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Ordo Hymenoptera

The Hymenoptera are one of the largest orders of insects, comprising the sawflies, wasps, bees and ants. Over 130,000 species are recognized, with many more remaining to be described. The name refers to the wings of the insects, and is derived from the Ancient Greek ὑμήν (hymen): membrane and πτερόν (pteron): wing. The hindwings are connected to the forewings by a series of hooks called hamuli.

Females typically have a special ovipositor for inserting eggs into hosts or otherwise inaccessible places. The ovipositor is often modified into a stinger. The young develop through complete metamorphosis — that is, they have a worm-like larval stage and an inactive pupal stage before they mature (See holometabolism).

he term Hymenoptera was coined by Carl Linnæus in 1773 from the Greek hymenos, meaning membrane, added to pteron, which means wings. This, therefore, denotes the species contained within the particular order bear membraned wings.
Hymenoptera originated in the Triassic, the oldest fossils belonging to the family Xyelidae. Social hymenopterans appeared during the Cretaceous.

Hymenoptera range in size from very small to large insects, and usually have two pairs of wings. Their mouthparts are adapted for chewing, with well-developed mandibles (ectognathous mouthparts). Many species have further developed the mouthparts into a lengthy proboscis, with which they can drink liquids, such as nectar. They have large compound eyes, and typically three ocelli.

The forward margin of the hind wing bears a number of hooked bristles, or "hamuli", which lock onto the fore wing, keeping them held together. The smaller species may have only two or three hamuli on each side, but the largest wasps may have a considerable number, keeping the wings gripped together especially tightly. Hymenopteran wings have relatively few veins compared with many other insects, especially in the smaller species.

In the more ancestral Hymenoptera, the ovipositor is blade-like, and has evolved for slicing plant tissues. In the majority, however, it is modified for piercing, and, in some cases, is several times the length of the body. In some species, the ovipositor has become modified as a sting, and the eggs are laid from the base of the structure, rather than from the tip, which is used only to inject venom. The sting is typically used to immobilise prey, but in some wasps and bees may be used in defense.

The larvae of the more ancestral Hymenoptera resemble caterpillars in appearance, and like them, typically feed on leaves. They have large chewing mandibles, three thoracic limbs, and, in most cases, a number of abdominal prolegs. Unlike caterpillars, however, the prolegs have no grasping spines, and the antennae are reduced to mere stubs.

The larvae of other Hymenoptera, however, more closely resemble maggots, and are adapted to life in a protected environment. This may be the body of a host organism, or a cell in a nest, where the adults will care for the larva. Such larvae have soft bodies with no limbs. They are also unable to defecate until they reach adulthood due to having an incomplete digestive tract, presumably to avoid contaminating their environment.
Among most or all hymenopterans, sex is determined by the number of chromosomes an individual possesses. Fertilized eggs get two sets of chromosomes (one from each parent's respective gametes), and so develop into diploid females, while unfertilized eggs only contain one set (from the mother), and so develop into haploid males; the act of fertilization is under the voluntary control of the egg-laying female. This phenomenon is called haplodiploidy.

However, the actual genetic mechanisms of haplodiploid sex determination may be more complex than simple chromosome number. In many Hymenoptera, sex is actually determined by a single gene locus with many alleles. In these species, haploids are male and diploids heterozygous at the sex locus are female, but occasionally a diploid will be homozygous at the sex locus and develop as a male instead. This is especially likely to occur in an individual whose parents were siblings or other close relatives. Diploid males are known to be produced by inbreeding in many ant, bee and wasp species. Diploid biparental males are usually sterile but a few species that have fertile diploid males are known.

One consequence of haplodiploidy is that females on average actually have more genes in common with their sisters than they do with their own daughters. Because of this, cooperation among kindred females may be unusually advantageous, and has been hypothesized to contribute to the multiple origins of eusociality within this order. In many colonies of bees, ants, and wasps, worker females will remove eggs laid by other workers due to increased relatedness to direct siblings, a phenomenon known as worker policing.

