Postdormancy development and growth of microsporangiate and megasporangiate strobili of Abies balsamea

1970 ◽  
Vol 48 (2) ◽  
pp. 419-428 ◽  
Author(s):  
G. R. Powell
Keyword(s):  
Moisture Content ◽  
Abies Balsamea ◽  
Pollen Grains ◽  
Dry Weight ◽  
Scale Growth ◽  
Vegetative Buds ◽  
Pollen Release ◽  
Two Stages

Postdormancy development and growth of strobili of Abies balsamea (L.) Mill, are described. Some strobilus growth occurs within the buds before bud swelling becomes detectable. The strobilus buds burst before the vegetative buds. The latter burst about 10 days after the megasporangiate buds, by which time pollen is being shed and the megasporangiate strobili are receptive. Elongation of megasporangiate strobili is divided into two stages; the first, occurring before the strobili are receptive, accompanies the grand period of bract growth; the second accompanies the grand period of ovuliferous-scale growth. The two stages are not evident when growth is expressed as dry weight. Elongation ceases in mid July, but strobilus dry weight increases until mid August. This is largely accounted for by embryo growth in the contained seeds.The moisture content of microsporangiate strobili reaches a maximum just before pollen release. Pollen grains account for about half the mature strobilus dry weight. The moisture content of megasporangiate strobili reaches a maximum at the time of fertilization, after which it declines until the strobili break up.Megasporangiate strobili situated in upper positions become larger than those situated lower in the megasporangiate-strobilus bearing zone.

Seed morphology and ultrastructure in Citrus garrawayi (Rutaceae) in relation to germinability

2007 ◽  
Vol 55 (6) ◽  
pp. 618 ◽  
Author(s):  
Kim N. Hamilton ◽  
Sarah E. Ashmore ◽  
Rod A. Drew ◽  
Hugh W. Pritchard
Keyword(s):  
Moisture Content ◽  
Seed Size ◽  
Seed Coat ◽  
Outer Integument ◽  
Dry Weight ◽  
Seed Morphology ◽  
Embryonic Axis ◽  
Morphological Development ◽  
Seed Moisture Content ◽  
Immature Seeds

Combinational traits of seed size and seed-coat hardness in Citrus garrawayi (F.M.Bailey) (syn. of Microcitrus garrowayi) were investigated as markers for estimation of seed morphological and physiological maturity. Seed size (length) and coat hardness correlated well with changes in seed coat and embryo morphological development, dry-weight accumulation, decreases in moisture content and a significant increase in germinability. Seed moisture content decreased from 82 ± 1% in immature seeds to 40 ± 1% at seed maturation. The outer integument of immature seeds consisted of thin-walled epidermal fibres from which outgrowths of emerging protrusions were observed. In comparison, mature seed coats were characterised by the thickening of the cell walls of the epidermal fibres from which arose numerous protrusions covered by an extensive mucilage layer. Immature seeds, with incomplete embryo and seed-coat histodiffereniation, had a low mean germination percentage of 4 ± 4%. Premature seeds, with a differentiated embryonic axis, were capable of much higher levels of germination (51 ± 10%) before the attainment of mass maturity. Mature seeds, with the most well differentiated embryonic axis and maximum mean dry weight, had the significantly highest level of germination (88 ± 3%).

Study on Drying Characteristics of Microalgae under Different Conditions

2013 ◽  
Vol 724-725 ◽  
pp. 296-299
Author(s):  
Chun Xiang Chen ◽  
Xiao Qian Ma ◽  
Xiao Cong Li ◽  
Wei Ping Qin
Keyword(s):  
Moisture Content ◽  
Mass Loss ◽  
Fresh Water ◽  
Chlorella Vulgaris ◽  
Drying Process ◽  
Drying Time ◽  
Drying Characteristics ◽  
Second Stage ◽  
Drying System ◽  
Two Stages

