scholarly journals Evaluation of Natural and Factitious Food Sources for Pronematus Ubiquitus on Tomato Plants

Author(s):  
Marcus V. A. Duarte ◽  
Dominiek Vangansbeke ◽  
Juliette Pijnakker ◽  
Rob Moerkens ◽  
Alfredo Benavente ◽  
...  

Pronematus ubiquitus (McGregor) is a small iolinid mite that is capable of establishing on tomato plants. Once established, this mite has been shown to control both tomato russet mite, Aculops lycopersici (Tryon) (Acari: Eriophyidae) and tomato powdery mildew (Oidium neolycopersici L. Kiss). In the present study, we explored the nutritional value of various food sources in the laboratory. First, we assessed the reproduction of two food sources that P. ubiquitus can encounter on a tomato crop: tomato pollen and powdery mildew. In a second laboratory experiment, we evaluated the nutritional value of two types of prey mites: the astigmatid Carpoglyphus lactis L. (Acari: Carpoglyphidae) and the tarsonemid Tarsonemus fusarii (Acari: Tarsonemidae). Powdery mildew and C. lactis did not contribute to the reproduction, whereas tomato pollen and T. fusarii did allow egg-laying. However, Typha angustifolia pollen was a superior food source in both experiments. In a greenhouse trial on individual caged tomato plants, we evaluated the impact of pollen supplementation frequency on establishment of P. ubiquitus. Here, a pollen addition frequency of every other week was required to allow populations of P. ubiquitus to establish.

Insects ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1111
Author(s):  
Marcus V. A. Duarte ◽  
Dominiek Vangansbeke ◽  
Juliette Pijnakker ◽  
Rob Moerkens ◽  
Alfredo Benavente ◽  
...  

Pronematus ubiquitus (McGregor) is a small iolinid mite that is capable of establishing on tomato plants. Once established, this mite has been shown to control both tomato russet mite, Aculops lycopersici (Tryon) (Acari: Eriophyidae), and tomato powdery mildew (Oidium neolycopersici L. Kiss). In the present study, we explored the effects of a number of alternative food sources on the oviposition rate in the laboratory. First, we assessed the reproduction on food sources that P. ubiquitus can encounter on a tomato crop: tomato pollen and powdery mildew, along with tomato leaf and Typha angustifolia L. In a second laboratory experiment, we evaluated the oviposition rate on two prey mites: the astigmatid Carpoglyphus lactis L. (Acari: Carpoglyphidae) and the tarsonemid Tarsonemus fusarii Cooreman (Acari: Tarsonemidae). Powdery mildew and C. lactis did not support reproduction, whereas tomato pollen and T. fusarii did promote egg laying. However, T. angustifolia pollen resulted in a higher oviposition in both experiments. In a greenhouse trial on individual caged tomato plants, we evaluated the impact of pollen supplementation frequency on the establishment of P. ubiquitus. Here, a pollen addition frequency of every other week was required to allow populations of P. ubiquitus to establish.


2006 ◽  
Vol 96 (9) ◽  
pp. 967-974 ◽  
Author(s):  
Yoshinori Matsuda ◽  
Hiroki Ikeda ◽  
Nobuyuki Moriura ◽  
Norio Tanaka ◽  
Kunihiko Shimizu ◽  
...  

In an attempt to physically protect greenhouse tomato plants from the powdery mildew fungus Oidium neolycopersici, we developed a new electrostatic spore precipitator in which a copper wire conductor is linked to an electrostatic generator and covered with a transparent acrylic cylinder (insulator). The conductor was negatively charged by the generator, and the electrostatic field created by the conductor was used to dielectrically polarize the insulator cylinder. The dielectrically polarized cylinder also produced an electrostatic force without a spark discharge. This force was directly proportional to the potential applied to the conductor and was used to attract conidia of the pathogen. The efficacy of this spore precipitator in protecting hydroponically cultured tomato plants from powdery mildew was evaluated in the greenhouse. The hydroponic culture troughs were covered with a cubic frame installed with the spore precipitator, and the disease progress on precipitator-guarded and unguarded seedlings was traced after the conidia were disseminated mechanically from inoculum on tomato plants. Seedlings in the guarded troughs remained uninfected during the entire experiment, in spite of rapid spread of the disease to all leaves of the unguarded seedlings.


