The effect of daylength and temperature on the growth and reproduction of six strains of Townsville lucerne (Stylosanthes humilis)

1967 ◽  
Vol 7 (27) ◽  
pp. 351 ◽  
Author(s):  
RW Downes ◽  
IB Staples ◽  
PA Colman ◽  
L Pedley
Keyword(s):  
Seed Yield ◽  
Plant Morphology ◽  
Temperature Treatment ◽  
Growth Characteristics ◽  
Relative Response ◽  
Stylosanthes Humilis ◽  
Stems And Leaves ◽  
Lower Temperature ◽  
Short Days ◽  
Growth And Reproduction

Growth studies of Townsville lucerne were conducted in the phytotron at Canberra to gain an understanding of the relative response of six strains to daylength and temperature. Vegetative growth was promoted by long days in all strains. Some strains flowered under these conditions but other strains appeared to require short days before they were induced to flower. The effect of daylength was reflected in seed yield and in the relative effort that plants devoted to reproduction. In these characters, various strains showed differential responses. For most other characters, a response to daylength was detected, but all strains reacted in a common manner. Weights of roots, stems, and leaves were significantly higher under the lower temperature treatment. A tendency in this direction was also detected in several other characters. Variation among strains in plant morphology and response to photoperiod were pronounced. This suggests a relation between growth characteristics and the ecological background of these strains of Townsville lucerne.

Evidence for inhibitor involvement in thermodormancy of Grand Rapids lettuce seeds

1991 ◽  
Vol 1 (4) ◽  
pp. 263-267 ◽  
Author(s):  
J. G. Chris Small ◽  
Yitzchak Gutterman
Keyword(s):  
High Temperature ◽  
Temperature Treatment ◽  
Small Extent ◽  
High Temperature Treatment ◽  
Ultraviolet Region ◽  
Distilled Water ◽  
Osmotic Effect ◽  
Lettuce Seeds ◽  
Grand Rapids ◽  
Lower Temperature

AbstractProlonged imbibition and incubation of lettuce seeds at a supraoptimal temperature induces secondary dormancy. Such seeds no longer germinate when returned to conditions optimal for germination of non-dormant seeds. The possibility that inhibitors are involved in the induction of thermodormancy was investigated.Washing of thermodormant seeds restored germination to a small extent. However, continuous leaching of seeds during high-temperature treatment with distilled water, largely prevented the induction of thermodormancy. Such seeds were qualitatively similar to nondormant seeds, i.e. they required only light to germinate at a lower temperature and germinated in the dark if given GA3. The germination water from thermodormant seeds inhibited the germination of non-dormant lettuce seeds. The inhibition was not an osmotic effect. Absorbance in the ultraviolet region was higher in germination water from thermodormant seeds than that of non-dormant seeds. It is concluded that inhibitors are involved in the induction of thermodormancy of lettuce seeds.

THE INFLUENCE OF VARIOUS TEMPERATURES AND (2-CHLOROETHYL) TRIMETHYLAMMONIUM CHLORIDE AND (ALLYL) TRIMETHYLAMMONIUM BROMIDE ON PEPPERS AND TOMATOES

1962 ◽  
Vol 42 (1) ◽  
pp. 142-149 ◽  
Author(s):  
H. Tiessen
Keyword(s):  
Total Yield ◽  
Temperature Treatment ◽  
Seedling Stage ◽  
Trimethylammonium Chloride ◽  
Green Plants ◽  
True Leaf ◽  
Different Temperatures ◽  
Lower Temperature ◽  
Field Setting ◽  
Pepper Plants

Fireball tomato and Calwonder pepper plants were subjected, in the seedling stage, to different temperatures and to both drench and foliar applications of (2-chloroethyl) trimethylammonium chloride (CCC) and (allyl) trimethylammonium bromide (AMAB).Seedlings were exposed to minimum night temperatures of 54° to 56°F. and of 64° to 68°F. from the appearance of the first true leaf for 3 weeks for peppers and until field setting (6 weeks) for tomatoes. For both crops the lower temperature treatment gave an increase in early fruit number and yield.Drench applications of 100 milliliters per band to tomatoes and 900 milliliters per square foot to peppers of 10−3 and 10−4 M solutions of CCC or of AMAB produced shorter, stockier, darker-green plants with reduced foliage spread. Growth was further reduced by the lower temperature treatments. Both drenches reduced total yields in both tomatoes and peppers.Foliar treatments of CCC and of AMAB increased the total yield of peppers started at the warmer temperature. At the cooler temperature, however, yield was not affected by the CCC treatment but was reduced by the AMAB treatment. Foliar treatments with either chemical did not affect the total yield of tomatoes after seedling treatment at either temperature.

