Biological activity of 6 fungicides in the inhibition of Phytophthora ramorum sporulation and development of blight on rhododendron leaves and stems were evaluated. All tested compounds at dose 8 μg o fa.i./cm³ already inhibited zoosporangia formation at least in 73%. On leaf petioles and leaf disks, taken from rhododendron one week after treatment with fungicides, formation of chlamydospores was especially suppressed by fenamidone + phosetyl Al and oxadixyl + mancozeb whereas development o fspores was not inhibited by cymoxanil + famoxate. All tested compounds significantly inhibited the development and spread of twig blight on rhododendron. However, furalaxyl, applied as spraying of plants 48 hrs before or after inoculation of leaves and stems by P. ramorum was the most effective.

Investigation of leaf rust disease on spring crops of triticale (× Triticosecale Wittm.), it sdi stribution dynamics, as well as the efficacy of two fungicides, different application doses and timing was carried out at the Lithuanian Institute of Agriculture during 2000–2002. Differences in the disease development were determined by the meteorological conditions, especially the amount of rainfall, and growth stage of plants. Precipitation during 2000 was close to the mean, and the development of leaf rust was moderate. In June of 2001 the rainfall was twice as high as the norm, which created favourable conditions for pathogen development. In 2002 a long droughty period till flowering inhibited the development of leaf rust. The triazole fungicides Juventus (metkonazole 60 g l^–1) and triazole and strobilurine mixture. Allegro (kresoxim-methyl 125 g l^–1 + epoxikonazole 125 g l^–1) were used at full, two-third and half doses once and twice. Both of the fungicides were very effective against leaf rust. Biological efficacy of Juventus applied at any dose or time against leaf rust was 88.3%–99.7%. Allegro efficacy against this disease was slightly higher 94.7%–100%. Application of 1.0; 0.75 and 0.5 l ha^–1 doses twice showed a better efficacy than a single application. The higher doses of fungicides were not markedly superior to the lower ones.

The objective of the study was to determine the effect of leaf wetness period and air temperature on development of disease symptoms caused by Puccinia recondita on winter wheat. The experiments were carried out in growth chamber at the Institute of Plant Protection in Poznań. Seedlings of a susceptible winter wheat cultivar Mikon, were artificially inoculated with urediniospores of P. recondita and incubated in temperature of 15 and 20°C. The period of duration of leaf wetness varied from 2 to 14 hours. Disease symptoms on seedlings at 20°C appeared 7 days after inoculation. Reduction of temperature to 15°C resulted in the elongation of latency period to 8 days. The relationship between leaf wetness period and disease symptoms severity was also observed. The gratest number of urediniospores in both tested temperatures were observed on plants exposed to 14 hours of leaf wetness. In temperature of 20°C 4 hours of wetness duration was enough to guarantee infection and the appearance of P. recondita pustules, whereas in 15°C at least 10 hours of wet period was needed to cause disease symptoms development. The experimental results were used to produce two equations describing relation between leaf wetness and symptoms development in tested temperatures.

The effect of cercospora leaf spot caused by Cercospora arachidicola and Phaeoisariopsis personata on quality of groundnut haulm was assessed using official methods of analysis. The respective field experiments were conducted in 2004 and 2005 cropping seasons, while the laboratory analyses were carried out at the end of the seasons. The scale of 1–9 was used to determine severity of infection on randomly selected groundnut plants. The results showed that the year effect was not significant as related to haulm composition. However, severity of the disease was found to affect haulm composition either negatively or positively. Crude fibre, crude protein, fat and dry matter content of haulm were significantly lower in severely infected haulm samples compared to uninfected or less severely infected samples. While ash, moisture content and nitrogen free extracts (NFE) increased with increasing disease severity. The regression analysis showed that crude fibre, crude protein, fat and dry matter content were negatively related to cercospora leaf spot severity, while ash, moisture content and nitrogen free extracts showed positive relationship with increasing disease severity. Since infection by cercospora leaf spot pathogen lowers the quality of groundnut haulm, controlling the disease is necessary to ensure good quality of haulm at the end of the season.

