scholarly journals Recurrent Selection for Rubber Yield in Russian Dandelion

2017 ◽  
Vol 142 (6) ◽  
pp. 470-475 ◽  
Author(s):  
Katrina J.M. Hodgson-Kratky ◽  
Olivier M. Stoffyn ◽  
David J. Wolyn
Keyword(s):  
Error Control ◽  
Recurrent Selection ◽  
Rubber Tree ◽  
Dry Weight ◽  
Root Weight ◽  
Promising Alternative ◽  
Root Dry Weight ◽  
Loam Soil ◽  
Selection For ◽  
New Crop

Russian dandelion [Taraxacum kok-saghyz (TKS)] is a promising alternative to the Para rubber tree (Hevea brasiliensis) as a source of natural rubber; however, rubber yields must be improved for this undomesticated species to become a profitable new crop. Half-sib family recurrent selection was conducted for four cycles to increase rubber yield, estimated as the product of rubber percentage, and root dry weight per plant. Two distinct populations were developed for adaptation to sand and loam soil types. Rubber percentage increased from 4.17% for the cycle 0 (C0) population to 6.40% for the C4-loam population. Rubber yield also increased from 0.15 to 0.22 g/plant after four selection cycles. Although phenotypic variation was observed, selection had no effect on root weight; all populations averaged 3.70 g/plant. Rubber yield and percentage and root dry weight were not increased after four selection cycles on sandy soils, likely because of poor adaptation and high environmental variation. Year and soil type affected rubber yields; however, rubber percentage was more stable than root dry weight. Overall, russian dandelion can be improved for rubber yield, and further studies with increased error control should be considered to enhance root dry weight.

Eight cycles of half-sib family recurrent selection to improve rubber yield in russian dandelion

2021 ◽  
Author(s):  
David Wolyn ◽  
Gregory Innes
Keyword(s):  
Natural Rubber ◽  
Phenotypic Variation ◽  
Hevea Brasiliensis ◽  
Recurrent Selection ◽  
Rubber Tree ◽  
Dry Weight ◽  
Selection Response ◽  
Root Dry Weight ◽  
Selection For

Russian dandelion (Taraxacum kok-saghyz) produces natural rubber which can complement the world’s supply of this strategic commodity, derived mainly from the Para rubber tree (Hevea brasiliensis). Four cycles of half-sib family recurrent selection conducted previously in russian dandelion improved rubber yield nearly 50%. The objectives of this research were to continue selection for four additional cycles and evaluate progress from eight generations of breeding, and assess the potential for future gains. Rubber yield increased from 0.205 to 0.378 g/plant from Cycle 0 (C0) to C8, representing an 84% improvement, or 10% per cycle. Increases from C0 to C4 were similar to those from C4 to C8. Root dry weight did not increase from selection and improved yield only resulted from enhancing rubber percentage which changed from 4.35 to 7.62%. Selection response has not plateaued and phenotypic variation has not decreased, indicating continued gains can occur with additional breeding.

scholarly journals Needle-Clipping Longleaf Pine and Top-Pruning Loblolly Pine in Bareroot Nurseries

1998 ◽  
Vol 22 (4) ◽  
pp. 235-240 ◽  
Author(s):  
David B. South
Keyword(s):  
Loblolly Pine ◽  
Seedling Survival ◽  
Longleaf Pine ◽  
Weight Ratio ◽  
Dry Weight ◽  
Root Weight ◽  
Root Weight Ratio ◽  
Root Dry Weight ◽  
Percentage Points ◽  
Average Survival

Abstract Studies have shown that clipping needles of longleaf pine before outplanting can increase average seedling survival by 13 percentage points. Under some situations, the increase in survival might be due to a reduction in transpiration. For loblolly pine, top-pruning in the nursery might increase average survival by 6 percentage points. Benefits of pruning appear greater when seedlings experience stress after planting and when nonpruned seedlings have low root weight ratios (root dry weight/total seedling dry weight). On some droughty sites, a seedling with a 0.3 root weight ratio might have an 80% chance of survival, while a seedling with a 0.2 root weight ratio might only have a 53% chance of survival. In most studies where heights were measured after 3 yr in the field, pruned seedlings were the same height as nonpruned seedlings (± 7 cm). South. J. Appl. For. 22(4):235-240.

