Root apical diameter and root elongation rate of rubber seedlings<i>(Hevea brasiliensis)</i>show parallel responses to photoassimilate availability

Thaler, Philippe; Pagès, Loïc

doi:10.1034/j.1399-3054.1996.970222.x

Cited by 82 publications

(71 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Recovery of the leaf area index occurs rapidly at the beginning of the rainy season in Eucalyptus stands in this region (Nouvellon, unpublished data). A competition for photosynthate explained asynchronous growth rates between secondary root and leaves of Hevea brasiliensis seedlings (Thaler and Pagès, 1996). The difference in growth between roots and leaves was enhanced in shaded plants.…”

Section: Discussionmentioning

confidence: 94%

Root elongation in tropical Eucalyptus plantations: effect of soil water content

et al. 2008

View full text Add to dashboard Cite

-• Sustainability of Eucalyptus plantations is often questioned in resource-limited environments, especially in areas characterized by soils with poor nutrient and water holding capacities. Yet, field-based observations of fine root dynamics in relation with the seasonality of rainfall are lacking.• This study was undertaken on two Eucalyptus stands planted in the Kouilou Region (south-western Congo), which is characterized by a four-monthlong dry season. Fine root (less than 2 mm in diameter) dynamics were studied using rhizotron observations of root elongation in the field.• Fine root elongation rates displayed a seasonal variation in the two stands, with higher elongation rates during the rainy season than during the dry season. Positive and significant correlations were found between fine root elongation rates and soil water content at all depths, but a better correlation was found with soil water content in the deep soil horizon than in the superficial horizons.• These results suggest that the temporal variations in fine root elongation were related to the seasonality of rainfall, and they were probably associated with seasonal changes in tree water status, carbon assimilation and belowground allocation. fine roots / growth / rhizotron / Eucalyptus / soil water content Résumé -Élongation des racines dans les plantations tropicales d'Eucalyptus : effet du contenu en eau du sol.• La question de la durabilité des plantations d'Eucalyptus est souvent posée dans les environnements où les ressources sont limitées, en particulier les zones où les sols ont une faible capacité à retenir l'eau et les nutriments et où la saison sèche est longue. Pourtant, les observations in situ de la dynamique racinaire en relation avec la saisonnalité des pluies sont inexistantes.• Cette étude a été réalisée dans deux plantations d'Eucalyptus de la région du Kouilou dans le sud ouest du Congo, qui est caractérisée par quatre mois de saison sèche. La dynamique des racines fines (moins de 2 mm de diamètre) a été étudiée à l'aide de rhizotrons permettant d'observer l'élongation racinaire au champ.• La vitesse d'élongation des racines fines montrait une variation saisonnière dans les deux plantations, avec des vitesses plus élevées en saison des pluies qu'en saison sèche. Des corrélations positives et significatives ont été trouvées entre la vitesse d'élongation des racines fines et la teneur en eau du sol à toutes les profondeurs, mais les meilleures corrélations ont été observées avec la teneur en eau des horizons profonds.• Cela suggère que les variations temporelles de l'élongation des racines fines sont reliées à la saisonnalité des précipitations, et qu'elles sont associées aux changements saisonniers d'état hydrique des arbres, d'assimilation carbonée et d'allocation vers les parties souterraines. racines fines / croissance / rhizotron / Eucalyptus / teneur en eau du sol

show abstract

Section: Discussionmentioning

confidence: 94%

Root elongation in tropical Eucalyptus plantations: effect of soil water content

et al. 2008

View full text Add to dashboard Cite

show abstract

“…When wheat or barley roots were subjected to a localized treatment with NO 3 − , the lateral roots growing in the NO 3 − -rich zone were significantly thicker than those not exposed to NO 3 − (Drew et al, 1973;Hackett, 1972). It has been noted that there is a positive correlation between root diameter and root elongation rate (Cahn et al, 1989;Thaler and Pages, 1996), so that the changes in root diameter observed in the NO 3 − -rich zone could be causally linked to the localized stimulation of lateral root elongation. There may be other regulatory mechanisms affecting the specific root length independently of growth rate, and perhaps these could operate systemically.…”

