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Comparison of seed longevity for thirty forest, grassland and weed species of the Central European flora: results of a seed burial experiment

100%

Csontos P. , Kalapos T. , Tomas J.

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tom 64

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nr 3

EN

We compared seed longevity of herbaceous species in three habitat types differing in stability. We hypothesized that seed longevity is the lowest for forest species (living in stable habitat), the highest for weeds, while species of xerothermic grasslands take an intermediate value. Ten species were selected from each of the three habitats with balanced representation of plant families among habitats. Seeds of the 30 species were deep buried at 65 cm depth, then replicates recovered after 1, 2, 3, 4 and 6 years, and germinated in an unheated greenhouse. Weeds expressed the highest germination rate (36.1% in average) exceeding forest (14.4%) and grassland species (10.2%) which did not differ significantly. The number of species with transient, short-term persistent and long-term persistent seed bank, respectively, was 1, 7 and 2 for grasslands; 1, 3 and 6 for forests; and 0, 1 and 9 for weeds. As expected, weeds possessed the highest seed longevity. Contrary to our assumption, low seed longevity was not the norm among forest understorey species, and seed longevity of xerothermic grassland species was not intermediate but the shortest one. Ecological background of differences between hypotheses and experimental results are discussed. First record on seed bank type is reported here for 12 species: Dianthus pontederae, Digitalis grandiflora, Ferula sadleriana, Hieracium sylvaticum, Inula ensifolia, Jurinea mollis, Lychnis coronaria, Saponaria officinalis, Scorzonera austriaca, Secale sylvestre, Stipa borysthenica, Verbascum lychnitis.

2

Roadside habitats : the impact of salinization on the occurrence, growth and reproduction of two weed species Echinochloa crus-galli and Digitaria sanguinalis

100%

Novakova M. , Sera B. , Cudlin P.

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nr 3

3

Inhibitory effect of aqueous extracts from reed canary grass (Phalaris arundinacea L.) on the development of selected weed species

100%

Golebiowska H. , Kieloch R. , Topolski J.

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tom 20

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nr 4

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Dominant weeds in maize (Zea mays L.) cultivation and their competitiveness under conditions of various methods of weed control

80%

Glowacka A.

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tom 64

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nr 2

EN

A field experiment was conducted in the years 2008- 2010 at the Research Station of the Faculty of Agricultural Sciences, University of Life Sciences in Lublin, on brown soil with a slightly acidic pH, a high content of available phosphorus and potassium as well as an average magnesium content. The experiment was set up in a random split-plot design with four replications, with two methods for controlling weed infestation: I. mechanical – weeding of inter-rows twice; II. chemical – the herbicide Afalon Dyspersyjny 450 SC (a.i. linuron, 900 g×ha-1). Next, potassium, calcium and magnesium contents were determined in maize and in the dominant weed species. Based on the dry weight yield of maize and the biomass of particular weed species, nutrient uptake per hectare area was calculated. The chemical method of weed control reduced both the number and dry weight of weeds more than the mechanical method. The dominant species in the maize crop were Echinochloa crus-galli (L.) P. Beauv., Chenopodium album L., Galinsoga parviflora Cav., and Cirsium arvense L. All the weed species examined were more competitive than maize in accumulating potassium, calcium and magnesium. Galinsoga parviflora Cav. was the most competitive species with maize for potassium, Cirsium arvense L. for calcium, and Chenopodium album L. and Polygonum lapathifolium L. subsp. lapathifolium for magnesium. Weeds are serious competitors in taking up nutrients relative to crop plants; their share in the total uptake of macroelements from the soil by the maize crop and weeds together was considerable and it averaged as follows: for K – 35%, Ca – 27.3%, Mg –27.4%.

PL

Doświadczenie polowe przeprowadzono w latach 2008-2010 w Stacji Doświadczalnej Wydziału Nauk Rolniczych Uniwersytetu Przyrodniczego w Lublinie na glebie brunatnej o odczynie lekko kwaśnym, o bardzo wysokiej zasobności w fosfor i potas oraz średniej w magnez. Doświadczenie założono w układzie losowanych podbloków, w czterech powtórzeniach, uwzględniając dwie metody regulacji zachwaszczenia kukurydzy: I. mechaniczna – dwukrotne opielanie międzyrzędzi; II. chemiczna – herbicyd Afalon Dyspersyjny 450 EC (s.a. linuron, w dawce 900 g×ha-1). W kukurydzy i dominujących gatunkach chwastów oznaczono zawartość potasu, wapnia i magnezu. Na podstawie plonu suchej masy kukurydzy oraz biomasy poszczególnych gatunków chwastów wyliczono pobranie składników z powierzchni 1 ha. Chemiczna metoda regulacji zachwaszczenia ograniczała bardziej zarówno liczbę jak i suchą masę chwastów w porównaniu do zabiegów mechanicznych. Gatunkami dominującymi w uprawie kukurydzy były: Echinochloa crus-galli (L.) P Beauv., Chenopodium album L., Galinsoga parviflora Cav. i Cirsium arvense L. Wszystkie badane gatunki chwastów były bardziej konkurencyjne w gromadzeniu potasu, wapnia i magnezu niż rośliny kukurydzy. Gatunkiem najsilniej konkurującym o potas była Galinsoga parviflora Cav., o wapń – Cirsium arvense L., zaś o magnez – Chenopodium album L. i Polygonum lapathifolium L subsp. lapathifolium. Chwasty są groźnymi konkurentami w pobieraniu składników pokarmowych w stosunku do roślin uprawnych, ich udział w ogólnym pobraniu makroelementów z gleby przez łan kukurydzy był znaczny i wynosił średnio dla K – 35%, Ca – 27,3%, Mg –27,4%.