Life History and Habits

Homopterans and the majority of Heteroptera are terrestrial insects. Other Heteroptera show varying degrees of adaptation to an aquatic existence. Some occur in the littoral or intertidal zone of the seashore, on marshy ground, or in damp moss. Others live on the surface of water. Among the truly aquatic forms there is a range of adaptation from those species that must periodically visit the surface to respire (and which periodically fly from one location to another) to those that remain submerged permanently and respire by means of a plastron (see Chapter 15, Section 4.2).

All homopterans and many Heteroptera feed on fluids from plants. All parts of the plant are attacked: roots, stem, leaves, flowers, and seeds (often when these have fallen to the ground). Sternorrhyncha and Fulgoroidea principally feed in phloem, Cicadoidea and Cercopoidea in xylem, and Heteroptera in parenchyma, while Cicadelloidea vary in their choice of tissue (Carver et al., 1991; Novotny and Wilson, 1997). The remaining Heteroptera are predaceous, living on the body fluids of other arthropods and vertebrates. It is primarily because of these feeding habits, assisted in many cases by extraordinarily high rates of reproduction (see Superfamily Aphidoidea), that the order is considered by many people to be the most economically important insect group. The damaging effect on plants may be direct or indirect. When insect populations are large, the loss of sap results in stunted growth and poor yield and quality. Many species, when feeding, inject saliva that causes necrosis of plant tissue. Indirectly, the effects are to weaken the plant, making it more susceptible to attack by other pathogens, especially fungi and viruses. Most important of all, however, is the role of Hemiptera (especially aphids) as vectors of viruses that cause major plant diseases, for example, mosaic, leaf roll, yellows. Among the predaceous Hemiptera, a few species may act as vectors for the transmission of disease; for example, certain South American Reduviidae are carriers of Trypanosoma cruzi, a flagellate protozoan that causes trypanosomiasis (Chagas' disease), a form of sleeping sickness among humans. On the beneficial side, many homopterans play an important part in weed control; for example, Dactylopius species have been successfully used in the control of the prickly pear cactus (Opuntia), and many predaceous Heteroptera exert a major controlling effect on some arthropod pests.

The majority of Hemiptera are bisexual and oviparous. There are, however, species that are facultatively parthenogenetic, and some that are ovoviviparous or viviparous. In many aphids all of these reproductive conditions may be met within the same species in the course of a year. In aphids parthenogenesis and viviparity commonly occur together in the spring and early summer, thus enabling the insects to exploit fully the increased food available at this time. Insemination is typically of the usual intragenital type. However, in Cimicoidea various forms of hemocoelic insemination occur (see Chapter 19, Section

Beekeeping for Beginners

Beekeeping for Beginners

The information in this book is useful to anyone wanting to start beekeeping as a hobby or a business. It was written for beginners. Those who have never looked into beekeeping, may not understand the meaning of the terminology used by people in the industry. We have tried to overcome the problem by giving explanations. We want you to be able to use this book as a guide in to beekeeping.

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