Wyniki wyszukiwania - AGRO

1

Impact of strains of entomopathogenic fungi on some main groups of soil microorganisms

100%

Draganova S., Donkova R., Georgieva D.

Journal of Plant Protection Research

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2008

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tom 48

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nr 2

169-179

The influence of entomopathogenic fungal strains - one Metarhizium anisopliae (Metsch.) Sorok. and seven Beauveria bassiana (Bals.-Criv.) Vuill. on some main groups of soil microorganisms was studied after introduction of their conidia into the soil. The soil samples were analyzed for densities of bacteria, actinomycetes and fungi by decimal dilutions of soil suspensions grown on selective media. The presence of conidia of fungal strains in the soil after a month from introduction was proved by bait method. Three of the strains of B. bassiana were established to be of the highest persistence, this being expressed by mortality of Galleria mellonella L. (Lepidoptera, Pyralidae) larvae from 70% to 90%, followed by strains 224Re of B. bassiana and 31 of M. anisopliae. The obtained results showed that examined strains of the entomopathogenic fungi manifested different in manner and varying in degrees of impact on density of the main groups of soil microorganisms. Relatively insignificant changes were established under the influence of the strains 224Re B. bassiana and 31 M. anisopliae. The other strains of B. bassiana caused alterations in microbial balance expressed in different manner - stimulation or suppression on density of free-living nitrogen-fixing microorganisms, mineral nitrogen utilizing bacteria, spore-forming bacteria, cellulose degrading microorganisms, actinomycetes, soil fungi. So each strain could be characterized by specific impact on examined groups of soil microorganisms. The strain 412 of B. bassiana showed the most strongly manifested stimulation effect on the heterotrophic microorganisms, on the mineral nitrogen utilizing bacteria, on the free-living nitrogen-fixing microorganisms and the soil fungi - 14, 15, 7 and 30 times higher density of the microorganisms compared to the control treatments. The same strain caused high degree of suppression on densities of cellulose degrading microorganisms - 0.0064 x 106 compared to 0.0305 x 106 CFU/g in the control treatment. Densities of the soil spore-forming bacteria were not affected by the examined strains of B. bassiana and M. anisopliae. In the conducted experiments it has been established that the manifested impact on actinomycetes density by strains of the entomopathogenic fungi B. bassiana and M. anisopliae was different in manner and varying in degrees, on the contrary to the stimulation influence on density of the soil fungi.

2

Influence of some inert diluents of neem kernel powder on protection of sorghum against pink stalk borer [Sesemia calamistis, Homps] in Nigerian Sudan savanna

100%

Okrikata E., Anaso C.

Journal of Plant Protection Research

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2008

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tom 48

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nr 2

161-168

Neem (Azadirachta indica) kernel powder (NKP) mixed 1:1 (weight basis) with some inert diluents (fine-sand, kaolin-dust, and saw-dust) were applied into the whorls of sorghum seedlings at 20, 30, 40, 50, days after sowing to provide protection against pink stalk-borer in field trials in 2002 and 2003. Carbaryl (Sevin 85) and untreated seedlings were used as check. Results showed that diluted NKP and carbaryl significantly (p ≤ 0.01) reduced leaf puncturing, dead hearts, stalk and peduncle boring below the untreated check. Although sole NKP caused scorching of leaves (phytotoxicity), this was not observed on plants treated with diluted NKP and absent with carbaryl. Mean yield increases above the untreated check for the two seasons were: 40.0% (NKP + fine-sand), 36.4% (NKP + kaolin-dust), 35.5% (sole NKP), 35.3% (NKP + saw-dust) and 29.4% (carbaryl). Cost-benefit analysis shows that it was financially most beneficial to use NKP + fine-sand to control S. calamistis on sorghum in Nigerian Sudan savanna.

3

Effectiveness of azoxystrobin in the control of Erysiphe cichoracearum and Pseudoperonospora cubensis on cucumber

100%

Anand T., Chandrasekaran A., Kuttalam S. P., Senthilraja G., Raguchander T., Samiyappan R.