To find out an alternative of coal saving, a kind of microalgae, Chlorella vulgaris (C. vulgaris) which is widespread in fresh water was studied by digital blast drying system. The effect of the moisture content, drying thickness and temperature on the drying process of C. vulgaris were investigated. The results indicated that when the drying temperature is high, the moisture content is low and the material thickness is small, the drying time is short. The drying process of C.vulgaris can be divided into two stages, and the mass loss is mainly occurred in the second stage . The results will provide guidance for design of drying process and dryer of microalgae.

scholarly journals Reducing Substrate Moisture Content during Greenhouse Production of Poinsettia Improves Postproduction Quality and Economic Value

HortScience ◽  
2018 ◽  
Vol 53 (11) ◽  
pp. 1618-1628
Author(s):  
Yanjun Guo ◽  
Terri Starman ◽  
Charles Hall
Keyword(s):  
Moisture Content ◽  
Economic Value ◽  
Growth Index ◽  
Dry Weight ◽  
Leaf Number ◽  
Stem Length ◽  
Total Production ◽  
Greenhouse Production ◽  
Ethylene Concentration ◽  
Substrate Moisture

The objective was to determine the effect of substrate moisture content (SMC) during poinsettia (Euphorbia pulcherrima) greenhouse production on plant quality, postproduction longevity, and economic value. Two experiments were conducted, one in 2016 with ‘Freedom Red’ and the other in 2017 with ‘Christmas Eve Red’. Treatments included two SMC levels (20% or 40%) applied in four timing of application combinations. Total production (TP) time was 14 (2016) or 12 (2017) weeks in which vegetative production (VP) occurred from week 33 (2016) or 35 (2017) to week 39 and reproductive production (RP) continued from week 40 to 47. The four timing of application treatments were 40/40 = TP at 40% SMC; 20/40 = VP at 20% + RP at 40%; 40/20 = VP at 40% + RP at 20%; 20/20 = TP at 20% SMC. After simulated shipping in the dark, plants were evaluated in a simulated retail environment with two packaging treatments: no sleeve covering or plastic perforated plant sleeves covering container and plant. At the end of greenhouse production, plants grown in 20% SMC during RP (20/20 and 40/20) had shorter bract internode length, stem length, and smaller growth index (GI), decreased shoot and root dry weight (DW), and bract and leaf surface area compared with those in 40% SMC during RP (40/40 and 20/40). Photosynthetic rate was higher when plants were watered at 40% SMC regardless of production stage compared with those in 20% SMC. Leaf thickness, petiole thickness, total bract and leaf number were unaffected by SMC treatments. Plants in 20% SMC during RP (20/20 or 40/20) had earlier bract coloring despite days to anthesis being the same for all SMC treatments. Compared with 40/40, 40/20, and 20/20 could save 44.2% or 43.6%, respectively, irrigation and fertilizer usage, and 39.1% and 47.8%, respectively, labor time. During postharvest, ethylene concentration was unaffected by packaging method. Sleeved plants, regardless of SMC treatment, received lower light intensity in the middle of the plant canopy, causing plants to have lower total leaf number due to abscission and SPAD reading at the end of postproduction. The 40/40 treatment abscised more bracts during five weeks (in 2016) of postproduction and with no sleeve had higher number of bracts with bract edge burn (BEB). In summary, reducing SMC to 20% during TP or RP reduced water usage during production and produced more compact plants with increased postproduction quality.

Seed development in Malva parviflora: onset of germinability, dormancy and desiccation tolerance

2007 ◽  
Vol 47 (6) ◽  
pp. 683 ◽  
Author(s):  
Pippa J. Michael ◽  
Kathryn J. Steadman ◽  
Julie A. Plummer
Keyword(s):  
Moisture Content ◽  
Seed Development ◽  
Desiccation Tolerance ◽  
Dry Weight ◽  
Physical Dormancy ◽  
Seed Moisture Content ◽  
Physiological Maturity ◽  
Seed Moisture ◽  
Physiological Dormancy ◽  
Malva Parviflora

