Grasshoppers: Introduction, Description, Characteristics, Life Cycle, and, Control
Grasshoppers are insects belonging to the suborders Caelifera and Ensifera of the Orthoptera order. To distinguish them from katydids, which have much longer antennae, they are frequently referred to as short-horned grasshoppers (Caelifera) (Ensifera). These insects are hemimetabolous. The three stages of the life cycle—Egg, Nymph, and Adult—complete it. The nymph went through five moults, each time resembling the adult insect more. Some grasshopper species can alter their colour and behaviour as well as create swarms when the population density is high and the environmental circumstances are right. They are referred to as locusts when this occurs. Grasshoppers are plant-eating insects that can occasionally cause major damage to pasture, vegetables, and grains, particularly when they swarm in the millions like locusts and decimate crops over large areas. As a result, they are categorized as mixed and oligophagous feeders (Mulkern 1967). They are crucial ground invertebrates in the grassland ecosystem from a functional standpoint (Scott 1979 and Risser 1981). They frequently serve as the primary invertebrate in the grassland ecosystem’s consumer community and are a key source of food for many predatory species, such as birds (Joern 1986 and Samways 1997). There are 1,750 species of orthoptera recognized in India out of the world’s almost 20,000 species (Tandon and Hazra 1998). The majority of species are tropical, however, they are also widely found in temperate regions. Grasshoppers can occasionally turn into significant pests on field crops, ornamentals, and vegetable crops. The most frequent hosts for these pests are grasses and other herbaceous plants, but after consuming those hosts, grasshoppers frequently switch to eating vegetables, field crops, leaves, or even the sensitive bark of shrubs and trees.
Adult grasshoppers have expanded hind legs that are designed for jumping, short, threadlike antennae, chewing mouthparts, thin front wings, and broad, fan-shaped hind wings.
1. Grasshoppers have a head, thorax, and abdomen, which is the normal structure for insects.
2. With the mouth at the bottom, the head is held vertically at an angle to the body. Three basic eyes that can sense light and dark, a huge set of compound eyes with all-around vision, and a pair of thread-like antennae with touch and odour receptors are all found on the head. Two sensory palps are located in front of the jaws, and the mouthpieces pointing downward have been adjusted for chewing.
3. The segmented thorax and abdomen contain a hard cuticle consisting of chitin-based plates that overlap. Three pairs of legs and two pairs of wings are attached to the three fused thoracic segments. The hindwings are big and membranous with veins that give them strength, while the forewings, or tegmina, are slender and leathery. Claws for grasping are present at the ends of the legs. The hind leg is especially strong; the femur is sturdy and has several ridges where different surfaces combine, and the inner ridges in some species have stridulatory pegs. A double row of spines is present on the tibia’s posterior edge, and two articulated spurs are located close to the lower end. The muscles that manage the wings and legs are located inside the thorax.
4. The tympanal organ and hearing system is located in the first of the eleven segments of the abdomen, which is united to the thorax. Flexible membranes connect the ring-shaped segments two through eight. Segments nine through eleven are smaller and feature a pair of cerci, while segments 10 and eleven contain the reproductive organs. Typically, female grasshoppers are larger than males and have shorter ovipositors. The word “Caelifera,” which refers to the form of the ovipositor, is derived from Latin and means “chisel-bearing.”
5. The majority of species that produce loud noises do so by rubbing their forewing margins with a row of pegs on their hind legs (stridulation). Although in some species the females also stridulate, the sounds are primarily made by males to entice females.
6. Grasshoppers and crickets can be mistaken for one another, but they differ in several ways, including the number of segments in their antennae, the shape of the ovipositor, the placement of the tympanal organ, and the mechanisms employed to make a sound. While caeliferans have shorter, stouter antennae with more segments, ensiferans have antennae that can be significantly longer than the body and have at least 20–24 segments.
