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We investigated the effects of sexual reproduction on vegetative propagation and relative somatic cost in Arum maculatum L. (Araceae). Two groups were selected as control and experimental. The spadices of individuals in experimental group were removed to test the relationship between sexual reproduction and vegetative propagation. Statistically significant differences were found between initial and final tuber weight in individuals with sexual organs removed. No significant differences were found between initial and final tuber weight in naturally reproducing (sexual organs not removed) individuals. However, the statistically significant differences were found between control and experimental group with respect to above-ground biomass but not in terms of below-ground biomass. The differences between two groups in terms of above-ground and below-ground nitrogen concentrations were also significant. Relative somatic cost of sexual reproduction (RSC) was observed in above-ground parts, but not in below-ground parts in terms of biomass and in both above- and below-ground parts in terms of nitrogen concentration.
In this study, we present investigations of morphological changes in the inflorescence of bolting Allium sativum L., which forms umbel-like inflorescences with small, inconspicuous flowers, bulbils, and leaf-like membranous bracts. Particular attention was focused on the architecture of a single flower, and the full sequence of developmental events and the differentiation of flower elements and inflorescence were traced. During the several-year long investigations of the garlic species, we observed that all inflorescence elements emerged chaotically, taking a completely random place in the inflorescence receptacle and it was impossible to identify the sequence of formation of the individual inflorescence elements. The absence of regular phyllotaxis and the specific sequence of formation of inflorescence elements are characteristic for inflorescence reversion. Since domesticated garlic has lost the capacity for sexual reproduction, it has probably evolved alternative reproduction modes in its developmental strategy, which is reflected by the formation of numerous bulbils (vegetative buds, topsets) in the inflorescence. This is one of the forms of reproductive strategy of the species, which through domestication progresses from sexual to asexual reproduction.
Rootability of Dalbergia sissoo Roxb. cuttings of mature tree originated clonal hedge bed were tested and compared to the same from seedling originated hedge bed. Mature tree originated cuttings were found potential for rooting in low-cost non-mist propagator without any rooting hormone. Steckling growth in nursery and in the field was found promising which is a complete indication for its successful application by tree planters. It will be a new research avenue to get disease free germplasm for the frustrated plantation managers and scientists due to die back of this tree through out the South Asian region.
So far, experience in the existing clonal seed orchards of Douglas-fir indicates that grafts of this species are short-lived. According to research carried out in North America, incompatibility between the grafted scions and the rootstocks happens during the whole period of growth and development in clonal seed orchards of Douglas-fir. A similar phenomenon occurs in the clonal seed orchards of Douglas-fir in Poland. The extent of die-back of grafts was examined in three existing oldest units in the Forest District of Gniewkowo (founded in 1992-1993; 2.80 ha), the Forest District of Leżajsk (founded in 1995, 4.22 ha) and the Forest District of Łopuchówko (founded in 1993, 7.43 ha). In all these areas, losses due to die-back ranged from a dozen to a few dozen per cent. Die-backs in the clonal seed orchards in the Forest District of Gniewkowo and in the Forest District of Łopuchówko are now reduced to as much as about fourty per cent of grafts. Analyses of die-back in all these areas reveal great variation between individual clones, indicating its genetic basis. Research carried out so far has not demonstrated the presence of any pathogens responsible for causing the die-back in the grafts. Some hope to solve the problem mentioned above arises from attempts at autovegetative propagation of Douglas-fir.
Rhizogenesis was stimulated in Kalmia angustifolia cuttings by auxins and fungicides in dust preparations. Satisfactory results were obtained for the combination of 0,5% indolebutyric acid (IBA) and Captan in talcum powder. The optimum time for taking the cuttings was the peak of the flowering period of mother plants. The best rooting medium was mixture of pine bark compost and peat (1:2).
Cis pospolity (Taxus baccata L.) na terenie Polski występuje na stanowiskach naturalnych w 33 rezerwatach. Może być odnawiany naturalnie lub sztucznie poprzez rozmnażanie generatywne lub wegetatywne. W Nadleśnictwie Kaliska prowadzone są badania nad restytucją cisa do lasu. Od 1998 roku wysadzono około 4000 sadzonek na 26 powierzchniach w leśnictwach.
