scholarly journals The influence of mechanical resistance and phosphate supply on morphology and function of maize roots.

1982 ◽  
Vol 30 (3) ◽  
pp. 179-192 ◽  
Author(s):  
F.R. Boone ◽  
B.W. Veen
Keyword(s):  
Root Growth ◽  
Shoot Growth ◽  
Sandy Loam ◽  
Specific Root Length ◽  
Mechanical Resistance ◽  
P Availability ◽  
Low Light ◽  
Maize Roots ◽  
And Function ◽  
Different Levels

In 3 pot experiments, maize cv. Avanti was grown on a marine sandy loam compacted to different pore vol. and supplied with different rates of P. Root wt. was not changed by different levels of mechanical resistance but root extension growth and cone resistance were curvilinearly related. At high mechanical resistance, root growth was more horizontal; vertical root growth was very limited at high cone resistances. Specific root length was also smaller, root diam. larger and fewer laterals/cm main root were developed although their av. length was not affected. The influence of mechanical resistance on root distribution and morphology reduced nutrient uptake and therefore shoot growth. With low P availability, P limited shoot growth more the higher the mechanical resistance. With sufficient P, K had the same effect. If an aboveground factor such as a low light intensity limited shoot growth, mechanical resistance had no effect on shoot growth. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals 355 REDUCING MECHANICAL IMPEDANCE OF ROOTS IN COMPACTED SOILS INCREASES ROOT AND SHOOT GROWTH

HortScience ◽  
1994 ◽  
Vol 29 (5) ◽  
pp. 481e-481
Author(s):  
Susan D. Day ◽  
Nina L. Bassuk
Keyword(s):  
Root Growth ◽  
Shoot Growth ◽  
Sandy Loam ◽  
Mechanical Impedance ◽  
Compacted Soils ◽  
Vertical Drains ◽  
Pyrus Calleryana ◽  
Vertical Drainage ◽  
Root And Shoot Growth ◽  
Surrounding Soil

Four techniques for compaction amelioration were studied: 1) Vertical drainage panels; 2) vertical gravel-filled sump drains; 3) soil trenches filled with sandy loam; and 4) peat amended back fill. The control was backfilled with existing soil on the site. Vertical drainage mats and vertical gravel-filled sump drains were shown to increase O2% in surrounding soil; however, all O2 levels regardless of treatment were above what is considered limiting. Shoot and root growth of Pyrus calleryana `Redspire' was greatest for treatments that alleviated mechanical impedance (soil trenches and amended back fill) and least for treatments that did not (controls and vertical drains). Vertical drainage mats which alleviated mechanical impedance to a lesser degree showed intermediate growth.

scholarly journals Evaluation of commercial inorganic and organic fertilizer effects on arbuscular mycorrhizae formed by Glomus intraradices

2004 ◽  
Vol 14 (2) ◽  
pp. 196-202 ◽  
Author(s):  
R.G. Linderman ◽  
E.A. Davis
Keyword(s):  
Root Growth ◽  
Arbuscular Mycorrhizae ◽  
Glomus Intraradices ◽  
Sandy Loam ◽  
Organic Fertilizer ◽  
Am Fungi ◽  
Organic Fertilizers ◽  
Main Element ◽  
Growth Responses ◽  
And Function

Formation and function of arbuscular mycorrhizae (AM) are affected by levels of fertility in soil or fertilizers applied to soilless container mixes. For AM fungi, phosphorus (P) is the main element influencing colonization of host plant roots. The question addressed in this study was whether inorganic or organic fertilizers were more compatible with the formation and function of AM. Several controlled-release inorganic (CRI) fertilizers were compared with several organic (OR) fertilizers at different rates (½× to 4× the recommended rate) to determine (1) threshold levels of tolerance by the AM fungus Glomus intraradices in relation to root colonization, and (2) growth responses of `Guardsman' bunching onion (Allium cepa) and `Orange Cupido' miniature rose (Rosa spp.) plants grown in a soilless potting mix or sandy loam soil. AM colonization in soil was greatly decreased or totally inhibited by CRI fertilizers with high P content at the 2× rate or greater, whereas colonization was decreased but never eliminated by low-P OR fertilizers at the 3× rate or greater. Shoot growth of onions was similar with or without AM inoculation when fertilized with CRI, but in general was only enhanced by OR fertilizers if inoculated with AM fungi, compared to the noninoculated controls. Shoot and root growth of onions were significantly increased by AM inoculation when OR fertilizers were used at the 1× rate. In contrast, root growth was not increased by the combination of CRI fertilizers and AM fungal inoculation. Inoculation of miniature roses grown in sandy loam amended with 25% peat and perlite and fertilized with all the CRI or OR fertilizers resulted in high AM colonization, but without much AM-induced growth increase except where OR fertilizers or CRI fertilizers with low P were used. In a soilless potting mix, growth of miniature roses was less with OR fertilizers at the rates used than CRI fertilizers, but mycorrhiza formation was greater in the former unless P was low in the latter. These results indicate that release of nutrients from organic fertilizers, as a result of microbial activity, favors AM establishment and function more than most inorganic fertilizers unless P levels of the latter are low.

