Search results for "shoot"

THE ROLE OF CYTOKININS AND ETHYLENE INHIBITORS ON LENTICEL HYPERTROPHY GENERATION AND ETHYLENE PRODUCTION IN IN VITRO CULTURES OF POPULUS EUPHRATICA …

1995

Populus euphratica Olivier is native to the Irano—Turanian areas (Middle East). Elche (Alicante province, SE Spain) is known to be its only European location. Nodal segments from root shoots were established in vitro in a Murashige and Skoog medium supplemented with several cytokinins. Ethylene inhibitors AgNO3 and CoCl2 were used in combination with kinetin. Hormone-free media supplemented with sucrose (20–60 mg 1−1) was also tested. Ethylene was measured by gas chromatography, and both the percentage of sprouting shoots and lenticel hypertrophy in cultures were recorded. Ethylene production was higher in cultures supplemented with cytokinins (especially with meta-topolin), with high sprou…

A morphogenetic role for ethylene in hypocotyl cultures of Digitalis obscura L.

1985

The effect of exogenously applied ethylene on organogenesis in Digitalis obscura L. hypocotyls cultured in vitro was studied. Interactions of this gas with other growth regulators was also tested. Ethylene by itself only promoted root formation. Shoot regeneration was obtained in presence of indoleacetic acid and kinetin. The addition of ethylene (10 ppm) increased the caulogenetic action of this medium; higher concentrations than 10 ppm reduced this response. Kinetin alone did not promote organogenesis and nullified the promotive effect of ethylene on rhizogenesis.

BEAM ELEMENT UNDER FINITE ROTATIONS

2021

The present work focuses on the 2-D formulation of a nonlinear beam model for slender structures that can exhibit large rotations of the cross sections while remaining in the small-strain regime. Bernoulli-Euler hypothesis that plane sections remain plane and perpendicular to the deformed beam centerline is combined with a linear elastic stress-strain law. The formulation is based on the integrated form of equilibrium equations and leads to a set of three first-order differential equations for the displacements and rotation, which are numerically integrated using a special version of the shooting method. The element has been implemented into an open-source finite element code to ease comput…

Evaluation of intra-cultivar variability in Olea europaea L. cv. Leccino using morphological, biochemical and molecular markers

2020

The phenotypic and genotypic variability of olive tree cv. Leccino (Olea europaea L.), an ancient cultivar from North-Central Italy, was investigated using 44 quantitative and qualitative agro-morphological traits, SDS-PAGE of seed proteins (storage proteins and tegument proteins) and molecular markers such as RAPDs (30 primers) and SSRs (8 primers). Fifteen accessions of Olea europaea catalogued as "Leccino" and one certified tree of "Leccino" (LESt) were examined. The plants were clonally propagated and the measuring of all morphological characteristics was conducted over a period of seven years. The ANOVA analysis showed that all accessions were homogenous for many traits while very few …

Differential competitive ability between sexes in the dioecious Antennaria dioica (Asteraceae)

2012

† Background and Aims Differences in competitive ability between the sexes of dioecious plants are expected as a result of allocation trade-offs associated with sex-differential reproductive costs. However, the available data on competitive ability in dioecious plants are scarce and contradictory. In this study sexual competition was eval- uated using the dioecious plant Antennaria dioica in a common garden transplantation experiment. † Methods Male and female plants were grown for 3 years either in isolation, or in competition with a plant of the same sex or the opposite sex. Flowering phenology, sexual and asexual reproduction, plant growth, nutrient content and arbuscular mycorrhizal col…

TWO YEARS OF STUDIES INTO NATIVE BERMUDAGRASS (CYNODON SPP.) GERMPLASM FROM SICILY (ITALY) FOR THE CONSTITUTION OF TURF CULTIVARS

2008

Bermudagrass (Cynodon spp.) is the most widely used warm season turf species in the world for sport, lawn and utility turfs. The species is widespread in Sicily (Italy) where it exhibits a large range of diverse morphological characteristics due to a long process of adaptation to varying climatic and soil conditions of the island. In order to exploit the bermudagrass genetic resources and establish a germplasm bank for use in various plant breeding programmes, bio-agronomic evaluation tests were carried out on the 40 Sicilian biotypes of Cynodon spp. from 2002 to 2004 at the experimental farm “Orleans”, University of Palermo. The accessions were compared to the standard cultivar ‘Savannah’,…

A comparative analysis of genetic variation in rootstocks and scions of old olive trees – a window into the history of olive cultivation practices an…

2014

Background Past clonal propagation of olive trees is intimately linked to grafting. However, evidence on grafting in ancient trees is scarce, and not much is known about the source of plant material used for rootstocks. Here, the Simple Sequence Repeat (SSR) marker technique was used to study genetic diversity of rootstocks and scions in ancient olive trees from the Levant and its implications for past cultivation of olives. Leaf samples were collected from tree canopies (scions) and shoots growing from the trunk base (suckers). A total of 310 trees were sampled in 32 groves and analyzed with 14 SSR markers. Results In 82.7% of the trees in which both scion and suckers could be genotyped, t…

CRYOPRESERVATION OF PEACH SHOOT TIPS BY ENCAPSULATION DEHYDRATION

2011

Micropropagation ofAgeratum houstonianumby nodal segments

2017

Ageratum houstonianum is a bedding and flowering potted plant originated from Central America which is generally propagate by seed. In this report a preliminary in vitro technique for propagation of A. houstonianum was investigated. In vitro germinated seeds were used to establish aseptic shoot cultures of several clones. Seedling stem segments bearing 3-4 nodes were placed on Murashige and Skoog (MS) basal medium plus 20 g L-1 sucrose, 8.0 g L-1 Agar to induce axillary shoot development. Axillary shoots were subcultured into the same medium and nodal segments were sectioned and subcultured to increase the stock of shoot cultures. Shoot cultures of the selected clone AG14 were used to accom…

COLLARD GREEN (BRASSICA OLERACEA VAR. ACEPHALA) CULTIVATION IN SICILY

2013

Collard greens (Brassica oleracea var. acephala) are a group of plants cultivated for its thick, slightly bitter, edible leaves. As other Brassicaceae, have a good nutritional value as they are a good sources of vitamin C and soluble fiber, and contain various compounds with potent anticancer properties. In order to enhance collard cultivation in Sicily, different planting dates were tested. The research was carried out during 2009-2010 in the experimental field of SAgA Department – University of Palermo. Plants of a Sicilian local cultivar, with high vigor, good emission of side shoots, large and moderately curly leaves and long and strong petiole, were planted in three different periods: …