Showing papers in "Journal of Biological Control in 2002"

Efficacy of Trichoderma harzianum Rifai alone or in Combination with Fungicides against Sclerotium Wilt of Groundnut

Abstract: Trichoderma harzianum Rifai application either to soil as wheat bran saw dust (WBSD) preparation or on the groundnut seeds as spore coat proved effective against selerotium wilt caused by Sclerotium rolfsii Sacc. Synergistic and positive effects on disease control were registered when T. harzianum -WBSD preparation was applied to soil in integration with Vitavax or Vitavax-200. Integration of Thiram (seed coating) and soil application of antagonist was found compatible and synergistic. However, seed treatment with both antagonist and Thiram was found incompatible and hence may not be practically feasible for disease reduction.

Studies on the Artificial Diet for Beet Armyworm, Spodoptera exigua

Abstract: Based on our previously reported artificial diet for Spodoptera exigua (Hubner), a modified artificial diet, which could support the development of beet armyworm more satisfactory, had been developed by adding five micro compositions and reducing 50% casein of the diet. The results showed that beet armyworm reared on the modified diet not only had high survival rate, eggs laid per female and short larval development period as the previously reported diet, but also had higher hatching rate after reared consecutively for 12 generations. Now the modified diet had been used in the mass rearing beet armyworm for multiplying Spodoptera exigua nuclear polyhedrosis virus.

Bioefficacy and Shelf Life of Conidial and Chlamydospore Formulations of Trichoderma harzianum Rifai

Abstract: The conidia and chlamydospores of Trichoderma harzianum produced by solid state and liquid fermentation, respectively, were formulated as powder and tested for their comparative bioefficacy and shelf life. Both the propagules did not differ significantly in reducing root rot incidence in chickpea caused by Rhizoctonia solani . Conidial formulation retained optimum amount of viable propagules (>10 6 cfu/g) even after 180 days of storage at room temperature but in chlamydospore formulation, viable propagules reduced to less than 10 6 by 150 days.

Effect of transgenic Bt cotton on population of cotton pests and their natural enemies in Xinjiang.

Abstract: Systematic studies were carried out on the effect of Bt transgenic cotton on the population of the main pests and their natural enemies in Xinjiang in 2000-2001. The results showed that transgenic Bt cotton was highly effective in controlling cotton bollworm, Helicoverpa armigera. It also indicated that the populations of cotton aphid, Aphis gossypii and Lygus lucorum in the transgenic Bt cotton natural control field and the transgenic Bt cotton chemical control field were significantly higher than that in the common cotton field. As for natural enemies, the population of Chrysopa formosa increased in transgenic cotton fields. But predatory enemies such as Orius minutus, Deraeocoris punctulatus and several parasitic enemies decreased in transgenic cotton field of natural control and chemical control fields. The trend that the increasing population of piercing sucking pests such as Aphis gossypii and Thrips tabaci and decreasing of many natural enemies must be taken seriously. In consideration of the low population of cotton bollworm in Xinjiang, and no special control measure is necessarily required at present. It is suggested that the extension of high yield superior quality common cotton variety and the protection of natural enemies would achieve the aim of controlling pests and having a good yield.

Isolation of Endophytic Bacteria for Biological Control of Wilt Pathogens

Abstract: Twentyfive endophytic bacteria were isolated from internal tissues of root and stem portions of chickpea, sunflower, niger, chilli and capsicum plants. The endophytes were screened in dual culture on Potato Dextrose Agar (PDA) and Tryptic Soya Agar (TSA) against Fusarium oxysporum f. sp. ciceri, Fusarium udum, Rhizoctonia solani and Sclerotium rolfsii . Ten isolates exhibited inhibition of the pathogens. Maximum percent inhibition (37.93) of F. oxysporum f. sp. ciceri was obtained on PDA with B. subtilis (PDBCEN 3). On TSA percent inhibition was maximum (52.21) with isolate PDBCEN-7. Testing against F. udum in dual culture test revealed that Pseudomonas sp. (PDBCEN 8) showed maximum (40.45%) inhibition on PDA. Pseudomonas sp. (PDBCEN-2) was highly effective on TSA and showed maximum (56.9%) inhibition zone. Against R. solani , maximum inhibition (44.96%) was recorded with endophyte PDBCEN 7. On TSA all the ten endophytic bacteria were effective in restricting the growth of test fungus. Percent inhibition of S. rolfsii was maximum (40.93%) with Pseudomonas sp. (PDBCEN 6) on PDA. On TSA percent inhibition was maximum (46.73%) with P. fluorescens (PDBCEN 1). The endophytic isolates were able to promote better growth of chickpea but the vigour index varied between the isolates. We could not correlate high pathogen inhibition under in vitr o with high vigour index.

