Supplementary data for the article: Pavlovic, J.; Samardzic, J.; Kostic, L.; Laursen, K. H.; Natic, M.; Timotijevic, G.; Schjoerring, J. K.; Nikolic, M. Silicon Enhances Leaf Remobilization of Iron in Cucumber under Limited Iron Conditions. Annals of Botany 2016, 118 (2), 271–280. https://doi.org/10.1093/aob/mcw105

Supplementary material for: [https://doi.org/10.1093/aob/mcw105]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2305

Silicon enhances leaf remobilization of iron in cucumber under limited iron conditions

Background and Aims Retranslocation of iron (Fe) from source tissues enhances plant tolerance to Fe deficiency. Previous work has shown that silicon (Si) can alleviate Fe deficiency by enhancing acquisition and root to shoot translocation of Fe. Here the role of Si in Fe mobilization in older leaves and the subsequent retranslocation of Fe to young leaves of cucumber (Cucumis sativus) plants growing under Fe-limiting conditions was investigated. Methods Iron (Fe-57 or naturally occurring isotopes) was measured in leaves at different positions on plants hydroponically growing with or without Si supply. In parallel, the concentration of the Fe chelator nicotianamine (NA) along with the expression of nicotianamine synthase (NAS) involved in its biosynthesis and the expression of yellow stripe-like (YSL) transcripts mediating Fe-NA transport were also determined. Key Results In plants not receiving Si, approximately half of the total Fe content remained in the oldest leaf. In contrast, Si-treated plants showed an almost even Fe distribution among leaves with four different developmental stages, thus providing evidence of enhanced Fe remobilization from source leaves. This Si-stimulated Fe export was paralleled by an increased NA accumulation and expression of the YSL1 transporter for phloem loading/unloading of the Fe-NA complex. Conclusions The results suggest that Si enhances remobilization of Fe from older to younger leaves by a more efficient NA-mediated Fe transport via the phloem. In addition, from this and previous work, a model is proposed of how Si acts to improve Fe homeostasis under Fe deficiency in cucumber

THE FIRST CASE OF OCULAR THELAZIASIS IN CROATIA

Prikazujemo slučaj okularne infekcije uzrokovane telazijom u 82-godišnjeg bolesnika. Infekcija pripada skupini zoonoza, a uzrokovana je parazitom (nematodom) iz porodice Thelaziide. Opisane su dvije vrste telazija koje uzrokuju infekciju u ljudi: Thelazia callipaeda i Thelazija californiensis. Prenosi se sa životinja, najčešće psa, na čovjeka putem muha iz porodice Drosophilidae. Bolesnik se javlja u hitnu oftalmološku ambulantu zbog bolova i svrbeža u lijevom oku koji traju već nekoliko dana. Prigodom prvog pregleda ustanovljeno je jako crvenilo konjunktive i cilijarnog područja, te veliki kornealni apsces pozitivan na fl uorescenski test bez vidljivih struktura u pozadini. Pregledom vanjskog konjunktivalnog kuta, pod vjeđom, uoči se pokretna, crvolika forma. Tijekom pregleda, uz lokalnu anesteziju tetrakainom, ukupno je odstranjeno sedam sitnih, mliječno bijelih crva različitih veličina i faze razvoja. Nakon kirurške ekstirpacije parazita, učini se mikrobiološka identifi kacija i utvrdi dijagnoza telazioze.The fi rst case of ocular thelaziasis in a human male patient in Croatia is presented. Thelaziasis is a zoonosis caused by nematodes of the genus Thelazia, parasites of the conjunctival bags or tear ducts of mammals and birds. Two types of the genus Thelazia (T.) have been described as causes of infection in humans, T. callipaeda and T. californiensis. To date, less than 300 thelaziasis cases in humans have been reported. This zoonosis is very rare in humans in European countries, with a high incidence in Asian countries, especially in China, Thailand and Japan. Because of the high prevalence of the parasites in the Far East, T. callipaeda is called ‘Oriental eye worm’. The fi rst case of thelaziasis in Europe was described in 2008 in Italy and France, where cases in animals had already been reported. Seasonal occurrence of thelaziasis in Europe depends on the presence of the vector, fruit fl ies of Drosophilidae family, Phortica variegate as the most common type. Adult worm is milky white, females grow to 20 mm and males up to 12 mm. Dogs and cats are the most common sources of infection for humans, which occurs as unilateral ocular infection. The clinical picture of infection is similar to bacterial and allergic conjunctivitis with tearing and foreign body sensation. After removal of worms, clinical signs quickly disappear and there is no need for anthelmintic treatment. In the treatment of secondary infections, local antibiotics and corticosteroids can be applied. The 82-year-old male patient presented to outpatient ophthalmology clinic for occasional sensation of pain, itching, redness and tearing in his left eye during the last few days. His left eye was blind due to previous retinal detachment and had severe conjunctival and ciliary infection with large corneal abscess. Worm-like movement in the lateral canthus was observed. After topical anesthesia, seven worms were removed. Upon surgical extirpation of the parasite, the diagnosis of thelaziasis was verifi ed by microbiological identifi cation. Only two cases of Thelazia in dogs were reported in Croatia, in December 2013 and January 2014. It is important to bear in mind this cause of eye infections, especially when caused by larval stages that are diffi cult to identify. Untimely diagnosis and inadequate treatment lead to extended illness and complications. The appearance of this parasite in Croatian patients suggests the need for inclusion of the pathogen in the differential diagnosis of bacterial or allergic conjunctivitis