Author(s):  
Sattarov Abdumurod Sattarovich ◽  

This article analyzes the synthesis of the Tenebrio molitor protein (Coleoptera: Tenebrionidae) belonging to a food insect, depending on its nutrient content. Differences in protein synthesis by Tenebrio molitor larvae were shown when wheat bran and flour from the macrophytesLemna minor and Azollacarolina were added. In particular, it was noted that TMO-2 and TMO-6 T.molitor F6 larvae are synthesized on average 31.02% protein in wheat bran, 38.13% in duckweed and 30.87% in azole. It was found that the larvae of variant F6 grown on wheat bran synthesized protein on average 4.79% less than the variant F1 of wheat. F6 larvae grown in duckweed synthesized 7.11% more protein than larvae grown in wheat bran and 0.15% less protein synthesis than larvae grown in azole. It was found that F6 larvae grown in duckweed produce 7.26% more protein than larvae grown in azole. Summarizing these indicators, it was noted that in the body of larvae eating macrophytes insufficient absorption of nutrients, low moisture content in the feed led to their death, egg laying and larvae of variant F6 produced significantly less protein than variant F1. When feeding macrophytes, it is advisable to takeintoaccountits moisture content or add flour based on them to other food sources. It was studied that egg-laying larvae grown on the basis of azole accounted for 38.14%, whereas in duckweed this indicator was 58.38%. It was found that in larvae grown on wheat bran, the percentage of egg-laying is 68.85%. The mortality rate of larvae feeding on wheat bran was 18.22%, in duckweed - 44.63%, in azole - 62.27%, this is due to insufficient moisture in the composition of duckweed and azole (average humidity 3.4-4.2%), relatively high humidity (average humidity 9.58-10.12%) in wheat bran. Survival coefficients of Tenebrio molitor F6 larvae were determined in three different compositions and sources of nutrients with different humidity (wheat bran, Lemna minor and flour Azollacarolina). Tenebrio molitor F6 larvae of the generation of variants TMO-2 and TMO-6 were grown on wheat bran with an average survival rate of 0.79, on duckweed flour - 0.50, on azolla flour - 0.64. It was noted that the survival rate of larvae grown on wheat bran was 15.5% higher than that of larvae grown on azolla, and it is advisable to explain the source not by the protein reserve, but by the amount of moisture in it. It was noted that the moisture content (9.58-10.12%) (protein 15%) in wheat bran was a factor in the high viability of the larvae compared to azolla (protein-27%, humidity 8.2%). Despite the easy protein synthesis in the body of larvae in duckweed flour (protein - 16.1%, humidity - 4.4%) compared to azolla flour, its content is 3.8% lower than that of azolla, due to the fact that survival the larvae in them were lower than in wheat and azolla. Therefore, along with the protein content, moisture is an important factor when choosing a food source. When summing the survival rates of larvae of the Tenebrio molitor F6 generation in the studied nutrient media, the average survival was calculated as 0.96. This means that based on the established ratios of wheat bran, duckweed and azolla flour, it will be possible to create a nutrient medium with a new content, high nutritional value and low cost


Plant Disease ◽  
2015 ◽  
Vol 99 (2) ◽  
pp. 288-288 ◽  
Author(s):  
X.-M. Liu ◽  
Y.-X. Wei ◽  
H. Zhang ◽  
F.-X. Zhou ◽  
J.-J. Pu

