81. |
82. Record of a new location for tropical root knot nematode Meloidogyne luci in SloveniaBarbara Gerič Stare, Polona Strajnar, Saša Širca, Nik Susič, Gregor Urek, original scientific article Abstract: The plant parasitic nematode Meloidogyne ethiopica Whitehead has been reported from several European countries, including Slovenia, where it was first found in 2003. However, the description in 2014 of a new sister species, Meloidogyne luci Carneiro et al., 2014, called for the reclassification of all European and Turkish populations of M. ethiopica reported up to this date as M. luci. Both species M. ethiopica and M. luci have a very wide host range of
monocotyledons and dicotyledons. They are pests of important agricultural crops such as maize, potatoes and variety of vegetables, and represent a serious threat for agricultural production in greenhouses as well as in the open fields in many EPPO countries. This paper reports a new location of the tropical root knot nematode species M. luci found in Slovenia in 2015.
Keywords: parasitic nematode, root knot nematode, classification, populations
Published in DiRROS: 20.07.2018; Views: 2773; Downloads: 1209
 Full text (111,85 KB) |
83. Discrimination between abiotic and biotic drought stress in tomatoes using hyperspectral imagingNik Susič, Uroš Žibrat, Saša Širca, Polona Strajnar, Jaka Razinger, Matej Knapič, Andrej Vončina, Gregor Urek, Barbara Gerič Stare, original scientific article Abstract: Crop plants are subjected to various biotic and abiotic stresses. Both root-knot nematodes (biotic stress) and water deficiency (abiotic stress) lead to similar drought symptoms in the plant canopy. In this work, hyperspectral imaging was used for early detection of nematode infestation and water deficiency (drought) stress in tomato plants. Hyperspectral data in the range from 400 to 2500 nm of plants subjected to different watering regimes and nematode infestation levels were analysed by partial least squares – discriminant analysis (PLS-DA) and partial least squares – support vector machine (PLS-SVM) classification. PLS-SVM classification achieved up to 100% accuracy differentiating between well-watered and water-deficient plants, and between 90 and 100% when identifying nematode-infested plants. Grouping the data according to the time of imaging increased the accuracy of classification. Shortwave infrared spectral regions associated with the OH and CH stretches were most relevant for the identification of nematode infested plants and severity of infestation. This study demonstrates the capability of hyperspectral imaging to identify and discriminate between biotic and abiotic plant stresses.
Keywords: nematode, Hyperspectral imaging, Drought stress, Root-knot nematode, Tomato
Published in DiRROS: 20.07.2018; Views: 3861; Downloads: 2382
Full text (847,87 KB)
This document has many files! More... |
84. |
85. Stable carbon isotopes in Norwey spruce (Picea abies (L.) Karst.) tree rings at two sites in SloveniaPolona Hafner, Tom Levanič, 2009, original scientific article Abstract: Stable isotopes in tree rings are an important tool in climate reconstruction and in studies of tree response on environmental factors in the past, similar like maximum latewood density, tree ring width and other tree ring parameters.In this article we present stable carbon isotopes physiology and the first two Slovenian d13C chronologies for Norway spruce (Picea abies (L.) Karst.) growing at two sites with different ecological conditions. Five trees were sampled at Pokljuka alpine site and three at Sorško polje lowland plantation. d13C values were compared with CRU TS 1.2 meteorological data-set,which provides information on climate in Europe for the 1901-2000 period at a 10ć spatial resolution. Results of correlation analysis for both sites revealed similar average d13C values, which are in strong negative correlation with amount of precipitation and positive correlation with temperatures in the growing period. Temporal stability of the correlation between precipitation and d13C values in July is significant for both sites, where as the stability of d13C - temperature relationship is significant only for the Sorško polje site.
Published in DiRROS: 12.07.2017; Views: 4169; Downloads: 1925
Full text (1,07 MB) |
86. Vpliv klime na maksimalno gostoto kasnega lesa v branikah smreke (Picea abies (L.) Karst.) na dveh rastiščih v SlovenijiPolona Hafner, Tom Levanič, 2008, original scientific article Abstract: Navadna smreka (Picea abies (L.) Karst.) je zaradi svoje razširjenosti, zgradbe lesa in dolge življenjske dobe razmeroma pogost objekt dendrokronoloških raziskav. Doslej objavljene slovenske smrekove kronologije so bile sestavljene na podlagi širin branik, prispevek pa predstavlja prve denzitokronologije v Sloveniji in opisuje metodo določanja maksimalne gostote kasnega lesa branike (MXD). Raziskava je potekala na dveh različnih smrekovih rastiščih - Pokljuki in Sorškem polju. Na obeh lokacijah smo v vzorec zajeli po 13 dreves. Rezultati, dobljeni na Sorškem polju, so pokazali višje vrednosti MXD in manjše število značilnih let. Analiza je pokazala tudi pozitivno korelacijo med MXD in temperaturami v avgustu in septembru.