Evaluation of Antagonists against Jasmine Wilt Caused by Sclerotium rolfsii Sacc.

Abstract: The effectiveness of four species of Trichoderma namely T. viride Pres. ex. S. F. Gray, T. longibrachiatum Rifai, T. reesei Simmons, and T. harzianum Rifai, Gliocladium virens J. H. Miller, Giddens and Foster, two bacterial antagonists namely Pseudomonas fluorescens Migula and Bacillus subtilis (Chun) Praznowski and Saccharomyces cerevisiae Hansen was tested against Sclerotium rolfsii Saec. causing jasmine ( Jasminum sambac L.) wilt. P. fluorescens , B. subtilis and T. viride were found effective against sclerotial wilt. The volatile metabolites produced by these antagonists were also effective against S. rolfsii in vitro . The sclerotial germination of S. rolfsii was effectively inhibited by P. fluorescens , B. subtilis and T. viride . All the antagonists tested, except S. cerevisiae were effective in inhibiting the production of oxalic acid. Soil application of talc based commercial formulation of P. fluorescens @ 20 g/pot, B. subtilis and T. viride @ 25g/pot effectively reduced the wilt disease incidence in the pot culture experiment.

Ceratovacuna lanigera Zehntner (Homoptera:Aphididae) a Serious Pest of Sugarcane in Maharashtra and Attempts at its Management by Biological Means

Abstract: Serious and unprecedented infestations by the sugarcane woolly aphid, Ceratovacuna lanigera Zehntner were witnessed on the leaves of 4·9 month old sugarcane crop in Kolhapur and Pune districts of Maharashtra during September-October, 2002. During surveys for natural enemies, seven predators were recorded in Kolhapur, of which Dipha?aphidivora (Meyrick) was observed to be the most promising. In Pune district, only Cheilomenes sexmaculata (Fabricius) was recorded. Limited field releases of the coccinellid, Synonycha grandis (Thunberg) collected from the bamboo woolly aphids at Bangalore and the chrysopid, Chrysoperla carnea (Stephens) were made in a small area at Kolhapur. S. grandis adults and C. carnea eggs were recovered 2 to 3 weeks after release, indicating their survival in the field.

Integrated Application of Trichoderma Viride Pers.: Fr. and Farm Yard Manure to Control Damping-Off of Tomato [ Lycopersicum esculentum Mill.]

Abstract: In the present study, efforts were made to control the damping-off of tomato caused by Pythium indicum by using Trichoderma viride alone or in combination with farm yard manure (FYM). T. viride effectively controlled the disease in both sterilized and unsterilized soil than FYM when treated alone. But the combined treatment of T. viride and FYM showed better results in controlling the disease with concomineni increase In seedling length and biomass of tomato.

Biocontrol Based Management of Cotton Bollworms in the Punjab

Abstract: Two biocontrol based IPM modules, along with Punjab Agricultural University (PAU) spray schedules were evaluated for the management of cotton bollworms. IPM module II (3 sprays each for sucking pests and cotton bollworm + 8 releases of Trichogramma chilonis @ 1,50,000/ha/week + one release of Chrysoperla carnea @ 10,000/ha) was on par with PAU spray schedule in reducing the bollworm damage and increasing the yield. When T. chilonis (Bathinda strain) was integrated with insecticides it reduced the damage of bollworm by 70.3 percent and gave higher yield by 44.5 percent over insecticides alone.

