DETECTION OF THE RED PALM WEEVIL RHYNCHOPHORUS FERRUGINEUS USING ITS BIOACOUSTICS FEATURES

ABSTRACT

The Red Palm Weevil (RPW) is the most destructive pest of the date palm in the world and a serious pest of coconuts. The insect has caused up to 20% loss of these plantations in Asia and the Middle East. The economic damage to palm crops due to RPW could be mitigated significantly by bioacoustics recognition in an earlier phase of infestation and by applying the appropriate treatment. This study is conducted under the hypothesis that distinctive spectral and temporal features in RPW larval sounds can be combined to construct improved indicators for automated detection of infestations. In this paper, a signal processing system is developed with available acoustic technology to detect the existence of RPW in a tree through its feeding sounds. A large set of features are extracted, including unconventional features such as temporal roll-off, temporal slope and temporal spread. Additionally, an analysis is provided of the criteria for the choice of the optimum frame length, as well as the selection of the suitable window function. The results confirm the efficiency of the developed system with the selected representative features, window functions and frame length to detect the existence of the RPW.     

A microglandular adenosis-like lesion simulating tubular adenocarcinoma of the breast. A case report with cytological and histological appearances

Although rare, microglandular adenosis of the breast is well recognized as a benign lesion which mimics tubular adenocarcinoma. In this paper we present a case of a complex microglandular adenosis-like lesion which was thought to be suggestive of tubular adenocarcinoma by fine needle aspiration cytology. The problem of the cytological distinction of microglandular adenosis from tubular adenocarcinoma is discussed.     

Significance of Borderline Nuclear Abnormality In Cervical Smears

Women with cervical smears showing borderline nuclear abnormality (BNA), or reactive changes in the form of squamous metaplasia (SM) or endocervical cell hyperplasia (ECH), were age-matched with healthy controls to determine the outcome of these conditions. No significant difference in the risk of dyskaryosis was observed in cases showing reactive changes and the controls. In contrast, there was a 23% excess of cases showing dyskaryosis in the repeat smears of cases of BNA over the controls. An odds ratio of 8.3 was obtained, showing dyskaryosis in subsequent smears after a diagnosis of BNA.     

Fungal Assciations: I. Synergistic Relation between Rhizoctonia solani Kuhn and Fusarium solani Snyder and Hansen in causing a Potato Tuber Rot

Rhizoctonia solani, Fusarium solani, and Phoma foveata werechosen for the study of disease caused by these fungi in differentcombinations in potato tubers. An initial Rhizoctonia infection,when followed by a Fusarium infection, gave an extensive rottingwith external pimple-like formations in some cases. This typeof rotting could not be brought about by individual infectionswith either of the two fungi, or jointly by them when Fusariumwas inoculated first. Microscopic observations of infected matureand young potato tubers showed that Rhizoctonia grew intracellularlywhen infected alone, whereas it grew inter- as well as intra-cellularlyin the successive double infection. Fusarium formed more haustorium-likestructures when inoculated alone that when it followed Rhizoctonia.The length of these structures in the double infection was greaterin mature than in young tubers. Atmospheric humidity affectedthe amount of rotting, the shape and colour of the rot, andthe morphology of the fungus in the tissue.     

Fungal Assciations: II. Cultural Studies on Rhizoctonia solani Kuhn, Fusariutn solani Snyder and Hansen, and Other Fungi, and Their Interactions

Several types of interaction between Rhizoctonia solani, Fusariumsolani, and Phoma foveata were found when these fungi were grownon potato-dextrose agar. After being used by Rhizoctonia a potatomash medium gave better growth of Rizoctonia and Fusarium thanit did when the medium was initially used by Fusarium; and thiswas so whether the reaction of the spent medium was readjustedor not. It is suggested that potato mash medium used by Fusariumcontains a thermostable factor(s) affecting the subsequent growthof Rhizoctonia or Fusarium. The range of pH values suitable for Rhizoctonia growth was narrowerthan that for Fusarium, optimum values being approximately 5•9for the former and 7•8 for the latter. In mixed culturesof the two fungi on potato-dextrose agar adjusted to differentpH values, the fungus for which the reaction of the medium wasmore suitable usually became visually predominant after sometime. A study of various carbon sources showed that poor growth ofRhizoctonia was obtained when pectin was used as the sole sourceof carbon. On a pectin-agar medium, the rate of growth of aRhizoctonia colony increased on the sector which lay towardsan adjacent Fusarium colony; also, after the two fungi camein contact, there was more rapid growth of Rhizoctonia roundthe Fusarium colony than elsewhere. On a synthetic liquid mediumwith pectin as the carbon source better Rhizoctonia growth wasobtained when Fusarium-spent medium was added to it than whenRMzoctoma-spent medium was added. Rhizoctonia showed partial deficiencies in thiamine, biotin,and inositol. Both the extract of Fusarium mycelium, grown onvitamin-free medium, and the Fusarium-spent medium, stimulatedthe growth of Rhizoctonia on vitamin-free medium.     

