scholarly journals LABORATORY ASSESSMENT OF ENTOMOPATHOGENIC FUNGI Beauveria bassiana (Balsamo) TO CONTROL THE LESSER GRAIN BORER Rhyzopertha dominica (F.) ON WHEAT KERNELS.

2011 ◽  
Vol 2 (2) ◽  
pp. 227-237
Author(s):  
O. El-Sebai
1978 ◽  
Vol 56 (4) ◽  
pp. 624-633 ◽  
Author(s):  
A. Campbell ◽  
R. N. Sinha

The weights and caloric values of insects and exuviae, the food consumed and egested, and oxygen respired were estimated at regular intervals for all stages of the rusty grain beetle, Cryptolestes ferrugineus, reared on wheat kernels. Immature stages assimilated between 66 and 79% of the food consumed and the proportion of assimilated energy converted into tissue growth increased from 3 to 23% during development. Similar observations were made for the lesser grain borer, Rhyzopertha dominica, but the food consumed and egested was not measured because much of the kernel chewed by this insect was not ingested, leaving a frass of white powder difficult to separate from the rejecta. For R. dominica a maximum of 38% of the energy assimilated during development was converted into tissue. Adults of both species used most energy to produce eggs. The net efficiencies of the use of energy for reproduction are higher in some stored-product beetles whose populations increase more rapidly than those which increase more slowly.


2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Besma Hamrouni Assadi ◽  
Sabrine Chouikhi ◽  
Refki Ettaib ◽  
Naima Boughalleb M’hamdi ◽  
Mohamed Sadok Belkadhi

Abstract Background The misuse of chemical insecticides has developed the phenomenon of habituation in the whitefly Bemisia tabaci (Gennadius) causing enormous economic losses under geothermal greenhouses in southern Tunisia. Results In order to develop means of biological control appropriate to the conditions of southern Tunisia, the efficacy of the native strain of the predator Nesidiocoris tenuis Reuter (Hemiptera: Miridae) and two entomopathogenic fungi (EPF) Beauveria bassiana and Lecanicillium muscarium was tested against Bemisia tabaci (Gennadius). Indeed, the introduction of N. tenuis in doses of 1, 2, 3, or 4 nymphs per tobacco plant infested by the whitefly led to highly significant reduction in the population of B. tabaci, than the control devoid of predator. The efficacy of N. tenuis was very high against nymphs and adults of B. tabaci at all doses per plant with a rate of 98%. Likewise, B. bassiana and L. muscarium, compared to an untreated control, showed a very significant efficacy against larvae and adults of B. tabaci. In addition, the number of live nymphs of N. tenuis treated directly or introduced on nymphs of B. tabaci treated with the EPF remained relatively high, exceeding 24.8 nymphs per cage compared to the control (28.6). Conclusions It can be concluded that the native strain of N. tenuis and the EPF tested separately were effective against B. tabaci. Their combined use appears to be possible.


2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Muhammad Shehzad ◽  
Muhammad Tariq ◽  
Tariq Mukhtar ◽  
Asim Gulzar

Abstract Background The diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), is a noxious pest of cruciferous crops all over the world causing serious economic damage. Management of insect pest generally depends on chemical control; however, due to development of resistance against all types of insecticides, alternative approaches especially utilization of a microbial agent is inevitable. Results Potential of 2 entomopathogenic fungi (EPF), viz., Beauveria bassiana and Metarhizium anisopliae, was evaluated against 2nd and 3rd larval instars of P. xylostella by adopting leaf dip and direct spraying methods under laboratory conditions. Significant mortality rate was achieved by each fungus under adopted methodologies. However, B. bassiana was found to be more effective in both conditions than M. anisopliae. Highest mean corrected mortality (77.80%) was recorded, when spores of B. bassiana were sprayed on the 2nd instar larvae (LC50=1.78×104/ml) after the 6th day of treatment. Similarly, incase of M. anisopliae LC50 for the 2nd instar at the same methodology was 2.78×104/ml with a mortality percentage of 70.0%. Offspring sex ratio was non-significantly related to treatment concentration and methodology, except for the control. Conclusion Beauveria bassiana and M. anisopliae had potential to suppress P. xylostella infestations when applied appropriately. Present findings suggested that B. bassiana and M. anisopliae when sprayed on immatures of host insect had more effect as compared to leaf dip procedure. Furthermore, no significant effect of concentrations was observed on sex ratio.


2019 ◽  
Vol 20 ◽  
pp. 101262 ◽  
Author(s):  
Alagersamy Alagesan ◽  
Balakrishnan Padmanaban ◽  
Gunasekaran Tharani ◽  
Sundaram Jawahar ◽  
Subramanian Manivannan

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