Section: Root Diametermentioning

confidence: 99%

The nutritional control of root development

Forde

Lorenzo

2002

Interactions in the Root Environment: An Integrated Approach

221

254

View full text Add to dashboard Cite

Root development is remarkably sensitive to variations in the supply and distribution of inorganic nutrients in the soil. Here we review examples of the ways in which nutrients such as N, P, K and Fe can affect developmental processes such as root branching, root hair production, root diameter, root growth angle, nodulation and proteoid root formation. The nutrient supply can affect root development either directly, as a result of changes in the external concentration of the nutrient, or indirectly through changes in the internal nutrient status of the plant. The direct pathway results in developmental responses that are localized to the part of the root exposed to the nutrient supply; the indirect pathway produces systemic responses and seems to depend on long-distance signals arising in the shoot. We propose the term 'trophomorphogenesis' to describe the changes in plant morphology that arise from variations in the availability or distribution of nutrients in the environment. We discuss what is currently known about the mechanisms of external and internal nutrient sensing, the possible nature of the long-distance signals and the role of hormones in the trophomorphogenic response.Abbreviations: ABA, abscisic acid; NR, nitrate reductase; P i , inorganic phosphate

show abstract

“…This relationship could be due to an increased carbon supply to nodules under drought stress from the stored carbohydrates in thicker roots. Large root diameter is known to correlate with greater sink strength (Thaler and Pages 1996). Previous evaluations with BAT 477, showed that this line maintained a relatively higher level of SNF under drought stress; possibly due to a deep and vigorous root system that accessed water from deeper soil layers to avoid drought and to alleviate stress on SNF process (Castellanos et al 1996;Araújo et al 2015).…”

Section: Relationship Between Root Vigor and Shoot Traits Including Gmentioning

confidence: 99%

“…A key approach is breeding of bean varieties resistant to drought to ensure food security in marginal areas. Defining the root and shoot level physiological mechanisms in response to drought helps to identify desirable traits and procedures for phenotyping populations and accelerating plant breeding for better yield under water shortage (Oosterom et al 2016). Several shoot and root traits improve resistance to drought (Araújo et al 2015).…”

mentioning

confidence: 99%

Root traits and their potential links to plant ideotypes to improve drought resistance in common bean

Polanía

Poschenrieder

Rao

et al. 2017

Theor. Exp. Plant Physiol.

View full text Add to dashboard Cite

Drought stress limits growth and yield of crops, particularly under smallholder production systems with minimal use of inputs and edaphic limitations such as nitrogen (N) deficiency. The development of genotypes adapted to these conditions through genetic improvement is an important strategy to address this limitation. The identification of morpho-physiological traits associated with drought resistance contributes to increasing the efficiency of breeding programs. A set of 36 bean genotypes belonging to the Middle American gene pool was evaluated. A greenhouse study using soil cylinders was conducted to determine root vigor traits (total root length and fine root production) under drought stress.Two field trials were conducted to determinate grain yield, symbiotic nitrogen fixation (SNF) ability and other shoot traits under drought stress. Field data on grain yield and other shoot traits measured under drought were related with the greenhouse data on root traits under drought conditions to test the relationships between shoot traits and root traits. Response of root vigor to drought stress appeared to be related with ideotypes of water use (water savers and water spenders). The water spender ideotypes presented deeper root system, while the water saver ideotypes showed a relatively shallower root system. Increase in SNF ability under drought stress was associated with greater values of mean root diameter while greater acquisition of N from soil was associated with finer root system. We identified seven common bean lines (SEA 15, NCB 280, SCR 16, SMC 141, BFS 29, BFS 67 and SER 119) that showed greater root vigor under drought stress in the greenhouse and higher values of grain yield under drought stress in the field. These lines could serve as parents for improving drought resistance in common bean.

show abstract

Root apical diameter and root elongation rate of rubber seedlings(Hevea brasiliensis)show parallel responses to photoassimilate availability

Cited by 82 publications

References 22 publications

Root elongation in tropical Eucalyptus plantations: effect of soil water content

Root elongation in tropical Eucalyptus plantations: effect of soil water content

The nutritional control of root development

Root traits and their potential links to plant ideotypes to improve drought resistance in common bean

Contact Info

Product

Resources

About