On the role of sinigrin (mustard oil) in a tritrophic context: plant–aphid–aphidophagous hoverfly

1. Plant secondary metabolites can govern prey–predator interactions by altering the diet breadth of predators and sometimes provide an ecological refuge to prey. Brassicaceae plants and their specialist pests can be used as a model system for understanding the role of chemically mediated effects restricting the diet breadth of natural enemies, and consequently the occurrence of enemy‐free space for the specialist pest. 2. The objective of the present study was to test the performance of the generalist predator Episyrphus balteatus De Geer (Diptera: Syrphidae) fed on the specialist herbivore Brevicoryne brassicae L.(Homoptera: Aphididae), reared on two different brassica species: black mustard (Brassica nigra), a wild species with high levels of sinigrin; and canola (Brassica napus), a cultivated species without sinigrin. 3. The preference and performance of the predator and the performance of the prey were measured. Sinigrin was quantified by high‐performance liquid chromatography in both leaf samples and aphids reared on the two host plants. 4. The cabbage aphid performed better on canola than on black mustard. The performance of the predator on this aphid when reared on canola was clearly better than when reared on black mustard. Females had a higher overall preference for cabbage aphids reared on canola than on black mustard. 5. The ability of aphids reared on plants with high glucosinolate content to reduce the performance of their generalist predators indicates that the presence of B. nigra may provide enemy‐free space for the cabbage aphid from its predator, a concept that has useful application in the context of biological control for agricultural systems.     

The Cytological Prediction of Cervical Intraepithelial Neoplasia In Colposcopically Directed Biopsies

The tissue sections and preceding cervical smears of 1262 women who had colposcopic cervical biopsies were reviewed and the reports correlated. Close correlation between the cytological and histological findings, to within one histological grade of cervical intraepithelial neoplasia (CIN), was noted in 86% of cases. However, the biopsy was negative, or contained evidence of wart virus infection only, in 24% of cases where dyskaryotic cells had been observed in the cervical smear. Of particular concern was the fact that negative histological findings were recorded in 13% of cases where the smear contained cells showing a moderate dyskaryosis and in 1.26% of cases where the smear showed severe dyskaryosis. This suggests that colposcopically directed biopsies do not always reflect the underlying pathological changes in the cervix. Management of these cases is discussed. In 45 women with a normal cervical smear prior to biopsy, histology revealed seven cases of CIN 3 and one case of invasive squamous carcinoma. This indicates that referral for colposcopy is advisable whenever there is clinical suspicion of cancer, even if the cervical smear report is normal.     

Fungal Associations: III. The Role of Pectic Enzymes on the Synergistic Relation between Rhizoctonia solani Kuhn and Fusarium solani Snyder and Hansen, in the Rotting of Potato Tubers

The greatest activity of protopectinase obtained from the growthof Rhizoctonia solani and Fusarium solani on autoclaved potatoplugs occurred at pH 6.5, and greatest activity of the ‘lossof viscosity’ enzyme was found at 6–5 for Rhizoctonia,and between 6.5 and 8.3 for Fusarium. Protopectinase enzymeobtained from double infections of the Fusarium spp. with Rhizoctonia,or by mixing the enzymes of individual Fusarium spp. with Rhizoctoniaenzyme, were more active than the enzymes from single inoculations.Cylindrocarpon radicicola enzyme was more active when obtainedfrom a pure culture than from double infection. Similarly, mixingthis enzyme with the enzyme of Rhizoctonia reduced its activity.The evidence indicated that the protopectinase of Rhizoctoniawas similar to that of Cylindrocarpon and differed from thatof the Fusarium spp. Using paper partition chromatography, two bands from Rhizoctoniacrude enzyme had a stimulatory effect on Fusarium enzyme, whileonly one band from Fusarium enzyme stimulated Rhizoctonia enzyme. The purified enzyme of Rhizoctonia degraded pectin to galacturonicacid. Fusarium pure enzyme degraded pectin to an intermediatestage. A mixture of the two enzymes degraded pectin to galacturonicacid, without the intermediate stage formed by Fusarium alonebeing detected. The role played by pectic enzymes upon the synergistic relationof Rhizoctonia solani and Fusarium solani on rotting potatotubers is discussed.