scholarly journals 298 Root Restriction and Fertilizer Effects on Young Peach Trees

HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 494A-494 ◽  
Author(s):  
T. Daw ◽  
T.J. Tworkoski ◽  
D.M. Glenn
Keyword(s):  
Root Growth ◽  
Root Length ◽  
Shoot Growth ◽  
Prunus Persica ◽  
Specific Root Length ◽  
Nonwoven Fabric ◽  
Soil Conditions ◽  
Root Weight ◽  
Root Volume ◽  
Peach Trees

Shoot growth of peach trees can be managed by manipulating edaphic conditions such as root volume and soil fertility. In this experiment, 2-year-old peach trees (Prunus persica L. cv. Sentry on `Lovell' rootstock) were planted in pots with a split root design, so that half the roots were not treated and the other half received one of four treatments: root volume restricted with polypropylene nonwoven fabric (FAB), fertilizer alone (FER), FAB + FER, and untreated control (UTC). Total shoot growth and root growth were measured, and root growth in the split halves was compared. FER increased leaf number and weight by 48% and 60%, respectively, but not stem growth. Leaf nitrogen concentration and photosynthesis were greatest in FER treatment. FAB did not affect shoot weight or reduce total root weight or length, although roots did not grow past the fabric barrier. FER increased root weight and length (116% and 57%, respectively, compared to UTC) on the treated half but did not affect root growth on the untreated half. Greatest root growth occurred in the root half that received FAB + FER, particularly in the 5-cm soil segment proximal to the fabric (4.6 cm•cm-3 compared to 0.8 cm.cm-3 in UTC). Shoot length was greater in FAB + FER than FAB. Thus, fertilizer applied near fabric increased root growth and the combination of fertilizer and fabric may be used to regulate shoot growth. Specific root length (root length per gram dry weight) was highest in trees with no treatment, suggesting root acclimation to low nutrient soil conditions. Lower specific root length resulted in soils that were fertilized. The results indicate that nonwoven fabric restricts root growth in peach trees and reduces shoot elongation. The combined effect of fabric plus selected application of fertilizer may be used to regulate growth of peach trees.

Understanding the root sink.

2022 ◽  
pp. 59-66
Author(s):  
T. M. DeJong
Keyword(s):  
Root Growth ◽  
Root Development ◽  
Apical Meristem ◽  
Shoot Growth ◽  
Lateral Roots ◽  
Fruit Trees ◽  
Extension Growth ◽  
Factors Affecting ◽  
And Function ◽  
Shoot Meristems

Abstract Root development and growth is similar to shoot growth in that extension growth is initiated by an apical meristem and girth growth of mature roots is carried out by the vascular cambium. However, the initiation of lateral roots is entirely different than the initiation of lateral leaves or shoot meristems. This chapter deals with understanding the root sink in fruit trees by studying root growth, including the initiation of lateral roots, root classification according to size and function, factors affecting their growth, and rootstocks.

Sex-specifically responsive strategies to phosphorus availability combined with different soil nitrogen forms in dioecious Populus cathayana

2021 ◽  
Author(s):  
Xiucheng Liu ◽  
Yuting Wang ◽  
Shuangri Liu ◽  
Miao Liu
Keyword(s):  
Root Length ◽  
Root Length Density ◽  
Specific Root Length ◽  
P Uptake ◽  
Root Tip ◽  
P Availability ◽  
P Deficiency ◽  
Populus Cathayana ◽  
Leaf P ◽  
P Supply