Supplementary data for the article: Pavlovic, J.; Samardzic, J.; Kostic, L.; Laursen, K. H.; Natic, M.; Timotijevic, G.; Schjoerring, J. K.; Nikolic, M. Silicon Enhances Leaf Remobilization of Iron in Cucumber under Limited Iron Conditions. Annals of Botany 2016, 118 (2), 271–280. https://doi.org/10.1093/aob/mcw105

Supplementary material for: [https://doi.org/10.1093/aob/mcw105]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2305

Silicon enhances leaf remobilization of iron in cucumber under limited iron conditions

Background and Aims Retranslocation of iron (Fe) from source tissues enhances plant tolerance to Fe deficiency. Previous work has shown that silicon (Si) can alleviate Fe deficiency by enhancing acquisition and root to shoot translocation of Fe. Here the role of Si in Fe mobilization in older leaves and the subsequent retranslocation of Fe to young leaves of cucumber (Cucumis sativus) plants growing under Fe-limiting conditions was investigated. Methods Iron (Fe-57 or naturally occurring isotopes) was measured in leaves at different positions on plants hydroponically growing with or without Si supply. In parallel, the concentration of the Fe chelator nicotianamine (NA) along with the expression of nicotianamine synthase (NAS) involved in its biosynthesis and the expression of yellow stripe-like (YSL) transcripts mediating Fe-NA transport were also determined. Key Results In plants not receiving Si, approximately half of the total Fe content remained in the oldest leaf. In contrast, Si-treated plants showed an almost even Fe distribution among leaves with four different developmental stages, thus providing evidence of enhanced Fe remobilization from source leaves. This Si-stimulated Fe export was paralleled by an increased NA accumulation and expression of the YSL1 transporter for phloem loading/unloading of the Fe-NA complex. Conclusions The results suggest that Si enhances remobilization of Fe from older to younger leaves by a more efficient NA-mediated Fe transport via the phloem. In addition, from this and previous work, a model is proposed of how Si acts to improve Fe homeostasis under Fe deficiency in cucumber.Free full text: [https://doi.org/10.1093/aob/mcw105]Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/3608

Silicon alleviates iron deficiency in cucumber by promoting mobilization of iron in the root apoplast

Root responses to lack of iron (Fe) have mainly been studied in nutrient solution experiments devoid of silicon (Si). Here we investigated how Si ameliorates Fe deficiency in cucumber (Cucumis sativus) with focus on the storage and utilization of Fe in the root apoplast. A combined approach was performed including analyses of apoplastic Fe, reduction-based Fe acquisition and Fe-mobilizing compounds in roots along with the expression of related genes. Si-treated plants accumulated higher concentrations of root apoplastic Fe, which rapidly decreased when Fe was withheld from the nutrient solution. Under Fe-deficient conditions, Si also increased the accumulation of Fe-mobilizing compounds in roots. Si supply stimulated root activity of Fe acquisition at the early stage of Fe deficiency stress through regulation of gene expression levels of proteins involved in Fe acquisition. However, when the period of Fe deprivation was extended, these reactions further decreased as a consequence of Si-induced enhancement of the Fe status of the plants. This work provides new evidence for the beneficial role of Si in plant nutrition and clearly indicates that Si-mediated alleviation of Fe deficiency includes an increase of the apoplastic Fe pool in roots and an enhancement of Fe acquisition