Journal of Plant Protection Research

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2008

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tom 48

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nr 2

147-159

The bioefficacy of azoxystrobin (Amistar 25 SC) was tested against cucumber downy mildew and powdery mildew diseases. The two season trials of field studies revealed that the disease progression of cucumber downy mildew and powdery mildew was successfully arrested by azoxystrobin. Spraying of azoxystrobin at various doses (31.25, 62.50 and 125g a.s./ha) revealed that 125 g a.s./ha (500 ml/ha) was considered as the optimum dose for the control of these diseases of cucumber. The treatment also recorded the highest yield of 13.23 and 14.46 tonnes/ha in the first and second season, respectively. No phytotoxic effect of azoxystrobin was observed in the both field trials even at four times of the recommended dose 125 g a.s./ha. The persistence of azoxystrobin at 250 and 500 g a.s./ha was observed up to seven days after last spraying. However, the persistence of azoxystrobin at 31.25, 62.50 and 125 a.s./ha was observed up to three to five days after last spraying. The safe waiting period for the harvest of cucumber fruits was 1.53 days in the first field trial and 2.37 days in the second field trial, respectively at azoxystrobin 125 g a.s./ha. The residues of azoxystrobin were at below detectable level (BDL) in the harvested cucumber fruits.

4

Mycoflora associated with decomposition of rice stubble mixed with soil

100%

Pandey V., Sinha A.

Journal of Plant Protection Research

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2008

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tom 48

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nr 2

247-253

Fungi inhabiting rice stubble mixed with soil were isolated by dilution plate technique. Moisture content of decomposed rice stubble mixed with soil was 25.32% in the month of August and minimum (5.35%) in the month of April and pH varied between 6.8-7.2. The highest (47.68 x 104) fungal population in 1 g of rice stubble mixed with soil was recorded in the month of October and the lowest (16.88 x 104) in the month of May. A total of twenty-nine fungal species were recorded during the entire period of decomposition. Dueteromycetous fungi constituted 75.86 per cent of total fungal population followed by zygomycetous, oomycetous and ascomycetous fungi. Monthly variation in fungal population was correlated with substrate availability and climatic factors. Dominance of Rhizopus stolonifer, Aspergillus flavus and Trichoderma harzianum was recorded during the decomposition while Pestalotia mangiferae, Torula graminis and Alternaria solani were obtained as rare fungal species.

5

The occurrence of pathogenic fungi during flax growing season in Central Lithuania

100%

Gruzdeviene E., Brazauskiene I., Repeckiene J., Lugauskas A.

Journal of Plant Protection Research

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2008

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tom 48

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nr 2

255-265

Experiments designed to study the variation of diversity of pathogenic fungi occurring in fibre flax agrocenosis during the growing season were conducted at the Lithuanian Institute of Agriculture Upytė Experimental Station during 1999-2002. The Upytė Experimental Station is situated in Central Lithuania. Phytopathological analyses of seed, soil and plants were done at the laboratory of the Upytė Experimental Station as well as at the Biodestructor Research Laboratory of the Institute of Botany. There were identified in the rhizosphere 9 fungal species belonging to 9 genera. On flax seedlings were identified fungi belonging to 13 genera. On flax leaves at green maturity stage was identified only Oidium lini. On flax stems at green maturity stage were identified fungi belonging to 12 genera. On mature flax stems were found fungi belonging to 15 genera. On flax seed during the experimental years were identified fungi belonging to 16 genera. The number of fungi identified on seeds varied each year, depending on the year's weather conditions during the seed ripening period. Having summarised the results, we can assert that pathogenic fungi Fusarium spp. and Colletotrichum lini, were found both on seed and plant vegetative parts during the whole assessment period. Species composition of fungi present on seed differed depending on the weather conditions. A larger number and more diverse species were found on the seed that ripened during the years with wet growing seasons (2000 and 2001) whereas the seed that ripened during dry growing seasons (1999 and 2002) was less infected with fungi. The spread of fungi on stems and leaves was also determined by the weather conditions. Many species of fungi were identified in 2001, when flax crops were lodged; stems and capsules were damaged by hail, and in 2000, when there was much rainfall.

6

Population dynamics of sugar-beet cyst nematode [Heterodera schachtii] on spring and winter oilseed rape crops

100%

Dobosz R., Kornobis S.

