Ⅰ. INTRODUCTION The prothoracic gland (PG) is one of the most vital endocrine organs in insects. It is the target organ of prothoracotropic hormone (PTTH) secreted by the neurosecretory cells of the brain. Some inves...Ⅰ. INTRODUCTION The prothoracic gland (PG) is one of the most vital endocrine organs in insects. It is the target organ of prothoracotropic hormone (PTTH) secreted by the neurosecretory cells of the brain. Some investigators have shown that the prothoracic gland is the展开更多
Juvenile hormone plays an important role in controlling the processes of metamorphosis and reproduction of most insects. There has been a growing amount of research works on the determination of JH titers at various p...Juvenile hormone plays an important role in controlling the processes of metamorphosis and reproduction of most insects. There has been a growing amount of research works on the determination of JH titers at various physiological levels in a variety of insect species, yet our knowledge concerning JH titer lags behind that of ecdysteroid titer. The reasons are: (ⅰ) JH titers in most insects seem to be generally quite low, and (ⅱ) it is difficult to separate JH from the lipids that are present in rather large quantities and have similarities in chemical and physical properties.展开更多
In some silk production areas of China, artificial synthesized juvenile hormone analogues (JHA), which are sprayed on the surface of the 3rd-day fifth instar larvae, have been utilized to increase silk production in r...In some silk production areas of China, artificial synthesized juvenile hormone analogues (JHA), which are sprayed on the surface of the 3rd-day fifth instar larvae, have been utilized to increase silk production in recent years. The question about why JHA can promote silk production is not clear yet. However, some works show that it is the increase of the proteinase and amylase in the digestion juice of the larvae which have been treated with hormone that accelerates the transformation of展开更多
The descriptions of moulting cycles in insect embryos have prompted some authors to examine whether or not embryonic moults were also controlled by the same hormones as larval and pupal moults. Lagueux et al. (1979) i...The descriptions of moulting cycles in insect embryos have prompted some authors to examine whether or not embryonic moults were also controlled by the same hormones as larval and pupal moults. Lagueux et al. (1979) indicated that the fluctuations of the titre of free ecdysteroids in the egg during embryonic development of Locusta migratoria展开更多
Ⅰ. INTRODUCTION During the course of ovary development of insect, a layer of vitelline membrane is secreted by follicle cells around an oocyte after the yolk is deposited in the oocyte. Then, the oocyte begins to tak...Ⅰ. INTRODUCTION During the course of ovary development of insect, a layer of vitelline membrane is secreted by follicle cells around an oocyte after the yolk is deposited in the oocyte. Then, the oocyte begins to take up water from hymolymph and its volume gradually expands. Since then, the stage of choriogenesis starts. Chorionins (egg-shell proteins)展开更多
In the studies on the reproduction of the oriental migratory locust (Locusta migratoria manilensis) the authors had observed that the ovary of normally copulated female locusts is an important site of material synthes...In the studies on the reproduction of the oriental migratory locust (Locusta migratoria manilensis) the authors had observed that the ovary of normally copulated female locusts is an important site of material syntheses, but the ovary development of parthenogenetic female locust is so slow that the preoviposition period is greatly prolonged. In recent years we reported that a chemical substance secreted by the male locust possesses the effect of accelerating the ovary development of female locust, in addition to the mechanical stimulating effect of the male in copulating process. Recently a further investigation showed that the ether extracts from the testis, fat body, and abdominal integument of展开更多
基金Project supported by the Science Fund of Academia Sinica
文摘Ⅰ. INTRODUCTION The prothoracic gland (PG) is one of the most vital endocrine organs in insects. It is the target organ of prothoracotropic hormone (PTTH) secreted by the neurosecretory cells of the brain. Some investigators have shown that the prothoracic gland is the
基金Project supported by the National Natural Science Foundation of China.
文摘Juvenile hormone plays an important role in controlling the processes of metamorphosis and reproduction of most insects. There has been a growing amount of research works on the determination of JH titers at various physiological levels in a variety of insect species, yet our knowledge concerning JH titer lags behind that of ecdysteroid titer. The reasons are: (ⅰ) JH titers in most insects seem to be generally quite low, and (ⅱ) it is difficult to separate JH from the lipids that are present in rather large quantities and have similarities in chemical and physical properties.
文摘In some silk production areas of China, artificial synthesized juvenile hormone analogues (JHA), which are sprayed on the surface of the 3rd-day fifth instar larvae, have been utilized to increase silk production in recent years. The question about why JHA can promote silk production is not clear yet. However, some works show that it is the increase of the proteinase and amylase in the digestion juice of the larvae which have been treated with hormone that accelerates the transformation of
文摘The descriptions of moulting cycles in insect embryos have prompted some authors to examine whether or not embryonic moults were also controlled by the same hormones as larval and pupal moults. Lagueux et al. (1979) indicated that the fluctuations of the titre of free ecdysteroids in the egg during embryonic development of Locusta migratoria
文摘Ⅰ. INTRODUCTION During the course of ovary development of insect, a layer of vitelline membrane is secreted by follicle cells around an oocyte after the yolk is deposited in the oocyte. Then, the oocyte begins to take up water from hymolymph and its volume gradually expands. Since then, the stage of choriogenesis starts. Chorionins (egg-shell proteins)
文摘In the studies on the reproduction of the oriental migratory locust (Locusta migratoria manilensis) the authors had observed that the ovary of normally copulated female locusts is an important site of material syntheses, but the ovary development of parthenogenetic female locust is so slow that the preoviposition period is greatly prolonged. In recent years we reported that a chemical substance secreted by the male locust possesses the effect of accelerating the ovary development of female locust, in addition to the mechanical stimulating effect of the male in copulating process. Recently a further investigation showed that the ether extracts from the testis, fat body, and abdominal integument of
