Effects of Low Water Availability on Root Placement and Shoot Development in Landraces and Modern Barley Cultivars

Early vigor has been proposed as a favorable trait for cereals grown in drought-prone environments. This research aimed at characterizing early stage shoot and root growth of three Spanish barley landraces compared with three modern cultivars. Genotypes were grown in an automated phenotyping platform, GrowScreen-Rhizo, under well-watered and drought conditions. Seminal and lateral root length, root system width and depth were recorded automatically during the experiment. Drought induced greater growth reduction in shoots (43% dry weight reduction) than in roots (23% dry weight). Genotypic differences were larger under no stress, partly due to a more profuse growth of landraces in this treatment. Accession SBCC146 was the most vigorous for shoot growth, whereas SBCC073 diverted more assimilates to root growth. Among cultivars, Cierzo was the most vigorous one and Scarlett had the least root dry weight of all genotypes, under both conditions. Root growth was redirected to lateral roots when seminal roots could not progress further in dry soil. This study reveals the presence of genetic diversity in dynamics of early growth of barley. The different patterns of growth observed for SBCC073 and SBCC146 should be explored further, to test if they affect field performance of barley in drought-prone environments.

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Overexpression of OsPIN2 Regulates Root Growth and Formation in Response to Phosphate Deficiency in Rice

International Journal of Molecular Sciences ◽

10.3390/ijms20205144 ◽

2019 ◽

Vol 20 (20) ◽

pp. 5144

Author(s):

Huwei Sun ◽

Xiaoli Guo ◽

Fugui Xu ◽

Daxia Wu ◽

Xuhong Zhang ◽

...

Keyword(s):

Root Growth ◽

Growth And Development ◽

Plant Root ◽

Lateral Roots ◽

Root Hairs ◽

Phosphate Deficiency ◽

P Deficiency ◽

Auxin Distribution ◽

Seminal Roots ◽

Underlying Mechanisms

The response of root architecture to phosphate (P) deficiency is critical in plant growth and development. Auxin is a key regulator of plant root growth in response to P deficiency, but the underlying mechanisms are unclear. In this study, phenotypic and genetic analyses were undertaken to explore the role of OsPIN2, an auxin efflux transporter, in regulating the growth and development of rice roots under normal nutrition condition (control) and low-phosphate condition (LP). Higher expression of OsPIN2 was observed in rice plants under LP compared to the control. Meanwhile, the auxin levels of roots were increased under LP relative to control condition in wild-type (WT) plants. Compared to WT plants, two overexpression (OE) lines had higher auxin levels in the roots under control and LP. LP led to increased seminal roots (SRs) length and the root hairs (RHs) density, but decreased lateral roots (LRs) density in WT plants. However, overexpression of OsPIN2 caused a loss of sensitivity in the root response to P deficiency. The OE lines had a shorter SR length, lower LR density, and greater RH density than WT plants under control. However, the LR and RH densities in the OE lines were similar to those in WT plants under LP. Compared to WT plants, overexpression of OsPIN2 had a shorter root length through decreased root cell elongation under control and LP. Surprisingly, overexpression of OsPIN2 might increase auxin distribution in epidermis of root, resulting in greater RH formation but less LR development in OE plants than in WT plants in the control condition but levels similar of these under LP. These results suggest that higher OsPIN2 expression regulates rice root growth and development maybe by changing auxin distribution in roots under LP condition.

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Longleaf Pine Root System Development and Seedling Quality in Response to Copper Root Pruning and Cavity Size

Southern Journal of Applied Forestry ◽

10.1093/sjaf/35.1.5 ◽

2011 ◽

Vol 35 (1) ◽

pp. 5-11 ◽

Cited By ~ 8

Author(s):

Mary Anne Sword Sayer ◽

Shi-Jean Susana Sung ◽

James D. Haywood

Keyword(s):