Croton (Codiaeum variegatum (Linn.) var. pictum (Lodd.)) is an ornamental plant commonly grown in southern China. In March 2014, severe powdery mildew infections were observed on crotons in gardens of Hainan University (20.1°N and 110.3°E), Haikou, Hainan province. Disease incidence was estimated in a random batch of 100 plants in three replicates, with the average value approaching 80%. Symptoms first appeared as white circular patches on the adaxial surface and expanded to the abaxial surface, petioles, and stems. The top leaves were the most affected. Upper surfaces of the infected leaves were covered by white, dense mycelia. As the disease progressed, infected leaves turned purple on the lower surfaces and curly before becoming necrotic and abscising from the plant. Powdery mildew was more severe in shaded environments, especially during rainy or foggy weather in early spring. Two hundred conidiophores and conidia were observed microscopically. The conidiophores were straight or occasionally flexuous, 62.3 to 127.6 × 6.2 to 10.2 μm, consisting of two to three straight cells. Conidia were born in solitary on the top of conidiophores. Conidia were hyaline, ellipsoidal, 26.4 to 42.2 × 11.7 to 23.4 μm (average 32.5 × 16.5 μm), contained no distinct fibrosin bodies, and produced a subterminal germ tube. The wrinkling pattern of the outer walls of older conidia was angular or reticulated. Appressoria were single and multilobed. Cleistothecia were not observed. Based on morphological characteristics, the fungus was identified as Oidium neolycopersici (2), which was recently renamed Pseudoidium neolycopersici (L. Kiss) (3). The identity was confirmed by sequence analysis. Genomic DNA was extracted from the foliar powdery mildew colonies using Chelex-100 (Bio-Rad, Shanghai, China). The rDNA internal transcribed spacer (ITS) region was amplified with primers ITS1 and ITS4 (5). The ITS sequence of the representative isolates C01 (GenBank Accession No. KJ890378.1) and four other powdery mildew samples collected from crotons in Hainan University was 100% identical to that of P. neolycopersici isolates from tomato plants such as JQ972700 and AB163927. Inoculations were made by gently pressing diseased leaves onto leaves of five healthy plants of croton and tomato (‘Money maker’). Five non-inoculated croton and tomato plants served as controls. Inoculated and non-inoculated plants were maintained in an incubator at 25°C with a 12-h photoperiod. After eight days, typical powdery mildew symptoms developed on 93% of the inoculated plants, while no symptom developed on the non-inoculated plants. The pathogenicity tests were repeated three times. The same fungus was always re-isolated from the diseased tissue according to Koch's postulates. The pathogenicity tests further confirmed that the pathogen from crotons is P. neolycopersici (Basionym. Oidium neolycopersici (KJ890378.1)), which is commonly known as the tomato powdery mildew. P. neolycopersici is also a pathogen of Normania triphylla (1) and papaya (4). To our knowledge, this is the first report of P. neolycopersici infecting croton. The avenue of this pathogen entering gardens of Hainan University remains unknown. The gardens are located far away from tomato farms. Also no symptom of powdery mildew on croton was observed during surveys in other locations in Haikou. The origin of the pathogen warrants additional research. References: (1) D. Delmail et al. Mycotaxon 113:269, 2010. (2) L. Kiss et al. Mycol. Res. 105:684, 2001. (3) L. Kiss et al. Mycol. Res. 115:612, 2011. (4) J. G. Tsay et al. Plant Dis. 95:1188, 2011. (5) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. Academic Press, San Diego, CA, 1990.


Plant Disease ◽  
2012 ◽  
Vol 96 (6) ◽  
pp. 912-912 ◽  
Author(s):  
M. Stevanović ◽  
I. Stanković ◽  
A. Vučurović ◽  
N. Dolovac ◽  
E. Pfaf-Dolovac ◽  
...  

