By B. Baldar. Wilberforce University. 2019.
The diastolic rumble is produced by the large flow volume crossing the mitral valve discount geriforte 100 mg free shipping quality herbals. Patent ductus arteriosus and aortopul- monary window have continuous flow from the aorta into the pulmonary artery cheap geriforte 100mg online herbals dario bottineau, resulting in a murmur that has late systolic accentuation discount geriforte 100mg online herbals on demand reviews, then crosses S2 into early diastole cheap geriforte 100 mg without a prescription quality herbals products pvt ltd. Often, multiple systolic clicks like the sound of water moving over a water-wheel can be heard, probably due to increased flow in the dilated pulmonary artery or ascending aorta. Heart Disease Presenting in Childhood or Adolescence Since most serious congenital defects present in infancy, heart disease presenting later is typically either asymptomatic or difficult to detect, progressive in severity leading to later presentation, or acquired. Occult Congenital Defects Atrial septal defects often go undetected for several years, as they rarely cause symptoms in infancy but may result in decreased exercise tolerance in the adoles- cent. The classic findings on cardiac examination are a fixed and widely split S2, best heard at the mid to upper sternal border. There may be a grades 1 2/6 systolic ejection murmur at the left upper sternal border of increased flow across the pulmonary valve ( relative pulmonary stenosis ) and a diastolic low-pitched rumble at the left lower sternal border of increased flow across the tricuspid valve. Obstructive lesions such as aortic stenosis or coarctation that present later, are nonductal dependent, progressive lesions that rarely cause symptoms until severe. The murmur of aortic stenosis is a harsh, throat-clearing systolic ejection murmur, best heard at the right upper sternal border. Coarctation of the aorta results in systolic hypertension in the upper extremities, decreased pulses and blood pressure in the lower extrem- ities, and a systolic ejection murmur best heard over the left back or left axilla. The patient should be placed in the left lateral decubitus position to detect this murmur. Cardiomyopathy Familial hypertrophic cardiomyopathy often presents in the 14 18-year-old age range, when it is also most likely to result in sudden death in the athlete, accounting for approximately 40 50% of sudden cardiac death in the teenaged athlete in the United States. Symptoms include shortness of breath, chest pain, dizziness, or syncope with exercise. Family history of heart disease or sudden death prior to age 40 should raise index of suspicion. In 25% of patients, there is dynamic left ventricular mid cavity obstruction that results in a systolic ejec- tion murmur that increases in intensity in the standing position. Cardiac auscultation may reveal an S3 4 summation gallop, best heard with the bell at the left lower sternal border or apex. Myocarditis Myocarditis should be suspected in any child with signs of heart failure who was previous well, especially with a preceding history of a viral illness. On cardiac exam there is often unexplained tachycardia and the heart sounds are usually muffled. The presence of ventricular arrhythmias indicates fulminant presentation and should prompt immediate transfer to the intensive care unit for potential cardiopulmonary support. Mehrotra Many newborn children appear to have cardiomegaly when in fact the thymus is contributing to the cardio-thymic shadow giving the appearance of an enlarged heart. Introduction Chest X-ray is an important tool in evaluating heart disease in children. Luxenberg diagnostic procedures is significant making their routine use difficult. History of present illness coupled with physical examination provides the treating physician with a reasonable list of differential diagnoses which can be further focused with the aid of chest X-ray and electrocardiography making it possible to select a management plan or make a decision to refer the child for further evalua- tion and treatment by a specialist. Approach to Chest X-Ray Interpretation Unlike echocardiography, chest X-ray does not provide details of intracardiac structures. Instead the heart appears as a silhouette of overlapping cardiovascular chambers and vessels. The size and shape of the heart as well as the pulmonary vascular markings, pleura and parenchymal lung markings provide helpful information regarding the heart/lung pathology. It is easy to be overwhelmed with a prominent pathology on a chest X-ray thus overlooking more subtle changes; therefore, it is imperative to conduct interpretation of chest X-ray carefully and systematically considering the fol- lowing issues. Heart size: The size of the heart represents all that lies within the pericardial sac. This includes the volume within each cardiac chamber, cardiac wall thickness, pericardial space, and any other additional structure such as