Seed development was examined in Malva parviflora. The first flower opened 51 days after germination; flowers were tagged on the day that they opened and monitored for 33 days. Seeds were collected at 12 stages during this period and used to determine moisture content, germination of fresh seeds and desiccation tolerance (seeds dried to 10% moisture content followed by germination testing). Seed moisture content decreased as seeds developed, whereas fresh (max. 296 mg) and dry weight (max. 212 mg) increased to peak at 12–15 and ~21 days after flowering (DAF), respectively. Therefore, physiological maturity occurred at 21 DAF, when seed moisture content was 16–21%. Seeds were capable of germinating early in development, reaching a maximum of 63% at 9 DAF, but germination declined as development continued, presumably due to the imposition of physiological dormancy. Physical dormancy developed at or after physiological maturity, once seed moisture content declined below 20%. Seeds were able to tolerate desiccation from 18 DAF; desiccation hastened development of physical dormancy and improved germination. These results provide important information regarding M. parviflora seed development, which will ultimately improve weed control techniques aimed at preventing seed set and further additions to the seed bank.

The formation of the tryphine coating the pollen grains of Raphanus , and its properties relating to the self-incompatibility system

1973 ◽  
Vol 184 (1075) ◽  
pp. 149-165 ◽  
Keyword(s):  
Granular Material ◽  
Pollen Grains ◽  
The Self ◽  
Self Incompatibility ◽  
Pollen Maturation ◽  
Incompatible Pollen ◽  
Incompatibility System ◽  
Two Stages ◽  
Stimulation Of ◽  
Incompatible Pollen Tube

The tryphine that coats the pollen grains of Raphanus is tapetally synthesized and is composed of a fibro-granular and a lipidic component. The fibro-granular material is proteinaceous and is secreted by cisternae of the endoplasmic reticulum. The lipidic component is derived, mainly, from degraded elaioplasts. The fibro-granular material is applied to the pollen exine first, followed by the lipidic mass. The tryphine condenses during the final stages of pollen maturation and dries down to form a thick, highly viscous coating. The major part of the condensation appears to result from dehydration. The tryphine, extracted from the pollen by a centrifugal method and mounted in a membrane, appears to be capable of penetrating the outer layers of a stigma of the same species and, if the pollen from which it was derived is incompatible with respect to the stigma, the stimulation of the production of the callosic reaction body in a manner similar to an incompatible pollen tube. It is proposed that, in Raphanus , substances responsible for the initiation of at least two stages in the self-incompatibility system are held in the tryphine.

scholarly journals Evaluating On-demand Irrigation Systems for Container-grown Woody Plants Grown in Biochar-amended Pine Bark

HortScience ◽  
2018 ◽  
Vol 53 (12) ◽  
pp. 1891-1896 ◽  
Author(s):  
Nastaran Basiri Jahromi ◽  
Amy Fulcher ◽  
Forbes Walker ◽  
James Altland ◽  
Wesley Wright ◽  
...  
Keyword(s):  
Plant Growth ◽  
Moisture Content ◽  
Water Use ◽  
Dry Weight ◽  
Irrigation Scheduling ◽  
Total Water ◽  
On Demand ◽  
Substrate Moisture ◽  
Silver Dollar ◽  
Conventional Irrigation