Journal of Plant Protection Research

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2008

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tom 48

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nr 2

237-245

The influence of spring as well as winter oilseed rape on the change in population density of H. schachtii was investigated in microplot experiment in the years 2002-2005. The spring oilseed rape caused the increase of nematode population (Pf/Pi were 1.31-1.79), in contrast to winter oilseed rape where the population distinctly decreased (Pf/Pi were 0.49-0.59). No statistically important differences between winter oilseed rape crops and fallow were observed. Comparative observations of the life cycle were carried out in pot experiments outdoors. On spring oilseed rape only one generation was completed. The development of the second generation was interrupted because of crop harvesting. In winter oilseed rape J3 and J4 occurred in roots in the autumn where they probably did not over-winter, except of the years 2006-2007. In the spring there was a second emergence of larvae and adult females were observed in June and July. The development of the second generation was interrupted because of harvesting. In winter oilseed rape sown in the spring one generation was completed.

7

The effect of leaf colour of selected field bean cultivars which differ in attracting black bean aphid [Aphis fabae Scop.]

100%

Wiwart M., Sadej W.

Journal of Plant Protection Research

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2008

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tom 48

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nr 2

195-200

The study was carried out in 2003, in a micro-plot experiment established in the Experimental Garden of the University of Warmia and Mazury. Following our previous long-term field observations on the infestation of a number of field bean cultivars by black bean aphid, three cultivars were selected for the present study. The cultivars demonstrated different attractiveness to the pest insects: cultivar Tinos was preferred by aphids, cv. Dino was less readily chosen and cv. Nadwiślański was the least preferred variety. The computer analysis of leaf colour enabled us to distinguish between the cultivars. The three examined cultivars are different in the colour of leaves, although the differences between cv. Dino and Nadwiślański being nearly negligible, especially in terms of hue (H) and intensity (I).

8

Antagonistic effects of Trichoderma species in biocontrol of Armillaria mellea in fruit trees in Iran

100%

Asef M. R., Goltapeh E. M., Danesh Y. R.

Journal of Plant Protection Research

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2008

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tom 48

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nr 2

213-222

Root and butt rot caused by species of Armillaria is one of the most serious diseases of fruit and forest trees in Iran. In this study, antagonistic effects of Trichoderma in biocontrol of Armillaria were investigated. Armillaria mellea was isolated from infected roots and butts of cherry and almond trees and identified with pairing tests method. Trichoderma species were recovered from rhizomorphs and around soil of Armillaria infected roots. Trichoderma species identified were T. virens (nine isolates) and T. harzianum (three isolates). Trichoderma discs were placed onto cultures of Armillaria to study antagonistic effects. All isolates of Trichoderma colonized Armillaria colonies within 5-7 days. Volatile compounds of Trichoderma isolates inhibited Armillaria colony growth and rhizomorph formation. Mechanisms of biocontrol were investigated by light and scanning electron microscopy, these included penetration of Trichoderma hyphae in rhizomorphs, colonization of rhizomorphs by Trichoderma mycelia, colonization of apex meristemic center and apical buds of rhizomorphs, sporulation of Trichoderma in outer and inner surface of rhizomorphs, degeneration and lysis of rhizomorph tissue, and discharge of rhizomorph content.

9

Interaction of root-knot nematode [Meloidogyne javanica] and tomato as affected by hydrogen peroxide

100%

Karajeh M. R.

Journal of Plant Protection Research

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2008

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tom 48

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nr 2

181-187

The effect of hydrogen peroxide (H2O2) on root-knot nematode (RKN, Meloidogyne javanica) in tomato was investigated. Soil drenching with exogenous H2O2 was done using seven H2O2 concentrations (1, 10, 100, 250, 500, 750 and 1000 mM) at different application times (24 hours before the time of plant inoculation with the RKN (T1), at the time of inoculation (T2), and 24 hours after the inoculation time (T3). The nematode reproduction rate (eggs/g fresh root) was significantly reduced in all H2O2 treatments compared with the untreated control. The lowest reduction in nematode reproduction occurred at 10 mM H2O2. The application times T1 and T2 were significantly higher in reducing the reproduction rate than T3 at 250, 750 and 1000 mM H2O2. The content of endogenous H2O2 in the treated plants was significantly higher than in the non-treated plants. Some phytotoxicity was apparent at the higher concentrations of H2O2 (≥ 500 mM) in the treated plants due to the accumulation of the endogenous H2O2. The treatments with 1 and 10 mM H2O2 did not differ from the untreated control in plant chlorophyll content while the content was significantly reduced at the higher concentrations. Exogenous application of H2O2 may have a direct effect on the nematode reproduction and an indirect effect on the treated tomato plants that can be elicited by H2O2 to resist the nematode infection.

