Search results for "Dwarfing"
showing 9 items of 9 documents
The WtmsDW Locus on Wheat Chromosome 2B Controls Major Natural Variation for Floret Sterility Responses to Heat Stress at Booting Stage
2021
Heat stress at booting stage causes significant losses to floret fertility (grain set) and hence yield in wheat (Triticum aestivum L.); however, there is a lack of well-characterized sources of tolerance to this type of stress. Here, we describe the genetic analysis of booting stage heat tolerance in a cross between the Australian cultivars Drysdale (intolerant) and Waagan (tolerant), leading to the definition of a major-effect tolerance locus on the short arm of chromosome 2B, Wheat thermosensitive male sterile Drysdale/Waagan (WtmsDW). WtmsDW offsets between 44 and 65% of the losses in grain set due to heat, suggesting that it offers significant value for marker-assisted tolerance breedin…
Estimating the dwarfing rate of an extinct Sicilian elephant.
2021
Summary Evolution on islands, together with the often extreme phenotypic changes associated with it, has attracted much interest from evolutionary biologists. However, measuring the rate of change of phenotypic traits of extinct animals can be challenging, in part due to the incompleteness of the fossil record. Here, we use combined molecular and fossil evidence to define the minimum and maximum rate of dwarfing in an extinct Mediterranean dwarf elephant from Puntali Cave (Sicily). 1 Despite the challenges associated with recovering ancient DNA from warm climates, 2 we successfully retrieved a mitogenome from a sample with an estimated age between 175,500 and 50,000 years. Our results sugge…
Expression of PIP1 and PIP2 aquaporins is enhanced in olive dwarf genotypes and is related to root and leaf hydraulic conductance
2007
The expression of OePIP1.1 and OePIP2.1 aquaporins in root, stem and leaf was higher in Olea europaea L. (olive) plants carrying a dwarfing (D) clone as rootstock, than in plants carrying a vigorous (M) clone as rootstock. The highest difference of expression between plants with D and M rootstocks was detected in the root and for the PIP2 gene, the transcripts of which show a high water channel activity in oocytes. Compared with plants with M rootstock, plants with D rootstock showed reduced root and canopy biomass and reduced hydraulic conductance of the bulk root system (Kroot). Hydraulic conductance of D roots was higher than that of M roots when Kroot was scaled by root DW, in agreemen…
Physiological advantages of dwarfing in surviving extinctions in high-CO2 oceans
2015
Excessive CO 2 in the present-day ocean-atmosphere system is causing ocean acidification, and is likely to cause a severe biodiversity decline in the future, mirroring effects in many past mass extinctions. Fossil records demonstrate that organisms surviving such events were often smaller than those before, a phenomenon called the Lilliput effect. Here, we show that two gastropod species adapted to acidified seawater at shallow-water CO 2 seeps were smaller than those found in normal pH conditions and had higher mass-specific energy consumption but significantly lower whole-animal metabolic energy demand. These physiological changes allowed the animals to maintain calcification and to parti…
Hydraulic kinetics of the graft union in different Olea europaea L. scion/rootstock combinations
2007
The hydraulic resistance of young olive trees grafted on rootstocks with contrasting size-controlling potential was measured 30, 90, 360 and 480 days after grafting. Olive (Olea europaea L.) clones inducing plant vigorous growth (Leccino ‘Minerva’, LM) or dwarfing (Leccino ‘Dwarf’, LD) were studied in different scion/rootstock combinations (LD/LD, LD/LM, LM/LD, LM/LM). Plants growing on LD root systems developed lower leaf surface areas (about 50% less) than plants grafted on LM rootstocks. Graft union represented the largest fraction (up to 85%) of whole-plant hydraulic resistance 30 days after grafting, and still represented an important fraction of it 2 months later (40–55%). Four-hundre…
The effect of different vigour olive clones on growth, dry matter partitioning and gas exchange under water deficit
2012
Abstract In the last decade, high-density olive planting systems have been developed to facilitate less costly mechanical harvesting and pruning by using straddle harvesters. High-density orchards allow faster production since the first crop of fruit starts a few years after planting. In high-density orchards the control of tree size is essential. It is possible to control the vigour and size of the tree by selecting suitable cultivars, by choosing rootstocks capable of controlling scion vigour and, finally, by applying deficit irrigation to reduce plant vegetative growth. Knowledge of tree water requirements is needed for precise irrigation scheduling. In this study, the dwarfing capacity …
Is rootstock-induced dwarfing in olive an effect of reduced plant hydraulic efficiency?
2006
We investigated the hydraulic architecture of young olive trees either self-rooted or grafted on rootstocks with contrasting size-controlling potential. Clones of Olea europea L. (Olive) cv ''Leccino'' inducing vigorous scion growth (Leccino ''Minerva'', LM) or scion dwarfing (Leccino ''Dwarf'', LD) were studied in different scion/rootstock combinations (LD, LM, LD/LD, LM/LM, LD/LM and LM/LD). Shoots growing on LD root systems developed about 50% less leaf surface area than shoots growing on LM root systems. Root systems accounted for 60-70% of plant hydraulic resistance (R), whereas hydraulic resistance of the graft union was negligible. Hydraulic conductance (K = 1/R) of LD root systems w…
LOW VIGOR PEACH × ALMOND ROOTSTOCKS FOR INTENSIVE PEACH PLANTINGS IN MEDITERRANEAN ENVIRONMENTS
2014
A three-year trial was carried out to evaluate the vegetative and productive performance of five peach rootstocks of varied vigor. The study was conducted in south-western Sicily using 45 V-trained trees of 'Tropic Snow' peach planted in 2005 and grafted on GF677 and four low-vigor rootstocks selected at the Department of Agricultural, Food and Environmental Sciences, University of Pisa, namely IS5/8 (Polluce), IS5/19 (Castore), IS5/23, IS5/29. Trunk circumference, winter and summer pruning weight, number and mass of fruit were recorded from 2010 to 2012. All IS selections reduced trunk cross-sectional area (TCSA) and pruning weight compared to GF677 with IS5/23 inducing the highest reducti…
Defining the Island Dwarfing Rate of an Extinct Sicilian Elephant Using Ancient DNA
2020
Evolution on islands, and the often extreme phenotypic changes associated with it, has attracted much interest from evolutionary biologists. However, measuring the rate of change of a particular phenotypic trait of extinct animals can be challenging, due to the incompleteness of the fossil record. Here, we use combined molecular and fossil evidence to define the minimum and maximum rate of dwarfing in an extinct Mediterranean dwarf elephant from Puntali Cave (Sicily). Despite the challenges associated with recovering ancient DNA from warm climates, we successfully retrieved a mitogenome from a sample with an estimated age between 147,000 and 50,000 years. Our results suggest that this speci…