scholarly journals Increasing Cell Size and Reducing Medium Compression Enhance Lettuce Transplant Quality and Field Production

HortScience ◽  
1996 ◽  
Vol 31 (2) ◽  
pp. 184-189 ◽  
Author(s):  
Silvana Nicola ◽  
Daniel J. Cantliffe
Keyword(s):  
Cell Size ◽  
Sandy Soil ◽  
Shoot Growth ◽  
Weight Ratio ◽  
Dry Weight ◽  
Root Weight ◽  
Growth Ratio ◽  
Root Dry Weight ◽  
Total Dry Weight ◽  
Initial Root

`South Bay' lettuce (Lactuca sativa L.) seedlings were grown in a greenhouse during winter, spring, and fall to investigate the effect of cell size and medium compression on transplant quality and yield. Four Speedling planter flats (1.9-, 10.9-, 19.3-, 39.7-cm3 cells) and two medium compression levels [noncompressed and compressed (1.5 times in weight)] were tested. The two larger cell sizes and compression of the medium led to increased plant shoot growth. Conversely, root weight ratio [RWR = (final root dry weight ÷ final total dry weight + initial root dry weight ÷ initial total dry weight) ÷ 2] was highest with the smaller cells without medium compression. Lettuce transplants were field-grown on sand and muck soils. The larger cells delayed harvest by >2 weeks for plants grown on muck soil, but yield was unaffected. When grown on sandy soil, earliness was enhanced from plants grown in 19- and 40-cm3 cells, but head weights were not affected in the spring planting. In fall, heads were heavier for plants grown in 11-, 19-, or 40-cm3 cells compared with those from 2-cm3 cells. On sandy soil, harvest was delayed 13 days in spring and 16 days in fall for plants grown in the smallest cell size. Using the two smaller cell sizes saved medium and space in the greenhouse and increased the root growth ratio, but it led to reduced plant growth compared to using the bigger cells. Yield and earliness were more related to season and soil type than to transplant quality. On sandy soil, plants grown in 2- and 11-cm3 cells matured later, and yield was significantly decreased (8.6%) in fall by using plants from the 2-cm3 cells compared to the other sizes. From our results, compressing the medium in the cells was not justified because it is more costly and did not benefit yield in the field.

scholarly journals Seedling Growth of Catawba Rhododendron. I. Temperature Optima, Leaf Area, and Dry Weight Distribution

HortScience ◽  
1994 ◽  
Vol 29 (11) ◽  
pp. 1298-1302 ◽  
Author(s):  
D. Bradley Rowe ◽  
Stuart L. Warren ◽  
Frank A. Blazich
Keyword(s):  
Leaf Area ◽  
Seedling Growth ◽  
Weight Ratio ◽  
Dry Weight ◽  
High Elevation ◽  
Root Weight ◽  
Root Dry Weight ◽  
Leaf Weight Ratio ◽  
Leaf Weight ◽  
Total Plant

Catawba rhododendron (Rhododendron catawbiense Michx.) seedlings of two provenances, Johnston County, N.C. (35°45′N, 78°12′W, elevation = 67 m), and Yancey County, N.C. (35°45′N, 82°16′W, elevation = 1954 m), were grown in controlled-environment chambers for 18 weeks with days at 18, 22, 26, or 30C in factorial combination with nights at 14, 18, 22, or 26C. Shoot and root dry weights and total leaf areas of seedlings of the Yancey County provenance (high elevation) exceeded (P ≤ 0.05) those of the Johnston County (low elevation) provenance at all temperature combinations. Leaf area was maximal at 22/22C, 18/26C, and 22/26C and minimal at 30/14C (day/night). Shoot dry weight responded similarly. Root dry weight decreased linearly with increasing day temperature, but showed a quadratic response to night temperature. Leaf weight ratio (leaf dry weight: total plant dry weight) increased, while root weight ratio (root dry weight: total plant dry weight) decreased with increasing day temperature. Leaf weight ratio was consistently higher than either stem or root weight ratios. Day/night cycles of 22 to 26/22C appear optimal for seedling growth.