mass from a tumor or air trapped within the pericardium (pneumopericardium). Therefore, enlargement of any of these structures will lead to the appearance of cardiomegaly on chest X-ray. Dilated atria or ventricles such as that seen in heart failure will cause the cardiac silhouette to appear large, as would hypertrophy of the ventricular walls or fluid accumulation within the pericardial space (Tables 2. Heart shape: The presence of certain subtleties in the cardiac shape may point to a particular pathology and thus help narrow the differential diagnosis. Enlargement or hypoplasia of a particular component of the heart will alter the normal shape of the cardiac silhouette. Therefore, each aspect of the heart border should be examined to assess for abnormalities. On the other hand, pulmonary atresia will cause the mediastinum to be narrow due to hypoplasia of the pulmonary artery. Pulmonary blood flow: Pulmonary vasculature is normally visible in the hilar region of each lung adjacent to the borders of the cardiac silhouette. An increase in pulmonary blood flow or congestion of the pulmonary veins will cause prominence of the pulmonary blood vessels. A significant increase in pulmonary blood flow 2 Cardiac Interpretation of Pediatric Chest X-Ray 19 Table 2. Pleural space: Heart failure results in venous congestion which may lead to fluid accumulation within the pleural spaces manifesting as a pleural effusion. Pleural effusion may be noted on chest X-ray as a rim of fluid in the outer lung boundaries of the chest cavity or as haziness of the entire lung field in a recumbent patient due to layering of the fluid behind the lungs. The right border of the cardiac silhouette consists of the following structures from top to bottom: superior vena cava, ascending aorta, right atrial appendage, and right atrium (Fig. The left border of the cardiac silhouette is formed from top to bottom by the aortic arch (aortic knob), pulmonary trunk, left atrial appendage, and the left ventricle. In the normal chest X-ray only the larger, more proximal pulmonary arteries can be visualized in the hilar regions of the lungs and the lung parenchyma should be clear with no evidence of pleural effusion (Fig. Lateral View The cardiac silhouette in this view is oval in shape and occupies the anterior half of the thoracic cage. A normal pulmonary blood flow pattern is present with no evidence of pleural disease 22 Ra-id Abdulla and D. The right ventricle is the anterior most part of the heart and occupies the middle region within the cardiac silhouette. The main pulmonary artery is to the left of the ascending aorta and forms a small portion of the middle of the left car- diac silhouette border as it courses posteriorly and bifurcates into right and left pulmonary arteries. The various cardiovascular components cannot be visualized by chest X-ray, however, knowledge of cardiac and vascular anatomy within the cardiac silhouette is helpful in understanding both normal and abnormal findings on chest X-ray (Fig. Change in the shape of the cardiac silhouette may point to specific cardiac structural abnormalities; for example, an uplifted cardiac apex points to right ventricular hypertrophy due to displacement of the left ventricular apex upward and laterally. We will now discuss some specific congenital cardiac lesions and their associated chest X-ray findings. An atrial septal defect causes an increase in heart size with fullness of the right heart border due to right atrial enlargement. The pulmonary arteries are full and may be well visualized even in the peripheral lung fields indicating an increase in pulmonary blood flow. In severe cases, the right ventricle is dilated and is noted as fullness of the anterior most aspect of the cardiac silhouette causing obliteration of the usual space between the heart and sternum. The increase in pulmonary blood flow will manifest as engorged pulmonary vasculature. The increase in return of blood to the left atrium and ventricle may cause left atrial and left ventricular dilation (Fig. An increase in pulmonary blood flow results in prominent pulmonary vasculature which may be noted in the peripheral lung fields.
University of California Press discount geriforte 100 mg without prescription herbs like viagra, Berkeley Kemsawasd J (1976) Leaf curl disease of chili caused by the broad mite Polyphagotarsonemus latus (Banks) and its control order geriforte 100 mg otc herbals uk. J Appl Entomol 129(6):315 322 Nugroho I generic geriforte 100 mg online himalaya herbals india, Ibrahim Y (2004) Laboratory bioassay of some entomophathogenic fungi against broad mite buy discount geriforte 100mg yashwant herbals. Nova Hedwigia 73:1 50 Enabling mycelial application of Hirsutella thompsonii for managing the coconut mite P. Sreerama Kumar Leena Singh Originally published in the journal Experimental and Applied Acarology, Volume 46, Nos 1 4, 169 182. In a series of laboratory experiments, glycerol, yeast extract powder and dehydrated