Laboratory studies were carried out on the effects of an emulsifiable concentrate (EC) formulation of Azadirachtin (AZ) (6 g a.s./l EC) on four major cotton pests in Senegal: Spodoptera littoralis Boisduval (Lepidoptera: Noctuidae), Helicoverpa armigera Hϋbner (Lepidoptera: Noctuidae), Aphis gossypii Glover (Homoptera: Aphididae) and Tetranychus urticae Koch (Acari: Tetranychidae). In both S. littoralis (SL) and H. armigera (HA), larval weight loss was observed 48 h after treatment. Appreciable weight gain was only observed in SL larvae at dosages of 0.05 and 0.1 g a.s. /l AZ, 72 h after treatment. In both SL and HA, there was a significant difference (p < 0.05) between the control larvae and those treated with 0.1 to 1.5 g a.s. /l AZ. At a dosage of 1.5 g a.s./l, AZ caused 60% mortality in SL and 0% mortality in HA, 72 h after treatment. The treatment with AZ at dosages of 0.05 and 1.5 g a.s./l resulted in 50 and 30% malformation in SL and HA pupae respectively. The duration of development from the IV instar larva to pupa in both lepidopterans increased progressively with AZ dosage. SL was more susceptible to AZ than HA. No growth disrupting effects were observed in A. gossypii (AG) and T. urticae (TU) where EC50 values of 1.49 and 1.36 g a.s./l AZ respectively were obtained. The implications of the effects of AZ on further field trials against cotton pests are discussed.
Bacterial speck of tomato caused by Pseudomonas syringae pv. tomato appeared to be recently the most important disease on tomato in Poland. The genetic relationships among four Polish strains of race 0 P. syringae pv. tomato of different origin, isolated from tomato plants, were examined by RAPD and PCR-RFLP techniques. Amplification of bacterial DNA using 33 primers with RAPD technique showed, that similarity of strains expressed by the Nei-Li coefficient was very high (above 0.8). Next, the restriction analysis of amplified region ITS with the use of 5 endonucleases revealed, that profiles obtained from electrophoretic separation of DNA fragments were also very similar. On the basis of those analyses it was concluded that all strains tested constituted a closely related group. However, they showed various level of virulence as was demonstrated on the inoculated leaves of tomato plants growing in the greenhouse.
Three plant extracts viz. bulbs of Allium sativum L. (Liliaceae), seeds of Annona squamosa L. (Annonaceae) and leaves of Vitex negundo L. (Verbenaceae) were evaluated against cowpea wilt pathogen, Fusarium oxysporum f. sp. ciceris by mycelial dry weight method under laboratory condtions. The mean mycelium dry weights of F. oxysporum of methanol and benzene extracts of A. sativum obtained from 125 g of crused dry plant material (bulbs) were 0.0113 and 0.0174 mg, respectively. This was followed by methanol and petroleum ether extracts of A. squamosa (0.2396 and 0.2381 mg). They effectively controlled mycelial growth of cowpea wilt pathogen, however V. negundo extracts did not cause any significant mycelium growth inhibition when compared to other plant extracts tested. Among the three plant extracts, methanol extracts of A. sativum bulbs could possibly be used for controlling F. oxysporum.
A biotic interaction between fungi from soil within and outside the rhizosphere of potato and fungi responsible for black scurf – Rhizoctonia solani Kühn and silver scurf – Helminthosporium solani (Dur., Mont.). It was found that fungi population connected with crop environment under investigation promoted the growth of Rhizoctonia solani, thus indicating no resistance of this environment to this pathogen. These fungi, however, inhibited the growth of Helminthosporium solani.