Root Growth ◽

Root System ◽

System Development ◽

Longleaf Pine ◽

Lateral Roots ◽

Dry Weight ◽

Root Pruning ◽

Cavity Size ◽

Root System Development ◽

Primary Lateral

Abstract Cultural practices that modify root system structure in the plug of container-grown seedlings have the potential to improve root system function after planting. Our objective was to assess how copper root pruning affects the quality and root system development of longleaf pine seedlings grown in three cavity sizes in a greenhouse. Copper root pruning increased seedling size, the allocation of root system dry weight to the taproot, and the fraction of fibrous root mass allocated to secondary lateral roots compared with primary lateral roots. It decreased the allocation of root system dry weight to primary lateral roots and led to a distribution of root growth potential that more closely resembled the root growth of naturally sown seedlings. These effects of copper root pruning may benefit longleaf pine establishment. However, because copper root pruning increased competition for cavity growing space among the taproot and fibrous roots, we suggest that recommendations regarding cavity size and seedling quality parameters be tailored for copper-coated cavities.

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Survival and growth of four amabilis fir stock types on Vancouver Island

The Forestry Chronicle ◽

10.5558/tfc67147-2 ◽

1991 ◽

Vol 67 (2) ◽

pp. 147-154 ◽

Cited By ~ 2

Author(s):

F. T. Pendl ◽

B. N. D'Anjou

Keyword(s):

Root Growth ◽

Lateral Roots ◽

Survival Rates ◽

Field Performance ◽

Vancouver Island ◽

Growth Capacity ◽

Root Growth Capacity ◽

Stock Type ◽

Stock Types ◽

Initial Root

Four stock types of amabilis fir (Abies amabilis) planted on Vancouver Island were compared for root growth capacity and field performance. Initial root growth capacity ratings and field performance of the stock types after five years differed significantly. Ranking the stock types by decreasing survival, stem height and diameter: 1 + 1 PBR 211 (89.4%, 78 cm, 15.7 mm), 1 + 0 PSB 313 (79.7%, 73 cm, 13.8 mm), 1 + 0 PSB 211 (76.8%, 66 cm, 12.9 mm) and 2 + 0 BR (58.9%, 59 cm, 11.0 mm). Given current nursery and planting costs and survival rates, the 1 + 0 PSB 313 and 211 are least expensive reforestation options, the 2 + 0 BR and 1 + 1 PBR 211 the most expensive. Root form of samples of each stock type lack well developed tap and lateral roots with root spiralling evident in the styroblock stock. Key words: Amabilis fir, stock types, bareroot, styroblock plugs

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Aluminum in corn plants: influence on growth and morpho-anatomy of root and leaf

Revista Brasileira de Ciência do Solo ◽

10.1590/s0100-06832013000100018 ◽

2013 ◽

Vol 37 (1) ◽

pp. 177-187 ◽

Cited By ~ 8

Author(s):

Michelli Fernandes Batista ◽

Ismar Sebastião Moscheta ◽

Carlos Moacir Bonato ◽

Marcelo Augusto Batista ◽

Odair José Garcia de Almeida ◽

...

Keyword(s):

Zea Mays ◽

Root Growth ◽

Plant Height ◽

Dry Matter ◽

Zea Mays L ◽

Lateral Roots ◽

Dry Weight ◽

Al Toxicity ◽

Limiting Factors ◽

Corn Plants

Aluminum (Al) toxicity is one of the most limiting factors for productivity. This research was carried out to assess the influence of Al nutrient solution on plant height, dry weight and morphoanatomical alterations in corn (Zea mays L.) roots and leaves. The experiment was conducted in a greenhouse with five treatments consisting of Al doses (0, 25, 75, 150, and 300 µmol L-1) and six replications. The solutions were constantly aerated, and the pH was initially adjusted to 4.3. The shoot dry matter, root dry matter and plant height decreased significantly with increasing Al concentrations. Compared to the control plants, it was observed that the root growth of corn plants in Al solutions was inhibited, there were fewer lateral roots and the development of the root system reduced. The leaf anatomy of plants grown in solutions containing 75 and 300 µmol L-1 Al differed in few aspects from the control plants. The leaf sheaths of the plants exposed to Al had a uniseriate epidermis coated with a thin cuticle layer, and the cells of both the epidermis and the cortex were less developed. In the vascular bundle, the metaxylem and protoxylem had no secondary walls, and the diameter of both was much smaller than of the control plants.

