that are most prone to evolving resistance to a wide variety of chemicals. The Arthropod Pesticide Resistance Database ( 2018 ) lists 469 cases of green peach aphid ( Myzus persicae (Sulzer)) resistance to a total of 80 active ingredients; 300 cases of Colorado potato beetle ( Leptinotarsa decemlineata (Say)) resistance to a total of 56 active ingredients; 111 cases of greenhouse whitefly ( T. vaporariorum) resistance to 27 active ingredients; and 501 cases of two-spotted spider mite ( Tetranychus urticae C. L. Koch) resistance to rather impressive 95 active ingredients. The extent of resistance is likely to be underestimated because not every case of its development is entered into the database. It is possible that the ability to deal with toxic glycoalkoloids contained in potato foliage serves as a preadaptation to resisting chemical toxins made by humans (Alyokhin and Chen 2017 ). Not every population of a given pest species is resistant to all compounds that have been recorded to fail against that species. However, these statistics vividly illustrate the seriousness of the problem. On several occasions, potato growers already experienced the situation when virtually all commercially available chemicals failed to control their targets (Alyokhin et al. 2013 ). It is very likely that such a situation will arise again in the foreseeable future. Therefore, we need to be proactive to prevent this from happening.

Monitoring insecticide efficacy. Larger than usual number of surviving pests may indicate that their population is becoming resistant.

Avoiding applications of the same or related products repeatedly throughout a growing season. Instead, application schedule should consist of a sequence of insecticides with different modes of action. Information on a product’s mode of action is available from its manufacturer.

Applying insecticides at rates that are not lower than a recommended minimum. Otherwise, heterozygotes will survive and breed with each other. Following Mendelian laws of inheritance, some of their offspring will become homozygously resistant and capable of surviving even the recommended insecticide rates.

Applying insecticides only when pest populations are sufficiently high to cause economically important damage. Therefore, the use of control thresholds developed for different potato pests is highly recommended. Trying to kill every single insect will, by definition, result in the survival of only highly resistant genotypes.

Whenever possible, leaving parts of the field untreated to allow susceptible pests to survive and interbreed with resistant pests. Because resistance is almost never completely dominant, resulting heterozygotes will be killed by insecticides.

The use of insecticide applications should be not the first but the ultimate control option in an IPM approach after all other management options could not prevent to keep a specific pest population under the economic threshold.

8.5 Integrated Pest Management in Potato

Integrated Pest Management (IPM) is defined as an “ecosystem approach to crop production and protection that combines different management strategies and practices to grow healthy crops and minimize the use of pesticides.” It means “a careful consideration of all available pest control techniques and subsequent integration of appropriate measures that discourage the development of pest populations and keep pesticides and other interventions to levels that are economically justified and reduce or minimize risks to human health and the environment. IPM emphasizes the growth of a healthy crop with the least possible disruption to agro-ecosystems and encourages natural pest control mechanisms” (FAO 2018 ). It has been also defined as “a decision support system for the selection and use of pest control tactics, singly or harmoniously coordinated into a management strategy, based on cost/benefit analyses that consider the interests of and impacts on producers, society, and the environment” (Kogan 1998 ).

Although IPM has been widely promoted by researchers, policymakers, and agricultural practitioners, it is still very far from being universally adopted, but there have been large shifts towards bringing it into the mainstream of agricultural production. Since 2014, for example, a European Union (EU) Directive has obliged all professional plant growers within the Union to apply the general principles of IPM (European Parliament and the Council of the European Union 2009 ). To make IPM, however, successful, integrating several methods to combat pests requires interdisciplinary research and effective nonchemical control methods for all pests in a specific crop agroecology to fully avoid or minimize the pesticide use. But many research programs working on IPM still focus on single plant protection methods and not on a systematic study of the compatibility and optimization of simultaneously implemented pest management elements (Stenberg 2017 ). The International Potato Center (CIP) has developed a holistic working framework for potato pest management research and development and its application by farmers. This approach led, for example, to the development of IPM for different potato agroecologies in Peru under smallholder production considering ecological, economic, and environmental benefits (Mujica and Kroschel 2018 ; Kroschel et al. 2012 ). Further, Horn and Page ( 2008 ) reported from a successful potato IPM program for large-scale potato growers in Australia.

Application of best cultural practices, which includes the use of healthy seed, suitable crop rotations, and intercropping systems among others which also support natural biological control.