Comparative Studies of Monoecious and Dioecious Hydrilla (Hydrilla verticillata) Biotypes

Weed Science ◽  
1987 ◽  
Vol 35 (2) ◽  
pp. 204-210 ◽  
Author(s):  
Kerry K. Steward ◽  
Thai K. Van
Keyword(s):  
Hydrilla Verticillata ◽  
Temperature Tolerance ◽  
Injury Threshold ◽  
Growing Seasons ◽  
Northern Areas ◽  
Aquatic Herbicides ◽  
Controlled Environments ◽  
Lower Temperature ◽  
Response To Temperature ◽  
Short Days

Selected biological and physiological parameters of hydrilla [Hydrilla verticillata(L.f.) Royle # HYLLI] biotypes were compared in growth chambers, glasshouse, or outside aquaria. Salinity tolerance was similar for both biotypes with an injury threshold of approximately 13 parts per thousand (ppt). The registered aquatic herbicides diquat (6,7-dihydrodipyrido [1,2-α:2′,1′-c] pyrazinediium ion) and dipotassium and monoamine salts of endothall (7-oxabicyclo [2.2.1] heptane-2,3-dicarboxylic acid)4produced similar injury to both biotypes. Biomass of the monoecious plants, growing in controlled environments, declined under short days. Tuber production in monoecious plants was greatest under short days and was significantly higher than in dioecious plants under the same conditions. Growth response to temperature was similar among all plants and was retarded at 15 C. Tuber germination occurred at lower temperatures in the monoecious plants, which was indicative of a lower temperature tolerance. Vegetative propagules were the only perennating structures observed in the monoecious biotype, and regrowth was entirely from tubers and turions. The annual growth habit, in conjunction with rapid and abundant propagule production, adapts the monoecious biotype to northern areas with short growing seasons.

scholarly journals Polymer Stabilized Liquid Crystal Smart Window with Flexible Substrates Based on Low-Temperature Treatment of Polyamide Acid Technology

Polymers ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 1869 ◽  
Author(s):  
Yang Zhang ◽  
Changrui Wang ◽  
Wei Zhao ◽  
Ming Li ◽  
Xiao Wang ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Temperature Treatment ◽  
Flexible Substrates ◽  
Smart Window ◽  
Alignment Layer ◽  
Low Temperature Treatment ◽  
Electro Optic ◽  
Lower Temperature ◽  
Polymer Stabilized ◽  
Pet Substrate

Polymer stabilized liquid crystal (PSLC) devices can be used as smart privacy windows that switch between transparent and opaque states. The polyimide alignment layer of a PSLC device is usually obtained by the treatment of polyamide acid (PAA) with temperatures over 200 °C. This hinders the fabrication of PSLC devices on flexible substrates, which melt at these high temperatures. In this work, the fabrication of a PSLC alignment layer using a lower temperature that is compatible with most flexible substrates, is demonstrated. It was found that the treatment of PAA at 150 °C could generate the same alignment for liquid crystals. Based on this, a PSLC device was successfully fabricated on a flexible polyethylene terephthalate (PET) substrate, demonstrating excellent electro-optic performances.

Effects of high temperature on the growth and composition of sugarcane internodes

2006 ◽  
Vol 57 (10) ◽  
pp. 1087 ◽  
Author(s):  
G. D. Bonnett ◽  
M. L. Hewitt ◽  
D. Glassop
Keyword(s):  
High Temperature ◽  
Soluble Sugars ◽  
Dry Mass ◽  
Temperature Treatment ◽  
Sucrose Content ◽  
Insoluble Fibre ◽  
Higher Temperature ◽  
Lower Temperature ◽  
Leaf Appearance ◽  
Possible Cause