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Conserved LBL1-ta-siRNA and miR165/166-RLD1/2 modules regulate root development in maize

Development ◽

10.1242/dev.190033 ◽

2020 ◽

Vol 148 (1) ◽

pp. dev190033

Author(s):

Vibhav Gautam ◽

Archita Singh ◽

Sandeep Yadav ◽

Sharmila Singh ◽

Pramod Kumar ◽

...

Keyword(s):

Root Growth ◽

Root Development ◽

Lateral Roots ◽

Root System Architecture ◽

Maize Root ◽

Altered Expression ◽

Auxin Distribution ◽

Seminal Roots ◽

Crown Roots

ABSTRACTRoot system architecture and anatomy of monocotyledonous maize is significantly different from dicotyledonous model Arabidopsis. The molecular role of non-coding RNA (ncRNA) is poorly understood in maize root development. Here, we address the role of LEAFBLADELESS1 (LBL1), a component of maize trans-acting short-interfering RNA (ta-siRNA), in maize root development. We report that root growth, anatomical patterning, and the number of lateral roots (LRs), monocot-specific crown roots (CRs) and seminal roots (SRs) are significantly affected in lbl1-rgd1 mutant, which is defective in production of ta-siRNA, including tasiR-ARF that targets AUXIN RESPONSE FACTOR3 (ARF3) in maize. Altered accumulation and distribution of auxin, due to differential expression of auxin biosynthesis and transporter genes, created an imbalance in auxin signalling. Altered expression of microRNA165/166 (miR165/166) and its targets, ROLLED1 and ROLLED2 (RLD1/2), contributed to the changes in lbl1-rgd1 root growth and vascular patterning, as was evident by the altered root phenotype of Rld1-O semi-dominant mutant. Thus, LBL1/ta-siRNA module regulates root development, possibly by affecting auxin distribution and signalling, in crosstalk with miR165/166-RLD1/2 module. We further show that ZmLBL1 and its Arabidopsis homologue AtSGS3 proteins are functionally conserved.

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The effect of wrenching on morphology and field performance of Douglas fir and loblolly pine seedlings

Canadian Journal of Forest Research ◽

10.1139/x76-061 ◽

1976 ◽

Vol 6 (4) ◽

pp. 453-458 ◽

Cited By ~ 20

Author(s):

Yasuomi Tanaka ◽

J. D. Walstad ◽

J. E. Borrecco

Keyword(s):

Loblolly Pine ◽

Lateral Roots ◽

Field Performance ◽

Dry Weight ◽

Douglas Fir ◽

Shoot Dry Weight ◽

Percentage Points ◽

Pine Seedlings ◽

Nursery Stock ◽

Second Year

Second-year Douglas fir and 1st-year loblolly pine nursery stock were undercut and wrenched while actively growing in nursery beds. Their morphology and field performance were compared with Douglas fir seedlings that had been undercut only and with loblolly pine seedlings that had been left intact.The treatment produced shorter, thinner-stemmed loblolly pine seedlings with reduced shoot dry weight. Height, diameter, and shoot dry weight of Douglas fir seedlings were virtually unaffected, but root dry weight was increased substantially. Development of fibrous lateral roots was stimulated in both species. As a consequence, shoot–root ratios were considerably improved, and the seedlings were better conditioned to withstand outplanting. On droughty sites, field survival of Douglas fir was increased by 20 percentage points and loblolly pine by 30 percentage points. Wrenching also extended by several weeks the fall and spring planting periods for loblolly pine and the fall planting period for Douglas fir.

