Volume 94, Issue 5
October 1985, pages 443-573
pp 443-461 October 1985
Studies on the host preference in some acridids revealed sequentiaiity of feeding behaviour aided by various sensillae, the suitability of the host plant greatly depending upon the physical and chemical factors. Studies on acridids and pyrgomorphid species indicated thatTruxalis indica feed exclusively on grasses,Orthacris maindroni only on dicot plants andAtractomorpha crenulata on both monocot and dicot plants. Significant variations in the quantitative food intake on diverse host plants during post-embryonic development were also evident. Distribution and density of diverse sensillae on the antennae, iabrum, maxillary and labial palps as well as their role in food selection are documented. The impact of antennal and palpal ablation on host selection, the quantity of food intake as well as the influence of diverse host plants on fecundity are discussed.
pp 463-468 October 1985
The parasitisation ofHeliothis armigera (Hubner) larvae byCampoletis chlorideae Uchida andEnicospilus biconatus Townes, Townes & Gupta (= neorufus Rao & Nikam) was 8·70 and 13·79% respectively during the first generation on pigeonpea during 1983–84 at Parbhani. The parasitisation ofH. armigera by these parasites was low in second overlapping generation. Thus,C. chlorideae andE. biconatus were identified as key mortality factors forH. armigera on pigeonpea.
pp 469-474 October 1985
The transpiration rates and acclimation to water and temperature ofPorcellionides pruinosus Brandt andPorcellio laevis Latreille, the common terrestrial isopods occurring in and around Trivandrum, India, were studied. Transpiration rates in different temperatures (24 to 50°C) were higher in both the species during the first 15 minutes’ exposure when compared to 1-hour duration. Previous acclimation to different humidity and temperature conditions affected the transpiration rates in both the species and lower rates of transpiration occurred in isopods acclimated to dry conditions and higher temperatures. Survival rates improved at lethal temperatures in specimens acclimated to 34° C.
pp 475-480 October 1985
Metabolic effects of eyestalk removal in the fiddler crabsUca annulipes andU. triangularis were studied. Bilateral extirpation of eyestalks results in hypoglycemia and a fall and rise in the glycogen content of hepatopancreas and muscle respectively. Eyestalk removal also caused a fall in protein and fat content of hepatopancreas and muscle respectively. Injection of eyestalk extract restored the level of blood sugar, glycogen, protein and fat to normal level.
pp 481-488 October 1985
The fecundity of an allochthonous feeder,Rasbora daniconius and an autochthonous feeder,Puntius amphibius in a perennial tropical pond was assessed and found to be higher in the latter. The fecundity of each of the species was correlated with parameters like standard length, weight offish, length and weight of ovary. A comparison of the regression coefficients in the relations statistically confirmed that as the length or weight of the fish and the length of the ovary increased the rate of increase in the number of eggs was greater inP. Amphibius suggesting a better assimilation of the autochthonous food byP. amphibius than of the allochthonous food byR. daniconius.
pp 489-501 October 1985
Embryonic development ofDysdercus cingulatus is briefly described. In the embryos, neurosecretory cells become evident in the median, lateral and ventral aspects of protocerebrum 84 hr after egg laying. The corpora cardiaca, the corpora allata and the prothoracic glands arise more or less simultaneously at 78 hr from the dorsolateral wall of the stomodaeum, from the mandibular segments and from the labial segments respectively. Secretory material appears in the brain neurosecretory cells and in the intrinsic cells of the corpus cardiacum at 84 hr and in the nervi corpori cardiaci and aorta at 90 hr. The cells of the prothoracic glands show signs of secretory activity at 90 hr, reaching maximum activity around 96 hr. The corpus allatum appears to be inactive in the embryo. Two embryonic moults appear between 96 hr and 110 hr. Consequence of events suggests that the neurosecretory material stimulates the prothoracic glands including embryonic moulting.
pp 503-508 October 1985
The androgenic gland ofM. lamerrii is situated near the seminal vesicle and along the vas deferens of the male prawns. Histologically it is made up of cords of cells which are arranged loosely. Histochemical analysis of the androgenic gland cells showed the presence of cystine/cysteins, protein bound amino acid groups. Androgenic gland ofM. lamerrii shows signs of increased secretory activity during the sexually active phase of the male. In adult prawns, eyestalk ablation results in the hypertrophy of androgenic gland. Brain and thoracic ganglion extracts also showed enhanced secretory activity of androgenic gland and corresponding gonadal activity in the male prawns.