Strawberry plants showing symptoms of leaf spots and petiole lesions were collected from El Qalubya governorate, which is one of the most famous areas that extensively grows strawberry in Egypt. The objectives of this study were to isolate and characterize the causal pathogen of the disease. The isolated pathogen was identified as Paramyrothecium roridum (formerly known as Myrothecium roridum) based on its morphological characteristics and sequencing the partial rDNA internal transcribed spacer (ITS). A pathogenicity test using detached leaf assay revealed that P. roridum is a potential pathogen of strawberry. Symptoms started as small necrotic areas which expanded rapidly to macerate whole leaflets and petioles. In advanced stages of infection, dark olive green sporodochia were clearly distinguished on the infected tissues. Six strawberry cultivars showed different levels of susceptibility to P. roridum. Florida was the most resistant cultivar while Beauty, Camarosa, Fortuna and Sweet Charlie were susceptible. Festival showed a moderate level of susceptibility. An in vitro assay on the effect of the liquid culture filtrate of P. roridum on strawberry leaves showed that the filtrate caused damage to tissues and clear necrotic symptoms were developed. High performance liquid chromatograph (HPLC) analysis on the filtrate of 10 day old P. roridum culture revealed the presence of various mycotoxins. The two major toxins detected were 8-alpha-hydroxyroridin H and myrothecin A in addition to other trichothecenes. Data also revealed the capability of P. roridum to produce polygalacturonase (PG) and cellulase (Cx) enzymes in liquid cultures. The activity of PG was found to be significantly correlated with the age of the growth culture. This is the first record of P. roridum on strawberry in Egypt.

This paper presents a comparative study on the anatomy of the Antarctic hairgrass (Deschampsia antarctica É. Desv.) from natural populations of two distant maritime Antarctic regions: the Argentine Islands (Antarctic Peninsula region) and the Point Thomas oasis (King George Island, South Shetland Islands). Comparison of D. antarctica plants from natural populations of Argentine Islands region and plants originated from seeds of these populations cultivated in vitro also was made. Additionally anatomical features of Deschampsia antarctica were compared with ones for D. caespitosa. The results of our study do not provide enough evidence to assert more pronounced xerophytic anatomical features in D. antarctica plants from more harsh conditions of Argentine Islands region. Such features (both qualitative and quantitative) of D. antarctica mainly depend on local conditions, and not on the latitudinal or climatic gradient. In both regions it is possible to find individuals that represent different ecotypes which are adopted to open arid or more humid habitats. It has been shown that Antarctic hairgrass plants germinated from seeds and cultivated in vitro retain the qualitative anatomy features that are typical to plants from the initial natural populations. This is especially noticeable in the case of plants from Berthelot Island (BE1 study plots), which might indicate a genetic fixation and a manifested differentiation similar to DNA haplotypes or chromosomal forms. However, quantitative characteristics, in particular the epidermis parameters, are subject to changes due to the transfer to more favourable conditions. Also qualitative and quantitative difference of D. antarctica in contrast with D. caespitosa have been described. These differences could be useful for identifying these two species. Additionally the quantitative differences (such as the area of the epidermal cells and the number and size of stomata on the adaxial surface) of Alaskan D. caespitosa grown from seeds were detected in contrast to the naturally grown plants of the same species from Ushuaia.

The sound absorption property of polyurethane (PU) foams loaded with natural tea-leaf fibers and luffa cylindrica (LC) has been studied. The results show a significant improvement in the sound absorption property parallel to an increase in the amount of tea-leaf fibers (TLF). Using luffa-cylindrica as a filler material improves sound absorption properties of soft foam at all frequency ranges. Moreover, an increase in the thickness of the sample resulted in an improvement of the sound absorption property. It is pleasing to see that adding tea-leaf fibers and luffa-cylindrica to the polyurethane foam demonstrate a significant contribution to sound absorption properties of the material and it encourages using environmental friendly products as sound absorption material in further studies.

Number of hairs on abaxial leaf surface of 13 apple cultivars differed significantly. The most hairs per 1 cm² on abaxial surface were on cvs. Lodel (2,578.3) and Jonafree (2,462.2). Leaves of cultivars Antonówka and Novamac had the least number of hairs (1,054.4; 1,285.7; respectively). Correlation between number of hairs on abaxial leaf surface of investigated apple cultivars and Tetranychus urticae (Koch) female fecundity decreased during 10 first days of their lives. Along with increased number of hairs, the fecundity of this species declined.