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The allelopathic potential of phenolic acids associated with the rhizosphere of Pteridium aquilinum

Canadian Journal of Botany ◽

10.1139/b76-259 ◽

1976 ◽

Vol 54 (21) ◽

pp. 2440-2444 ◽

Cited By ~ 46

Author(s):

Anthony D. M. Glass

Keyword(s):

Root Growth ◽

Phenolic Acids ◽

Phenolic Acid ◽

Dry Weight ◽

Pteridium Aquilinum ◽

Fresh Weight ◽

Root Volume ◽

Allelopathic Potential ◽

Lateral Root Development ◽

Seminal Roots

Barley plants were grown hydroponically in solutions which exactly reproduced the major phenolic acid composition of the soil associated with Pteridium aquilinum (L.) Kuhn. In CaSO4 solution these compounds severely inhibited root growth as measured by fresh weight, dry weight, and root volume analyses. The form of root growth was also modified by the presence of the phenolic acids in that by 3 weeks extensive lateral root development had occurred, whereas only limited elongation of seminal roots occurred. Inhibition, as measured by fresh weight determinations, was most pronounced when roots were grown at 5 and 30 °C and least pronounced between 15 and 20 °C. Other species examined, with the sole exception of Agropyron repens (L.)Beauv., showed similar responses to the presence of the phenolic acids. Microscopic examination of the tips of barley roots treated with phenolic acid revealed that meristematic cells were prematurely vacuolated.In constrast with the striking effects of these phenolics on root growth in CaSO4 solution, there were no obvious effects on barley root growth when the phenolic acids were dissolved in a complete inorganic nutrient medium.

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Moderate sodium has positive effects on shoots but not roots of salt-tolerant barley grown in a potassium-deficient sandy soil

Crop and Pasture Science ◽

10.1071/cp11162 ◽

2011 ◽

Vol 62 (11) ◽

pp. 972 ◽

Cited By ~ 9

Author(s):

Qifu Ma ◽

Richard Bell ◽

Ross Brennan

Keyword(s):

Root Growth ◽

Shoot Growth ◽

Dry Weight ◽

Triticum Aestivum L ◽

Salt Tolerant ◽

Hordeum Vulgare L ◽

Barley Cultivars ◽

Positive Effects ◽

Shoot Dry Weight ◽

K Deficiency

In the agricultural lands of south-western Australia, salinity severely affects about 1 million hectares, and there is also widespread occurrence of potassium (K) deficiency. This study investigated whether the effects of sodium (Na) on crop K nutrition vary with plant salt sensitivity. In a glasshouse experiment with loamy sand, two barley cultivars (Hordeum vulgare L. cv. Gairdner, salt sensitive, and cv. CM72, salt tolerant) and one wheat cultivar (Triticum aestivum L. cv. Wyalkatchem, salt tolerant) were first grown in soil containing 30 mg extractable K/kg for 4 weeks to create mildly K-deficient plants, then subjected to Na (as NaCl) and additional K treatments for 3 weeks. Although high Na (300 mg Na/kg) reduced leaf numbers, moderate Na (100 mg Na/kg) hastened leaf development in barley cultivars but not in wheat. In the salt-tolerant CM72, moderate Na also increased tiller numbers, shoot dry weight and Na accumulation, but not root growth. The positive effect of moderate Na on shoot growth in CM72 was similar to that of adding 45 mg K/kg. Root growth relative to shoot growth was enhanced by adequate K supply (75 mg K/kg) compared with K deficiency, but not by Na supply. Soil Na greatly reduced the K/Na and Ca/Na ratios in shoots and roots, while additional K supply increased the K/Na ratio with little effect on the Ca/Na ratio. The study showed that the substitution of K by Na in barley and wheat was influenced not only by plant K status, but by the potential for Na uptake in roots and Na accumulation in shoots, which may play a major role in salt tolerance. The increased growth in shoots but not roots of salt-tolerant CM72 in response to moderate Na and the greater adverse effect of soil K deficiency on roots than shoots in all genotypes would make the low-K plants more vulnerable to saline and water-limited environments.