Sugarcane grown in the Ord River district of Western Australia has lower sucrose content than expected from earlier trials and experience in other irrigated districts. High temperatures have been hypothesised as a possible cause. The effects of high temperature (above 32°C) on growth and carbon partitioning were investigated. A temperature regime of (25–38°C) was compared with (23–33°C). In one experiment, 7-month-old plants of cvv. Q117 and Q158 were subjected to the treatments for 2 months. In another experiment, the plants were allowed to regrow (ratoon) for 6 months. In both experiments, the higher temperature resulted in more, shorter internodes and higher moisture content. Most internodes from plants in the higher temperature treatment had lower sucrose content than internodes from the lower temperature. On a dry mass basis the internodes from the plants in the higher temperature had proportionately more fibre and hexoses but lower sucrose. Combined with an increased number of nodes in a stem of similar or shorter length this would result in higher stalk fibre and lower sucrose content. The data provided evidence that sugarcane partitions less carbon to stored sucrose when grown under high compared with low temperatures. The two cultivars partitioned carbon between soluble (sugars) and insoluble (fibre) fractions to different degrees. These experiments also indicate that the current models describing leaf appearance and perhaps sugarcane growth at temperatures above 32°C, in general, need revision.

Field evaluation following two cycles of backcross transfer of somatic embryogenesis to commercial alfalfa germplasm

1993 ◽  
Vol 73 (1) ◽  
pp. 131-137 ◽  
Author(s):  
S. R. Bowley ◽  
G. A. Kielly ◽  
K. Anandarajah ◽  
B. D. McKersie ◽  
T. Senaratna
Keyword(s):  
Somatic Embryogenesis ◽  
Medicago Sativa ◽  
Seed Yield ◽  
Field Experiments ◽  
Field Evaluation ◽  
Growth Characteristics ◽  
Seed Technology ◽  
Artificial Seed ◽  
Medicago Sativa L

For successful application of artificial seed technology to alfalfa (Medicago sativa L.), parental plants must possess the necessary genes for somatic embryogenesis and produce progeny having high commercial value. A backcross procedure was initiated to transfer the ability to form somatic embryos from genotype A70-34, a selection from the cultivar Rangelander, to multiple-pest-resistant alfalfa germplasm. The objectives of this study were to evaluate the growth characteristics and seed yield of the F1; BC1 and BC2 generations to determine if introgression with commercial germplasm had improved the agronomic features of the embryogenic germplasm. This study consisted of two field experiments, each conducted at two locations. One experiment evaluated herbage growth characteristics and herbage production at Elora and Woodstock, Ontario, and the other evaluated seed yield at Elora and Delhi, Ontario. Significant increases in fall regrowth height, leaflet length:width ratio, and seed yield were detected over the cycles of crossing. By the BC2, fall dormancy and leaflet length:width ratio were similar to those in commercial populations. Although improvements in seed yield were detected, the BC2 was inferior in seed yield compared with commercial germplasm, and further introgression and (or) conscious selection for improved seed yield will be required. Through a population backcross procedure, it appears possible to develop commercial alfalfa germplasm capable of in vitro manipulation. Key words: Alfalfa, Medicago sativa L., somatic embryogenesis, artificial seed, backcross

Variation in flowering time and in some growth characteristics of Townsville lucerne (Stylosanthes humilis)

1965 ◽  
Vol 5 (16) ◽  
pp. 49 ◽  
Author(s):  
DF Cameron
Keyword(s):  
Flowering Time ◽  
Significant Variation ◽  
Growth Habit ◽  
Northern Territory ◽  
Growth Characteristics ◽  
Diameter Growth ◽  
Stylosanthes Humilis ◽  
Stem Colour

Significant variation (P<0.001) in flowering time was found between collections of Townsville lucerne (Styloanthes humilisHBK.) from a number of localities in Queensland and the Northern Territory. Collections also varied in plant diameter, growth habit, stem colour, and degree of hard-seededness. Further avenues of study to elucidate the origin and significance of this variation are briefly discussed.