Field trails were conducted to evaluate the economics of controlling cercospora leaf spot of groundnut using different fungicides. The experiments were laid out in a strip plot design with three replications at the Teaching and Research farm of the Department of Crop Protection, University of Maiduguri, sudan savanna of Nigeria during the 2002 and 2003 cropping seasons. Four fungicides namely: Benlate 50 WP, Trimangol 80 WP, Bentex T, and Ridomil 72 WP were applied as foliar sprays at three spray regimes while the control was left untreated. The application of the fungicides led to 20–50% reduction in the disease incidence and 15–22% reduction in disease severity and gave higher yield of seed and haulm than the control. The cost-benefit analysis revealed positive returns per hectare from the use of the fungicides for the control of disease in the study area. Application of Bentex T, for instance, gave 78.13% seed yield increase over the control which translated into a mean (two years) net profit of N52,267.50, N90,905.00 and N138,755.00 Nigerian Naira for one, two and three sprays, respectively, equivalent to $522.675, $909.05 and $1,387.55 per hectare. Even the least effective of the fungicides (Trimangol 80 WP) gave seed yield increase of 62.74% over the control which translated into a mean (two years) net profit of N41,287.50, N68,082.50 and N93,995.00 equivalent to $412.88, $680.83 and $939.95 per hectare for one, two and three sprays, respectively. Three sprays gave 115. 76% increase of yield over one spray and 39.35% yield increase over two sprays. These returns are attractive particularly to the farmers in the study area who grow the high yielding Ex-Dakar groundnut variety which is susceptible to cercospora leaf spot.

The resistance of winter wheat varieties to Puccinia recondite f. sp. tritici was investigated at the Lithuanian Institute of Agriculture during 2001–2003. Effectiveness of resistance genes was investigated at seedling, tillering and adult plant stages. Virulence tests done during the 2000–2003 period showed that the majority of Lr genes used in European wheat were not sufficiently efficient. However, testing of cultivars at the first leaf stage revealed that the Lr37 gene in combination with the other genes was very effective. The experimental cultivars were sown in 2 times: in autumn and spring, without vernalization. The main task of spring-sown nursery was to improve the effectiveness of the experiment and investigate the effect of different Lr genes of non-vernalized plants at tillering growth stage. The Lr37 gene was found to be the most effective at both adult plant stage and tillering growth stage. Disease severity and plant resistance type at tillering stage were stable in all experimental years, which is important for the breeding program. The investigations revealed that the correlations between resistance at seedling and the other two stages were up to r = 0.81 (significant at p = 0.01**). The correlations between leaf rust severity and varietal resistance type at tillering were very high (r = 0.86–0.91**) in the same year. The correlation of leaf rust severity at adult plant stage was strong (r = 0.78**) between 2001 and 2002, but too low for reliable selection of resistant cultivars in the other years. Spring-sown nursery was complementary to collect resistance data in the years unfavourable for leaf rust development.

The efficacy of Benlate 50 WP (benomyl), Bentex T (benomyl + thiram), Ridomil 72 WP (metalaxyl) and Trimangol 80 WP (maneb) applied as foliar spray in the control of cercospora leaf spot of groundnut in the sudan savanna of Nigeria was evaluated during the 2002 and 2003 cropping seasons. Three spray regimes (once, twice and thrice per season) were evaluated. Strip plot design with three replications was used in setting up the experiments. Ex-Dakar, a cercospora leaf spot susceptible groundnut variety was used as planting material. All the four fungicides significantly reduced the incidence and severity of cercospora leaf spot in both seasons. However, the application of Bentex T significantly better reduced the incidence and severity of the disease than the other fungicides. This was followed by application of Benlate 50 WP. Ridomil 72 WP and Trimangol 80 WP which gave moderate control of the disease. Three sprays with fungicides gave better control of the disease than one or two sprays in the season. The highest seed yield of 1 716 kg/ha and 2 263 kg/ha in 2002 and 2003, respectively, were obtained following treatment with Bentex T. The lowest yield of 962 kg/ha and 1 270 kg/ha in 2002 and 2003, respectively, were recorded from the control plots. Also the highest seed yield of 2 028 kg/ha and 2 672 kg/ha in 2002 and 2003, were obtained following three sprays compared to 939 kg/ha and 1 239 kg/ha in 2002 and 2003, respectively, for one spray in the season. The highest haulm yield of 6 131 kg/ha and 6 722 kg/ha in 2002 and 2003 was recorded from plots treated with Bentex T compared to 4 752 kg/ha and 5 166 kg/ha in 2002 and 2003, respectively, obtained from the control. Haulm yield of 6 355 kg/ha and 7 027 kg/ha in 2002 and 2003 were obtained following three sprays compared to 5 088 kg/ha and 5593 kg/ha in 2002 and 2003, respectively, recorded for the control. Bentex Tor Benlate 50 WP could be used to reduce the effect of cercospora leaf spot and improve groundnut production in the sudan savanna of Nigeria.