Effect of Drying and Formulation of Conidia on Virulence of the Entomofungal Pathogen Nomuraea rileyi (F) Samson

Abstract: Drying Nomuraea rileyi conidia along with the solid substrate in an air stream gave a virulent product that gave high mortality of Spodoptera litura larvae in a laboratory bioassay whereas drying over silica gel or calcium chloride resulted in loss of efficacy. Bioassays with oil formulations of spores dried in an air stream resulted in comparable mortality of third instar S. litura (Fabr.) larvae with that of unformulated conidia. The oil formulation with Triton-X-100 caused significant reduction of S. litura populations feeding on groundnut and castor in field experiments. Natural parasitisation levels of two larval parasitoids on S. litura were similar in the fungus treatments and untreated controls.

Evaluation of Different Rearing Media for Corcyra cephalonica (Stainton)

Abstract: To determine the suitable food media for the mass production of Corcyra cephalonica (Stainton), eleven types of food media viz ., sorghum, pearlmillet, maize, coarse rice, wheat bran, rice husk, sorghum + rice husk (9:1), pearl millet + rice husk (9:1), pearl millet + rice husk + wheat bran (5:1:1), maize + rice husk (9:1) and rice + rice husk (9:1) were used for rearing. Observations were taken on average development period, percentage of moth emergence and weight of eggs. Food efficiency index (FEI) was calculated by dividing the product of percent emergence and egg weight by average development period. The FEI was highest in case of sorghum followed by pearlmillet, maize, pearlmillet + rice husk + wheat bran, sorghum + rice husk, wheat bran and rice, while in other food media it was extremely low.

Selection of Endophytic Antifungal Bacteria from Capsicum

Abstract: The endophytic antifungal bacteria were isolated and screened from Capsicum frutescens. Results indicated that population of endophytic bacteria ranged from 2.83×10 3 to 13 46×10 3 cfu per gram of fresh weight although it might vary depending on variety, tissue and planting location of the plant. Population of the endophytic bacteria were biggest in leaf, secondly in root, thirdly in stem and smallest in fruit. Leaf taken from capsicum planted in irrigated field harbored a bigger population of endophytic bacteria than that from non irrigated field. But for the endophytic bacteria in root, stem and fruit, plants growing non irrigated field harbored more than that frowing in irrigated field. Of the 108 strains isolated, 28 7% expressed antagonism against growth of Fusarium oxysporum f. sp. cubense and Fusarium oxysporum f. sp. cucumerinum. Two of them (BS 2 and BS 1) were found not only to be inhibitive to the growth of some fungal pathogens, but also have 57 34%-94 08% control effect to the anthracnose caused by Colletotrichum gloeosporioides. These two strains were identified as Bacillus subtilis.

Egg Parasitism of Rice Stem Borers in Regions with Different Rice Stem Borer Occurring Patterns

Abstract: Egg parasitism of rice stem borers in Changshu, Jiangyin, Jintan, Gaochun of Jiangsu province, and Hexian, Anhui province with different stem borer occurring patterns were investigated. The results showed that Trichogramma japonicum Ashmead was the dominant species in all these regions. There was significant difference in parasitism of striped stem borer in different regions. 100% egg masses in Changshu was parasitized by Trichogramma in the 1st generation of Chilo supperssalis and 82.3 wasps emerged from each egg mass. And in western Jintan only 17.1% eggs was parasitized and 3.5 wasps emerged per egg mass. Since the egg masses differed in size in different regions, so the control efficacy in Jintan was considered as the most prominent. In 1st generation Tryporyza incertulas eggs in Changshu and eastern Jintan were 100% parasitized and more wasps (31.3-28.7 wasps) emerged per egg mass than those in the other regions. Egg parasitism of rice borers of different generations varied greatly, e.g. in Jintan 38.3 wasps emerged per egg mass in the 1st generation, but no egg was parasitized in the 2nd generation, because frequent use of pesticides in the rice fields was fatal to Trichogramma wasps. In Hexian egg parasitism was higher in the 2nd generation than that of the 1st generation. The sex ratio of the Trichogramma wasps also varied with borer species and generations.

