The Reactions of the Desert Locust, Schistocerca gregaria (Forsk.), (Orthoptera, Acrididae) to Physical Factors, with special Reference to Relative Humidity

1957 ◽  
Vol 48 (3) ◽  
pp. 515-531 ◽  
Author(s):  
S. A. Aziz
Keyword(s):  
Relative Humidity ◽  
Light Intensity ◽  
Schistocerca Gregaria ◽  
Fourth Instar ◽  
The Other ◽  
Physical Factors ◽  
Desert Locust ◽  
Level Of Activity ◽  
Enclosed Space ◽  
Very High

Reactions of 3-day-old first- and fourth-instar hoppers of Schistocerca gregaria (Forsk.) of phase gregaria, to three physical factors, namely to relative humidity, temperature and light have been studied in an alternative chamber apparatus designed to give an enclosed space with gradients of humidity. The responses to each factor independent of the others, and to the interactions of these factors, were considered.It was found that both the first- and the fourth-instar hoppers respond strongly to humidity. They are agitated by low, and even more by very high, humidities, but become more quiescent within a zone of 60–70 per cent. R.H., where they spend more time. Within this zone they hop and turn less and this decrease in activity appears to be a response which is independent of both temperature and of light intensity. This zone of decreased agitation has been called “the zone of minimum activity”. However, the speed of walking in contrast to the other types of activity, increased progressively with humidity.Increase in light intensity raises the level of activity at all humidities, i.e., it increases the duration of activity within the limits of experimental time and the speed of walking. With rise in temperature there is an increase in hopping, in klinokinesis and orthokinesis.

Observations on Rate of Growth, Coloration, and the abnormal Six-instar Life-cycle in Locusta migratoria migratorioides, R. &. F.

1936 ◽  
Vol 27 (1) ◽  
pp. 77-85 ◽  
Author(s):  
K. H. L. Key
Keyword(s):  
Life Cycle ◽  
Relative Humidity ◽  
Light Intensity ◽  
Locusta Migratoria ◽  
Fourth Instar ◽  
The Other ◽  
Locusta Migratoria Migratorioides ◽  
The Third ◽  
Rate Of Growth ◽  
Progression Factor

1. All material was reared under constant conditions of temperature, light intensity and relative humidity. Two relative humidities were used—very wet and very dry. In some cases various coloured backgrounds were used. All material was solitaria, and was kept isolated.2. Average weights were calculated from weighings made at all periods within the stadia, and thus represent the weights at the mid-points of the stadia.3. The figures could not be fitted to the theory of a progression factor of 2.4. Females are on the average 50 per cent, heavier than males even in the third instar; the sexes can probably be distinguished in this way much earlier.5. The first three stadia are of about the same length; the fourth is longer, the fifth much longer.6. The percentage rate of growth between the mid-points of successive stadia is of the same order for all pairs, though somewhat lower for the first and last pairs.7. Hoppers kept in a very dry atmosphere are much lighter than those kept wet —proportionally more so in the later than in the earlier instars; on the other hand each stadium is lengthened—proportionally more so in the earlier than in the later stadia; the percentage rate of growth is just half that of hoppers kept wet.8. The findings of Faure in regard to the causes of differences in coloration were fully confirmed.9. The occurrence of a sixth instar in the females is due to an inherited factor.10. This “ extra ” instar may represent an extra morphological third instar or an extra morphological fourth instar.

NOTES ON THE EFFECTS OF PHYSICAL FACTORS ON THE SPRUCE BUDWORM, CHORISTONEURA FUMIFERANA (CLEM.)

1947 ◽  
Vol 79 (11-12) ◽  
pp. 195-195 ◽  
Author(s):  
W. G. Wellington ◽  
W. R. Henson
Keyword(s):  
Light Intensity ◽  
Choristoneura Fumiferana ◽  
Spruce Budworm ◽  
The Other ◽  
Negative Response ◽  
Physical Factors ◽  
Light Traps ◽  
Compass Orientation ◽  
Orderly Transition

Concerning the light reactions of the adults, it may be noted that males are photopositive when in a dark-adapted state, but they rapidly become adapted to any light intensity and become extremely sluggish. Females in the dark-adapted state exbihit either photonegative behaviour or compassing behaviour, with no evidence that there is any orderly transition from one type of behaviour to the other. Light-compass orientation of flying females makes it possible to collect some at light traps, despite their normally negative response.