Different species of Hymenoptera show a wide range of feeding habits. The most primitive forms are typically herbivorous, feeding on leaves or pine needles. Stinging wasps are predators, and will provision their larvae with immobilised prey, while bees feed on nectar and pollen.

A number of species are parasitoid as larvae. The adults inject the eggs into a paralysed host, which they begin to consume after hatching. Some species are even hyperparasitoid, with the host itself being another parasitoid insect. Habits intermediate between those of the herbivorous and parasitoid forms are shown in some hymenopterans, which inhabit the galls or nests of other insects, stealing their food, and eventually killing and eating the occupant.

Sekilas Trichogramma

Trichogramma adalah tawon polifag , umumnya dikenal sebagai 'tawon stingless', yang endoparasitoids telur serangga. Endoparasitoids bertelur di telur atau larva dari spesies lain. Saat ini di dunia ada spesies hewan diperkirakan 50 juta dengan 1,7 juta yang telah dijelaskan. Dari jumlah tersebut, tujuh puluh lima persen diyakini serangga. Trichogramma mewakili sekitar 80 genera dari keluarga trichogrammatidae dengan lebih dari 800 spesies di seluruh dunia.
Anggota keluarga trichogrammatidae kisaran ukuran 0,2-1,5 mm. Sarana kunci penyebaran meliputi melompat berjalan dan pendek. Orang dewasa membutuhkan gula sebagai sumber energi yang diperoleh dari nectars,, melon tanaman getah dan gula dilarutkan melalui floem. Mereka terjadi secara alami dalam berbagai habitat di seluruh dunia dan memiliki kemampuan untuk parasitize spesies inang banyak. Host utama mereka adalah telur dari spesies Lepidoptera dan lainnya seperti Hymenoptera, Neuroptera, Diptera, Coleoptera dan Hemiptera.
Meskipun ada beberapa parasitoid telur yang umum digunakan di seluruh dunia, Trichogramma telah menjadi yang paling ekstensif dipelajari. Ada lebih dari seribu makalah yang diterbitkan pada Trichogramma dan mereka adalah agen kontrol yang paling digunakan hayati di dunia. Spesies yang paling umum digunakan untuk pengendalian biologis adalah T. atopovirilia, T. brevicapillum, T. Deion, T. exiguum, T. fuentesi, T. minutum, T. nubilale, T. platneri, T. pretiosum, dan T. thalense.
Wanita dewasa menggunakan sinyal kimia dan visual, seperti bentuk telur dan warna, untuk mencari telur dalam tanaman.  Ketika telur yang cocok ditemukan betina akan menggunakan antennal drum untuk menentukan ukuran suatu kesesuaian telur. Tergantung pada ukuran dan kualitas telur target, perempuan akan mengebor terus ke dalam chorion dan masukkan jumlah yang sesuai telur. Seorang perempuan tunggal dapat parasitize 1-10 telur sehari.
Trichogramma kecil dan sangat seragam di alam yang menyebabkan kesulitan dalam mengidentifikasi spesies yang terpisah. Karena perempuan semua relatif sama itu selalu jatuh pada laki-laki untuk memberitahu spesies yang berbeda terpisah dengan memeriksa antena mereka dan alat kelamin. Saat ini jumlah spesies Trichogramma mendekati 200 namun sebelumnya pada tahun 1960 hal itu dianggap hanya enam spesies Trichogramma ada.
Gambaran pertama dari spesies Trichogramma berada di Amerika Utara pada tahun 1871 oleh Charles V. Riley. Dia menggambarkan tawon kecil yang muncul dari telur kupu-kupu Viceroy sebagai Trichogramma minutum. Dalam entomologi, spesimen asli sangat penting karena mereka adalah dasar acuan untuk deskripsi selanjutnya spesies. Spesimen asli, bagaimanapun, telah hilang.
Riley juga menggambarkan sebuah spesies kedua pada tahun 1879 sebagai Trichogramma pretiosum, tetapi spesimen hilang juga. Akibatnya, ahli taksonomi harus bergantung pada deskripsi tertulis dari spesimen asli. Ini kemungkinan besar telah berkontribusi pada kesulitan dalam memisahkan Trichogramma morfologis mirip genera.
