Soil Organisms Influence Fine Root Lifespan in Peach

Damage to the root system by soil insects and pathogenic fungi is difficult to assess and often goes unnoticed until a tree exhibits significant decline above ground. In this study, below-ground imaging technology was used to quantify fine root turnover in peach and to determine what percentage of root death may be caused by soil pests in an apparently healthy orchard. The study was conducted on six 15-year-old `Loring' peach trees on Halford rootstock in Kearneysville, W.Va. Five root observation tubes were placed in the soil beneath each tree in Apr. 1996. Each tube was randomly assigned one of five soil drench treatments: Lorsban 4E insecticide, Ridomil 2E fungicide, a combination of both pesticides, 1/10th strength Hoagland's solution, or water. A portable VCR and camera system were used to record images of fine roots (<1 mm diameter) growing along the tubes at biweekly intervals from May 1996 through Nov. 1997. The images were used to construct a database of life history information for more than 1500 individual roots. Peach root survivorship was influenced by root diameter and pesticide treatment. Fine roots on tubes receiving either of the pesticide treatments had higher survivorship than roots on control tubes for all diameter classes. The effect was most pronounced for white roots <0.5 mm in diameter, whose survivorship during the growing season was increased by 45% when both insecticide and fungicide were applied. These results suggest that a substantial fraction of fine root death may be caused by interactions with the soil fauna.

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CARBON AND NUTRIENT CYCLING THROUGH FINE ROOTS IN RUBBER (HEVEA BRASILIENSIS) PLANTATIONS IN INDIA

Experimental Agriculture ◽

10.1017/s0014479713000203 ◽

2013 ◽

Vol 49 (4) ◽

pp. 556-573 ◽

Cited By ~ 6

Author(s):

M. D. JESSY ◽

P. PRASANNAKUMARI ◽

JOSHUA ABRAHAM

Keyword(s):

Soil Moisture ◽

Nutrient Cycling ◽

Fine Roots ◽

Fine Root ◽

Nutrient Status ◽

Root Turnover ◽

Root Production ◽

Fine Root Production ◽

Fine Root Turnover ◽

Rubber Plantations

SUMMARYUnderstanding the growth dynamics of fine roots and their contribution to soil organic carbon and nutrient pools is crucial for estimating ecosystem carbon and nutrient cycling and how these are influenced by climate change. Rubber is cultivated in more than 10 million hectare globally and the area under rubber cultivation is fast expanding due to socio-economic reasons, apart from the importance given to this species for eco-restoration of degraded lands. An experiment was conducted to quantify fine root production, fine root turnover and carbon and nutrient cycling through fine roots in rubber plantations with different soil nutrient status and rainfall pattern. Fine root production was estimated by sequential coring and ingrowth core methods. Fine root decomposition was determined by the litter bag technique. Carbon and nutrient contents in fine roots were determined and their turnover was computed. Fine root biomass in the top 0–7.5-cm soil layer showed significant seasonal fluctuation and the fluctuations were particularly wide during the transition period from the dry season to the rainy season. Fine root production estimated by the different methods was significantly higher at the lower fertility site and during the higher soil moisture stress year. Fine root turnover ranged from 1.04 to 2.29 year−1. Root carbon and nutrient status showed seasonal variation and lower status was observed during the rainy season. The annual recycling of C, N, P, K, Ca and Mg through fine roots ranged from 590 to 1758, 30 to 85, 3 to 12, 13 to 31, 11 to 35 and 6 to 13 kg ha−1, respectively. Substantial quantities of carbon and nutrients were recycled annually in rubber plantations through fine roots. When soil moisture and nutrient stress were more severe, fine root production, turnover and carbon and nutrient recycling through fine roots were higher.

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Contributions of fine root production and turnover to the carbon and nitrogen cycling in taiga forests of the Alaskan interior

Canadian Journal of Forest Research ◽

10.1139/x26-148 ◽

1996 ◽

Vol 26 (8) ◽

pp. 1326-1336 ◽

Cited By ~ 159

Author(s):

R.W. Ruess ◽

K. Van Cleve ◽

J. Yarie ◽

L.A. Viereck

Keyword(s):

