- 期刊
- OpenAccess
Nutritional Physiology of the Brown Planthopper, Nilaparvata lugens Stål (Hemiptera: Delphacidae)
摘要
The effect of sugars on larval growth of N. lugens was examined. The insects were reared on a diet containing 0-50% sucrose as the only sugar. When sucrose was eliminated completely, all the insects died in the 1st instar by the third day after the experiment was started. Insects fed on a diet containing 1% sucrose grew to some extent, but none of then reached the 4th instar. On a diet containing 3% sucrose, a few insects developed into adults, and on diets with more than 3%, and up to 50% sucrose more insects developed into adults. However larvae fed on a diet containing 5% sucrose had the shortest development time and grew the fastest. The greater the concentration of sucrose from 10 to 50%, the longer the development time of N. lugens larvae. When 5% glucose, fructose, trehalose, maltose or raffinose was used in the synthetic diet in place of sucrose, all the insects died in the 1st or 2nd instars. But by adding 1% sucrose to diets containing glucose, fructose or maltose, the hatched larvae developed into adults. All of the incects fed on diets containing trehalose or raffinose died in their 1st instar even when sucrose was supplemented. The amino acids essential for the growth of larvae of N. lugens was examined. The insects were reared on MED-1 diet from which one of the amino acids were eliminated. The insects could grow up to the adult stage in the absence of any one of the 23 amino acids contained in the MED-1 diet. This leads us to consider that the amino acid synthesizing activity of N. lugens is large or that symbiotic microorganism in the insects supply amino acids to N. lugens. However, the insect could not grow on a diet containing no amino acids, suggesting that some amino acid substitutes for the missing amino acid when only one is missing. N. lugens was reared on the synthetic diet MED-1 from which vitamins were eliminated one by one, in order to examine the vitamins essential for the growth of the larvae. The hatched larvae developed into adults when either riboflavin, nicotinic acid, folic acid, inositol, choline chloride, biotin or ascorbic acid was eliminated from the diet. However, all of the insects died before the 3rd instar when they were grown on a diets lacking thiamine, pyridoxine or pantothenic acid. Therefore, these three vitamins were considered to be essential for the growth of N. lugens larvae.