Correct and timely pest identification and regular monitoring of population development. This applies the use of monitoring tools such as pheromone- or physical-based trapping methods (e.g., yellow sticky traps). Educated pest management takes advantage of specific aspects of pest biology that can be used to diminish its populations in one way or another. It should also be preventative, initiated before the occurrence of economic losses.

Application of economic thresholds. Attempts on complete pest elimination are costly, often futile, and generally counterproductive. A control action should be taken only when the cost of damage due to injury by a pest exceeds the cost of the control action. Control thresholds have been developed for several potato pests, but they need to be verified and adjusted for the conditions of a specific location and potato variety.

Using diverse control tactics in a complementary or, whenever possible, synergistic ways. Pesticides are the ultimate option integrated with cultural, biological, regulatory, and other controls to result in a unified multi-pronged attack against pest populations.

Evaluating results. This component is often overlooked, but very important. Efficiency of IPM control programs should be continuously monitored to make necessary adjustments when needed considering economic, ecological, and environmental assessments.

Among other benefits, IPM is likely to dramatically slow down evolution of insecticide resistance. Simultaneous adaptations to diverse and unrelated management techniques will require statistically unlikely genetic changes in pest populations (Alyokhin et al. 2015 ). As a result, integrating different techniques is likely to reduce our reliance on the “pesticide treadmill” of constantly replacing failed chemicals. With all its advantages, IPM should be made available to farmers across all potato-growing areas of the world. Practicing this approach requires, however, a good understanding of individual production systems down to a single-field level and knowing their specific components. Identifying pest species and knowing their biology is essential for making educated decisions on their management. To address this need, the following subchapters provide an overview of major and minor insect pests of potato and their management around the world.

8.6 Major Pests in Tropical and Subtropical Regions

8.6.1 Potato Tuber Moths

Phthorimaea operculella (Zeller, 1873),

Tecia solanivora (Povolny, 1973) (Lepidoptera: Gelechiidae)

Distribution

Adult female of Phthorimaea operculella ( a) and symptoms of larvae infestation on leaves, stems, and tubers ( b, c, d). (Photo credits: CIP)

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Adult male and female of Symmetrischema tangolias ( a), and symptoms of larvae infestation on stems and tubers ( b, c). (Photo credits: CIP)

Adult male of Tecia solanivora ( a), and symptoms of larvae infestation on tubers ( b). (Photo credits: CIP)

Host range

P. operculella is an oligophagous pest (i.e., an insect feeding on a restricted range of food plants) of vegetable crops that belong mainly to the family Solanaceae: potato ( Solanum tuberosum L.), tomato ( Lycopersicon esculentum Mill .) , and tobacco ( Nicotana tabacum L.). Also, wild species of the Solanaceae family, including important weeds, e.g., black night shade ( Solanum nigrum L.) are hosts. In total, the host range comprises 60 species. Further, crops of the family Chenopodiaceae are attacked including eggplant ( Solanum melongena L .), bell pepper ( Capsium annuum L .), Cape gooseberry ( Physalis peruviana L .), aubergine (S . melongena L .), and sugar beet ( Beta vulgaris L.). S. tangolias has a more restricted host range comprising of potato, tomato, sweet cucumber ( Solanum muricatum Aiton), poroporo ( Solanum aviculare G. Forst), kangaroo apple ( Solanum laciniatum Aiton), black nightshade, and bell pepper. T. solanivora is monopahagous attacking only potato.

Symptoms of infestation

P. operculella attacks potato by mining the leaves and stems and by feeding on the tuber. Mines are the typical symptoms of leaf damage caused by the larvae eating the mesophyll without damaging the upper and lower epidermis. When the foliage dies, the larvae enter the soil through cracks where they may eventually find and feed upon tubers. Larvae enter potato tubers via the eyes and continue to bore or tunnel through the tuber just below the skin. Larval excreta are pushed out through the holes, which can be observed immediately after larvae start their mining activity. Larvae of APTM enter the potato stem making a small hole in the plant axils (between stem and lateral petioles). From this hole, galleries made by the larvae run downward within the stem. Excreta are pushed out through the initial hole made by the larva. When stems are severely damaged, the upper part of the stem wilts or the whole plant collapses. Young plants can suffer tip death from boring larvae. Eggs may be found in slits on the stem of a food plant. In tubers, larvae enter through potato eyes. Initially, the small hole can hardly be seen by the naked eye. As in stems, larval excreta are then pushed out through the hole, which becomes apparent after several days of mining activity. Inside the tuber, the larva tunnels just under the surface at first, but later penetrates more deeply. GPTM larvae feed exclusively on tubers during potato cultivation and during storage. Damage is caused by larvae that bore galleries into the tubers. After the larvae have left tubers, the exit hole is clearly visible. In potato fields, T. solanivora attack occurs from tuberization until harvest (Kroschel and Schaub 2013 ; Niño 2004 ). Tubers infested by either of the three species develop a bitter taste and are unsuitable for human or livestock consumption (Keller 2003 ; Kroschel and Schaub 2013 ).

