Attempts were made during the 1990 growing season to induce somatic embryos from non-zygotic tissues of five economically important walnut cultivars. The following explants were employed: fertilized and unfertilized ovules; immature and mature catkins; abnormal "spike" flowers; and in vitro-grown leaves and roots. Modifications of the standard induction media were also examined. These included ...

In June, 2021, laurel willow ( Salix pentandra ) near Slave Lake, Alberta, was found to be infected by a Melampsora sp. that produced bright yellow urediniospores in uredia were present on catkins, leaves, and stems. All species previously reported Canada are recorded as infecting leaves; therefore, further investigation undertaken ascertain the identity of this pathogen. To assess relationship...

From 1996 to 2002 the monthly litterfall in a Quercus suber forest ecosystem of Montseny (NE Spain) was recorded and its relationship to meteorological variables was statistically analysed. The average annual production (477 g m−2 yr−1) was similar to those found in other Mediterranean evergreen forests with relatively high rainfall. The main components were the leaves (55% of the total biomass...

Abstract Plant migration and gene flow from genetically-modified or exotic trees to nearby lands by crossing with wild relatives is a major public regulatory concern. Many genetic strategies exist mitigate potential flow, however, the long delay in onset of flowering severe constraint research progress. We used heat-induced-FT-overexpression speed assessment expected floral phenotypes after CRI...

most of walnut production in iran comes from seed originated trees with low quality and quantity as product. for breeding new cultivar(s), from 1983 selection of iranian walnut germplasm was started at seed and plant improvement institute and at the first phase 117 genotypes were collected. seedlings of these genotypes were planted in kamalshahr (karaj), torogh, kahriz and bastam horticultural ...

although self incompatibility in walnut has not been reported, but the dicogamy limits self pollination of walnut cultivars. as the density of female flowers produced by the tree is low, if a high fruit set occurs, yield especially in terminal bearing cultivars will not be high. so breeding of a pollinizer cultivar with proper pollen shading period is highly necessary for increasing fruit produ...

 In 2007 and 2008, the influence of pollen source on the shell and kernel traits of resulting seeds and on fruit set was examined to evaluate the potential for Xenia or Metaxenia in Persian walnut. Pistillate flowers of ‘Jamal’, ‘Chandler’, ‘Hartley’ and ‘Pedro’ were crossed with the pollen of ‘Serr’, ‘Z60’ and ‘Damavand’. The pistillate flowers on each female parent were covered about one week...

in 2007 and 2008, the influence of pollen source on the shell and kernel traits of resulting seeds and on fruit set was examined to evaluate the potential for xenia or metaxenia in persian walnut. pistillate flowers of ‘jamal’, ‘chandler’, ‘hartley’ and ‘pedro’ were crossed with the pollen of ‘serr’, ‘z60’ and ‘damavand’. the pistillate flowers on each female parent were covered about one week ...

Shrubs have expanded in Arctic ecosystems over the past century, resulting in significant changes to albedo, ecosystem function, and plant community composition. Willow and rock ptarmigan (Lagopus lagopus, L. muta) and moose (Alces alces) extensively browse Arctic shrubs, and may influence their architecture, growth, and reproduction. Furthermore, these herbivores may alter forage plants in suc...