The aim of presented investigation was to determine the composition of scale insects species and intensity of their occurrence on some greenhouse’s ornamental plants. The investigations were carried out in the greenhouse of Maria Curie Skłodowska Botanical Garden in Lublin in years 2002–2004. Eight species belonging to seven botanical families were observed: Abutilon striatum cv. Thomsoni, Cyrtomium falcatum Presl., Dizygotheca elegantissima (Veitch), Hedera helix L., Hypoestes phyllostachya Presl., Nerium oleander L., Passiflora guadrangularia L., Ruscus aculeatus L. The quantitative analysis of the studied material was performed making use of the following ecological indicators: number and density. Identification of the scale insects species was performed on the basis of microscope slides. Three species of the scale insects belonging to three families were observed on ornamental plants: Pseudococcidae [Pseudococcus maritimus (Ehrh.)], Coccidae [Saissetia coffeae (Walker)] and Diaspididae (Aspidiotus nerii Bouchè). The scale insects were noted on all species of studied plants. Observed scale insects are typical polyphagous and all of them are considered as harmful pests in greenhouses. Among scale insects inhabiting this group of plants distinctly numerous on particular host plants were S. coffea and A. nerii. On the studied plants scale insects were stated at four degree of density.
The purpose of the study, carried out in the years 2001–2003 was to determine which fungal species inhabited decaying grapevine cuttings during callusing and soon after planting them into pots. The plant material was collected from 5 commercial plantations and 8 cultivars, which were most frequently cultivated. From each plantation and cultivar 20 cuttings with symptoms of the growth inhibition or decay were randomly sampled during the callusing period i.e. March/April (term I) and 2–3 months after planting the cuttings into pots i.e. June/July (term II). The results showed that from affected grapevine cuttings Phomopsis viticola, Botrytis cinerea, Alternaria alternata and Fusarium spp. were isolated most frequently. Moreover, it was found that after planting young cuttings into the pots, numerous isolates of soil borne pathogenes were obtained, among others Cylindrocarpon spp., Phytophthora sp., Rhizoctonia solani, Fusarium spp.
The subject of this study was Rhizopertha dominica F. population. The primary question referred to was the process of the lesser grain borer population spread depending on nutritional preferences of this species. The aim of performed laboratory experiments was to examine the adults’ ability to choose preferred kinds of food i conditions of free migration among them and to analyze the dynamics of population size. Sex ratio and the migration rate were also analyzed. Four types of food were used during the experiments: wheat, oat flakes, pearl barley and semolina. The experiments were conducted at 28°C and 60 ± 5% of relative humidity. Results of the study revealed that oat flakes were the most favourable nutriment for adult R. dominica whereas wheat grain was the most favourable for the population size since larvae were protected by grains and thus their increased number could survive. No population development in semolina was observed. It was the result of too small granulation of this food.
The subject of this study was the lesser grain borer Rhizopertha dominica F. The aim of the experiments was to verify the hypothesis suggesting that the course of simultaneous vertical migration and horizontal spread of the R. dominica population is determined by nutritional and habitat selectivity. The following products were used as nutrients in the experiments: wheat, oat flakes, pearl barley and semolina. It was found that the course of a migration process is connected with nutritional preferences determined mainly by a nutrient type and its granulation. At the initial stage of the study the highest emigration was noted in the oat flakes. After a time the highest migration was directed to as follows: wheat, oat flakes, pearl barley and semolina. Females showed a higher migratory activity.
The subject of the performed experiments comprised standard XR 110 02, XR 110 04 nozzles, TT 110 02, TT 110 04 nozzles and AI 110 02, AI 110 04 air induction nozzles. The working speed of spraying was vp = 7 km/h. Each nozzle was tested at the following three levels of working pressures: p1 = 0.2 MPa, p2 = 0.4 MPa ad p3 = 0.6 MPa. The spray liquid was pure water at the temperature of 20°C. The plant coverage was determined: sk – spray coverage, nk – number of droplets per 1 cm2. The analysis of results of maize spraying showed that both standard nozzles and both TT nozzles achieved better results with number of droplets and degree of surface coverage for each of applied operating pressure. The lowest results from all examined kind of nozzles for number of droplets achieved injector nozzles (AI). For operating pressure 0.4 MPa nozzles fulfilled agrotechnical requirements for using insecticids, herbicides and fungicides.