scholarly journals Line × tester analysis for growth and biomass characteristics of Salix

Genetika ◽  
2018 ◽  
Vol 50 (1) ◽  
pp. 95-106
Author(s):  
Sapna Thakur ◽  
N.B. Singh ◽  
Sanjeev Thakur ◽  
J.P. Sharma ◽  
R.K. Gupta ◽  
...  
Keyword(s):  
Recurrent Selection ◽  
Genetic Interaction ◽  
Dry Weight ◽  
Root Weight ◽  
Additive Variance ◽  
Quantitative Characters ◽  
Proportional Contribution ◽  
Total Dry Weight ◽  
Shoot Weight ◽  
Salix Spp

Line ? tester analysis was carried out in willows (Salix spp.) to determine the genetic interaction in the expression of various quantitative characters related to productivity. Combining ability revealed that the estimates of GCA variance (?2 GCA) were more than the SCA variance (?2 SCA) for all the characters studied. Later the gene action study revealed that additive variance was observed more than the dominance variance for all the parameters studied. The proportional contribution of lines were higher than individual contribution of testers or line ? tester interaction except for fresh root weight, dry shoot weight, dry root weight and total dry weight where the contribution of interactions was more. Line PN 227 and tester Austree and J 795 were found to be good general combiners and thus appeared to be worthy of exploiting in Salix improvement through breeding and recurrent selection followed by cloning for developing commercial superior clones. On the basis of mean performance and significant desirable SCA effects, the combinations PN 227 ? Austree, PN 227 ? NZ 1140 and J 799 ? Austree were found to be the most promising families for growth and biomass characters and are recommended for within family selections followed by heterotic breeding.

scholarly journals Alteration of dry matter accumulation under soil moisture fluctuation stress in rice (Oryza sativa L.)

2021 ◽  
pp. 757-763
Author(s):  
Cut Nur Ichsan ◽  
Bakhtiar Basyah ◽  
Sabaruddin Zakaria ◽  
Efendi Efendi
Keyword(s):  
Water Stress ◽  
Dry Matter ◽  
Dry Weight ◽  
Shoot Length ◽  
Root Weight ◽  
Dry Matter Accumulation ◽  
Root Depth ◽  
Rice Varieties ◽  
Root Dry Weight ◽  
Shoot Weight

Drought-flood abrupt alterations (DFAA) is a condition in drought season when sudden rain inundate rice plants. These events are due to the high frequency of extreme climate events that might pose a threat to rice productivity. DFAA causes cumulative stress on rice which affects crop growth and alters dry matter accumulation. This study aims to understand the effect of DFAA to dry matter accumulation by assessing six rice varieties under DFAA. Three treatments were provided such as continuously irrigated as non-water stress (NS) as a control; drought to water stress -35 kPa (DFAA1) followed by sudden flood; drought to severe water stress -70 kPa (DFAA2) followed by abrupt floods; repeated until harvest. The study found that the alteration of dry matter accumulation was determined by root length, root weight, shoot length and shoot weight. Only varieties that are able to increase root depth under water stress fluctuation will be able to maintain the yield. The results of study showed that root depth was positively correlated with shoot length (r = 0.68), shoot weight (r = 0.62), root weight (r = 0.57), percentage of filled grain (r = 0.55) and number of filled grain per hill (r = 0.49). Shoot length was positively correlated with shoot weight (r = 0.83), root weight (r = 0.75) and the number of filled grain (r = 0.62), while shoot weight was only positively correlated with root weight (r = 0.88). This means that only root depth and shoot length can increase the seed setting rate and the number of filled grains per hill. Furthermore, at DFAA2, the percentage of filled grain was highest in Sipulo followed by Bo Santeut, Sanbei, Towuti and Situ Patenggang, which mean that varieties with deeper and heavier root dry weight can maintain higher yields than shallow and low root dry weight. The result of the study may allow to select rice varieties that are resistant to multilevel water-stress and able to maintain the potential yield, by looking at root depth, root dry weight, and through their grain yield in general. These traits could become key indicators for resistance to DFAA stress in rice. It is also necessary to pay attention to the fluctuation of soil water content in critical phases, especially in the reproductive phase and grain filling