The majority of grasshoppers spend the entire year living and mating in the same place. Some species may experience such rapid growth in numbers that they are compelled to leave their breeding grounds. In the late summer and early fall, females deposit elongated, 1- to 3-inch masses of eggs in the soil. Typically, eggs are laid in grain stubble, fence rows, ditchbanks, and meadows. The overwintering stage is the egg. Hatching can start as early as late February in the spring. Immatures, or young nymphs, look for food in the neighbourhood. As they grow larger and exhaust the local host plants, the grasshoppers are compelled to travel in search of alternative food sources. Grasshoppers take 40 to 60 days to reach adulthood. The female’s mate, and then they start to lay eggs. Due to variations in hatching time and developmental rate, oviposition (egg-laying) lasts for about three months. Over a few weeks, a single female may produce 200–400 eggs. Adults keep eating after oviposition until the cold kills them. In Tennessee, certain species may have more than one generation per year. The environment has an impact on changes in grasshopper population levels. A season like this would result in high mortality: a warm spring that causes eggs to hatch too early, followed by cooler temperatures that prevent normal growth, a brief hot spell that is conducive to grasshopper diseases, and cool summer and early fall that postpone maturity and shorten the time needed to lay eggs. Grasshopper outbreaks are favoured by a succession of warm, dry seasons.
Natural predators control grasshopper numbers. Some insects, including ground beetles, blister beetles, and bee flies, lay their eggs close to grasshopper eggs that are overwintering in the soil. According to studies, the larvae of these predators are capable of decimating up to 60% of grasshopper egg masses laid across a wide area. Grasshoppers are a common food source for many mammals, birds, and predatory insects. The growth of naturally existing microorganisms and the subsequent infection of grasshoppers may be favoured by specific environmental factors.
In cases where natural defenses are insufficient, insecticidal control may be required. They frequently enter from nearby pastures, fencerows, and roadside edges, which is a significant concern when trying to get good control of grasshoppers. In such circumstances, it could be required to treat the surroundings of the crop to fully safeguard it from migratory grasshoppers. In other words, it is frequently more crucial to treat the surrounding region than it is to treat the crop you are attempting to preserve if significant numbers of grasshoppers are coming into your field from nearby places. For the majority of garden and field crops, the insecticides carbaryl (Sevin) or malathion are permitted. These three pesticides can be used on lawns and many ornamentals, together with cyfluthrin (Tempo), bifenthrin (Talstar), deltamethrin (DeltaGard), and lambdacyhalothrin (Scimitar). Golf courses, sod farms, road medians, and industrial plant sites are permitted for the use of chlorpyrifos (Dursban), but residential landscapes are not. For advice on specific host plants for controlling grasshoppers, get in touch with your county Extension office.
A carbaryl bait with 2 to 10% active carbaryl can be created by mixing Sevin XLR Plus with a cereal grain substrate (cereal grains or their by-products, such as flaky wheat bran, rolled wheat, rolled oats, and/or barley or oat millings). Between the crop that needs to be protected and the hatching beds, these carbaryl baits work best when applied over mowed or barren terrain. The grassy areas, especially those with southern exposure and more sandy soil, are where grasshoppers tend to lay the majority of their eggs. These areas are known as the hatching beds. The hatching beds can be baited with wheat bran and Nosema locustae (Semaspore Bait), a protozoan that is harmful solely to grasshoppers. Semaspore Bait should infect the majority of the remaining grasshoppers while killing around half of them. The few eggs the diseased survivors lay are also contaminated, and they do not consume much. They can spread disease to other grasshoppers if they are eaten. Infected egg cases and cadavers both allow the protozoan to survive the winter.
Frequently Asked Questions
Question: What is an interesting fact about grasshoppers?
Ans: Grasshoppers consume plants and other types of vegetation since they are herbivorous. Without using its wings, a giant grasshopper may jump between 10 and 20 times the length of its body. With its wings, a grasshopper can jump up to eight miles per hour.
Question: Is grasshopper harmful to humans?
Question: Are grasshoppers poisonous?
Question: Where does a grasshopper live?
Ans: They live on grass
Question: What is a grasshopper eat?
Ans: Green Plants
Question: Do grasshoppers sleep?
Question: How long does a grasshopper live?
Ans: They live for about one year