Sixteen tomato cultivars obtained from the collections of the Institute for Agricultural Research (IAR) Samaru, Nigeria were screened for resistance to local strains of Tomato leaf curl virus at Samaru, Northern Guinea Savanna, over a two year period, 1998/1999 and 1999/2000 dry seasons. Five cultivars were moderately resistant, nine were moderately susceptible, while two were highly susceptible. Most of the cultivars were high yielding (46–55 t/ha) and had good fruit size (4.8–6.0 cm x 2.8–4.1 cm). They will be further evaluated on-farm at different locations after which they will be introduced to farmers to replace the low yielding and TLCV-susceptible cultivars currently in use in most parts of the Savanna ecological zones of the country.

This study investigated the quantitative anatomy of photosynthetic tissues (leaf mesostructure) of wild ginseng Panax ginseng C.A. Mey. (Araliaceae) plants from different natural habitats. The structural and functional traits of the photosynthetic apparatus shown to be especially elastic were mesophyll cell volume (Cv >40%) and traits related to filling of the leaf with cells and plastids (Cv≥21%). P. ginseng possesses relatively few cells per leaf area (44.6-107.2 103/cm2) and chloroplasts (1.7-4.9 106/cm2). Also low are the values of such integral indexes as relative surface of mesophyll cells (Ames/A, 2.78-5.28) and relative surface of chloroplasts (Achl/A, 1.9-3.2). The leaf mesostructure of wild ginseng shows traits of a plant typically found in shady forest habitats. The photosynthetic apparatus of ginseng adapts to various habitat conditions on the level of leaf mesostructure, through structural transformations of mesophyll tissue, such as changes in the number and size of cells and chloroplasts and also the integral surface indexes Achl/A and Ames/A.

Girdling was applied to 5-year-old potted beech individuals of early, intermediate and late phenological forms to block assimilate export from leaves. Phloem severance caused accumulation of soluble carbohydrates and starch in leaves and increased the C/N ratio. While the hexose content increased continuously until the end of the experiment, the sucrose and starch contents peaked earlier, depending on the plant's phenological features. Different rates of chlorophyll degradation and H2O2 and TBARS (thiobarbituric acid-reactive substances) production in different phenological forms implied that phloem girdling was the source of oxidative stress and, depending on the phenological form, accelerated leaf senescence to different degrees. The variable rate of the increase in soluble carbohydrate and starch content, characteristic of the different phenological forms, had different modifying effects on the antioxidant activity in leaves. Compared with the early phenological form, the late form was characterized by a smaller increase in H2O2 and TBARS content and delayed and slowed chlorophyll and carotenoid degradation. In conjunction with the larger increase in the activity of antioxidant enzymes (catalase, ascorbate peroxidase and superoxide clismutase) induced by carbohydrate accumulation and slower carotenoid degradation, these changes led to the late form having greater resistance to oxidative stress and slower senescence.

This work deals with the effectiveness of a multi-body approach for the study of the dynamic behavior of a fixed landing gear, especially the research project concerns the drop tests of the AP.68 TP-300 aircraft. First, the Digital Mock-up of the of landing gear system in a C.A.D. software has been created, then the experimental structural stiffness of the leaf spring has been validated using the FEM tools MSC.Patran/Nastran. Finally, the entire model has been imported in MSC.ADAMS environment and, according to the certifying regulations, several multi-body simulations have been performed varying the heights of fall and the weights of the system. The results have shown a good correlation between numerical and experimental tests, thus demonstrating the potential of a multi-body approach. Future development of the present activity will probably be an application of the methodology, herein validated, to other cases for a more extensive validation of its predictive power and development of virtual certification procedures.

