The occurrence of entomopathogenic fungi isolated from stored grain insect pests sampled from various geographical regions of Punjab, Pakistan, was investigated. In total, 25,720 insects from six different species were evaluated, and 195 isolates from 24 different fungal species were recovered. These included the Ascomycetes Beauveria bassiana sensu lato (Balsamo) Vuillemin (Hypocreales: Clavicipitaceae) , Metarhizium anisopliae sensu lato (Metschnikoff) Sorokin (Hypocreales: Clavicipitaceae), Purpureocillium lilacinum (Thorn) Samson (Hypocreales: Ophiocordycipitaceae), and Lecanicillium attenuatum (Zare and W. Gams) (Hypocreales: Clavicipitaceae). The cadavers of red flour beetle Tribolium castaneum (Herbst.) (Coleoptera: Tenebrionidae) were significantly infected with the fungi followed by rice weevil Sitophilus oryzae (L.) (Coleoptera: Curculionidae), lesser grain borer Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae), rusty grain beetle Cryptolestes ferrugineus (Stephens) (Coleoptera: Cucujidae), and cowpea weevil Callosobruchus maculatus (F.) (Coleoptera: Bruchidae); however, the least were recovered from khapra beetle Trogoderma granarium (Everts) (Coleoptera: Dermestidae). The geographical attributes (altitude, longitude, and latitude) greatly influenced the occurrence of entomopathogenic fungi with highest number of isolates found from >400 (m) altitude, 33°–34′ N latitude, and 73°–74′ E longitude. The findings of the current surveys clearly indicated that the entomopathogenic fungi are widely distributed in the insect cadavers, which may later be used in successful Integrated Pest Management programs.

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The red palm weevil Rhynchophorus ferrugineus (Olivier) is an important pest of date palms in many regions of the world. This paper reports the first survey of insecticide resistance in field populations of R. ferrugineus in Pakistan which were collected from seven date palm growing areas across Punjab and Khyber Pakhtunkhwa (KPK) provinces, Pakistan. The resistance was assessed by the diet incorporation method against the formulated commonly used chemical insecticides profenophos, imidacloprid, chlorpyrifos, cypermethrin, deltamethrin, spinosad, lambda-cyhalothrin and a fumigant phosphine. Elevated levels of resistance were recorded for cypermethrin, deltamethrin and phosphine after a long history of insecticide use in Pakistan. Resistance Ratios (RRs) were 63- to 79-fold for phosphine, 16- to 74-fold for cypermethrin, 13- to 58-fold for deltamethrin, 2.6- to 44-fold for profenophos, 3- to 24-fold for chlorpyrifos, 2- to 12-fold for lambda-cyhalothrin and 1- to 10-fold for spinosad compared to a susceptible control line. Resistant R. ferrugineus populations were mainly found in southern Punjab and to some extent in KPK. The populations from Bahawalpur, Vehari, Layyah and Dera Ghazi Khan were most resistant to chemical insecticides, while all populations exhibited high levels of resistance to phosphine. Of the eight agents tested, lower LC50 and LC90 values were recorded for spinosad and lambda-cyhalothrin. These results suggest that spinosad and lambda-cyhalothrin exhibit unique modes of action and given their better environmental profile, these two insecticides could be used in insecticide rotation or assist in phasing out the use of older insecticides. A changed pattern of both insecticides can be used sensibly be recommended without evidence of dose rates and frequencies used.

Nineteen different isolates of the entomopathogenic fungi Beauveria bassiana sensu lato (s.l.) and Metarhizium anisopliae s.l. (Ascomycota: Hypocreales), recovered from different soil samples (field crops, fruit orchards, vegetable fields and forests) and insect cadavers were tested against Rhynchophorus ferrugineus (Olivier) (Coleoptera: Curculionidae) at two different spore concentrations (1 × 107 and 1 × 108 conidia mL−1). Three isolates of B. bassiana and two of M. anisopliae gave >88 % larval and >75 % adult mortality of R. ferrugineus on their highest dose rate respectively. More sporulating cadavers (mycosis) resulted from a high dose rate compared to low dose on both life stages of R. ferrugineus. The current study confirmed the lethal action of B. bassiana and M. anisopliae isolates with mortality levels usually directly proportional to the conidial concentration. This study further confirmed that the isolates recovered from R. ferrugineus dead cadavers gave more mortality compared to the other sources. In the virulence assay two isolates of B. bassiana caused the highest percentage of both larval and adult mortality at all exposure intervals which suggest that they may be the most promising for use in sustainable management programs aimed at microbial control in date palm orchards.