malt extract broth were found to be the best among nine substances investigated as possible adjuvants for use on coconut palms in the eld along with H. In terms of the density of conidia generated on a mycelial mat the treatments varied highly signicantly in two methods, with glycerol showing an average of 106% increase over control. Better conidiation was observed under alternating light dark regime than under total darkness in all the treatments. Application of the fungus in combination with glycerol resulted in a tolerable mean nut damage grade of 2. Keywords Aceria guerreronis Adjuvants Coconut eriophyid mite Hirsutella thompsonii Mycelial application Introduction Aceria guerreronis Keifer (Acari: Eriophyidae), one of the most destructive pests of the coconut palm (Cocos nucifera L. Its occurrence in the Sultanate of Oman is also now conrmed (Sreerama Kumar, personal observation, 2007). India, which ranks third behind Indonesia and the Philippines in terms of coconut production, is the only one out of these three countries to be aficted with this nut-inhabiting mite. Both in India and Sri Lanka the other major coconut-producing country suffering from this pest since about the same time the acarofungal pathogen, Hirsutella thompsonii Fisher (mitosporic fungi: Hyphomycetes), is perceived as one of the most potent biological control agents for this pest (Sreerama Kumar and Singh 2000; Sreerama Kumar 2002; Fernando et al. Unlike most of the commercial mycopesticides, which contain only spores or conidia (Jenkins et al. Therefore, our simultaneous research focussed on reducing the production cycle (i. For a cryptic pest like the coconut mite, the amount of inoculum coming in direct contact with the pest immediately after application is negligible. The triggering of microepizootics within the niche of the perianth depends mostly on the sporulation of mycelia on the plant surface proximate to the infested nuts. The repeated cycles of sporulation on the plant surface determine the rate of spread of the disease in the mite population. Availability of enough nutrition should be ensured for the initial establishment and saprophytic growth of the fungus through inclusion of nutrients in the spray (McCoy and Couch 1982). Furthermore, since several environmental factors either directly or indirectly inuence the survival and persistence of fungal propagules (Roberts and Campbell 1977; Fuxa 1987), specically the delicate mycelial fragments, protection against these uctu- ating factors needs to be taken care of. Natural sunlight, in particular, is considered to be the harshest of factors as it is capable of killing fungi within hours of exposure (Moore et al. Moisture is another critical factor for the fungus to survive and propagate (Inglis et al. Several additives have multifar- ious qualities and are known to simultaneously act as a nutrient, humectant, sunscreen, etc. The investigations commenced with laboratory selection of suitable Diseases of Mites and Ticks 171 adjuvants and concluded with a eld trial that proved the ability of mycelia alone to bring down the population of A. Effect of different adjuvants on the growth characteristics of Hirsutella thompsonii Nine substances (Table 1) were tested for their suitability as adjuvants at 0. In all the experiments, incubations were done under a 12-h photo- period at room temperature (28 2 C). In experiment 2, the adjuvants were added separately to sterile deionised water and nine pellets were dunked in each test liquid (9 ml) separately for 30 min. Sterile insect-mounting pins (38 mm long) were used to pierce through the treated pellets at the rate of three beads per pin. Three such loaded pins were kept in 15-ml sterile glass vials at the rate of one pin per vial for each treatment and incubated for 48 h. At the end of the incubation period, pellets from each pin were transferred to 1 ml of sterile deionised water containing 0. In experiment 3, the ability of the fungal pellets to form a sporulating mycelial mat in the continuous presence of the adjuvants was assessed through two ways of pellet treat- ment. In the rst method, 5 ml of the biomass was transferred along with the spent medium to 15-ml glass vials and each adjuvant was added separately, swirled and incubated for 30 days by which time a sporulating mycelial mat (ca. In the second method, the adjuvant solutions were prepared separately, and the pellets obtained from 10 ml of shake-ask culture of H. In both methods, at the end of the incubation period, the 20-mm-diameter mycelial mat was transferred to 10 ml of 0. Growth and conidiation of mycelial pellets on excised parts of the coconut palm The following parts of the coconut palm (Purseglove 1972) were tested for their suitability as substrates for germination and conidiation of H. These plant parts were excised into 2 small pieces (2 9 2cm for at parts, or 5 cm long for cylindrical parts) or used as such (only tepals) with each piece serving as a replicate. Observations