Impacts on production losses

P. operculella. Under heavy field infestation, potato foliage can be destroyed, which can result in substantial yield loss of up to 70%. High infestations early in the season can directly affect tuber yield. Strong correlation exists between leaf and consequent tuber infestation, which suggests that reducing P. operculella population density during the growing period is key to reducing potato tuber infestation at harvest. Hence, the most devastating yield losses are largely a result of earlier tuber infestation in the field, generally where moths have laid eggs through soil cracks on the developing tubers, or when harvest is delayed. P. operculella also damages harvested potato tubers in storage. The damage to potatoes in rustic stores can be total within a few months if the tubers are left untreated. Infested tubers are unsuitable not only for human consumption but also for use as seed. Infested tubers produce fewer yields and initiate a fast development of a new field P. operculella population (Kroschel and Schaub 2013 ; Kroschel et al. 2012 ; Keller 2003 ; Kroschel 1994 , 1995 ).

S. tangolias. This species has become an economically important pest in potato fields and in storage in mid-elevation regions of the Andes (Peru, Bolivia, and Ecuador); its status in Colombia is not well confirmed. In the Andes, losses in the field may reach up to 30%, but most economically significant damage occurs when infested tubers are transferred to potato stores where reinfestation takes place. Without adequate management, farmers can completely lose their house-stored potatoes within 3–4 months of storage. In Australia and New Zealand, where the pest was accidentally introduced from South America, it is more recognized as a local pest of tomato, poroporo, sweet cucumber and other Solanaceae crops, and is commonly referred to as “tomato stem borer.” However, at national level it is considered a minor pest and its economic impact on these crops is not well reported in the literature (Kroschel and Schaub 2013 ; Keller 2003 ).

T. solanivora. Complete losses of harvested tubers have been observed occasionally after the invasion of the pest into new areas when farmers were not yet familiar with pest control. Generally, tuber damage rates at harvest vary between 2 and 15% in the Andean region. When infested potato tubers are stored without application of control methods T. solanivora can destroy, depending on the storage period and temperature, of whole potato stock (Kroschel and Schaub 2013 ; Niño 2004 ).

Methods of prevention and control

Control of the potato tuber moths must take place both in the field and in storage. Implementation of integrated pest management is recommended to reduce the pest problem in field and stores. T. solanivora is the most difficult potato moth to control as the larvae feed only inside potato tubers where they are hard to reach (Kroschel and Schaub 2013 ; Kroschel et al. 2012 ; Keller 2003 ; Pollet et al. 2003 ; Kroschel 1995 ).

Monitoring with pheromone traps. For all three potato tuber moth species sexual pheromones have been identified and synthesized. They are used for monitoring the flight activity of adult male populations to detect early the presence of the different moths in the field and store to take adequate control measures.

Cultural practices. Some common practices for potato tuber moths are the use of pest-free seed tubers, deep planting, regular irrigation to avoid soil cracking, high hilling to protect tubers, timely harvest, not leaving the tubers after harvest exposed in the field for a long time (especially throughout the night), i.e., harvest and store immediately, and removal of leftover tubers to reduce the overwintering field population. Also, early maturing varieties can contribute to reduced risk of infestation.

Biological control. Classical biological control can be an effective strategy in all those regions in which the pests has been unintentionally introduced to keep the pest population below economic threshold; for this approach, the species Copidosoma koehleri (Blanchard), Apanteles subandinus (Blanchard), and Orgilus lepidus (Muesebeck) have been widely and successfully used (Canedo et al. 2016a , b , c ; Kroschel and Schaub 2013 ).