We examined whether peroxidase activity in cutting bases and leaves and starch content in cutting bases can be used as rooting phase markers in the elepidote rhododendron cv. ‘Babites Baltais’ (Rhododendron L.). Changes in peroxidase activity in cutting leaves and bases, as well as starch content in cutting bases, were determined in relation to anatomical stages of rhizogenesis in leaf bud cuttings treated with 1% indole-3-butyric acid (IBA+) or without IBA (IBA-). The pattern of change of peroxidase activity was similar in cutting bases and leaves of IBA- leaf bud cuttings. Three phases of adventitious root formation were identified: induction, initiation and expression. During the induction phase peroxidase activity decreased, but no anatomical changes were observed in the cuttings. Peroxidase activity increased in the initiation phase when adventitious root initials were formed. Peroxidase activity decreased during the expression phase when adventitious root primordia developed. The starch content of IBA- leaf bud cuttings decreased during the first few days and then gradually rose to maximum, followed by a sharp reduction and another increase at the end of the experiment. The changes of starch content did not coincide with rooting phases as peroxidase activity did, and cannot be used as a rooting phase marker in rhododendrons. Adventitious root formation did not occur in IBA+ leaf bud cuttings, so distinct rooting phases could not be observed. There was a significant correlation between peroxidase activity in cutting bases and leaves of IBA- leaf bud cuttings. Peroxidase activity in leaves of rhododendron leaf bud cuttings are potentially useful as a marker for rooting phases, but that requires further anatomical and physiological study of rooting in leaf bud cuttings.

Septoria melissae Desm., the most important pathogen of lemon balm (Melissa officinalis) occurs each year on plantations. The fungus may cause serious yield losses in the absence of proper plant protection. Breeding resistant or tolerant cultivars could play an important role in plant protection of medicinal plants. However, only a few descriptions of tolerant varieties of lemon balm are available. The goal of this work was to evaluate the susceptibility of three accessions of M. officinalis against the pathogen of Septoria leaf spot under field conditions at Budapest-Soroksár (Hungary) in 2017–2018. Differences in susceptibility of the accessions were observed in both years. The accession of M. officinalis subsp. altissima proved to be the least susceptible to Septoria infection. The frequency of the infected leaves was only 5.1 and 28.1% in 2017 and 2018, respectively. However, the cultivar M. officinalis subsp. officinalis ‘Lorelei’ turned out to be the most susceptible to the pathogen with an average infection level of 26.1 and 66.6%, 1.3–6.1 times higher than that of the other accessions in each year, respectively. Development of disease tolerant M. officinalis cultivars may be an effective tool in the plant protection of lemon balm.

Two field experiments were established at the Agricultural Experimental Station of the National Research Centre at Nubaria, Beheira Governorate, Egypt to study the herbicidal potential of the leaf extract of Eucalyptus citriodora at 5, 10, 15, 20 and 25% compared to two hand hoeing, unweeded treatments and the chemical herbicides Bentazon + Clethodium, Bentazon + Fluazifop-P-butyl and Butralin on pea plants and associated weeds. The results indicated that two hand hoeing achieved the maximum weed depression as expressed by the dry matter of total weeds. The dry matter of total weeds decreased by 95.08 to 94.77% as compared with unweeded treatment 50 and 70 days after sowing (DAS) followed by Butraline (93.93–94.65%), Bentazon + Clethodium (93.26–94.07%), Bentazon + Fluazifop--P-butyl (91.82–92.77%) and leaf extract of Eucalyptus at 25% (91.61–91.95%). Furthermore, the reduction in weed development was accompanied by enhanced pea growth and yield. The results revealed that two hand hoeing was the best treatment to increase plant height, shoot dry weight and SPAD value at 50 and 70 DAS. Also, two hand hoeing produced the maximum values of pod length and number of seeds/pod. The results also indicated that Bentazon + Clethodium treatment gave observable values [recorded 72.96% in pod yield (ton ⋅ fed.–1) over that of unweeded control] of number of pod/plant, weight of pod/plant, seed yield/fed and protein percentage. Also, the results revealed great increases in the growth of pea as well as yield due to treatment with E. citriodora dry leaf extract at 25%. [recorded 64.8% in in pod yield (ton ⋅ fed.–1) over that of unweeded control]. So, the results indicated using Bentazon + Clethodium as well as E. citriodora dry leaf extract at 25% to control weeds associated with pea plants. The authors suggested application of E. citriodora dry leaf extract at 25% in controlling weeds associated with pea plants as a safe method that avoids environmental contamination.