Badano 54 odmiany piwonii chińskiej w pierwszym i drugim roku po podziale i przesadzeniu. Rośliny powstały w wyniku tradycyjnego podziału osobników matecznych w sierpniu 2002 roku. Na poletkach 1 m² posadzono po 4 rośliny poszczególnych odmian. Oceniono ich wzrost i kwitnienie w latach 2003 i 2004. Podział ten okazał się korzystny dla wszystkich odmian. Po dwóch latach uprawy rośliny każdej odmiany osiągnęły właściwe jej cechy. W pierwszym roku (2003) najdłużej - 92 dni rosły odmiany ‘Avalanche’ i ‘Mlle Rousseau’, a w drugim (2004) - 106 dni - ‘Avalanche’ i ‘Mme Vatryl' oraz 105 dni - ‘Baroness Schröder’. Najwyższe i gęsto ulistnione w obydwóch latach były odmiany ‘Conquette’, ‘Dermonth’ i ‘Adolphe Rousseau’, a najniższą ‘Albert Crousse’. W 2003 roku najobficiej kwitły odmiany ‘Compt de Niepperg’ i ‘Dermonth’, a w 2004 roku ‘Lady Anna’ i ‘Jadwiga’. Największe kwiaty o średnicy przeszło 14 cm w obydwóch latach miała odmiana ‘Torpilleur’, Czas trwania kwitnienia zależał od odmiany i przebiegu pogody. W obydwóch latach do najdłużej kwitnących należała odmiana ‘Avalanche’, a do najkrócej ‘Prof. Wóycicki’. Kwitnienie wszystkich odmian trwało około 30 dni. Do uprawy w polu na kwiaty cięte można zalecać odmiany ‘Albatre’, ‘Dorchester’, ‘Empereur Nicholas’, ‘Mlle Leonie Calot’, ‘Baroness Schröder’, ‘Jadwiga’, ‘Mme Vatryl’ i ‘Ursyn Niemcewicz’.
Celem pracy było określenie warunków mikrorozmnażania kocanek piaskowych. Na etapie namnażania stwierdzono istotny wpływ zastosowanego poziomu BA na liczbę pędów otrzymanych z jednego eksplantatu, natomiast wpływ pożywki podstawowej był nieistotny. Na pożywce MS z dodatkiem 1,0 mg·dm⁻³ BA uzyskano 17,59 pędów z jednego eksplantatu. Kocanki w zastosowanych warunkach ukorzeniały się w 96-100%. Świeża masa mikrosadzonek, długość ich pędów i korzeni, zależała od stężenia BA w pożywce zastosowanej do namnażania. Ponad 90% wysadzonych w szklarni sadzonek zaadaptowało się do warunków ex vitro. Po 10 tygodniach uprawy w szklarni rośliny silnie się rozkrzewiły wytwarzając średnio od 6,8 do 11,6 rozgałęzień. Obserwowano także wytwarzanie odrostów korzeniowych.
Bases of young shoots were treated with the Ukorzeniacz B2, preparation stimulating adventitious roots development. Then piles of a mixture of white peat and hortisol were made around the shoots. The shoot growth was accompanied by increasing the height of piles. After one vegetative period the rooted layers were removed off from half of the piled plants, and after two vegetative periods – from the other plants. The quality of the rooted layers was estimated and in spring 1998 and 1999 new plants grew from them. On average 85.2% of Paeonia lactiflora Pall. shoots piled over one vegetative period, and 75% of those piled over two vegetative periods took roots. A higher rooting quality was recorded in two-year layers. Regardless of the piling period, new plants were developed from the all rooted layers in ‘Avelanche’, ‘Lady Dormouth’ and ‘Reine Hortense’ cultivars. These and other cultivars whose layers rooted in over 70% cases, i.e. ‘Baroness Schröder’, ‘La Rosière’, ‘Marechal McMahon’, ‘Monsieur Jules Elie’, ‘Profesor Wóycicki’, ‘Thérèse’ and ‘Ursynów’, can be propagated with vertical layers.
In order to improve vegetative propagation of Berberis thunbergii ‘Red Rocket’, stock plants were subjected to shading and IBA treatment, as well as to the application of two commercially available rooting powders. Spraying stock plants with IBA 24 hours prior to cutting harvest gave the effect comparable to the use of rooting powders. Reduction of light intensity by 50 % and 96 % of ambient prior to harvest of cuttings improved rooting. Positive effect of shading results in changes in shoot anatomy, i.e. a weaker sclerenchyma development. Enhanced rooting in cuttings from shoots grown under reduced light intensity was accompanied by a decrease in the concentration of soluble proteins and by an increase in total chlorophyll content while the concentration of total soluble sugars remained unaffected.
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