were recorded for growth and coni- diation of mycelial pellets frequently (at least three times in a 24-h period) for up to 96 h. Effect of simulated sunlight on the conidiation of Hirsutella thompsonii Mycelial beads of H. Pellets treated with Diseases of Mites and Ticks 173 only sterile deionised water served as control. A 1100-W air-cooled xenon arc lamp gave an 2 output spectrum closely resembling sunlight in a total exposure area of 560 cm inside the simulator chamber. After sunlight treatment, the lids were replaced and two sub-sets of three Petri dishes each for the adjuvants and control were further incubated at alternating light dark regime (12:12 h) and total darkness, respectively, for 48 h at room temperature. For non-irradiated control, a similar protocol was followed with Petri dishes enclosed in black paper while inside the simulator, but other incubation conditions remained the same. At the end of the incubation period, all pellets from each Petri dish were transferred to 5 ml of sterile deionised water containing 0. Pathogenicity of adjuvant-treated pellets Before the eld trial, the three best adjuvants were tested for their effect on the patho- genicity of H. Chips (20 mm diameter) were sliced from beneath the perianth of young, freshly harvested 2 nutlets showing very high mite infestation ([20 live adult mites/mm ) after carefully removing the bracts. The pellets treated as in the plant parts study were rst allowed to germinate for 24 h and then transferred to the surface of the chip contained in the centre of a clean 200-mm glass Petri dish, at a rate of ve pellets per chip. The Petri dishes arranged in this manner were then closed and kept at room temperature with a 12-h photoperiod. The formulation process and ingredients, including the carrier and the additives (or formulants) incorporated into the nal product were the same as the original product. A block of 84 palms (7 rows 9 12 palms) at the centre of the grove was selected, out of which the rst three rows were used as a set for the fungal treatment and the last two as a set for the chemical and control treatments, with a buffer of two untreated rows in between these sub-blocks. The individual treatments were randomised 12 times each within their respective sets. After harvesting the mature coconuts from each experimental palm, the bunches were numbered by considering the fully open inorescence as the rst bunch and the preceding older bunches sequentially as second, third, etc. The second and third bunches were tagged by tying insulated electric wire of the best-visible colours, viz. For obtaining pre-treatment population data, the third nutlet from the bottom of the bunch was sampled from the fourth and fth bunches. Following the pre- treatment sampling, all the bunches were treated with the specic spray uid (2 l/palm) using a portable, lightweight, hand-compression sprayer (3. All the spray uids were prepared in plain water and applied thrice as sprays at fortnightly intervals during early mornings. The post-treatment population count of the mite was recorded in all the palms 6 weeks after the rst round of treatment. Population counts were made on two nuts, one each from both the tagged bunches, in the same way as pre-treatment analysis. Finally, during the pre- harvest stage, both the tagged bunches were cut off entirely from the palm and brought down for grading.
This chapter has attempted to distill the current concepts generic geriforte 100mg herbs pool, to offer a diag- nostic and therapeutic approach purchase 100 mg geriforte with visa herbals are us, and to expand the therapeutic options discount geriforte 100 mg without a prescription herbals 2. Distinguishing androgenetic alopecia from chronic telogen efuvium when associated in the same patient; a simple noninvasive method geriforte 100 mg lotus herbals. Distinguishing Androgenetic alopecia from chronic telogen efuvium when association in the same patient: a simple noninvasive method. Telogen efuvium as a clinical presentation of human immunodeciency virus infection. Acne in adult women: data from a national study on the relationship between type of acne and markers of clinical hyperandrogenism. Prolactin and its receptor are expressed in murine hair follicle epithelium, show hair cycle-dependent expression, and induce catagen. Estrogen receptor alpha, but not estrogen receptor beta, is involved in the regulation of the hair follicle cycling as well as the thickness of the epidermis in male mice. Inuence of estrogens on the androgen metabolism in different subunits of human hair follicles. Serum ferritin as a measure o6f iron stores during and after normal pregnancy with and without iron supplements. There is no clear association between low serum ferritin and chronic diffuse telogen hair loss. Non-anaemic iron deciency as an etiology factor in diffuse loss of hair of the scalp in women. Zinc induced copper deciency: a report of three cases initially recognized on bone marrow