Root Development of Bean (Phaseolus vulgaris L.) is Affected by Trifluralin Herbicide

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 471b-471
Author(s):  
Jim E. Wyatt
Keyword(s):  
Leaf Area ◽  
Lateral Roots ◽  
Soil Surface ◽  
Dry Weight ◽  
Root Weight ◽  
Treated Soil ◽  
Snap Beans ◽  
Primary Roots ◽  
Constant Rate ◽  
Loam Soil

The objectives of this study were to investigate the effects of trifluralin (TRI) herbicide on plant vigor and lateral root growth of snap beans. Lexington silt loam soil, which had not been treated with herbicides for at least 3 years, was used in this study. TRI herbicide was mixed with appropriate amounts of soil in a cement mixer to provide a constant rate of 560 g ai/ha TRI. To simulate TRI herbicide incorporation, bands of treated and untreated soil were layered into 30 × 30 × 15 cm (vol 13,500 cm3) bottomless wood boxes. Treatments were 1) control, 2) 2.5-cm treated band placed 2.5 cm below soil surface (BSS), 3) 2.5 cm treated band placed 5.1 cm BSS, 4) top 5.1 cm with treated soil, or 5) top 7.6 cm with treated soil. `Benton' snap beans were planted in each box and grown in the greenhouse for 25 days. Plant measurements made included plant height, leaf area, and fresh and dry weight. The root system of each plant was washed and roots arising from the hypocotyl, transition zone, and primary roots were counted. All roots from each box were combined, dried overnight at 100C and weighed. Plant top weight and leaf area were not affected by TRI treatments. Plants were shorter in all TRI treatments except where placement was banded at 5.1 cm BSS. More adventitious roots were produced on hypocotyls when TRI was applied in a 2.5-cm band at 2.5-cm BSS or in the top 5.1 cm of soil. Total root weight was lower and fewer lateral roots developed in all soil bands treated with TRI.

scholarly journals Effects of Bacillus FS-3 on growth of tomato (Lycopersicon esculentum L.) plants and availability of phosphorus in soil

2008 ◽  
Vol 53 (No. 2) ◽  
pp. 58-64 ◽  
Author(s):  
M. Turan ◽  
N. Ataoglu ◽  
F. Sahin
Keyword(s):  
Lycopersicon Esculentum ◽  
Ammonium Phosphate ◽  
Dry Weight ◽  
P Uptake ◽  
Available Phosphorus ◽  
Root Weight ◽  
Soluble Phosphate ◽  
Triple Superphosphate ◽  
Root Dry Weight ◽  
Phosphate Solubilizing

The effects of phosphate solubilizing bacterium (<i>Bacillus</i> FS-3) application on phosphorus contents of tomato (<i>Lycopersicon esculentum</i> L.) plant, growing performance and phosphorus forms in soil were evaluated under greenhouse condition. Five different phosphorus fertilizer treatments (normal superphosphate, triple superphosphate, di-ammonium phosphate, phosphoric acid, and rock phosphate) with and without bacterium (<i>Bacillus</i> FS-3) were applied in pots as 344 kg P/ha. Basal fertilizers were applied to all the pots as 180 kg N/ha (NH<sub>4</sub>NO<sub>3</sub> 33% N), 100 kg K/ha (K<sub>2</sub>SO<sub>4</sub> 50% K<sub>2</sub>O). The results obtained showed that phosphorus availability from soil increased with phosphate solubilizing bacterium (PSB) application. The amount of plant available form of soil phosphorus fraction (resin-Pi + NaHCO<sub>3</sub>-Pi + NaHCO<sub>3</sub>-Po + NaOH-Pi + NaOH-Po) increased with PSB application. In all fertilizer types, bacteria application converted approximately 20% of less available phosphorus into labile forms. Statistically significant differences were obtained in shoot and root dry weight of tomato plants treated with PSB application. In all of the fertilizers, plant shoot and root weight and P uptake were greater with PSB applications than without PSB. The highest shoot-root dry weight and P uptake of plant were determined in triple superphosphate (TSP) with PSB application treatment. The data in the present study suggest that the application of PSB (FS-3) may increase the availability of soluble phosphate by dissolving the inorganic forms of phosphate and that bacterial strain tested in this study has a potential to be used as a bio-fertilizer in sustainable and organic agriculture.