A Note on the Use of Dried Poison Bait against Locusts in the Sudan

1929 ◽  
Vol 20 (1) ◽  
pp. 99-101 ◽  
Author(s):  
Harold H. King
Keyword(s):  
Red Sea ◽  
Rainy Season ◽  
Arid Regions ◽  
Schistocerca Gregaria ◽  
Locusta Migratoria ◽  
Extended Period ◽  
The Other ◽  
Desert Locust ◽  
The Arid Regions ◽  
Species Being

There are in the Sudan three species of migratory locusts : Anacridium moestum melanorhodon, Walk., or the tree locust, Locusta migratoria, L., and Schistocerca gregaria, Forsk., sometimes termed the desert locust. Of these the last-named is the plague locust of the country—the other two species being relatively unimportant—and is the species referred to as the “ locust ” throughout this paper.From 1899 till 1917 swarms of locusts occurred annually, but then followed a period of ten years during which the Sudan suffered no damage from this pest. In 1927 and again in the succeeding year the locust reappeared as a plague, and there is little doubt but that it is to be expected year by year over an extended period and until the cycle either naturally terminates or is artificially brought to an end. The swarms of fliers appear from May onwards and oviposit in July and August when and where in the arid regions sufficient rain has fallen, the resulting generation of adults emigrating in October. A certain amount of breeding takes place during the winter on the Red Sea littoral, where winter rains occur, but this district is relatively small and easily dealt with ; the main problem is how to prevent breeding during the summer rainy season throughout the vast areas of the central and northern Sudan.

The diurnal activity of the chicken-biting black fly, Simulium griseicolle Becker (Diptera, Simuliidae) in Northern Sudan

1976 ◽  
Vol 66 (3) ◽  
pp. 481-487 ◽  
Author(s):  
S. El Bashir ◽  
M. H. El Jack ◽  
H. M. El Hadi
Keyword(s):  
Wind Speed ◽  
Relative Humidity ◽  
Light Intensity ◽  
Early Morning ◽  
The Other ◽  
Diurnal Activity ◽  
Black Fly ◽  
Early Afternoon ◽  
Trapping Methods ◽  
Two Peaks

AbstractThe diurnal flight activity of Simulium griseicolle Becker was determined at Shambat, Khartoum, by means of a suction trap and a vehicle-mounted trap; and the biting activity by means of a chicken-baited trap. Only incidental observations of mammal-biting activity were made. The three trapping methods indicated two peaks of activity, one in the morning and the other late in the afternoon. Fly activity was lowest in the early afternoon when temperature and light intensity were highest, wind speed was moderate and relative humidity was least. Females outnumbered males in all the catches, except in the early morning when more males were sometimes recorded.

scholarly journals Karakteristik Iklim Mikro Dan Produksi Jagung Manis Pada Beberapa Sistem Tanam

2017 ◽  
Vol 16 (2) ◽  
Author(s):  
Risa Wentasari ◽  
Rizka Novi Sesanti
Keyword(s):  
Relative Humidity ◽  
Light Intensity ◽  
Sweet Corn ◽  
Cropping Systems ◽  
Block Design ◽  
Light Interception ◽  
The Other ◽  
Randomized Block Design ◽  
Significant Difference ◽  
Planting System

The purpose of this study was to determine the characteristics of the micro-climate(temperature, humidity, and light intensity) and the production of sweet corn on a sigle row,doble row, twin row, and Twin seed planting system. This study was conducted in anexperimental garden of Politeknik Negeri Lampung, Hajimena South Lampung, in July-September, 2015. This study is based on randomized block design with one factor croppingsystem consists of 4 treatment ie : Sigle Row (SR) (20cm x 75cm), Doble Row ( DR ) (20cm x20cm x 80 cm), Twin Row (TR) (20cm x 10cm x 80 cm) , and Twin Seed (TS) with plantSpacing (40cm x 75cm 2 seed in one planting hole). Parameter observations of this studyconsisted of (1) micro-climate (temperature (oC), relative humidity (RH %) and Interceptionof Light (%) ) and (2)production (corn length (cm) , corn diameter (m ) and Corn weights(grams). The data were analyzed using the F test at 1 % and 5 % level and than followed bytest BNT. The conclusion of this study were (1) The characteristics of the microclimate : a)There is a noticeable difference in the temperature of the top of the current crop of 4 mst andat 9 mst there is a significant difference in the temperature of the bottom , where SR has adifferent temperature involves the other b) All systems planting has a relative humidity (%)were not significantly different , and c ) there is a difference light interception ( % ) duringthe day when 4 mst , where the twins seed has a light interception is different from othertreatments and there is a difference light interception during 9 mst where sigle row has adifferent light interception to other treatments. (2) The production of sweet corn on thetreatment SR, DR, TR and TS were not significantly different and has a weight of corn (SR =354.8 grams, DR = 316.5 grams, 328.5 grams TR and TS = 325.4 grams) same withdescription bonanza varieties (270-300 grams).Keywords : Cropping Systems , Micro Climate , Production