examination. Finasteride treatment may not prevent telogen efuvium after minoxidil withdrawal. The effects of minoxidil, 1 zinc pyrithrione an a combination on both on hair density: a randomized controlled trial. Reversal of Androgenetic alopecia by topical ketoconazole: relevance of anti-androgenic activity. Contact dermatitis to propylene glycol and dodecyl gallate mimicking seborrheic dermatitis. Dandruff- associated smouldering alopecia: a chronobiological assessment over 5 years. Oral terbinane in the treatment of multi-site seborrheic dermatitis: a multicenter, double-blind placebo-controlled study. Fluconazole and its place in the treatment of seborrheic dermatitis new therapeutic possibilities. Stress inhibits hair growth in mice by induction of premature catagen development and deleterious perifollicular inammatory events via neuropeptides substance P- dependent pathways. Burden of hair loss: stress and the underestimated psychosocial impact of telogen efuvium and Androgenetic alopecia J Invest Dermatol 2004; 123(3):455 457. The importance of dual 5 alpha reductase inhibition in the treatment of male pattern hair loss: Results of a randomized placebo-controlled study of dutasteride versus nasteride. Effects of minoxidil 2% vs cyproterone acetate treatment on female Androgenetic alopecia: a controlled, 12 month randomized trial. Topical liposome targeting of dyes, melanins, genes, proteins selectively to hair follicles (Review). In vitro permeation and in vivo depositon studies using hamster ank and ear models. Our challenge is to harness the knowledge we have gained in hair biology to improve our understanding of these incredibly devastating diseases that leave patients with permanent hair loss. Fortunately, prog- ress is occurring, including efforts to clarify clinical and histologic classication of the diseases, and to identify major areas of interest in research. This classication was based on the predominant histologic inammatory inltrate (Table 1) (1). It was hoped that the classi- cation would serve to clarify and unify the often vague or divergent terminology and diagnostic categories found in the literature and to facilitate collaborative trials to determine pathogenic fac- tors and effective therapeutic options (1). The sebotrophic mechanism puts forth the notion that the desquamation of the inner root sheath is dependent on the normal function of the sebum and that the absence of the normal gland leads to obstructed outow of the hair shaft. Furthermore, biopsies of clinically unaffected scalp in patients with lichen planopilaris have shown early sebaceous gland atrophy (2). This is where the slow-cycling hair follicle stem cells that are capa- ble of initiating follicular renewal at the end of the resting phase of the hair cycle are located. Studies suggest that the hair follicle stem cells and not the epidermal stem cells are injured in these disorders, however, whether these cells are a primary target or destroyed as an innocent bystander is a question that remains to be resolved (3). In normal anagen hair, macrophages are virtually absent from the hair follicle epithelium. It has been proposed that deletion of hair follicles may be caused by a macrophage-driven attack on epithelial hair follicle stem cells in the bulge of the outer root sheath under pathologic circumstances (15). Alternatively, the underlying pathophysiol- ogy may be similar to that seen with the lymphocytic scarring alopecias, however, bacteria may provide an ongoing nidus for inammation thus perpetuating the destruction of hair follicles. Signs of scalp inammation including erythema, scaling, pustules, scalp bogginess; compound follicles and wiry hairs are also commonly seen. Women are more commonly affected than men with an age of onset typically between 20 and 40 years; it is uncommon in children (25,26). Typical scalp lesions are round or discoid in appearance; follicular plugging and adherent scale may be present (Fig. The carpet tack sign may be elicited with retraction of the scale, revealing keratotic spikes that correspond to follicular openings on the undersurface (29). Presence of the disease in areas other than the scalp can make the diagnosis more certain. Patients are often quite symptomatic with itching, burning, and pain of the scalp. Examination reveals patchy alopecia or a more diffuse thinning of the scalp with characteristic perifollicular erythema and perifollicular scale at the margins of the areas of alopecia (Fig. Disease can be indolent or slowly progressive, but rarely involves the entire scalp. The pathogenesis of the disease seems to be unrelated to hormone replacement status. This disease presents as a bandlike fronto-temporal alopecia that progresses to involve the temporal-pari- etal scalp (Fig. Pseudopelade as described by Brocq presents with irregularly dened, white-colored, coalesc- ing patches of alopecia with atrophy and loss of follicular markings (Fig. Follicular hyperkeratosis and inammation is usually