Historical Perspective of the Red Tree Ant, Oecophylla smaragdina and Its Utilization Against Citrus Insect Pests

Abstract: The red tree ant, Oecophylla smaragdina is an important natural enemy of citrus pests 1700 years ago the Chinese farmers had already used this ant successfully in biological control The present article review briefly the early history of using O smaragdina in pest control and discuss recent works on the biology of this ant and technics of application and conservation

Preliminary Studies on Effects of Transgenic Cotton Varieties on Composition of Insect Community

Abstract: Studies were carried out on the effect of transgenic cotton on insect pests and their natural enemies in Dafeng and Rugao cotton areas, Jiangsu. The results showed that no marked difference was found between 4 transgenic cotton varieties and traditional variety check in pests species and natural enemies. In Dafeng experiment the population of cotton bullworm on transgenic cotton was significantly lower than that of the check, indicating that transgenic cotton was highly resistant to cotton bullworms. But in Rugao region cotton aphid was the main pest. The population of cotton aphid on transgenic cotton was very high and chemical control was necessary. As both bullworm and aphid are important pests in many cotton growing regions further research works should be done to improve the control measures against these pests.

Role of Natural Enemies in the Management of Lipaphis erysimi (Kalt.) on Brassica juncea Var. Rugosa (Linn.)

Abstract: The role of natural enemies on the population of Lipaphis erysimi (Kalt.) infesting B. juncea var. rugosa (Linn.) has been studied in three consecutive crop seasons (1993-96). The study revealed the occurrence of about a dozen natural enemies belonging to four groups viz ., syrphids, coccinellids, hemerobiid and aphidiid. Among these, syrphids were found to be dominant over the others in terms of density, species composition and prey consumption potential.

Population dynamics of Helicoverpa assulta and Myzus persicae and their natural enemies in tobacco fields of Shandong Province.

Abstract: In tobacco fields of Shandong Province, population of the green peach aphid, Myzus persicae (Sulzer) reached its peak in late May to early June, and population of the oriental tobacco budworm, Helicoverpa assulta (Guenee), occurred from middle to late June. Predacious natural enemies included ladybirds, lacewings, predacious bugs, rove beetle and spiders, but populations were low and lagged behind the population peaks of insect pests. Aphidius gifuensis Ashmead, Campoletis chlorideae Uchida and Ovomermis sinensis Chen were the dominant parasitoids. Population of A. gifuensis correlated significantly with that of the green peach aphid and the ratio of A. gifuensis to aphid during the early season reached or approached 1. Parasitism of C. chlorideae against 1-3 instar larvae of the oriental tobacco budworm in June and July was 74 0% and 49.8% respectively. O. sinensis only occurred in middle July, and parasitism against larvae of the oriental tobacco budworm older than 3rd instar reached 35 2%.

Differentiation of Pseudomonas Strains through PAGE Banding Pattern

Abstract: Eleven Pseudomonas isolates of ten-plant species collected from all over Tamil Nadu were compared for their total cell proteins separated through sodium dodecyl sulphate poly acrylamide gel electrophoresis. AH the isolates showed marked variations among themselves and between fluorescent and non-fluorescent groups. However, similarity was observed with respect to three protein bands with molecular weight of 46, 43 and 32kDa. Data were scored based on the presence or absence of protein bands and cluster analysis was performed. The isolates from same location viz ., Coimbatore (PF1, PB2, COP1 and COT1), Sankaran Kovil (PSK1 and PSK2) and host (rice) showed greater level of similarity and occupied same cluster groups.

Identification of a Serratia marcescens Strain and Bioassay Against Oedaleus infernalis Saussure

Abstract: A pathogen was isolated from natural dead insect of Leucania separata. It produced aubergine pigment. According to its physiological and biochemical properties, it was identified as Serratia marcescens HBZBS 1. Its serotype was O 6. The preliminary bioassay showed that this strain exhibited potent larvicidal toxicity against Oedaleus infernalis Saussure. The mortality was above 80% for 4 d after infection.