10

Gregarina vizri Lipa, 1968 [Apicomplexa: Eugregarinida] recorded in Poland i an expansive plant pest the cereal ground beetle Zabrus tenebrioides [Goeze] [Coleoptera: Carabidae]

100%

Sienkiewicz P., Lipa J. J.

Journal of Plant Protection Research

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2008

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tom 48

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nr 2

189-193

An eugregarine Gregarina vizri Lipa, originally recorded and described from the cereal ground beetle [Zabrus tenebrioides (Goeze)] collected in the Chechnya-Ingushetia (Russian Federation), is reported from the same host insect in Poland. Out of 45 examined adult beetles 19 were parasitized. Morphometric analysis of G. vizri trophozoites and gamonts observed in the digestive tract of host specimens originating from Russian Federation and from Poland showed a significant similarity.

11

Effect of fungicides on colony growth of Colletotrichum lindemuthianum [Sacc. and Magn.] Scrib

100%

Sartori J. E., Maringoni A. C.

Journal of Plant Protection Research

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2008

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tom 48

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nr 2

201-212

Colletotrichum lindemuthianum (Sacc. & Magn.) Scrib. is the causal agent of the anthracnose of common bean (Phaseolus vulgaris L.), a fungal disease of a great significance in brazilian bean cultures. The goals of this work were to evaluate the in vitro colony growth and to determine the ED50 interval of twenty C. lindemuthianum isolates from different regions of Brazil to five fungicides of different active ingredients and to some blendings (carbendazim, chlorothalonil, thiophanate-methyl, chlorothalonil + thiophanate-methyl, trifloxystrobin, propiconazole and trifloxystrobin + propiconazole), at concentrations of 0, 1, 10, 100 and 1000 μg/ml, in a potato-dextrose-agar culture medium. The results revealed seven isolates with low sensitivity to carbendazim and thiophanate-methyl (ED50 interval greater than 1000 μg/ml) thus suggesting cross-resistance. Isolate sensitivity to chlorothalonil ranged from ED50 interval less than 1 μg/ml to greater than 1000 μg/ml. Those isolates with high sensitivity to thiophanate-methyl, ED50 interval less than 1 μg/ml, did also show it with respect to chlorothalonil + thiophanate-methyl. Sixteen isolates showed a high sensitivity to trifloxystrobin with a ED50 interval less than 1 μg/ml. Nineteen isolates of C. lindemuthianum showed high sensitivity to propiconazole and to trifloxystrobin + propiconazole with ED50 interval less than 1 μg/ml. Isolates with low sensitivity to carbendazim and thiophanate-methyl were sensitive to propiconazole and to trifloxystrobin + propiconazole. Variability was found in the sensitivity of the colony growth of C. lindemuthianum isolates from different regions of Brazil to the fungicides evaluated.

12

Occurrence of soilborne diseases and root knot nematodes in strawberry plants grown on compacted rice straw bales compared with naturally infested soils

100%

Abdet-Sattar M. A., El-Marzoky H. A., Mohamed A. I.