not seen and patients are usually without symptoms. The clinical presentation is frequently similar to alope- cia areata (thus the term pseudo pelade, the French word for alopecia areata) however on close inspection the characteristic loss of follicular markings distinguishes the two types of hair loss. The literature on hot-comb alopecia describes hair loss primarily in middle-aged black women, and suggests that specic haircare practices are associated with this disorder (37,39). As the name suggests, this disorder typically starts at the crown and advances to the parietal scalp; the reason for the hair loss in this typical pattern remains unexplained (1). Patients may complain of itching or discomfort, or have no symptoms at all, but notice an enlarging area of alopecia over time (Fig. Some classify this disorder along with a heterogeneous group of related disorders (keratosis pilaris atrophicans faciei/ulerythema opryogenes, atrophoderma vermiculata, and folliculitis spinulosa decalvans) under the umbrella of keratosis pilaris atrophicans (43). Tufted folliculits is sometimes considered a localized vari- ant of follicultitis.
The eVects of the pesticides were tested by direct application on only newly formed cadavers (not stored ones) and on conidia discharged from them buy generic geriforte 100mg herbals laws. Cadavers order geriforte 100mg otc herbals on deck, leaf discs or coverslips used in the bioassays were either dipped into trusted 100mg geriforte everyuth herbals skin care products, or sprayed with geriforte 100 mg amex herbals and their uses, the pesticides. The direct eVects were measured by immersing cadavers into the pesticides (cadaver treatment). The indirect eVect was measured by immersing leaf discs into pesti- cides (leaf treatment) before transferring the cadavers onto these discs. Similarly, direct and indirect eVects were tested by spraying cadavers on leaf discs or spraying leaf discs before transferring the cadavers onto them. Cadaver treatment Ten cadavers were introduced into microcentrifuge tubes and then 0. The content of each tube was then poured onto Wlter papers to drain the excess pesticides. Control cadavers were given the same treatments as described above except that they were introduced into distilled water amended with 0. After 2 h, the treated cadavers were individually placed on untreated discs of tomato leaves (1. The number of conidia discharged per mummy was estimated by observing the leaf disc directly under a compound microscope and scoring conidia numbers according to a categorical scale (0: no sporulation, 1: 1 100, 2: 101 500, and 3: >501 conidia). Sprayed cadavers were air-dried for 2 h and were then transferred individually onto unsprayed tomato leaf discs and processed as described above. A cadaver taken from the stock culture was then placed in the center of each disc, transferred onto moist sponge in a closed Petri dish and incubated at 25 C in darkness for 16 h, before sporulation was evaluated as described above. The coverslips with cadavers were then transferred onto a sponge soaked in distilled water in a closed Petri dish at 25 C in darkness for 16 h. Diseases of Mites and Ticks 291 Germination of conidia was observed using a compound microscope and the number of germinated and un-germinated conidia in Wve arbitrarily selected squares within the Weld of view was recorded using an enumeration counter. Total conidial germination included conidia that were in the process of forming or had already formed secondary conidia or capil- liconidia. Percent germination was computed by dividing the number of germinated conidia with the total number of conidia counted in a speciWed Weld and multiplying by 100. Only leaf discs with the highest spore numbers (category 3) were selected for the test. After 48 h of feeding on the treated leaf discs, the mites were transferred to new leaf discs each with a sporulating N. These mites stayed for 24 h on these leaf discs for contamination and were then transferred to new and larger leaf discs and observed daily for infection and mortality for 7 days. Dead mites were mounted and observed under the microscope for hyphal bodies to conWrm that the cause of death was N. Percentages germination and mortality were arcsine transformed before analysis to homogenize variances. A pre-planned compari- son between treatments was performed separately for each group of pesticide to determine within group treatment eVects. Xoridana sporulation was higher when the cadavers were immersed into pesticides than when sprayed (F35,324 =11. When cadavers were sprayed with the pesticides, Methomyl, Lambda-Cyhalothrin, Propargite and Abamectin had no eVect on sporulation at neither of the concentrations. Leaf treatment Cadavers placed on leaf discs that were immersed into Lambda-Cyhalothrin sporulated and produced as many conidia as the control (Table 3). In general, sporulation was signiWcantly higher when leaf discs were sprayed than when immersed in both