Biopesticides. Microbial biopesticides for P. operculella field control have been tested based on Bacillus thuringiensis subsp. kurstaki ( Btk) and P. operculella-specific granulovirus ( PhopGV, Baculoviridae). Btk was effective but required repeated applications because it is quickly degraded by UV light. Likewise, PhopGV has shown mixed results. To protect PhopGV against UV inactivation a variety of adjuvants (e.g., dyes, optical brighteners) have been tested but simple preparations of PhopGV-infected larvae macerated in water were superior. Applications of PhopGV doses sufficient to cause >95% mortality are considered not being economical, and low dose treatments are proposed for a relatively inexpensive partial suppression of the field population (Lacey and Kroschel 2009 ; Sporleder and Kroschel 2008 ; Kroschel and Sporleder 2006 ; Sporleder 2003 ; Kroschel et al. 1996 ).

Attract-and-kill. This approach has been developed to control of P. opercullela and S. tangolias under field and storage conditions. It consists of a co-formulation of the insect pest-specific sexual pheromone, which “attracts” males, and a contact insecticide at very low concentration which “kills” males getting in contact with the product. The oil formulation is applied at a droplet size of 100 μL using a special handheld applicator; it is applied at 2500 droplets/ha. It effectively reduces the male population and the number of offspring, hence controlling larvae damage in the crop. It provides pest-specific control, and is harmless to natural enemies, humans, and the environment (Kroschel and Zegarra 2010 , 2013 ). In Peru, the two products AdiosMacho- Po ® and AdiosMacho- St ® have been registered to be commercialized in Peru and the Andean region.

Chemical control. Broad-spectrum insecticides have been commonly used to suppress potato tuber moth population and economic damage, but which has been associated with many negative effects causing resistance of the pests to various active ingredients and affecting farmers and the environment.

Integrated Pest Management. Effective IPM practices for potato tuber moths have been developed, which can be applied successfully if potato tuber moths are the only economically important pests in an agroecosystem (e.g., Republic of Yemen, Kroschel 1995 ). However, potato is often affected by several pest species which requires a system approach to manage all economically important potato pests (Kroschel et al. 2012 ). This means effective IPM practices are required for all pests to fully eliminate or minimize the use of insecticides.

Storage management

Potato tuber moth infestation occurs frequently in rustic farmer-managed potato stores in developing countries, especially if temperature is suitable for rapid population build up and the storage lasts for several months. Storage facilities should be cleaned thoroughly before potato tubers are stored. Fine netting at windows should protect adult moths from entering storage facilities. Only healthy tubers should be selected for storage. Infested potato tubers need to be destroyed. However, initial infestations cannot be easily observed and are the main reasons why potato tuber moths enter storage facilities and infest potato. Sex-pheromone-baited water traps or funnel traps (Delta) can be used for monitoring the moth presence but in known region of potato tuber moths’ occurrences, potatoes should be treated before storage.

Biopesticides. Biopesticides based on Btk and PhopGV are used in potato tuber moth storage control. The microbials are formulated in inert materials (e.g., talcum) and dusted over potatoes before storage. Since PhopGV is only effective in P. operculella and T. solanivora, in regions where all three species occur simultaneously, the use of Btk has the advantage to control all three species. Further, Btk is mostly available as a commercial biopesticide while PhopGV has to be multiplied in potato tuber moth larvae. The product Matapol, e.g., is a co-formulation between Btk and PhopGV, commercialized in Bolivia. It has also been shown that inert materials (e.g., calcium carbonate, kaolin, talcum, silicium rich sand) can be used effectively without the addition of active biologicals ( Btk, or PhopGV) as they control first instar larvae through desiccation (Kroschel and Koch 1996 ; Mamani et al. 2011 ; Sporleder and Lacey 2013 ; Schaub and Kroschel 2017 ).

Attract-and-kill. Attract-and-kill formulations (see above) can be applied at a density of one drop (100 μL)/qm of storage area to reduce the male population and hence tuber infestation in potato stores (Kroschel and Zegarra 2013 ).

Chemical control. Malathion dust (WHO Class III) is often observed to be sold in developing countries to treat stored tubers. This is especially critical if precautions are not taken properly by farmers and potatoes are stored in living areas. Pyrethroids (e.g., fenvalerate) have shown to be highly effective equally to Btk treatments described above (Kroschel and Koch 1996 ).

8.6.2 Pea Leafminer Fly

Liriomyza huidobrensis Blanchard (Diptera: Agromyzidae)

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