Keywords: smreka, Picea abies, klima, gostota lesa, kasni les, denzitometrija
Published in DiRROS: 12.07.2017; Views: 4746; Downloads: 1990
Full text (1,10 MB) |
87. Annual cambial rhythm in Pinus halepensis and Pinus sylvestris as indicator for climate adaptationPeter Prislan, Jožica Gričar, Martin De Luis, Klemen Novak, Edurne Martinez Del Castillo, Uwe Schmitt, Gerald Koch, Jasna Štrus, Polona Mrak, Magda Tušek-Žnidarič, Katarina Čufar, 2016, original scientific article Abstract: To understand better the adaptation strategies of intra-annual radial growth in Pinus halepensis and Pinus sylvestris to local environmental conditions, we examined the seasonal rhythm of cambial activity and cell differentiation at tissue and cellular levels. Two contrasting sites differing in temperature and amount of precipitation were selected for each species, one typical for their growth and the other represented border climatic conditions, where the two species coexisted. Mature P. halepensis trees from Mediterranean (Spain) and sub-Mediterranean (Slovenia) sites, and P. sylvestris from sub-Mediterranean (Slovenia) and temperate (Slovenia) sites were selected. Repeated sampling was performed throughout the year and samples were prepared for examination with light and transmission electron microscopes. We hypothesized that cambial rhythm in trees growing at the sub-Mediterranean site where the two species co-exist will be similar as at typical sites for their growth. Cambium in P. halepensis at the Mediterranean site was active throughout the year and was never truly dormant, whereas at the sub-Mediterranean site it appeared to be dormant during the winter months. In contrast, cambium in P. sylvestris was clearly dormant at both sub-Mediterranean and temperate sites, although the dormant period seemed to be significantly longer at the temperate site. Thus, the hypothesis was only partly confirmed. Different cambial and cell differentiation rhythms of the two species at the site where both species co-exist and typical sites for their growth indicate their high but different adaptation strategies in terms of adjustment of radial growth to environmental heterogeneity, crucial for long-term tree performance and survival.
Keywords: Aleppo pine, Pinus halepensis, Scots pine, Pinus sylvestris, cambium, light microscopy, Mediterranean environment, temporate environment, transmission electron microscopy, xylem
Published in DiRROS: 12.07.2017; Views: 3128; Downloads: 1425
Full text (4,63 MB)
This document has many files! More... |
88. |
89. Proučevanje gozdnih tal na stalnih raziskovalnih ploskvahJanko Kalan, Polona Kalan, Primož Simončič, 1995, original scientific article Abstract: V Sloveniji postavljamo sistem raziskovalnih ploskev za trajno opazovanje gozdnih ekosistemov. Opisana so merila za izbiro ploskev, na katerih proučujemo gozdna tla. Navedeni so tudi napotki za terenske in laboratorijske preiskave tal ter prikaz analiznih rezultatov.
Keywords: tla, gozd, raziskovalna ploskev, raziskava, metoda dela, Slovenija
Published in DiRROS: 12.07.2017; Views: 4293; Downloads: 1829
Full text (1,02 MB) |
90. Bioindikacija onesnaženosti gozdov z žveplom na podlagi vsebnosti žvepla v asimilacijskih delih gozdnega drevjaJanko Kalan, Polona Kalan, Primož Simončič, 1995, original scientific article Abstract: Po izkušnjah raziskav, ki so bile izvedene v letih 1985-1993 na točkah osnovne bioindikacijske mreže (16x16 km), sklepamo, da je bioindikacija onesnaženosti zraka z žveplovim dioksidom po metodi analize vsebnosti žvepla v iglicah smreke, črnega in rdečega bora zelo primerna in tudi dovolj zanesljiva za ugotavljanje ogroženosti gozdov zaradi žveplovega dioksida. Gozdovi na območju Alp, Trnovskega gozda, Snežnika, Javornika, širšega kočevsko-ribniškega območja in Gorjancev so najmanj obremenjeni z žveplom. Najbolj obremenjeni gozdovi pa so na območju Koroške, Celja, Ljubljane, Zasavja, Maribora in Prekmurja. Vsebnost žvepla se je v zadnjih letih povečala na območjih ob meji z Italijo, Hrvaško in Madžarsko ter v bližini močnih emijsiskih virov v notranjosti Slovenije.
Keywords: bioindikacija, analiza, iglice, žveplo, ovrednotenje, Slovenija
Published in DiRROS: 12.07.2017; Views: 4197; Downloads: 1831
Full text (1,29 MB) |