Abstract Aims Phosphorus (P) availability and efficiency are especially important for plant growth and productivity. However, the sex-specific P acquisition and utilization strategies of dioecious plant species under different N forms are not clear. Methods This study investigated the responsive mechanisms of dioecious Populus cathayana females and males based on P uptake and allocation to soil P supply under N deficiency, nitrate (NO3 −) and ammonium (NH4 +) supply. Important Findings Females had a greater biomass, root length density (RLD), specific root length (SRL) and shoot P concentration than males under normal P availability with two N supplies. NH4 + supply led to higher total root length, RLD and SRL but lower root tip number than NO3 − supply under normal P supply. Under P deficiency, males showed a smaller root system but greater photosynthetic P availability and higher leaf P remobilization, exhibiting a better capacity to adaptation to P-deficiency than females. Under P deficiency, NO3 − supply increased leaf photosynthesis and PUE but reduced RLD and SRL in females while males had higher leaf P redistribution and photosynthetic PUE than NH4 + supply. Females had a better potentiality to cope with P deficiency under NO3 − supply than NH4 + supply; the contrary was true for males. These results suggest that females may devote to increase in P uptake and shoot P allocation under normal P availability, especially under NO3 − supply, while males adopt more efficient resource use and P remobilization to maximum their tolerance to P-deficiency.

scholarly journals Root growth and function of three Mojave Desert grasses in response to elevated atmospheric CO2 concentration

2000 ◽  
Vol 145 (2) ◽  
pp. 245-256 ◽  
Author(s):  
C. K. YODER ◽  
P. VIVIN ◽  
L. A. DEFALCO ◽  
J. R. SEEMANN ◽  
R. S. NOWAK
Keyword(s):  
Root Growth ◽  
Mojave Desert ◽  
Co2 Concentration ◽  
Atmospheric Co2 ◽  
Elevated Atmospheric Co2 ◽  
Atmospheric Co2 Concentration ◽  
And Function ◽  
Desert Grasses

Effect of silicon on root growth, ionomics and antioxidant performance of maize roots exposed to As toxicity

2021 ◽  
Author(s):  
Adriana Mišúthová ◽  
Ľudmila Slováková ◽  
Karin Kollárová ◽  
Marek Vaculík
Keyword(s):  
Root Growth ◽  
Maize Roots ◽  
As Toxicity

scholarly journals Phosphorus extracted by ion exchange resins and mehlich-1 from oxisols (latosols) treated with different phosphorus rates and sources for varied soil-source contact periods

2013 ◽  
Vol 37 (3) ◽  
pp. 667-677 ◽  
Author(s):  
Irio Fernando de Freitas ◽  
Roberto Ferreira Novais ◽  
Ecila Mercês de Albuquerque Villani ◽  
Sarah Vieira Novais
Keyword(s):  
Sandy Loam ◽  
Extraction Methods ◽  
Available P ◽  
Molar Ratio ◽  
P Availability ◽  
Triple Superphosphate ◽  
Experimental Conditions ◽  
Reactive Phosphate ◽  
Exchange Resins ◽  
P Sources

Despite the large number of studies addressing the quantification of phosphorus (P) availability by different extraction methods, many questions remain unanswered. The aim of this paper was to compare the effectiveness of the extractors Mehlich-1, Anionic Resin (AR) and Mixed Resin (MR), to determine the availability of P under different experimental conditions. The laboratory study was arranged in randomized blocks in a [(3 x 3 x 2) + 3] x 4 factorial design, with four replications, testing the response of three soils with different texture: a very clayey Red Latosol (LV), a sandy clay loam Red Yellow Latosol (LVA), and a sandy loam Yellow Latosol (LA), to three sources (triple superphosphate, reactive phosphate rock from Gafsa-Tunisia; and natural phosphate from Araxá-Minas Gerais) at two P rates (75 and 150 mg dm-3), plus three control treatments (each soil without P application) after four contact periods (15, 30, 60, and 120 days) of the P sources with soil. The soil acidity of LV and LVA was adjusted by raising base saturation to 60 % with the application of CaCO3 and MgCO3 at a 4:1 molar ratio (LA required no correction). These samples were maintained at field moisture capacity for 30 days. After the contact periods, the samples were collected to quantify the available P concentrations by the three extractants. In general, all three indicated that the available P-content in soils was reduced after longer contact periods with the P sources. Of the three sources, this reduction was most pronounced for triple superphosphate, intermediate for reactive phosphate, while Araxá phosphate was least sensitive to the effect of time. It was observed that AR extracted lower P levels from all three soils when the sources were phosphate rocks, while MR extracted values close to Mehlich-1 in LV (clay) and LVA (medium texture) for reactive phosphate. For Araxá phosphate, much higher P values were determined by Mehlich-1 than by the resins, because of the acidity of the extractor. For triple superphosphate, both resins extracted higher P levels than Mehlich-1, due to the consumption of this extractor, particularly when used for LV and LVA.

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