Fine Roots ◽

Fine Root ◽

Organic N ◽

Root Turnover ◽

Root Production ◽

Total Production ◽

Fine Root Production ◽

Litter Fall ◽

Fine Root Turnover ◽

Taiga Forests

Fine root production and turnover were studied in hardwood and coniferous taiga forests using three methods. (1) Using soil cores, fine root production ranged from 1574 ± 76 kg•ha−1•year−1 in the upland white spruce (Piceaglauca (Moench) Voss) stand to 4386 ± 322 kg•ha−1•year−1 in the floodplain balsam poplar (Populusbalsamifera L.) stand, accounting for 49% of total production for coniferous stands and 32% of total production for deciduous stands. Fine root turnover rates were higher in floodplain (0.90 ± 0.06 year−1) stands than in upland (0.42 ± 0.10 year−1) stands. Across all sites, the ratio of fine root turnover to litter fall averaged 2.2 for biomass and 2.8 for N. Both values were higher in floodplain stands than in upland stands, and in coniferous stands than in deciduous stands. (2) The C budget method showed that C allocation to fine roots varied from 150 to 425 g C•m−2•year−1 and suggested that soil respiration was more dependent on C derived from roots than from aboveground inputs. The C allocation ratio (C to roots: C to litter fall) was inversely correlated with litter-fall C and varied from 0.3 to 69.5; there was a tendency for higher proportional belowground allocation in coniferous stands than in deciduous stands and the highest levels were at the earliest successional sites. (3) Estimates of apparent N uptake (Nu), N allocation to fine roots, and fine root production based on N budget calculations showed that annual aboveground N increments exceeded Nu estimates at half the sites, indicating that the method failed to account for large amounts of N acquired by plants. This suggests that plant and (or) mycorrhizal uptake of soil organic N may be more significant to ecosystem N cycling than mineral N turnover by the soil microbial biomass.

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Fine root standing stock and production in young beech and spruce stands

Forestry Journal ◽

10.2478/v10114-011-0023-x ◽

2013 ◽

Vol 59 (3) ◽

Cited By ~ 1

Author(s):

Bohdan Konôpka ◽

Jozef Pajtík ◽

Miriam Maľová

Keyword(s):

Fine Roots ◽

Fine Root ◽

Soil Depth ◽

Standing Stock ◽

Maximum Diameter ◽

Root Turnover ◽

Root Production ◽

Fine Root Production ◽

Turnover Rates ◽

Fine Root Turnover

AbstractFine roots (defined by a maximum diameter of 2 mm) and assimilatory organs are the compartments which rotate carbon much faster than any other tree part. We focused on quantification of fine roots in young European beech and Norway spruce trees growing under the same ecological conditions. Standing stock of fine roots was estimated by soil coring during 2009 - 2012. Fine root production was established by the in-growth bag method. Standing stock and productions of fine roots were comparable in both tree species. The quantity of fine root biomass (at a soil depth of 0 -50 cm) varied inter-annually between 6.08 and 7.41 t per ha in the beech and from 5.10 to 6.49 t per ha in the spruce stand. Annual production of fine roots (soil depth of 0 - 30 cm) was between 1.11 and 1.63 t ha-1 in beech and between 0.95 and 1.54 t.ha-1 in spruce. We found that fine root standing stock at the beginning of each growing season was related to climatic conditions in the previous year. Annual fine root production was influenced by the climatic situation of the current year. In general, a maximum standing stock of fine roots as well as a relatively slow fine root turnover is expected in young forest stands. Whereas production of fine roots prevailed over mortality in a favorable year (sufficiency of precipitations and slightly above-average temperatures in 2010), there was a reverse situation in an unfavorable year (drought episodes in 2011). We concluded that although both forest types represented contrasting turnovers of assimilatory organs (once a year and once in 5 years in beech and spruce respectively), fine root turnover rates were very similar (approx. once per four years).

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Growth, decay, and turnover rates of fine roots of basket willows

Canadian Journal of Forest Research ◽

10.1139/x98-063 ◽

1998 ◽

Vol 28 (6) ◽

pp. 893-902 ◽

Cited By ~ 24

Author(s):

Rose-Marie Rytter ◽

Lars Rytter

Keyword(s):

Soil Temperature ◽

Fine Roots ◽

Fine Root ◽

Clay Soil ◽

Turnover Time ◽

Root Turnover ◽

Turnover Rates ◽

Fine Root Turnover ◽

Morphological Studies ◽

Significant Difference

The aim of the present study was to calculate fine-root turnover rates in stands of basket willow (Salix viminalis L.). Fine-root number was recorded in minirhizotrons in two adjacent short-rotation forest stands. Stand A was a regularly spaced plantation on clay soil. Stand B contained lysimeters, which were inserted in the soil and filled with either clay soil or washed sand. Both stands were irrigated and fertilized daily, to provide near-optimum conditions with respect to water and nutrient availability. The calculations were based on morphological studies and observations in minirhizotrons. Mean fine-root ages of growth and decay phases were calculated from third-order polynomials, and by summing up those phases and adding a short stationary phase, turnover time was obtained. Calculated fine-root turnover rates were 4.95.8 year1 in the plantation and 4.88.1 year1 in the lysimeters. No significant difference in turnover rates was detected between clay and sand substrates. Soil temperature had a significant effect on the decay phase, and in the calculations the data were weighted by soil temperature intervals. The importance of observing fine roots throughout the year is stressed.

