A field trial was conducted at Rice Research Station, Hooghly of West Bengal during boro season to evaluate the effect of some biorational and microbial insecticides against rice insect-pests. Insecticides of different origins such as, Beauveria bassiana Balsamo-Crivelli, Bacillus thuringiensis Berliner, Metarhizium anisopliae Metchnikoff, spinosad, azadirechtin, and cartap hydrochloride as check, have been tested in different combinations against yellow stem borer (Scirpophaga incertulas Walker) and whorl maggot (Hydrellia spp. Robineau-Desvoidy). The lowest whorl maggot infestation was recorded in spinosad treated plots (1.84%) followed by B. thuringiensis var. kurstaki (2.58%) and azadirachtin treatment (2.59%). The lowest yellow stem borer infestation as dead heart was recorded in plots treated with spinosad (2.92%) followed by M. anisopliae (3.32%) followed by azadirachtin (3.44%). The white ear head damage was recorded lowest in spinosad (8.04%) followed by B. bassiana + B. thuringiensis var. kurstaki (9.25%) and M. anisopliae treatment (9.48%). The highest grain yield and straw yield of boro rice were obtained from the plots treated with spinosad (57.72 q ha-1 grain yield and 6958 kg ha-1 straw yield) followed by B. bassiana + B. thuringiensis var. kurstaki (54.31 q ha-1 grain yield and 6681 kg ha-1 straw yield) followed by B. bassiana + M. anisopliae (53.47 q ha-1 grain yield and 64.58 q ha-1 straw yield). The overall results revealed spinosad as the most effective insecticide against both the insect species whorl maggot and yellow stem borer, showing minimum white ear head and dead heart with higher grain and straw yield.

Keywords: Beauveria bassiana, Bacillus thuringiensis, Metarhizium anisopliae, Spinosad, Scirpophaga incertulas, Hydrellia spp

This study was conducted to check for the biological efficacy of root exudates of Clerodendron inerme on some biological aspects of Aphis craccivora. Also, the study included the detection of the compounds in root exudates of C. inerme by using the gas chromatography-mass spectrometry technique. Results showed that the high concentration of root exudates recorded high cumulative mortality of the adult insects after exposure time 1, 2, and 3 days from treatments 28.5, 33.8, and 40.3% respectively compared with 32.4, 39.3 and 48.5% respectively of nymphs insects. The developmental period of the immature stages has increased from 6.5days in the control treatment compared with 9.3 days at high concentration while the fecundity of adult females reduced to reach 18.00 nymph at high concentration compared with 26.66 nymphs in the control treatment. GC-MS analysis of root exudates of C. inerme showed the presence of many compounds such as2-Propenoic acid, ethenyl ester, 2-Phenanthrenol.

Keywords: Aphis craccivora, Clerodendron inerme, GC-MS Analysis

The saw-toothed grain beetle, Oryzaephilus surinamensis (L.) is considered one of the mostserious insect pests which attack different stored products in all over the world. This study wascarried out in the Laboratory of Plant Protection Department, Faculty of Agriculture, Zagazig University, Egypt to study the susceptibility of six dry date, Phoenix dactylifera (L.) varieties (Malkabi, Skooty, Pertomoda, Shamia, Dekina and Gondella) to infestation with the saw-toothed grain beetle under non-choice and free-choice conditions. Parameters of evaluation among the tested varieties as regards resistance were mean complete developmental period, number of F1 emerged adults, susceptibility index and weight loss % after one and three months of storage. Results showed that the shortest mean complete developmental period of the insect was 28.33 days on Skooty variety, while the longest one was 33.67 days on Gondella variety in free–choice bioassay method. Dekina variety was the most preferred variety to the insect since their fruits produced the highest mean insect number of progeny (73.67 adults), whereas Skooty variety recorded the lowest mean (25.67 adults). Values of susceptibility index (SI) ranged between 4.38% for Gondella and 10.69% for Skooty. After one month of storage the percentage of wet weight lossranged between 1.83 in Pertomoda and 10.83% in Malkabi, while after three months of storage the lowest rate was 5.83 % in Gondella variety and the highest one (25.67%) was detected in Malkabi variety. The relative wet weight loss percent reached the highest value (30.80%) in Malkabi variety and the lowest one was 5.20% in Pertomoda after one month of storage. After three months of storage, Malkabi date variety recorded the maximum value of the relative wet weight loss(28.84%), whereas the minimum value (6.55%) was recorded in Gondella variety. The results clear that all tested dry date varieties were infested with O. surinamensis and no immune variety wasfound free from the insect infestation with preferable some tested varieties to the insect.