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Genotypic variability of root and shoot traits of bread wheat (Triticum aestivum L.) at seedling stage

Genetika ◽

10.2298/gensr2102687b ◽

2021 ◽

Vol 53 (2) ◽

pp. 687-702

Author(s):

Milica Blazic ◽

Dejan Dodig ◽

Vesna Kandic ◽

Dragoslav Djokic ◽

Tomislav Zivanovic

Keyword(s):

Bread Wheat ◽

Root Length ◽

Lateral Roots ◽

Primary Root ◽

Dry Weight ◽

Triticum Aestivum L ◽

Stem Length ◽

Total Length ◽

Seminal Roots ◽

Primary Root Length

The evaluation of the embryonic root and stem of bread wheat (Triticum aestivum L.) in the early stage of development (seedling stage) can be a powerful tool in wheat breeding aimed at obtaining progenies with a greater early vigour. It is revealed that genotypes with faster early vigour have produced higher biomass and grain yield. In this study, the evaluation of traits of the embryonic root and the embryonic stem of 101 bread wheat genotypes was preformed at the 10-day old seedlings. The following eight morphological traits of roots and stems were analysed: primary root length, branching interval, the number of roots, total length of lateral roots, angle of seminal roots, stem length, root dry weight and the stem dry weight. Analysed lateral roots included seminal roots. The greatest, i.e. the smallest variability of observed traits was detected in the branching interval, i.e. the stem length, respectively. The highest positive correlation was determined between the primary root length and the total length of lateral roots. The cluster analysis, based on observed traits, shows that genotypes were clearly divided into two main clusters, A and B. The two clusters essentially differed from each other in the values of the following traits: primary root length, total length of lateral roots, root dry weight, stem dry weight and the stem length. Genotypes with shorter primary and lateral roots, lower root and stem dry weight and a shorter stem were grouped in the cluster B. On the other hand, the cluster A encompassed genotypes with values of these traits above or around the average. The values of the remaining analysed traits: the angle of seminal roots, the number of lateral roots and the branching interval varied greatly between obtained clusters. The cluster analysis showed the homogeneity of genotypes originating from Serbia and the region; their values of the root and stem length and weight were mostly around and below the average. However, the values of the angle of seminal roots, number of lateral roots and the branching interval were above average.

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Phosphorus restriction: control of transplant growth

Canadian Journal of Plant Science ◽

10.4141/p99-120 ◽

2000 ◽

Vol 80 (4) ◽

pp. 875-877 ◽

Cited By ~ 1

Author(s):

A. Liptay ◽

P. Sikkema

Keyword(s):

Root Growth ◽

Nutrient Solution ◽

Seedling Growth ◽

Leaf Growth ◽

Field Performance ◽

Dry Weight ◽

Differential Growth ◽

Reduced Height ◽

Complete Nutrient Solution ◽

Leaf Dry Weight

Control of tomato (Lycopersicon esculentum Mill.) seedling growth and height during production in the greenhouse is critical for efficient subsequent transplanting and acceptable field performance. Height can be reduced by P fertilisation. Eliminating P from nutrient solutions severely restricted growth. When fed a 10 mg P L−1 in the nutrient solution, seedlings were 11 cm tall after 49 d of growth, but only 3 cm tall without P. Intermediate P reduced height within this range. Transplanting was simulated after 49 d of seedling production by transferring the transplants to a temperature-controlled root chamber in larger volume cells plus fertilisation with a complete nutrient solution. Transplant growth with a complete nutrient solution caused differential growth according to the prior P feeding regime. New root growth in the various treatments was dependent on root growth during the transplant stage. However, shoot growth differed greatly among the P levels. Seedlings grown without any P during transplant production grew very slowly with only a 25% increase in leaf growth after 9 d. With the 2 mg L−1 feeding during transplant production of leaf dry weight increased over 200% during the 9-d period. In conclusion, seedling growth restriction can be achieved by P deprivation; the amount of P deprivation, however, affects subsequent seedling growth. Key words: Phosphorus, nutrients, tomato, transplant.

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