Mancozeb and Captan (F11,108 = 11. Propargite and Mancozeb totally inhibited germination of conidia after immersion of coverslips. When coverslips were sprayed, germination was totally inhibited by Mancozeb and only 7. Lambda-Cyhalothrin and Captan also reduced germination in both application methods. Methomyl was the only pesticide that did not aVect germination when coverslips were either immersed or sprayed. Overall, germination of primary conidia was signiWcantly higher on coverslips that were sprayed than immersed (F29,60 = 22. More than half of the mites transferred to leaf discs treated with Propargite, Abamectin, Mancozeb or Lambda-Cyhalothrin died after 1 day indicating a direct eVect of the products on the mites and therefore these products were not used in the infectivity test (Table 5). Methomyl and Captan were the only pesticides used to test infectivity when leaf discs were either immersed or sprayed. Lower mortality of fungus- inoculated mites was observed when leaf discs were immersed rather than sprayed with Methomyl and Captan (F9,39 = 10. Neither Methomyl nor Captan aVected infectivity when leaf discs were sprayed with the pesticides. When cadavers were either immersed or sprayed, all pesticides except Mancozeb (not tested due to insuYcient sporulation) were used to test pathogenicity of the sporulating fungus. However, when cadavers were sprayed, mite mortality was higher than when immersed 294 J. Mean mortality of mites that were placed onto leaf discs contaminated with Methomyl, Captan or water (=control) before transfer to leaf discs with sporulating cadavers of N. Discussion The detrimental eVects of pesticides used to control insects, mites and fungal diseases in commercial tomato production on sporulation, germination and infectivity of N. Xoridana varied as a function of the methods of contamination, chemical nature and concentration. The fungicides Mancozeb and Captan that resulted in the most negative eVects on sporula- tion and germination of N. Xoridana in Tetranychus urticae Koch Diseases of Mites and Ticks 295 in peanut Welds. Acaricides such as Propargite, which do not inhibit sporulation but aVect primary conidia germination, may have a moderate eVect on the fungus in the Weld compared to those pesticides that inhibit sporulation because the life span of a primary conidium is much shorter than the life span of a mummiWed mite. However, any pesticide that inhibits the formation of capilliconidia, the only infective spores of N. No eVects on infectivity of the capilliconidia was observed from the pesticides after exposure. Seemingly, some pesticides inhibit sporulation or germination of primary conidia, but the capilliconidia produced under the exposure of these pesticides mantain the potential to infect their hosts. Viability of conidia is very important because the power of the fungus to kill its hosts depends on this factor as only viable conidia have the capacity to germinate and adhere to healthy hosts. It was expected that once the mites feed on pesticide contaminated leaves, they could ingest and accumulate the pesticides that may inhibit vegetative growth of the fungus and reduce mite mortality due to infection. Since the control mites were not subjected to pesticide contaminated leaf discs, higher mortality due to the fungus was anticipated. However, mor- tality in treatments with the insecticide Methomyl and the fungicide Captan was similar to the mortality in the controls suggesting that the pesticides did not aVect fungal development. Xoridana was higher when immersed than sprayed and this is probably associated with the amount of the product that the fungus is exposed to, despite being of equal concentration. DiVerences between the controls observed in the germination study were attributed to independent incubation of control lots together with each pesticide group. It is also possible that Tween 80, the surfactant used in the two controls, could have been the cause of diVerential germination because more of the products could be retained on the coverslips when they were immersed than sprayed. Although the spray tower method may give comparable results to Weld application of pesticides, the equipment may not be readily available in many laboratories, as a result, its use in pesticide testing may be limited. However, the eVect of direct immersion of leaf discs or cadavers into pesticide solutions is stronger and may not reXect a Weld situation, but it represents a rapid method to assess both direct and indirect eVects of these pesticides on the fungus and may assist in making quick decisions on the pesticides to be applied during pest attack. Also, if a product is considered compatible with the pathogen in this laboratory method (worst scenario) it may warrant selectivity in the Weld. The same line of thought applies to diVerences observed between maximum concentration and half the concentrations recommended for Weld application.
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