The Control of Reproduction in Diploptera Punctata (Blattaria)

Control of corpus allatum activity during the imaginai diapause in females ofLocusta migratoriaL

“…Diapause was correlated with the activity of few CA cells and low JH levels. Inhibition of the CA by the brain is well known in insect species, e.g., Leucophaea [ 17], Diploptera [ 6,7] [18][19][20], Locusta Kasalinsk strain [4], Eurygaster [21], Manduca (22] and Tetrix undulata [23]. In our results, CA disconnection or NCCII section induced oocyte maturation in 3-wk-old diapausing females.…”

“…In Orthoptera such as Locusta ovarian growth and vitellogenesis are well known to be regulated by juvenile hormone (JH) and brain neurosecretion. In most species, imaginal diapause is correlated with the inactivity of corpora allata (CA) [3][4][5] controlled by the brain via hormonal [5] or neuronal pathways [6,7].…”

Ovarian activation in Melipona quadrifasciata queens triggered by mating plug stimulation (Hymenoptera, Apidae)

“…The pressure exerted by the genitalia valves onto the queen's genital chamber walls could provide the necessary stimulus, via nervous system, to activate production of juvenile hormone by the corpora allata, as has been demonstrated in other insects. In Diploptera cockroaches, for example, egg maturation is mechanically stimulated through copulation and virgin females develop their ovaries when artificial spermatophores are inserted into their bursa copulatrix; ovarian activation, however, does not occur when the ventral nerve chord is severed prior to mating (Engelmann, 1959).…”

Correlation among corpus allatum volume, cell size, and juvenile hormone biosynthesis in ovariectomized adult Blattella germanica

“…In ovariectomized B. germanica a moderate decline in JH synthesis after CA activation is not accompanied by regression in CA volume [9]. Conversely, the CA of ovariectomized Diplapteru ptincfuta [12,13] and Nalrphoctu cinerea [ 141 do not undergo hypertrophy and they exhibit low activity compared with the respective peak rates of JH biosynthesis in intact adult females.…”