Untuk memperbaiki kesalahan ini, ahli entomologi kembali ke daerah-daerah di mana Riley awalnya menemukan spesies dan memperoleh spesimen neotype T. minutum dan T. pretiosum. Spesimen ini sekarang diawetkan dengan baik di Amerika Serikat National Museum.Trichogramma telah digunakan untuk mengendalikan hama Lepidoptera selama bertahun-tahun. Mereka dapat dianggap sebagai Drosophila dari dunia parasitoid karena mereka telah digunakan untuk rilis inundative dan banyak dari pemahaman kita saat ini berasal dari percobaan dengan tawon.
Ahli entomologi di awal 1900-an mulai membesarkan Trichogramma untuk pengendalian biologis. Trichogramma minutum adalah salah satu spesies yang paling umum ditemukan di Eropa dan massa pertama dibesarkan pada tahun 1926 pada telur dari Sitotroga cerealella.
Sembilan spesies Trichogramma diproduksi secara komersial di insectaries di seluruh dunia dengan 30 negara mengalami Trichogramma dirilis di dalamnya. Trichogramma digunakan untuk kontrol pada tanaman banyak dan tanaman, ini termasuk kapas, tebu, sayuran, gula bit, kebun dan hutan. Beberapa hama yang dikendalikan meliputi Cotton bollworm (Helicoverpa armigera), Codling ngengat (Cydia pomonella), LightBrown apple ngengat (Epiphyas postvittana), dan Eropa penggerek batang jagung (Ostrinia nubilalis).
Spesies Trichogramma bervariasi dalam spesifisitas inang mereka. Hal ini dapat menyebabkan non-target host yang terparasit. Hal ini dapat menyebabkan masalah dengan mengurangi jumlah parasitisme dari host target, dan tergantung pada tingkat parasitisme, non-target efek bisa signifikan pada non-target populasi tuan rumah. Ketika memilih Trichogramma untuk pengendalian biologis, penting untuk mencoba untuk memilih host spesies spesifik dan lebih disukai spesies asli dari Trichogramma.
Spesies
Trichogramma pretiosum adalah spesies Trichogramma paling banyak didistribusikan di Amerika Utara. Ini telah menjadi fokus dari studi penelitian banyak dan telah mampu untuk dipelihara pada 18 genera Lepidoptera. Ini isa parasitoid lebih umum, dimana kemungkinan untuk parasitise berbagai spesies yang berbeda. Trichogramma pretiosum (Riley) diperkenalkan ke Australia pada tahun 1970 sebagai bagian dari Daerah Irigasi Sungai Ord (ORIA) IPM skema. Trichogramma pretiosum awalnya digunakan untuk menggambarkan Trichogramma dari host non-arboreal tanaman seperti kapas.
Trichogramma carverae terutama digunakan untuk cahaya ngengat apel coklat dan kontrol memanjakan ngengat dan didominasi digunakan di kebun. Di Australia T. carverae digunakan untuk kontrol biologis coklat apel ngengat di kebun-kebun anggur. Meskipun Australia memiliki spesies alaminya Trichogramma belum ada banyak pekerjaan dilakukan untuk menggunakannya secara komersial untuk pengendalian biologis di Australia. Light brown apple moth umum di seluruh Australia dan polifag pada lebih dari 80 spesies asli dan diperkenalkan. Larva adalah tahap yang menyebabkan kerusakan paling, terutama untuk anggur beri yang menyediakan situs untuk membusuk sekelompok terjadi. Kerugian dalam tanaman dapat berjumlah sampai $ 2000 / ha dalam satu musim. Hal ini sangat dominan di daerah-daerah seperti Yarra Valley. Penggunaan insektisida bukanlah metode yang disukai oleh kebanyakan petani yang lebih memilih rata-rata lebih alami mengendalikan hama. Akibatnya, Trichogramma dianggap calon yang baik untuk pengendalian biologis sebagai larva sulit untuk mengontrol dengan insektisida dan cokelat muda apple ngengat relatif rentan terhadap parasit telur dengan telur mereka yang diletakkan di massa 20-50 pada permukaan atas basal daun dalam anggur.