Genetic diversity of Achillea fragrantissima in Egypt inferred from phenotypic variations and ISSR markers associated with traits of plant size and seed yield

2016 ◽  
Vol 15 (3) ◽  
pp. 239-247 ◽  
Author(s):  
Abdelfattah Badr ◽  
Hanaa H. El-Shazly ◽  
Hanan I. Sayed Ahmed ◽  
Marwa Hamouda ◽  
Eman El-Khateeb ◽  
...  
Keyword(s):  
Seed Yield ◽  
Plant Size ◽  
Issr Markers ◽  
Gulf Of Aqaba ◽  
Phenotypic Traits ◽  
Mountainous Area ◽  
Achillea Fragrantissima ◽  
South Sinai ◽  
Lower Temperature ◽  
High Elevations

Substantial variation in phenotypic traits and ISSR fingerprinting was observed among twenty populations of Achillea fragrantissima (Forssk.) Sch. Bip. in Egypt. Such variation was reflected in the clustering of the examined populations into two major groups: one representing populations in the mountainous area of South Sinai and the other comprising populations growing at low elevations in the middle of Sinai and the desert west of the Suez Canal from Suez in the east to Cairo in the west. Five populations in the eastern part of Sinai near Nuwieba and Taba on the Gulf of Aqaba were loosely assigned to the first group. The populations growing at high elevations in South Sinai, under lower temperature and higher humidity, were characterized by a higher number of total and polymorphic ISSR markers compared with other populations. Unique ISSR markers were more often observed in the fingerprinting of seven populations including five populations growing in the high mountains of Saint Catherine in South Sinai and two populations growing at low elevations but at Wadi Hof south-east of Cairo. Interestingly, unique bands were found in the populations that possessed traits associated with larger plant size and seed yield as well as better vigour. These are important criteria for the selection of A. fragrantissima populations for conservation and sustainable commercial use.

scholarly journals Evaluation of French bean (Phaseolus vulgaris L.) genotypes for seed production

2014 ◽  
Vol 6 (2) ◽  
pp. 594-598
Author(s):  
R. Das ◽  
U. Thapa ◽  
S. Debnath ◽  
Y. A. Lyngdoh ◽  
D. Mallick
Keyword(s):  
Seed Production ◽  
Seed Yield ◽  
Plant Morphology ◽  
French Bean ◽  
Point Of View ◽  
Research Station ◽  
Phaseolus Vulgaris L ◽  
Seed Vigour ◽  
Plant Vigour ◽  
Vigour Index

An experimental study was conducted during 2011/2012 and 2012/2013 at Horticulture Research Station, Mondouri, Bidhan Chandra Krishi Viswavidyalaya, Monhanpur, Nadia, West Bengal, India, to evaluate the performance of fourteen different bush type French bean genotypes for seed yield and to study varietal characterization based on plant morphology. The genotypes, studied under this experiment were namely, Abhay, Shillong Local-3, Arjun, Selection-9, Arka Anoop, Arka Komal, Badshah, Anupam, Arka Suvidha, Falguni, Sonali, Local, Victoria and Vaishnavi-264. From overall point of view of the outcome of the experiment, it has been revealed that genotype with relatively bolder seeds with more number of seeds per pod, and higher bearing capacity per plant generally gives higher seed yield. Among the genotypes under study, Arka Suvidha was the best one as it produced the highest seed yield (2180.92 kg/ha) and relatively good plant vigour and fairly high seed vigour index (2944.38). Falguni and Mohanpur Local also can be considered promising once for seed production point of view.

scholarly journals Effects of HPS and LED lighting on cucumber leaf photosynthesis, light quality penetration and temperature in the canopy, plant morphology and yield

2017 ◽  
Vol 26 (2) ◽  
Author(s):  
Liisa Elina Särkkä ◽  
Kari Jokinen ◽  
Carl-Otto Ottosen ◽  
Timo Kaukoranta
Keyword(s):  
Light Quality ◽  
Stem Elongation ◽  
Plant Morphology ◽  
Light Level ◽  
Yield Potential ◽  
Flower Initiation ◽  
Initiation Rate ◽  
Led Lighting ◽  
Use Efficiency ◽  
Lower Temperature

In Nordic countries during the winter months supplemental lighting is essential for year-round cucumber production. In this research the effects of full HPS (top and interlights) illumination is compared to hybrid (HPS top, LED interlights) and full LED (top and interlights). The results showed that fruit yield was highest in the HPS-LED treatment whereas the electrical use efficiency (kg yield J-1) increased when HPS was replaced with LED. In LED-LED the light use efficiency (g fruit FW mol-1 PAR) was highest but resulted in a fewer number of fruits in mid-winter particularly and the lowest yield potential. The lower temperature and lower light level due to LED-LED lighting lead to reduced photosynthesis capacity, flower initiation rate and water use efficiency whereas increased stem elongation and leaf expansion compared to other treatments. Differences in light quality of LED and HPS are also discussed in terms of cucumber yield formation.

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