Transpiration Through the Slifer'S Patches of Acrididae (orthoptera)

1968 ◽  
Vol 48 (2) ◽  
pp. 247-263
Author(s):  
P. MAKINGS
Keyword(s):  
Transpiration Rate ◽  
Room Temperature ◽  
Schistocerca Gregaria ◽  
Cooling System ◽  
Desert Locust ◽  
High Permeability ◽  
Transition Effect ◽  
Structural Peculiarities ◽  
The Difference ◽  
Very High

1. Transpiration through the Slifer's patches of the desert locust (Schistocerca gregaria) was demonstrated experimentally, and was found to be greater than that through the normal cuticle at room temperature (20° C). The difference increases at higher temperatures. Similar results were obtained with other acridids. Death of the animal appeared to have no effect on the phenomenon. 2. Tentative estimations of the patch transpiration rate gave very high values, probably exaggerated by pinhole diffusion. The surprising figure of 169±52mg./cm.2/hr. at about 45° C. was obtained with living preparations. With dead ones and a different method, the values were smaller, being near-zero below 40°C but increasing fairly steeply from 45° to 60° C. 3. It is suggested that the patches might show a transition effect at 40° C. Some superficial lipid which appears to melt at 45° C. all over the cuticle may be connected with the high permeability of the patches. 4. The structural peculiarities of the patches can be explained as adaptations to a high transpiration rate. The patches may form an emergency cooling system, but other functions are not excluded.

Observations on the laboratory take-off behaviour of the desert locust, Schistocerca gregaria (Forskål) (Orthoptera: Acrididae)

1981 ◽  
Vol 71 (3) ◽  
pp. 481-498 ◽  
Author(s):  
M. R. K. Lambert
Keyword(s):  
Wind Speed ◽  
Wind Tunnel ◽  
Light Intensity ◽  
Air Temperature ◽  
Schistocerca Gregaria ◽  
Time Of Day ◽  
Field Observations ◽  
Desert Locust ◽  
Wind Speeds ◽  
Air Temperatures

AbstractObservations were made on crowded, laboratory-reared. 18–20-day-old males of Schistocerca gregaria (Forsk.) taking off in a wind tunnel. Depending upon the time of day, take-off, which was usually upwind, particularly at higher wind speeds, was related to food availability. Few locusts with full foreguts took off, especially at low air temperatures (20°C), while at high temperatures (35°C), 95% of ones starved for 6 h took off. At 30°C, there was little further increase with starvation for 24–30 h. Females containing large oocytes took off less readily than those with small ones. Take-off was also sometimes initiated by decreases in wind speed and light intensity, and sudden changes in air temperature. A distinct passing shadow stimulated take-off, but not the flickering shadows of other flying locusts. A period of flight immediately beforehand inhibited take-off. The results are discussed in relation to field observations.

Thrombotic Thrombocytopenic Purpura: Mechanism for Effectiveness of Plasmapheresis

1979 ◽  
Author(s):  
J. G. Kelton ◽  
P. B. Neame ◽  
I. Walker ◽  
A. G. Turpie ◽  
J. McBride ◽  
...  
Keyword(s):  
Platelet Count ◽  
Thrombotic Thrombocytopenic Purpura ◽  
The Other ◽  
Unknown Etiology ◽  
Normal Range ◽  
Antiplatelet Antibody ◽  
Thrombocytopenic Purpura ◽  
Serious Illness ◽  
Normal Platelet ◽  
Very High

Thrombotic thrombocytopenic purpura (TTP) is a rare but serious illness of unknown etiology. Treatment by plasmapheresis has been reported to be effective but the mechanism for benefit is unknown. We have investigated the effect of plasmapheresis in 2 patients with TTP by quantitating platelet associated IgG (PAIgG) levels prior to and following plasmapheresis. Both patients had very high levels of PAIgG at presentation (90 and A8 fg IgG/platelet respectively, normal 0-5). in both, the PAIgG levels progressively fell to within the normal range and the platelet count rose following plasmapheresis. One patient remained in remission with normal platelet counts and PAIgG levels. The other relapsed after plasmapheresis and the PAIgG level rose prior to the fall in platelet count. Plasmapheresis was repeated and resulted in normalization of both the platelet count and PAIgG level. It is suggested that plasmapheresis removes antiplatelet antibody or immune complexes which may be of etiological importance in this illness.

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