Controlling irrigation using timers or manually operated systems is the most common irrigation scheduling method in outdoor container production systems. Improving irrigation efficiency can be achieved by scheduling irrigation based on plant water needs and the appropriate use of sensors rather than relying on periodically adjusting irrigation volume based on perceived water needs. Substrate amendments such as biochar, a carbon (C)-rich by-product of pyrolysis or gasification, can increase the amount of available water and improve irrigation efficiency and plant growth. Previous work examined two on-demand irrigation schedules in controlled indoor (greenhouse) environments. The goal of this study was to evaluate the impact of these on-demand irrigation schedules and hardwood biochar on water use and biomass gain of container-grown Hydrangea paniculata ‘Silver Dollar’ in a typical outdoor nursery production environment. Eighteen independently controlled irrigation zones were designed to test three irrigation schedules on ‘Silver Dollar’ hydrangea grown in pine bark amended with 0% or 25% hardwood biochar. The three irrigation schedules were conventional irrigation and two on-demand schedules, which were based on substrate physical properties or plant physiology. Conventional irrigation delivered 1.8 cm water in one event each day. The scheduling of substrate-based irrigation was based on the soilless substrate moisture characteristic curve, applying water whenever the substrate water content corresponding to a substrate water potential of –10 kPa was reached. The plant-based irrigation schedule was based on a specific substrate moisture content derived from a previously defined relationship between substrate moisture content and photosynthetic rate, maintaining the volumetric water content (VWC) to support photosynthesis at 90% of the maximum predicted photosynthetic rate. Total water use for the substrate-based irrigation was the same as for the conventional system; the plant-based system used significantly less water. However, plant dry weight was 22% and 15% greater, water use efficiency (WUE) was 40% and 40% greater, and total leachate volume was 25% and 30% less for the substrate-based and plant-based irrigation scheduling systems, respectively, than for conventional irrigation. The 25% biochar amendment rate reduced leachate volume per irrigation event, and leaching fraction, but did not affect total water use or plant dry weight. This research demonstrated that on-demand irrigation scheduling that is plant based or substrate based could be an effective approach to increase WUE for container-grown nursery crops without affecting plant growth negatively.

scholarly journals Physiological quality of pink pepper seeds (Schinus terebinthifolia Raddi.) as a function of storage

2021 ◽  
Vol 38 (1) ◽  
pp. 144-157
Author(s):  
Thaísa De Oliveira Silveira ◽  
Madelon Rodrigues Braz ◽  
Gilmara Pires de Moura Palermo ◽  
Tiago Böer Breier
Keyword(s):  
Moisture Content ◽  
Storage Time ◽  
Storage Period ◽  
Seed Storage ◽  
Dry Weight ◽  
Native Forest ◽  
Alternative Source ◽  
Physiological Quality ◽  
And Storage

Seeds of native forest species for food and seedling production have a growing demand that impacts the need for studies involving seed storage in order to maintain good levels of germination quality. Thus, scientific analyzes that explore the physiological potential of the seeds of these species are necessary, especially for the pink pepper (Schinus terebinthifolia Raddi.), a species used as an alternative source of income for traditional communities and which has been arousing interest due to the consumption of its fruits as a condiment in the national and international market. This work aimed to assess the physiological quality of pink pepper seeds according to the storage period and seed size. The seeds came from a rural settlement, a pioneer in the extraction of pink pepper, in the state of Rio de Janeiro, Brazil. The seeds were evaluated for moisture content, germination, first count, length and dry weight of the germinated seedlings, during the period of time that they remained stored and the size of the seeds. The results allowed to conclude that: i) the germinative percentage of the stored pink pepper seeds decreased over the months; ii) the moisture content of the seeds decreased over the months evaluated iii) the different sizes of seeds did not show differences in germination and storage time and iv) values of length and dry weight of the seedlings did not differ according to the period of storage.

scholarly journals Analysis of Nutritional Composition in 23 Kinds of Edible Fungi

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Qiannan Yu ◽  
Meijuan Guo ◽  
Bin Zhang ◽  
Hao Wu ◽  
Yan Zhang ◽  
...  
Keyword(s):  
Moisture Content ◽  
Protein Content ◽  
Dietary Fiber ◽  
Nutritional Value ◽  
Dry Weight ◽  
Nutritional Composition ◽  
Ash Content ◽  
National Standard ◽  
Edible Fungi ◽  
Standard Methods