Compatibility of Thiamethoxam with Trichoderma harzianum

Abstract: Laboratory experiment was conductcd to study the compatibility of 1 hiamethoxam 70WS with growth and sporulation of Trichoderma harzianum . There wn no inhibition of mycelial growth of T. harzianum in all the concentrations except at 1.25 percent. The spore count was 1xl0 4 spores/ ml at seven days after inoculation of Trichoderma . The reduction in the radial growth of Rhizactonia solani was 40.2 percent in presence of T. harzianum whereas no inhibition was observed In thiamethoxam at 10g/kg seed. In combination with thiamethoxam at 2,85g/kg seed+ Trichoderma , 4.28g/kg seed+ Trichoderma and l0g/kg seed+ Trichoderma , the reduction in radial growth of R. solani was 37,3, 35,95 and 32.4 percent, respectively. The study indicated that it is possible to use Trichoderma @ 4g/kg seed and thiamethoxam l0g/kg seed as seed treatment, which find a place in the integrated insect pest and disease management.

The Biology and Host Range of Water Hyacinth Weevil,Neochetina eichhorniae,an Insect Agent for the Control of the Weed

Abstract: The water hyacinth weevil, Neochetina eichhorniae was originally introduced from Argentina into China in 1995. The adult preferred to attack younger leaves and fed on the epidermal layer and the underlying cells and left a lot of "feeding scars" on the leaves. The longevity of the adult was between 29 and 161 d with an average of 104 d. The female laid 84-1091 eggs during this pariod. The larvae tunneled inside the petiole and crown of the host plants, and completed their growth in 30-40 d, then pupated underwater attaching to living roots of the floating plants. Pupae required 25-30 d for development. Two overlapping generations occurred in a year in Wenzhou. Host range tests with 46 plant species from 23 families showed the weevil only attacked and completed its life cycle on water hyacinth in choice and no choice tests, indicating that the weevil could safely be used to control water hyacinth in China.

Effect of Additives on Bacillus thuringiensis for Controlling Plutella xylostella

Abstract: Chemical additives have been used to enhance the activity of Bt against Plutella xylostella Chemicals of various groups were assessed with respect to their effect in increasing the activity of fermentative liquid of Bt Using leaf dip bioassay, preliminary screened 82 chemical additives including inorganic salts, organic acids, aromatic compounds, protein solubilizing agents, nitrogenous compounds The result indicated that some additives were able to increase the efficacy of Bt at certain concentration The chemical compounds, borax, potassium carbonate, sodium ethylene diamine tetracetate, calcium acetate, resorcinol, magnesium chloride, sodium benzoate, sodium acetate and ferrum (Ⅱ) sulphate were found to increase the activity of Bt by 27817, 20900, 09905, 09774, 04378, 07648, 07397, 04513, 0 5495 times, respectively

Peroxidase and Chitinase Activities in Brinjal Inoculated with Meloidogyne incognita (Kofoid & White) Chitwood and Endomycorrhiza

Abstract: Studies were conducted to observe the development of peroxidase and chitinase activity in brinjal cv.Co-2 inoculated with Vesicular arbuscular mycorryzae (VAM) and the root knot nematode, Meloidogyne incognita . Peroxidase activity was increased and a decrease in chitinase activity was observed which is a defense mechanism of the host lo invading pathogen.

Efficacy of Trichoderma viride Pers. Gray and Neem Cake Amendment in Different Soils against Blackgram Root Rot Caused by Macrophomina phaseolina (Tassi.) Goid

Abstract: Studies were conducted in a greenhouse to assess the efficacy of Trichoderma viride Pers. Gray and neem cake in different problems soils viz ., sandy, black hard pan, saline, sodic, alkaline, red crusted soil, acid soil and normal soil in suppressing the growth of blackgram root rot pathogen Macrophomina phaseolina (Tassi.) Goid. The biocontrol efficacy of T. viride I 3 , plus neem cake application in uninfested soil was the maximum 60 days after inoculation in acid soil which showed the minimum (5.63%) root rot incidence as compared to T. viride I 3 , alone (6.44%) and neem cake application alone (7.15%). In infested soil, the T. viride I 3 and neem cake plus pathogen inoculation recorded the minimum (6.47%) disease incidence in acid soil as compared to T. viride I 3 , and pathogen inoculation (7.52%), and neem cake application plus pathogen inoculation (8.72%), In uninocuiated control and in inoculated control of acid soil, the root rot incidence was 7.84 and 9.70 percent, respectively.

