Qualitative Aspects

The nature of the food available may have striking effects on the survival, rate of growth, and reproductive potential of a species, and much work has been done on insects in this regard. For example, of the insect fauna associated with stored products, the saw-toothed grain beetle, Oryzaephilus surinamensis, can survive only on foods with a high carbohydrate content such as flour, bran, and dried fruit, whereas species of spider beetles, Ptinus spp., and flour beetles, Tribolium spp., have no such carbohydrate requirement and are consequently cosmopolitan, occurring in animal meals and dried yeast, in addition to plant products. For some phytophagous insects, a combination of plants of different kinds appears necessary for survival and/or normal rates ofjuvenile development. In the migratory grasshopper, Melanoplus sanguinipes, for example, a smaller percentage of insects survive from hatching to adulthood, and the development of those that do survive is slower when the grasshoppers are fed on wheat (Triticum aestivum) alone compared with wheat plus flixweed (Descurainia Sophia) or dandelion (Taraxacum officinale) (Pickford, 1962).

Both the rate of egg production and the number of eggs produced may be markedly affected by the nature of the food available. Many common flies, for example, species of Musca, Calliphora, and Lucilia, may survive as adults for some time on a diet of carbohydrate. However, for females to mature eggs a source of protein is essential. Pickford (1962) showed that M. sanguinipes females fed a diet that included wheat and wild mustard (Brassica kaber) or wheat and flixweed produced far more eggs (579 and 467 eggs per female, respectively) than females fed on wheat (243 eggs/?), wild mustard (431 eggs/?), or flixweed (249 eggs/?), alone. These differences in egg production resulted largely from variations in the duration of adult life, though differences in rate of egg production were also evident. For example, percent survival of females fed wheat plus mustard after 1, 2, and 3 months was 93%, 60%, and 13%, respectively. These females produced, on average, 8.4 eggs/female per day. The corresponding figures for females fed on wheat alone were 87%, 27%, and 0% survival over 1, 2, and 3 months, respectively, and 4.6 eggs/female per day. The metabolic basis for these differences was not determined.

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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