Uscana lariophaga, West-African egg parasitoid of the cowpea bruchid beetle Callosobruchus maculatus: photoperiod, parasitization and eclosion interactions

AbstractThe performance of the egg parasitoidUscana lariophagaSteffan was studied when reared on eggs of the bruchid storage pest,Callosobruchus maculatus(Fabricius) developing in seeds of cowpea, chickpea and pigeonpea. The beetle laid more and larger eggs on pigeonpea than on cowpea and chickpea, indicating that there was not a trade-off between number and size of the eggs. The bruchid larvae reared on pigeonpea exhibited a longer development time and a higher mortality than those reared on cowpea and chickpea. The resulting males weighed less than those reared on cowpea and chickpea. The trichogrammatidU. lariophagaparasitized more eggs whenC. maculatuswas reared on chickpea than when reared on the other hosts. Parasitoid larvae developed slowest and had the highest mortality in eggs ofC. maculatusreared on pigeonpea compared to those reared on cowpea and chickpea; the sex ratio (% of females) of the resulting adults was also higher. The high mortality and long development time ofC. maculatusreared on pigeonpea indicated that this legume was less favourable toC. maculatusthan chickpea or cowpea. This was probably also true for the parasitoid since the mortality was higher and development longer in eggs ofC. maculatusreared on pigeonpea compared to those reared on cowpea and chickpea. Therefore, when host eggs were larger and of lower nutritional quality, the proportion of female egg parasitoids was greater.

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Hypoxic environment protects cowpea bruchid (Callosobruchus maculatus) from electron beam irradiation damage

Pest Management Science ◽

10.1002/ps.5172 ◽

2018 ◽

Vol 75 (3) ◽

pp. 726-735 ◽

Cited By ~ 4

Author(s):

Lei Wang ◽

Weining Cheng ◽

Jia Meng ◽

Mickey Speakmon ◽

Jiangping Qiu ◽

...

Keyword(s):

Electron Beam ◽

Electron Beam Irradiation ◽

Callosobruchus Maculatus ◽

Irradiation Damage ◽

Beam Irradiation ◽

Hypoxic Environment ◽

Cowpea Bruchid

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Use of Microwave Heating Technology for Disinfestation of Stored Green Gram (Vigna radiata) against Cowpea Bruchid Callosobruchus maculatus (Fabricius)

Legume Research - An International Journal ◽

10.18805/lr-4653 ◽

2021 ◽

Author(s):

R. Kooner ◽

D.K. Sharma ◽

K.S. Suri

Keyword(s):

Callosobruchus Maculatus ◽

Pupal Stage ◽

Exposure Period ◽

Green Gram ◽

Life Stages ◽

Chemical Methods ◽

Cowpea Weevil ◽

Alternative Approach ◽

Cowpea Bruchid ◽

Heating Technology

Background: Pulses are an integral component of food in India which acts as major source of protein required for growth and maintenance of body. But during their storage they suffer heavy losses resulting in depletion of their quality and edibility. The present studies focused on disinfestation of green gram grains using microwaves as an alternative approach to chemical methods for controlling insects in grains and pulses. Methods: In this laboratory studies during 2017-18, the grains of green gram were infested with different life stages of the cowpea weevil and exposed to 200, 400, 600 and 800 W microwave power levels, each at an exposure period of 10, 20, 30 and 40 s. Result: Eggs were the most susceptible, while pupal and adults were the least susceptible life stages to microwave treatments. Complete mortality of eggs was achieved with microwave treatments (400, 600 and 800 W), each at an exposure period of 30 and 40 s. Complete inhibition of larval stage was attained with 400 and 600 W (30 and 40 s) and 800 W (20, 30 and 40 s exposure) while for pupal stage it was observed at the higher wattages of 600 (40 s exposure) and 800 (30 and 40 s exposure). Microwave wattage of 600 W for 40 sand 800 W for 30 and 40 s exposure caused 100% mortality of 2d old adults of cowpea bruchid.

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