Selection of Antagonistic Strains Against Watermelon Wilt and Their Biocontrol Efficiency

Abstract: antagonistic Trichoderma spp. and 10 bacterial isolates against the pathogenic Fusarium oxysporum f. sp. niveum were isolated and selected from hundreds of soil and plant roots samples. Among the strains, Trichoderma viride TR 8 and Bacillus sp. B67 were the most effective ones and fermented to prepare their inocula and their mixture named Jiangenbao. Inoculation tests in greenhouse showed that all the biocontrol agents had good control effectiveness for control of watermelon wilt disease. Jiangenbao dust was more effective than its rwo constituents used alone. In field trials, when Jiangenbao dust diluted with soil at the ratio of 1∶50 was applied into seed delves before sowing, 80% control effect against watermelon wilt was obtained, which was apparently higher than that of carbendazim and amino oligosaccharin. Furthermore, it was also observed that Jiangenbao dust could enhance watermelon plant growth.

Nutritional influence of prey on the biology and biochemistry in Rhynocoris marginatus (Fabricius) (Heteroptera: Reduviidae)

Abstract: Nutritional influence of three prey species namely Spodoptera litura (Fabricius), Raphidopalpa foveicollis Lucas and Chrotogonus sp. on the biology and biochemistry of Rhynocoris marginatus (Fabricius) was examined in the laboratory at 30±2°C, 75-80 percent relative humidity and 11-13h photoperiod. Newly emerged nymphs were reared singly on the three prey species separately and followed through all life stages until the predator died. Developmental period of nymphs was longer on R. Foevicollis (100.08±9.06 days) than on Chrotogonus sp. (85.52± 10.14 days) and minimum developmental period was recorded on S.litura (69.36±6.75 days). Maximum fecundity and longevity was recorded on S. Litura fed category. The biochemical constituents such as carbohydrates, proteins and lipids were also higher in S.litura fed R. marginatus .

Applying Amino-oligosaccharin on Tobacco for Controlling Tobacco Virus Disease

Abstract: Amino oligosaccharin was applied on tobacco to control tobacco virus diseases. The results indicated that amino oligosaccharin could control TMV and CMV evidently. The control effect was better on CMV than on TMV, and the control effect for CMV was 34 92% in greenhouse and 64 9% in field. After treating with amino oligosaccharin,the concentration of proline increased and the concentration of MDA reduced.

The Effect of Oligochitosan on the Activity of Defensive Enzyme and Zymogram of Isoenzyme in Tobacco Leaves

Abstract: The physiology and biochemistry resistance of induced by oligochitosan in tobacco to combat against TMV infection were studied. Tests on some defensive enzymes indicated that the activity of peroxidase (PO), catalase (CAT), polyphenoloxidase (PPO), phenlalanine ammonialyase (PAL) and β 1.3 glucanase in tobacco leaves increased after treatment with oligochitosan. Spraying oligochitosan could result in 7 bands of PO isoenzyme in leaves. So it was preliminarily considered that the induced resistance of oligochitosan in tobacco to resist against TMV was closely related to the activity and zymogram type of PO isoenzyme. There was no correlation between the activity of SOD, CAT or PPO and the induced resistance. Activity of PAL and β 1.3 glucanase was clearly increased after spraying oligochitosan or inoculating TMV, but the cumulative response of the two factors was not clear.

Influence of some ions on biocontrol system of soybean cyst nematode

Abstract: In laboratory test, influence of 6 ions (Mo 6+ ,B 3+ ,Zn 2+ ,Cu 2+ ,Mn 2+ and Fe 2+ ) on hatching of eggs of SCN, germination of seed and growth of germ roots of soybean, and hyphal growth of the fungus, Verticillium chlamydosporium, the biocontrol agent of SCN was investigated. The results showed that: Zn 2+ could stimulate hatching of eggs of SCN. Cu 2+ , Mn 2+ and Fe 2+ decrease hatching. The latter three ions appeared to inhibit germination of seed and growth of germ roots of soybean. However, they did not affect the growth of soybean continuously. Under lower concentration, the above three ions did not influence the hyphal growth of V. chlamydosporium. Cu 2+ could be applied as a supplement to the biological control formulation.