Parasitoids Trichogramma

Trichogramma are minute polyphagous wasps, commonly known as ‘stingless wasps’, that are endoparasitoids of insect eggs. Endoparasitoids lay their eggs in eggs or larvae of other species. Currently in the world there is an estimated 50 million animal species with 1.7 million having been described. Of these, seventy-five per cent are believed to be insects. Trichogramma represent around 80 genera from the Trichogrammatidae family with over 800 species worldwide.

Members of the Trichogrammatidae family range in size from 0.2 to 1.5 mm. Key means of dispersal include walking and short jumps.  The adults require sugar as an energy source obtained from nectars, honeydew, plant sap and sugars leached through the phloem. They occur naturally in a variety of habitats across the world and have the ability to parasitize numerous host species. Their main hosts are eggs of Lepidoptera and other species such as Hymenoptera, Neuroptera, Diptera, Coleoptera and Hemiptera.

Although there are several egg parasitoids commonly used throughout the world, Trichogramma have been the most extensively studied.  There have been more than a thousand papers published on Trichogramma and they are the most used biological control agents in the world.  The most commonly used species for biological control are T. atopovirilia, T. brevicapillum, T. deion, T. exiguum, T. fuentesi, T. minutum, T. nubilale, T. platneri, T. pretiosum, and T. thalense.

Female adults use chemical and visual signals, such as eggs shape and colour, to locate eggs within a crop. [3] When a suitable egg is found the female will use antennal drumming to determine the size an suitability of the egg. Depending on the size and quality of the target egg, the female will drill a hold into the chorion and insert an appropriate number of eggs. A single female can parasitize one to ten eggs a day.

Trichogramma are small and very uniform in nature which causes difficulty in identifying the separate species.  As females are all relatively similar it has always fallen upon the males to tell the different species apart by examining their antennae and genitalia.  Currently the number of Trichogramma species is approaching 200 but previously in 1960 it was thought only six species of Trichogramma existed.

The first description of a Trichogramma species was in North America in 1871 by Charles V. Riley. He described the tiny wasps that emerged from eggs of the Viceroy butterfly as Trichogramma minutum.  In entomology, original specimens are very important as they are the basis of reference for subsequent descriptions of species. The original specimens, however, were lost.

Riley also described a second species in 1879 as Trichogramma pretiosum, but these specimens were lost too. As a result, taxonomists must rely on written descriptions of these original specimens. This most likely has contributed to the difficulty in separating the morphologically similar Trichogramma genera.

To correct these errors, entomologists returned to the areas where Riley originally found the species and obtained neotype specimens of T. minutum and T. pretiosum. These specimens are now preserved properly in the United States National Museum.
Trichogramma have been used for control of lepidopteran pests for many years. They can be considered the Drosophila of the parasitoid world as they have been used for inundative releases and much of our understanding today comes from experiments with these wasps.

Entomologists in the early 1900’s began to rear Trichogramma for biological control. Trichogramma minutum is one of the most commonly found species in Europe and was first mass reared in 1926 on eggs of Sitotroga cerealella.

Nine species of Trichogramma are produced commercially in insectaries around the world with 30 countries experiencing Trichogramma released in them. Trichogramma are used for control on numerous crops and plants, these include cotton, sugarcane, vegetables, sugar beets, orchards and forests.  Some of the pests that are controlled include Cotton bollworm (Helicoverpa armigera), Codling moth (Cydia pomonella), Lightbrown apple moth (Epiphyas postvittana), and European corn borer (Ostrinia nubilalis).