The experiments were carried out in 2001–2004. The aim of the research was to establish such chlorsulfuron dose that would be effective for Apera spica-venti control and would not be phytotoxic for winter wheat. Besides, it was performed to identify resistance of A. spica-venti biotypes appearing in the experimental fields to chlorsulfuron. The field experiments were conducted in winter wheat that were notably of A. spica-venti weedy. The fields belonged to a private farm at Karczyce and Gałów. The cereals had grown there for a long time and winter wheat monoculture together with repeated chlorsulfuron application was used. The experiments were conducted using randomized blocks method with 3 reapplications. Chlorsulfuron (Glean 75 WG) was applied at rates ranging from 1 to 4.5 times higher than the recommend field dose (15–67.5 g a.s./ha). The degree of sensitivity of A. spica-venti to chlorsulfuron was established by biological tests in greenhouse conditions. The herbicide was applied at four – leaf stage of development at rates ranging from 1 to 32 times higher than the recommend field dose (11.25–360 g a.s./ha). Poor chlorsulfuron efficacy to control of A. spica-venti or its lack might testify for resistance of this species to the herbicide. Chlorsulfuron as an active ingredient was very selective for winter wheat. An application of 67.5 g/ha of the herbicide was not harmful to growth and yielding of winter wheat. Unfortunately, even this dose of the herbicide was ineffective in control of A. spica-venti. In fields with a long-term monoculture of winter wheat together with the use of chlorsulfuron, resistance of A. spica-venti biotypes to this active ingredient was ascertained. Studies in greenhouse conditions proved that the biotypes were not damaged even when the dose was exceeded 32 times. The above confirmed the resistance of these biotypes to chlorsulfuron.
Cephus fumipennis Eversmann is a key insect pest of wheat crops in Qinghai, China. Its field population densities were surveyed by using both the back-loaded insect vacuum and a sweep net. Mean densities in township-level were calculated and a quantitative relation, ŷ = 0.664 + 0214x, was established between the two sampling methods. The empirical relationship may be applicable in density monitoring and Integrated Pest Management program of the insect.
Globodera artemisiae (Eroshenko et Kazachenko, 1972) was found in Poland in autumn of 2004. The nematodes developed on Artemisia vulgaris L. Morphological and morphometric characteristics of the Polish population correspond to earlier known populations from Far East of Russia, Armenia, China, Germany and Sweden. The traditional identification was confirmed by molecular methods. On the basic of rDNA sequences of G. artemisiae, deposited in GenBank the product of expected size was obtained. Subsequently, the results were confirmed by sequencing analysis.
In the vicinity of copper foundry “Głogów” agricultural farms exist for 35 years. The aim of the work was to determine if biotypes of common lambsquarters (Chenopodium album L.) growing for many years in heavy metals polluted environment showed any differences in the efficacy of herbicides’ control. Seeds of C. album were collected near Głogów, from four cultivated fields with different content of heavy metals in soil (mainly copper). From these seeds experimental plants were grown in greenhouse conditions. In greenhouse experiments the efficacy of control of C. album by different pyridate (6-chloro-3-phenylpyridazin-4-yl S-octyl thiocarbonate) doses also in combinations with 0.2% CuSO4 was compared. Also the efficacy of pyridate in control of C. album seedlings which were grown in pots with soils collected from the vicinity of smelter was tested. Additionally, in growth chamber, the effect of increasing copper concentration on shoot and root growth was analyzed. Pyridate showed similar efficacy on tested populations of C. album without respect of soil contamination level, seeds’ origin and presence of copper ions in spray solution in which herbicide was used in full dose. Statistical differences were observed when herbicide was applied at ⅓ pyridate full dose, especially in the presence of Cu2+ ions in spray solution.
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