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Fine-root turnover patterns and their relationship to root diameter and soil depth in a14C-labeled hardwood forest

New Phytologist ◽

10.1111/j.1469-8137.2006.01847.x ◽

2006 ◽

Vol 172 (3) ◽

pp. 523-535 ◽

Cited By ~ 140

Author(s):

J. D. Joslin ◽

J. B. Gaudinski ◽

M. S. Torn ◽

W. J. Riley ◽

P. J. Hanson

Keyword(s):

Fine Root ◽

Soil Depth ◽

Root Diameter ◽

Hardwood Forest ◽

Root Turnover ◽

Fine Root Turnover

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The effect of limited availability of N or water on C allocation to fine roots and annual fine root turnover in Alnus incana and Salix viminalis

Tree Physiology ◽

10.1093/treephys/tpt060 ◽

2013 ◽

Vol 33 (9) ◽

pp. 924-939 ◽

Cited By ~ 23

Author(s):

R.-M. Rytter

Keyword(s):

Fine Roots ◽

Fine Root ◽

Salix Viminalis ◽

Root Turnover ◽

Alnus Incana ◽

Fine Root Turnover ◽

Limited Availability

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Fine root turnover in a northern hardwood forest: a direct comparison of the radiocarbon and minirhizotron methods

Canadian Journal of Forest Research ◽

10.1139/x02-123 ◽

2002 ◽

Vol 32 (9) ◽

pp. 1692-1697 ◽

Cited By ~ 93

Author(s):

Geraldine L Tierney ◽

Timothy J Fahey

Keyword(s):

Fine Roots ◽

Fine Root ◽

Age Distribution ◽

Hardwood Forest ◽

Root Turnover ◽

Northern Hardwood Forest ◽

Fine Root Turnover ◽

Northern Hardwood ◽

Root Age ◽

Long Term Observation

We examined fine root turnover using both the minirhizotron and radiocarbon methods within the organic horizon of a northern hardwood forest to better understand discrepancies in turnover estimates obtained using these methods. The recently developed radiocarbon method estimates the mean age of organic matter by comparing its radiocarbon content to recorded atmospheric radiocarbon levels, which peaked in the 1960s as a result of thermonuclear weapons testing. The radiocarbon content of fine roots harvested from minirhizotron tubes did not differ from that of roots collected from the soil, suggesting these two methods sampled the same population of fine roots. However, long-term observation of fine root survivorship using minirhizotrons showed that root age distribution is positively skewed, causing systematic overestimation of fine root turnover by the minirhizotron method and underestimation by the radiocarbon method. We developed a parametric regression model of fine root survivorship. Our estimate of fine root turnover (about 30% per year) using this variation of the minirhizotron method was supported by radiocarbon data considered in conjunction with fine root age distribution.

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Influence of Pruning and Irrigation on Root Longevity of `Concord' Vines

HortScience ◽

10.21273/hortsci.33.3.511a ◽

1998 ◽

Vol 33 (3) ◽

pp. 511a-511

Author(s):

L.H. Comas ◽

D.M. Eissenstat ◽

A.N. Lakso ◽

R. Dunst

Keyword(s):

Fine Roots ◽

Fine Root ◽

Cultural Practices ◽

Growing Season ◽

Root Production ◽

Root Dynamics ◽

Supplemental Irrigation ◽

Root Longevity ◽

Root Lifespan ◽

Median Lifespan

Improved cultural practices in grape require a better understanding of root growth and physiology. Seasonal root dynamics were examined in mature `Concord' vines with balanced or minimal-pruning, and with or without supplemental irrigation in Fredonia, N.Y. Fine roots were continuously produced during the growing season starting in mid-June around time of bloom. Roots began to die in September at verasion. Minimal-pruned vines produced more roots than balanced-pruned vines, with the minimal-pruned/unirrigated vines producing the most roots. Irrigation and pruning delayed fine root production at the beginning of the growing season. Peak fine root flush was 16 June to 21 July 1997 for the minimal-pruned/unirrigated treatment, while peak flush was 7 July to 2 Sept. 1997 for balanced-pruned/irrigated treatment. In minimal-pruned vines, many roots were observed down to depths of 120 cm. In contrast, balanced-pruned vines had very few fine roots deeper than 40 cm. From initial observations, median lifespan of fine roots was 5 to 9.5 weeks, depending on treatment and depth in soil. Fine roots lived longer in the top 15-cm than in the 16- to 30-cm layer of soil in all treatments. Both minimal pruning and irrigation increased root lifespan. Fine roots had the shortest lifespan in the balanced-pruned/unirrigated treatment and the longest lifespan in the minimal-pruned/irrigated treatment.

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