The tomato caterpillar (Heliothis amigera) is mainly a fruit and blossom feeder and has a wide range of food-plants, including maize, sweet corn, linseed, cotton, tobacco, lucerne. tomatoes, beans, peas and the immature fruit of peaches, plums, cherries, and the buds and blossoms of various ornamental garden plants.

During the day the moths are inactive and are hidden amongst the leaves, hut towards the late afternoon they may be seen flying from plant to plant to lay their eggs. The eggs, which are pale yellow, are laid singly, mainly on the blossoms and the young fruit and tender foliage at the top of the plant. They hatch in from three to five days in warm weather, and from six to twelve days under cooler conditions.

The young caterpillars often feed on portions of the tender foliage before attacking the blossoms and fruit. The fully-fed caterpillars, which measure about one and a half inches in length, vary greatly in colour. The caterpillars attain their full size in about fourteen to twenty-one days in warm weather and from three to six weeks under cooler conditions. When fully-fed they burrow into the soil to a depth of about three or four inches and there enter their pupal stage.

The pupal or chrysalis stage may he as short as fourteen days, but in dry or cool weather four or five months may elapse before the moths emerge.

In warm weather the minimum length of the life-cycle from egg to adult is about thirty days, and in mild spring
and autumn weather forty to fifty days. The two main periods of infestation are from mid-September to mid-December, and from February to April.

Moths do not emerge from pupae while the soil is dry. As a result, infestations generally are light during dry summer weather. However, in periods of good summer rainfall, when food-plants are plentiful and soil moisture is favourable to quick emergence of moths, infestations may he widespread.
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