pp 509-515 October 1985
Insect pests were collected from cultivated and wild plant species to study their parasites in Andhra Pradesh, India. Besides insects, nematodes emerged as parasites WhileHexamermis spp. were common in most lepidoptera,Ovomermis albicans (Siebold) was recovered fromHeliothis spp. The nematodes were active, even more than insect parasites during early monsoon. They were more active on light-soils than on heavy-soils. AgainstHeliothis armigera (Hubner) in particular, their incidence was more on “low-growing” crops likeArachis hypogaea (L.), andLycopersicon esculentum (L.), and weeds. The nematode Pentatomimermis sp. was recorded from the bugNezara viridula L.
pp 517-521 October 1985
Wing microsculpturing has been described in the genusAmitermes. It occurs on the upper and lower wing surfaces and is composed of a single row of small (3–5 μm long), thorny papillae at the anterior margin and numerous micrasters all over the wing membrane (size 6–8 μm×5–7 μm; density 9200–9600/mm2). The micrasters are with 5–8 arms and of the complex type (types V–X). No arrowheads are present. The position ofAmitermes is discussed in the general scheme of termite microsculpturing. Comparison is also made with the condition in the Zoraptera, Embioptera and the Blattoidea.
pp 523-526 October 1985
In the present study the amount of protection offered by the use of S-phenetyl formamidino 4(N-ethyl isothioamide) morpholine dihydrochloride to adrenal gland was investigated on albino rats against two graded doses of x-rays (1500R each). Total body x-irradiation brought about the hypertrophy and degranulation of adrenal cortical and medullary cells. The extent of hypertrophy and degranulation increased after the 2nd exposure to x-rays. Treatment with S-phenetyl formamidino 4(N-ethyl isothioamide) morpholine dihydrochloride prior to each dose of irradiation precluded the radiation changes caused in the adrenal cortex and medulla of the rats.
pp 527-531 October 1985
Liver and muscle succinic dehydrogenase enzyme activity inSarotherodon mossamhicus subjected to sublethal concentrations ofddt and malathion declined significantly when compared to the control. The isoenzyme patterns of serum, liver and muscle m the fishes exposed to toxicants showed marked variations from that of the control. The variations inldh isoenzyme patterns attribute alteration in the oxidative capacity of the tissues. The histological changes in the liver of the experimental group also revealed the harmful effects of ddt and malathion. The results suggest an alteration in the tissue metabolism towards an anaerobic type.
pp 533-545 October 1985
Eggs of Piratinae are unique among reduviids in possessing stellate chorionic filaments that remain exposed even after the insertion of the egg into the ground. These eggs have developed many structures for supplying ambient oxygen to the developing embryo inside them. The ultrastructure of the chorion, the operculum and the aeromicropylar system of the eggs of seven species of piratinae bugs are reported.
pp 547-556 October 1985
An analysis of the host plant relationships with respect to the red pumpkin beetle,Raphidopalpa foveicollis Lucas is presented based on the role of receptors involved in host selection, the quantitative food utilization on different cucurbitaceous host plants and the biochemical parameters involved in food plant selection. Orientation of the beetles towards the host plants appeared to be profoundly affected when the receptors present on the antennae and mouthparts were ablated or coated. Though significant differences were observed with regard to the quantity of food ingested among different host plants, ingestion of food was higher for mature leaves and flowers compared to young and senescent leaves. Accordingly, mature leaves and flowers showed high nitrogen and proteins, low sugars, moderately high phenols and narrowC/N ratio compared to other plant parts. The chemosensory receptors present on the antennae and mouthparts were also studied using scanning electron microscope.
pp 557-566 October 1985
Distribution of earthworms has been studied in four locations comprising of two sandy loam and two clay loam soils of Madras, and correlated with the physical and chemical parameters of the soil.L. mauritii andO. serrata are the dominant earthworm species in the sandy loams and clay loams respectively. Each location has limiting factors like temperature, moisture and/or soil texture which strongly govern the density and diversity of earthworm populations in that region.
pp 567-572 October 1985
The protease activity in the midgut of bivoltine and muitivoltine races of the silkworm,Bombyx mori, was studied. The enzyme activity increased during fifth instar reached a peak, and decreased significantly through pre-pupal stage to the lowest level at the pupal stagTouring pharate adult period, the protease activity increased to reach another peak just before emergence of the moth, and decreased thereafter. The enzyme activity m bivoltmes was about 2–3 times higher than multivoltines at the peak levels. Bivoltines showed a sex difference in midgut protease activity while no significant difference was observed in multivoltines. Larvae and pharate adults showed a difference in the pH optima for the enzyme activity. From the results the possible role of midgut protease during the process of metamorphosis is discussed.
pp 573-573 October 1985