Table 2 Effects of Climatic Factors on the Abundance of M. sorbens, Moderate Quality Studies (from Hafez and Attia, 1958 [22])

Authors: Hafez and Attia, 1958 [22]

Temperature

Egg incubation period

Humidity maintained at 100 % RH. Between 53 and 60 eggs were studied at 5.5 °C, 16 °C, 24 °C, 28 °C, 32 °C, 36 °C, 40 °C and 43 °C.

Eggs failed to hatch at 5.5 °C or 43 °C . Eggs took an average of 5.28 h to hatch at 40 °C and 25.3 h at 16 °C.

Within temperature limits that permitted hatching, incubation period was inversely proportional to temperature. Optimal hatching occurred at 28C. No statistical measures.

Type: Lab study

Location: Taliba, Egypt.

Egg hatching percentage

Eggs were fertile and secured from copulated females.

At 16 °C 95 % of eggs hatched. At 28 °C 100 % of eggs hatched. At 36 °C 90 % of eggs At 40 °C 65 % of eggs hatched.

Larvae Duration of larval period

Larvae were reared on 15 g milk/bran larval diet, 10 eggs in each 10 cc tube. They were then emptied onto a drier pupation medium.

At 16 °C the mean duration of the larval period was 268.95 ± 0.94 h. At 40C it was 73.05 ± 0.71 h.

Larval period duration was inversely proportional to temperature. Failure to provide drier pupation medium prolonged the larval period duration by several days. No statistical measures.

Pupae Duration of pupal period

Humidity maintained at 70 % RH. 42–58 pupae were studied at temperatures of 16 °C, 24 °C, 28 °C, 32 °C, 36 °C and 40 °C.

At 16 °C the mean duration of the pupal period was 14.9 ± 0.2 h. At 36 °C it was 3.86 ± 0.02 h.

Pupal period duration was inversely proportional to temperature.

Adult Percentage adult emergence

Humidity maintained at 70 % RH. 90–115 pupae were studied at temperatures of 16 °C, 24 °C, 28 °C, 32 °C, 36 °C and 40 °C.

66.6 % of adults emerged at 16 °C. 94.7 % emerged at 24 °C and 28 °C.90 % emerged at 32 °C. None emerged at 40 °C.

Maximum emergence occurred between 24C and 28C. 40C temperatures prevent emergence. No statistical measures.

Authors: Hafez and Attia, 1958 [22]

Relative Humidity

Egg incubation period

Temperature maintained at 31–32 °C. No information given on numbers used.

At 100 % humidity eggs took 6.3–6.6 h to hatch. At 95 % humidity eggs took 6.6–7.1 h to hatch. At 90 % humidity eggs took 7.1–6.6 h to hatch. At 85 % humidity no eggs hatched.

Eggs did not hatch at humidities below 85 %, and took longer to hatch at lower humidities. Fewer eggs hatched at lower humidities. Low humidities damaged eggs through dehydration, causing shrinkage. No statistical measures.

Type: Lab study

Location: Taliba, Egypt.

Egg hatching percentage

Temperature maintained at 31–32 °C. No information given on numbers used.

At 100 % humidity 100 % of eggs hatched. At 90 % humidity 58 % of eggs hatched. At 85 % humidity no eggs hatched.

Egg structure

Fertile eggs laid within 15 min of the start of the experiment were placed in a desiccator.

Egg length/width: When RH was increased from 0 to 100 % length increased from 1.369 mm to 1.465 mm (average elongation 7 %) and width increased from 0.298 mm to 0.312 mm (average increase in width of 4.7 %).

Egg weight (water loss): When exposed to 30 % RH, eggs lost 30 % of their weight in first 60 min (20 % in first 30 min, 10 % in last 30 min). Water loss decreased with increasing exposure to low RH.

Pupae Duration of pupal period

Temperatures of 28⁰ and 36⁰ %.

The pupal phase lasted 106–118 h at 28 °C regardless of humidity, and between 90 and 93 h at 36 °C regardless of humidity.

Relative humidity has no significant effect on duration of the pupal phase.

No information given on numbers used.