scholarly journals Effect of applied lead on the growth and accumulation of lead in Indian spinach in three textural groups of soils

2013 ◽  
pp. 113-124
Author(s):  
MG Kibria ◽  
KT Osman ◽  
M Islam ◽  
MJ Ahammad
Keyword(s):  
Lead Concentration ◽  
Sandy Loam ◽  
Dry Weight ◽  
Soil Treatment ◽  
Sandy Loam Soil ◽  
Clay Loam ◽  
Sandy Clay Loam ◽  
Root Dry Weight ◽  
Loam Soil ◽  
Different Levels

Indian spinach (Basella rubra L.) was grown in earthen pots containing soils of three different textures and treated with different levels of lead. The effects of Pb treatments on growth and uptake of Pb were investigated. At the highest dose of Pb ( 50 mg Pb kg-1 soil) leaf, stem and root dry weight of Indian spinach were reduced by 22-34, 11- 43 and 30-47 %, respectively from control in clay loam, sandy clay loam and sandy loam soil, respectively. Lead concentration in leaf, stem and root generally increased with increasing rate of Pb application. The highest Pb concentrations in leaf, stem and root were obtained at 50 mg Pb kg-1 soil treatment and the values were in the ranges from 49.28 to 65.40, 57.72 to 77.51 and 46.69 to 71.78 mg kg-1, respectively. Bioaccumulation coefficients of Pb in leaf, stem and root of Indian spinach were in the ranges of 0.63- 1.94, 0.82-2.21 and 0.37-1.09, respectively. DOI: http://dx.doi.org/10.3329/cujbs.v5i1.13377 The Chittagong Univ. J. B. Sci.,Vol. 5(1 &2):113-124, 2010

scholarly journals Growth and Production of Determinate and Indeterminate Soybean (Glycine max L.) Influenced by Salinity Stress

2020 ◽  
Vol 142 ◽  
pp. 03004
Author(s):  
Danang Adriansyah ◽  
Karno ◽  
Florentina Kusmiyati
Keyword(s):  
Glycine Max ◽  
Plant Height ◽  
Salinity Stress ◽  
Dry Weight ◽  
Root Weight ◽  
Root Dry Weight ◽  
Shoot Dry Weight ◽  
Growth Types ◽  
Shoot Weight ◽  
Pod Number

This research was aimed to determine growth and production of two different growth types of soybean (Glycine max L.) influenced by salinity stress at various levels. This research used Factorial Design based on Completely Randomized Design 2x4 with ten replications. Two soybean growth types were used as the first factor (G1 = Determinate ; G2 = Indeterminate). The second factor was the various levels of soil salinity (S0 = 0.42 dS∙m-1; S1 = 2.93 dS∙m-1; S2 = 4.74 dS∙m-1; S3 = 6.03 dS∙m-1). Data were subjected to analysis of variance and tested further using Tukey’s Honestly Significant Differences (HSD). Parameters observed were plant height (cm), shoot weight (g), shoot dry weight (g), root length (cm), root weight (g), root dry weight (g), and total pod number. Results showed that indeterminate soybean is the best growth type to be planted in salinity stress based on plant height, shoot weight, shoot dry weight, root length, root weight, root dry weight, and total pod number, significantly different from determinate soybean. Salinity stress under 2.93 dS∙m-1 had the better results in plant height, root weight, and root dry weight.

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