In September 2011, tomato (Solanum lycopersicum L. ‘Big Beef’) plants showing typical symptoms of powdery mildew were collected in a greenhouse in the vicinity of Padinska Skela (District of City of Belgrade) in Serbia. Numerous circular, white colonies of powdery mildew were observed predominantly on the adaxial surface of the leaves, the petioles, and the stems. The foliage of infected plants turned yellow and necrotic, which was followed by rapid defoliation. Disease incidence was estimated by counting plants with powdery mildew symptoms in a random batch of 100 plants in four replicates and estimated to be extremely high, approaching 90%. Tomato plants (‘Novosadski Jabučar’) were inoculated with conidia released from diseased tomato leaves positioned above the tomato leaves and maintained at 25°C with a 14-h photoperiod. Healthy tomato plants from the same lot, which were not exposed to the conidia shower, were used as negative control. The first white fungal colonies appeared on the leaves of the inoculated plants within 4 to 7 days after inoculation, while no fungal growth was observed in the control plants. To determine the morphological characteristics of the pathogen, surface mycelium was removed with small strips of clear adhesive tape and examined using light microscopy. Microscopic observation revealed mycelium with lobed appressoria and hyaline, ellipsoid-ovoid or doliform conidia (32.5 to 47.5 × 17.5 to 25 μm) with no distinct firosin bodies and which produced sub-terminal germ tubes. Conidia were produced on the unbranched, erect conidiophores (82.5 to 150 μm) consisting of a cylindrical foot-cell followed by one to three short cells. No chasmothecia were found. On the basis of morphological characteristics, the pathogen was identified as Oidium neolycopersici (4), which was confirmed by internal transcribed spacer (ITS) sequence analysis. Total DNA was extracted directly from the whitish spots of superficial mycelium on the leaves with a DNeasy Plant Mini Kit (Qiagen, Hilden, Germany) following the manufacturer's instructions. PCR amplification and sequencing were performed with primers ITS1F and ITS4 (1). The nucleotide sequence of the representative isolate 809-11 (Accession No. JQ619840) shared 100% identity with 16 O. neolycopersici isolates deposited in GenBank from different parts of the world. Tomato powdery mildew caused by O. neolycopersici is present in many European (4) and other countries around the world (3) and is becoming economically very important as majority of the tomato cultivars have shown to be susceptible (2). To our knowledge, this is the first report of O. neolycopersici in Serbia. Because tomato is a very popular and widely grown vegetable in Serbia, the presence of a new and potentially harmful disease could endanger greenhouse as well as open field tomato production. References: (1) J. H. Cunnington et al. Australas. Plant Pathol. 32:421, 2003. (2) T. Jankovics et al. Phytopathology 98:529, 2008. (3) H. Jones et al. Mol. Plant Pathol. 2:303, 2001. (4) L. Kiss et al. Mycol. Res. 105:684, 2001.


2018 ◽  
Vol 69 (4) ◽  
pp. 961-964
Author(s):  
Andrei Vasile Olteanu ◽  
Georgiana Emmanuela Gilca Blanariu ◽  
Gheorghe Gh. Balan ◽  
Dana Elena Mitrica ◽  
Elena Gologan ◽  
...  

Non-alcoholic fatty liver disease (NAFLD) has become of major interest worldwide, it is estimated that more than 20% of the general population suffer from liver steatosis. NAFLD is highly associated with metabolic risk factors like type 2 diabetes mellitus, obesity and dyslipidemia, the patients diagnosed with NAFLD should adopt a high fiber low calorie diet, with reduced saturated fat and carbohydrates content, leading to weight loss and improvement of metabolic profile. Our study is aiming to shape the profile of the patient interested in being informed related to food quality and chemical composition and to evaluate the aspects on the food products label which are important for the customer. Between June 2017 and December 2017, 83 patients diagnosed with NASH were included in the study, representing the study group, while 33 subjects, without metabolic syndrome or digestive diseases, selected from patient list belonging to two general practitioners, constituted the control group. Related to the interest of being informed about the chemical composition and nutritional value of the products bought, the study showed a low interest for the provided information on nutritional value. lack of confidence in the provided information and complexity of the information are understandable, the high number of subject reasoning through lack of immediate clinical benefit is surprising. Among the healthy population the willingness to pay attention to this aspect is extremely low.


Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1639
Author(s):  
Emma Neylon ◽  
Elke K. Arendt ◽  
Emanuele Zannini ◽  
Aylin W. Sahin

Recycling of by-products from the food industry has become a central part of research to help create a more sustainable future. Brewers’ spent grain is one of the main side-streams of the brewing industry, rich in protein and fibre. Its inclusion in bread, however, has been challenging and requires additional processing. Fermentation represents a promising tool to elevate ingredient functionality and improve bread quality. Wheat bread was fortified with spray-dried brewers’ spent grain (BSG) and fermented brewers’ spent grain (FBSG) at two addition levels to achieve “source of fibre” and “high in fibre” claims according to EU regulations. The impact of BSG and FBSG on bread dough, final bread quality and nutritional value was investigated and compared to baker’s flour (BF) and wholemeal flour (WMF) breads. The inclusion of BSG and FBSG resulted in a stronger and faster gluten development; reduced starch pasting capacity; and increased dough resistance/stiffness. However, fermentation improved bread characteristics resulting in increased specific volume, reduced crumb hardness and restricted microbial growth rate over time. Additionally, the inclusion of FBSG slowed the release in reducing sugars over time during in vitro starch digestion. Thus, fermentation of BSG can ameliorate bread techno-functional properties and improve nutritional quality of breads.


Plant Disease ◽  
2006 ◽  
Vol 90 (7) ◽  
pp. 915-919 ◽  
Author(s):  
W. Oichi ◽  
Y. Matsuda ◽  
T. Nonomura ◽  
H. Toyoda ◽  
L. Xu ◽  
...  

The formation of conidial pseudochains by the tomato powdery mildew Oidium neolycopersici on tomato leaves was monitored using a high-fidelity digital microscope. Individual living conidiophores that formed mature conidial cells at their apex were selected for observation. The conidial cells were produced during repeated division and elongation by the generative cells of the conidiophores. Under weak wind conditions (0.1 m/s), these conidial cells did not separate from each other to produce a chain of conidial cells (pseudochain). The pseudochains dropped from the conidiophores once four conidial cells were connected. The conidiophores resumed conidium production, followed by another cycle of pseudochain formation. The formation of pseudochains by tomato powdery mildew was not influenced by the ambient relative humidity. On the other hand, the conidial cells produced were easily wind dispersed without forming pseudochains when conidiophores were exposed to stronger winds (1.0 m/s). The present study successfully demonstrated that the pathogen required wind to disperse progeny conidia from the conidiophores and produced conidial pseudochains when the wind was below a critical level, independent of high relative humidity as reported previously.


2014 ◽  
Vol 112 (8) ◽  
pp. 1373-1383 ◽  
Author(s):  
Susan I. Barr ◽  
Loretta DiFrancesco ◽  
Victor L. Fulgoni

Although breakfast is associated with more favourable nutrient intake profiles in children, limited data exist on the impact of breakfast on nutrient adequacy and the potential risk of excessive intakes. Accordingly, we assessed differences in nutrient intake and adequacy among breakfast non-consumers, consumers of breakfasts with ready-to-eat cereal (RTEC) and consumers of other types of breakfasts. We used cross-sectional data from 12 281 children and adolescents aged 4–18 years who took part in the nationally representative Canadian Community Health Survey, 2004. Mean nutrient intakes (obtained using a multiple-pass 24 h recall method) were compared among the breakfast groups using covariate-adjusted regression analysis. Usual nutrient intake distributions, generated using the National Cancer Institute method, were used to determine the prevalence of nutrient inadequacy or the potential risk of excessive intakes from food sources alone and from the combination of food plus supplements. Of these Canadian children, 10 % were breakfast non-consumers, 33 % were consumers of RTEC breakfasts and 57 % were consumers of other types of breakfasts. Non-consumption of breakfast increased with age (4–8 years: 2 %; 9–13 years: 9 %; 14–18 years: 18 %). Breakfast consumers had higher covariate-adjusted intakes of energy, many nutrients and fibre, and lower fat intakes. The prevalence of nutrient inadequacy for vitamin D, Ca, Fe and Mg (from food alone or from the combination of food plus supplements) was highest in breakfast non-consumers, intermediate in consumers of other types of breakfasts and lowest in consumers of RTEC breakfast. For vitamin A, P and Zn, breakfast non-consumers had a higher prevalence of nutrient inadequacy than both breakfast groups. The potential risk of excessive nutrient intakes was low in all groups. Efforts to encourage and maintain breakfast consumption in children and adolescents are warranted.


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