Journal of Plant Protection Research

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2008

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tom 48

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nr 2

223-235

The present investigation deals with a possible use of rice straw bales as "soilless" cultivation medium, thus escaping the problems inherent in the natural soils and avoiding a serious pollution when disposed about 5°C million tons of rice straw annually by burning. Strawberry fruits of good quality and quantity were harvested from plants cultivated on compacted rice straw bales in comparison with the control plots under natural soil conditions. A higher temperature of 2 to 5 in comparison to natural soil conditions favours all physiological activities including the absorption of nutrients by roots and thus stimulating the vegetative and the generative growth of strawberry plants. The pH values around the roots in straw bales ranged from 5.5 to 6.5, while values obtained around the root system in natural soil ranged from 7.5 to 8.5. So, growing strawberry on rice straw bales helps avoid and overcome the problem of alkalinity and salinity in the rhizosphere. This is very important, as strawberries are very sensitive to salinity. Fruit rot diseases reached 0.8% on rice straw bales while on the control plots these were about 52% of fruits were infected with fungi. Cultivating strawberry on rice straw bales keeps the fruits away from contacting the soil and thus limits the possibility of injection by soilborne fungi. The occurrence of damping-off, root rot, crown rot and root knot nematodes in strawberry plants grown on rice straw bales reached 4.0, 0.85, 0.35 and 0.0%, respectively. However, the corresponding figures for strawberry plants grown in natural soil under the same conditions were 27.0, 16.15, 11.70 and 13.20%, respectively, 135 days after planting. Isolation from strawberry plants grown in natural soil showing symptoms of crown rot and black root rot yielded several fungi identified as Phytophthora cactorum, Colletotrichum fragariae, Pythium ultimum, Rhizoctonia solani and Fusarium oxysporum. The wilt symptoms observed on few strawberry plants on rice straw bales might be attributed to very sporadic contamination with soil particles or through irrigation water. Based on the above results, it could be recommended using rice straw bales as growing media to replace naturally infested soil, this can improve the production of strawberry under open field conditions in Egypt. Also, it is important to avoid the serious pollution when disposed rice straw by burning.

13

Comparison of infection caused by Pythium debaryanum, Phytophthora palmivora and Erwinia caricae on transgenic and non-transgenic papaya ringspot virus resistant plants

100%

Cumagun C. J. R., Padilla C. L., Tolentino M. S., Hautea D. M.

Journal of Plant Protection Research

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2008

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tom 48

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nr 2

137-145

The study was conducted to determine the reaction of transgenic papaya ringspot virus (PRSV) - resistant papaya to some major fungal and bacterial diseases of papaya. Four lines of transgenic papaya developed by the Institute of Plant Breeding (IPB) and non-transgenic ‘Davao solo’ were used in the screening. Plants were artificially inoculated with the most aggressive isolates in a contained greenhouse. Inoculation was done by incorporating Pythium debaryanum and Phytophthora palmivora - colonized wheat seeds into the base of the plant and by pricking the base of leaf petiole with a needle dipped in suspension of Erwinia caricae. Four transgenic papaya lines and ‘Davao Solo’ were susceptible to P. debaryanum and P. palmivora under greenhouse conditions. No significant differences in per cent wilted seedlings caused by P. palmivora among transgenic four lines and ‘Davao Solo’ were observed (p = 0.05). Similarly, no differences in root rot severity (%) among the same test plants due to P. palmivora were noted. The three transgenic papaya lines were initially more susceptible than ‘Davao Solo’ to E. caricae seven days after inoculation but the same degree of infection was attained 14 days after inoculation. The transgenic and the non-transgenic papaya exhibited susceptible reactions to P. debaryanum in the greenhouse. No significant difference was observed in one transgenic line and ‘Davao Solo’ in terms of pre and post germination damping-off incidence in inoculated soil (p = 0.05).

14

Rosliny energetyczne - nowe wyzwanie dla ochrony roslin

51%

Pruszynski S., Gacek E.

Progress in Plant Protection

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2005

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tom 45

|

nr 1

384-391

15

Ochrona maku

51%

Kedzior M.

Biuletyn Informacyjno-Handlowy. Ośrodek Doradztwa Rolniczego Boguchwała

|

1995

|

nr 05

5

16

Definicja, zalozenia i zasady ustalania stref wolnych od agrofaga [Pest-Free Area/FAO, 1995/]

51%

Wolny S.

Progress in Plant Protection

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1996

|

tom 36

|

nr 1

88-95

17

Problem pospolitych chwastow segetalnych Polski

51%

Latowski K.

Progress in Plant Protection

|

2002

|

tom 42

|

nr 1

392-399

18

Problems of plan conservation in north-western Poland

51%

Piotrowska H.

Zeszyty Naukowe Wydziału Biologii, Geografii i Oceanologii. Uniwersytet Gdański. Biologia

|

1986

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nr 07

19

Rewizja zasad Dobrej Praktyki Ochrony Roslin

51%

Wolny S.

Progress in Plant Protection

|

2002

|

tom 42

|

nr 1

159-165

20

Ekologiczne metody ochrony roslin

51%

Poprawska-Leska J.

Biuletyn Informacyjno-Handlowy. Ośrodek Doradztwa Rolniczego Boguchwała

|

2006

|

nr 07-08

24-25

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