Search Results

You are looking at 41 - 50 of 140 items for :

  • "root architecture" x
  • Refine by Access: All x
Clear All
Free access

Conny W. Hansen, Jonathan Lynch, and Carl-Otto Ottosen

Whole-plant CO2 exchange and root-shoot interactions during transition from vegetative to reproductive growth of `Coral Charm' chrysanthemum (Dendranthema ×grandiflorum Ramat.) were investigated over a range of P concentrations considered to be deficient (1 μM), adequate (100 μM), or high (5 mM). Transition from vegetative to reproductive growth resulted in reduced photosynthate production, root respiration, biomass accumulation, and starch accumulation in leaves. Root respiration was low in high-P plants regardless of growth stage. Reduced root respiration may indicate changes in source-sink relationships during the transition from vegetative to reproductive growth, making roots less competitive sinks than developing flowers. Plant responses to P deficiency included decreased CO2 assimilation and shoot biomass accumulation but increased root respiration, root:shoot ratio, specific leaf mass (SLM), and starch accumulation in leaves. Reduced root respiration activity in high-P plants was presumably due to differences in root architecture resulting in proportionately fewer root apices in high P. Daily CO2 assimilation, shoot biomass, SLM, and root:shoot ratio were similar in plants grown with adequate-P and high-P availability, although plant P accumulation increased with P availability. Our results suggest that the excessive P fertilization often used in ornamental production systems is detrimental to root activity.

Free access

Christina Wells and Desmond Layne

We are using a minirhizotron camera system to observe fine root dynamics beneath irrigated and nonirrigated peach trees. Our long term goals are: 1) to relate the timing of fine root production to tree phenology, soil water content, and soil temperature; and 2) to determine how fine root architecture and demography differ between trees with and without supplemental irrigation. In early 2002, minirhizotrons were constructed and installed beneath each of 72 open-center, 4-year-old `Redglobe' peach trees at the Musser Fruit Research Farm near Clemson University. Beginning in May 2002, videotaped images from each minirhizotron were collected at 2-week intervals; notes on tree phenology were also recorded biweekly. Videotapes were digitized in the lab, and information on root length, diameter, appearance and longevity was extracted from the images. Soil temperature and volumetric water content were measured in the orchard throughout the growing season. In the 2 years following minirhizotron installation, irrigated trees allocated a significantly greater percentage of their fine root length to the upper soil layers and exhibited less root branching than nonirrigated trees. Fine roots produced by irrigated trees lived significantly longer: irrigated trees had a median root life span of 165 days, while nonirrigated trees had a median root life span of only 115 days (P< 0.001; proportional hazards regression). Fine roots from irrigated trees remained in the physiologically active “white” state for an average of 10 days longer than roots from nonirrigated trees (P< 0.001). Data from 2002–03 indicate that the trees produce new root flushes at least three times during the year, with a significant flush occurring immediately after harvest.

Free access

Ana Fita, Belén Picó, Rita C.S. Dias, and Fernando Nuez

, Pythium , Trichoderma , and Fusarium . In addition, root architecture after infection was also studied in all plants. The parameters used to evaluate root architecture were 1) root weight (g); 2) number of lateral roots; 3) root length (cm), usually

Free access

Jonathan P. Lynch

. Lynch, J. 2004 Optimization modeling of plant root architecture for water and phosphorus acquisition J. Theor. Biol. 226 331 340 Ho, M. Rosas, J. Brown, K. Lynch, J. 2005 Root

Open access

Arthur Villordon, Jeffrey Cole Gregorie, Don LaBonte, Awais Khan, and Michael Selvaraj

moisture availability on ‘Beauregard’ root architecture ( Villordon et al., 2012 , 2013 ), quantify drought effects on gene expression and storage root width and weight in ‘Beauregard’ ( Solis et al., 2014 ), and document the simultaneous effects of virus

Free access

Taryn L. Bauerle and Michela Centinari

, 1987 ; Guo et al., 2011 ; Pierret et al., 2007 ) and in some cases on a tree’s root architectural or morphological factors in response to the soil environment ( Comas and Eissenstat, 2004 ; Pregitzer, 2002 ). Rightly so, root system morphology and

Free access

Ana Fita, Cristina Esteras, Belén Picó, and Fernando Nuez

)-tolerant lines. Each cross step was followed by a selection for root architecture and resistance to MVD; a 5% to 10% selection pressure was applied. Description Lines 32349.8F 1 and 32349.8F 2 develop andromonoecious plants, intermediate in size

Open access

Mohammad Akbari, Hossein Hokmabadi, Mohsen Heydari, and Ali Ghorbani

mean separation. Arota has three to four main roots, with multiple fibrous lateral roots. The root architecture appears to be a combination of UCB1 and P. vera , the most common Iranian rootstock ( Akbari et al., 2018 ). The leaves of Arota are similar

Open access

Ute Albrecht, Shahrzad Bodaghi, Bo Meyering, and Kim D. Bowman

different root architectures arising from vegetative propagation will result in trees of inferior quality. The use of rooting hormones and the maturity of the source plant ( Ferguson et al., 1985 ) are additional sources of concern as they may affect growth

Free access

Maria A. Macias-Leon and Daniel I. Leskovar

of root hairs ( Kamula et al., 1994 ) leads to inefficient nutrient uptake, which may result in nutrient deficiencies ( Sullivan et al., 2001 ). Improving seed germination and root architecture may help to overcome nutrient and water limitations and