To explore the differences in the main nutritional composition of 23 kinds of common edible fungi in the market, the moisture, ash, protein, fat, dietary fiber, carbohydrates, polysaccharides, and energy were analyzed using national standard methods. The results showed that the 23 kinds of edible fungi varied greatly in nutritional composition. Based on dry weight, the moisture content was 6.9∼15.5 g/100 g, the ash content ranged from 1.3 to 10.1 g/100 g, the protein content ranged from 8.5 to 36.9 g/100 g, the fat content was 0.5∼3.9 g/100 g, the dietary fiber content was between 14.4∼70.2 g/100 g, the carbohydrate content is 0.5∼37.3 g/100 g, the polysaccharide content was 2.1∼8.3 g/100 g, and the energy is about 751∼1322 100 g/kJ. All the 23 kinds of edible fungi can be regarded as high-protein low-fat foods, which have their own advantages in terms of nutritional value. This study provides reference for people to use edible fungi in a more scientific and reasonable way.

scholarly journals MOISTURE CHANGES IN LODGEPOLE PINE BEFORE AND AFTER ATTACK BY THE MOUNTAIN PINE BEETLE

1961 ◽  
Vol 37 (4) ◽  
pp. 368-375 ◽  
Author(s):  
R. W. Reid
Keyword(s):  
Moisture Content ◽  
Mountain Pine Beetle ◽  
Lodgepole Pine ◽  
Dry Weight ◽  
Moisture Loss ◽  
Mountain Pine ◽  
Pine Beetle ◽  
Before And After ◽  
Blue Stain ◽  
One Year

The moisture content of the outer sapwood of non-infested lodgepole pine is normally about 85 to 165 per cent of oven dry weight. In trees that have been infested by the mountain pine beetle for one year, the sapwood moisture content can be as low as 16 per cent. There is a steep moisture gradient from about 160 per cent in the outer sapwood to about 30 per cent in the heart-wood. The moisture content in the centre is slightly higher than in the adjacent wood. In infested trees the sapwood moisture is greatly reduced within a year after the attack but moisture in the heartwood is not altered appreciably. Trees infested early in the season drop to a lower moisture content by fall than trees infested later in the season. In non-infested trees there is a diurnal and a seasonal moisture march; these do not occur in infested trees. The rapid moisture loss in the sapwood of infested trees is associated with blue-stain infection and successful establishment of bark-beetle broods

scholarly journals The effect of lime Ca(OH)2 to the constant of granulation rate (k) of Sidoarjo mud (LuSi) and its grain size distribution

2019 ◽  
Vol 276 ◽  
pp. 05010
Author(s):  
Dasyri Pasmar ◽  
Noor Endah Mochtar ◽  
Ali Altway
Keyword(s):  
Grain Size ◽  
Moisture Content ◽  
Water Temperature ◽  
Size Distribution ◽  
Grain Size Distribution ◽  
Inclination Angle ◽  
Rotation Rate ◽  
Water Resistance ◽  
Dry Weight ◽  
Granulation Process

Sidoarjo mud (LuSi) is very hot and sticky mud-like substance produced by eruption of Kujung, Kalibeng, and Pucangan formations caused by well exploration for gas in Porong, Sidoarjo, East Java, Indonesia. LuSi submerged villages, industrial areas, and rice fields in Porong. The eruption is still taking place so that it needs more area and higher dike surrounded to retain the mud. Therefore, it is very urgent to use LuSi in huge volumes such as for borrowed materials. LuSi grain size and its strength, however, do not meet the borrowed materials requirement. Therefore, the grain size was improved using granulator drum and lime Ca(OH)2 was used to increase its strength. The grain size produced by granulator was affected by length, diameter, and rotation rate of granulator drum, and also by constant of granulation rate ‘k’ that was function of other parameters, inclination angle of granulator drum (S), moisture content (W), and water temperature (T). The results show that lime needed for stabilization is 10% of LuSi dry weight. The “k” is affected by lime where parameters (S) and (W) become smaller and (T) is higher. Lime also produces dryer granular, higher water resistance, and shorter granulation process. Besides, higher water temperature during granulation process is needed to develop bigger grain size for granular stabilized-LuSi.

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