The insect Myllocerus viridanus in mulberry cultivation (Morus alba) causes significant harm to sericulture industry throughout the year which hampers leaf quality, silkworm rearing, and cocoon production. In this study, the treatment with neem oil (Azadirachta indica) in five different concentrations (1 to 5ml/L) along with mild soap solution (Khadi) to assess the mortality of M. viridanus at laboratory conditions. The lethal concentrations (LC30 – 3.096;LC50 – 3.471; LC90 - 4.589) were determined by spraying of the neem oil solution to adults of M. viridanus. The results showed that neem oil effectively suppressed M. viridanus and that the mortality of M. viridanus increased gradually (34 %, 44 %, 60 %, 78 %, and 100%) over the control as the concentration of neem oil increased. 

Endophytic fungi are fungi that that live inside healthy plant tissues without causing diseases which can be used as biological control agents of shallot pests. The purpose of this study was to obtain types of endophytic fungi that are pathogenic to Tenebrio molitor and Spodoptera litura larvae (entomopathogens). Endophytic fungi were isolated from healthy plant (roots, bulbs, stems, and leaves) using Malt Extract Agar (MEA) medium. The pathogenicity test of the isolated endophytic fungus was carried out on the larvae of Tenebrio molitor and Spodoptera litura. The results showed that out of the 34 isolates tested; only eight isolates (23.52%) were entomopathogenic. Pathogenic nature is indicates the presence of mycosis symptoms in T. molitor larvae. The mortality of T. molitor larvae after the application of endophytic fungi ranged from 5.0 – 17.5%. These isolates are also pathogenic to S. litura larvae, but the mortality ranged from 8-56%. The endophytic fungus that is pathogenic to insect (entomopathogen) belong to Aspergillus, Fusarium, and Trichoderma.

Coffee berry borer (CBB), Hypothenemus hampei (Ferrari) is one of the most important pests of coffee marketed in Cameroon and the world. This insect lives an endophytic life in the berries and remains very difficult to fight with the spraying of synthetic pesticides. This study aims at investigating the potential impact of two native strains of Beauveria bassiana (Balsamo) Vuillemen (Deuteromycotina: Hyphomycetes) from Cameroon against the CBB. B. bassiana strains were isolated from rhizosphere strains of coffee farms. The efficiency tests were conducted on adult H. hampei. Five treatments of B.bassiana were used compared with Pyriforce (Chlorpyriphos-ethyl). Results indicate that, the B. bassiana strains were different in terms of their macromorphological characteristics. They were virulent against the CBB irrespective of the mode of application of spores directly to the borer as well as to the berries. These results clearly showed that the two isolates of B. bassiana, native to coffee growing areas in Cameroon, can be used as potential biological control agents against H. hampei and as alternatives to chemical insecticides in integrated pest management programmes for coffee.

The present study aims to isolate endophytic actinomycetes (EPM) that are able to tolerate abiotic stresses, solubilize tricalcium phosphate (TCP) and produce indole-3-acetic acid (IAA), amylase and cellulose activities, while exhibiting high antagonistic activity against Fusarium oxysporum. f. sp. albedinis. Endophytic actinomycetes were isolated from roots, stems and leaves of Thymus saturoides and Lavandula multifida plant grown in Beni Mellal region, Morocco. According to the macro- and micro-morphological characteristics, a total of eleven EPM isolates were isolated and purified. Results indicated that the majority of isolates were able to tolerate pH and salt stresses. Moreover, the majority of the isolates were able to solubilize TCP on Pikovskaya (PVK)-agar medium which ranged from 25% to 458%. Additionally, on PVK-liquid medium, soluble phosphate content varied from 163.81 µg/mL recorded for the isolate LRP1 to 730 µg/mL observed for the isolate TSRP2. For IAA production, the amount produced varied from 1.70 µg/mL recorded for the isolate LRP1 to 14.13 µg/mL recorded for both LTP2’ and TSRP2. Endophytic actinomycetes isolated in this work also showed a remarkable capacity to degrade some compounds such as cellulose and starch. In addition, some of them showed a strong inhibitory activity against the fungus F. albedinis with a percentage of inhibition ranged from 69.13% observed for LTP2’ to 86.6% recorded for the isolate LRP2. Results from this study indicate that the two isolates LTP2’ and TSRP2 were the most efficient and that actinomycetes could be used in biocontrol against the fungus F. albedinis.

ABSTRACT 

The entomopathogenic fungus, Nomuraea rileyi (Farlow) Samson was isolated from the cadavers of Diaphania caesalis (Walker) collected from the jackfruit field of ICAR_IIHR, Bengaluru. This detection represents the first report of N. rileyion D. caesalis. Pathogenicity of N. rileyi isolate against different larval instars of D. caesaliswas studied by topical application of spores at concentrations of 10 and 10°conidia per ml. Early larval instars were more susceptible, which decreased significantly as the larval age advanced. 

Key words: Natural enemies, Biological control, Bioassay, Pathogenicity