Trichogramma species vary in their host specificity. This can lead to non-target hosts being parasitized. This can cause problems by reducing the amount of parasitism of the target host, and depending on the rate of parasitism, non-target effects could be significant on non-target host populations. When picking Trichogramma for biological control, it is important to try to choose a host specific species and preferably a native species of Trichogramma.

Spesies

Trichogramma pretiosum is the most widely distributed Trichogramma species in North America.  It has been the focus of many research studies and has been able to be reared on 18 genera of Lepidoptera. It isa more general parasitoid, by which it is likely to parasitise a range of different species. Trichogramma pretiosum (Riley) was introduced into Australia in the 1970s as part of the Ord River Irrigation Area (ORIA) IPM scheme. Trichogramma pretiosum was originally used to describe Trichogramma from hosts on non-arboreal plants such as cotton.

Trichogramma carverae are mainly used for light brown apple moth and coddling moth control and is predominately used in orchards. In Australia T. carverae is used for biological control of light brown apple moth in vineyards. Though Australia has its own native Trichogramma species there has not been much work undertaken to commercially use them for biological control within Australia. Light brown apple moth is common throughout Australia and is polyphagous on more than 80 native and introduced species. The larvae are the stage that causes the most damage, especially to grape berries which provides sites for bunch rot to occur. Losses in the crops can amount up to $2000/ ha in one season. It is very predominant in areas like the Yarra Valley. Insecticide use is not a preferred method by most growers who prefer a more natural mean of controlling pests. As a result, Trichogramma were considered a good candidate for biological control as the larvae are difficult to control with insecticide and light brown apple moths are relatively vulnerable to egg parasitism with their eggs being laid in masses of 20-50 on the upper surfaces of basal leaves in grapevines.

Contoh Referensi Parasitoid Trichogrammatidae

Karakter morfologi parasitoid trichogramma chilotraeae
nagaraja dan nagarkatti (hymenoptera:
trichogrammatidae): 
Salah satu parasitoid telur hama
plutella xylostella L.
 

Pengarang :
Sumber : AgriSains : jurnal ilmiah
Penerbit : Universitas Tadulako. Fakultas Pertanian
Kode Panggil : 630.5 Agr s
Tahun Terbit Artikel: 2007
Volume : 8
No : 2
Halaman : 76-82
Kata Kunci : Parasitoids; Plutella xylostella; Trichogramma
chilotraceae; Biological control agents
Sari :
Penelitian ini bertujuan untuk menganalisis karakter
morfologi parasitoid Trichogramma chilotraeae
Nagaraja dan Nagarkatti. Parasitoid ini merupakan salah
satu parasitoid yang menyerang telur hama Plutella
xylostella pada tanarnan kubis. Analisis karakter
morfologi didasarkam pada karakter antena imago
jantan, karakter sayap depan dan ciri khas alat genitalia
imago jantan. Parasitoid T. chilatraeae ini mempunyai
karakter antena dimana pada bagian club tidak
bersegmen dengan rambut yang panjang, Sayap depan
mempunyai setae yang letaknya tersusun dalam suatu
barisan, mempunyai 3-4 setae pada Rsl dan fringe satae
yang barukuran lebih pendek. Alat genitalia imago
jantan mempunyai dorsal expansion gonobase yang
berbentuk segitiga dengan ujung yung runcing, chelat
structure yang besar dan terletak jauh dari ujung
gonoforceps, mempunyai aedagus yang panjang dan
runcing.

Abstrak :
The aim of study was to analyze morphological
characteristics of parasitoid Trichogramma chilotraeae.
This parasitoid is one of various parasitoid that
attacking Plutella xylostella eggs. To determine the
morphological characteristics af T. chilatraeae, the
study was based on antennal of male, forewings and
genitalia. The result of study found that morphological
characteristics of Z. chilotraeae were unsegmented
antennal with long hairs, forewings have 3-4 sctac RSl.
The male genitalia has a dorsal axpansion gonobase
(DEG) that was formed triangular with the top of
genitalia was tapering. The position of chelat structure
is far form the top gonoforceps with long and taperingaedagus.

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