scholarly journals The seed water content as a time-independent physiological trait during germination in wild tree species such as Ceiba aesculifolia

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Ximena Gómez-Maqueo ◽  
Diana Soriano ◽  
Noé Velázquez-Rosas ◽  
Sandra Alvarado-López ◽  
Karina Jiménez-Durán ◽  
...  
Botany ◽  
2009 ◽  
Vol 87 (1) ◽  
pp. 88-96 ◽  
Author(s):  
Pedro E. Gundel ◽  
M. Alejandra Martínez-Ghersa ◽  
Lucas A. Garibaldi ◽  
Claudio M. Ghersa

Neotyphodium endophyte fungi are vertically transmitted symbionts of cool-season grasses. The seed phase of the grass’ life cycle appears to be critical for the persistence of the fungus. Endophyte viability decreases faster than seed viability, but little is known of the effects of this endophyte on seed viability. The endophyte could affect seed viability through changes in water content. Here, we assessed the effects of the endophyte on seed viability, the differential survival of endophyte and seed, and the effects of infection on seed water content. Viability of endophyte-infected and noninfected seeds and endophyte were evaluated over a period of 729 d under 12 controlled environmental conditions. Seed viability was reduced by the infection at high temperature and high relative humidity, but not under other conditions. Moreover, endophyte viability decreased faster than seed viability only under high humidity or high temperature. Seed water content was not affected by endophyte presence. The proportion of viable infected seeds was mainly affected by the loss in endophyte viability and secondly by the differential survival of infected and noninfected seeds. Knowledge on the relative importance of these processes is critical to understand the factors affecting the efficiency of endophyte vertical transmission and the frequency of endophyte-infected plants.


Forests ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 1227
Author(s):  
Moein Farahnak ◽  
Keiji Mitsuyasu ◽  
Takuo Hishi ◽  
Ayumi Katayama ◽  
Masaaki Chiwa ◽  
...  

Tree root system development alters forest soil properties, and differences in root diameter frequency and root length per soil volume reflect differences in root system function. In this study, the relationship between vertical distribution of very fine root and soil water content was investigated in intact tree and cut tree areas. The vertical distribution of root density with different diameter classes (very fine <0.5 mm and fine 0.5–2.0 mm) and soil water content were examined along a slope with two coniferous tree species, Cryptomeria japonica (L.f.) D. Don and Chamaecyparis obtusa (Siebold et Zucc.) Endl. The root biomass and length density of very fine roots at soil depth of 0–5 cm were higher in the Ch. obtusa intact tree plot than in the Cr. japonica intact plot. Tree cutting caused a reduction in the biomass and length of very fine roots at 0–5 cm soil depth, and an increment in soil water content at 5–30 cm soil depth of the Ch. obtusa cut tree plot one year after cutting. However, very fine root density of the Cr. japonica intact tree plot was quite low and the soil water content in post-harvest areas did not change. The increase in soil water content at 5–30 cm soil depth of the Ch. obtusa cut tree plot could be caused by the decrease in very fine roots at 0–5 cm soil depth. These results suggest that the distribution of soil water content was changed after tree cutting of Ch. obtusa by the channels generated by the decay of very fine roots. It was also shown that differences in root system characteristics among different tree species affect soil water properties after cutting.


2005 ◽  
Vol 143 (2-3) ◽  
pp. 183-192 ◽  
Author(s):  
F. COSTE ◽  
M. P. RAVENEAU ◽  
Y. CROZAT

A non-destructive indicator of seed water content could significantly help crop scientists with assessment of the effects of environmental conditions during drying on grain qualities or on seed physiological quality. This is particularly important for grain legumes which simultaneously bear pods of different ages. Visual assessment of pod colour has so far been used to date grain legume stages, but now colour can be easily and accurately measured with a portable spectrophotometer. Relationships between the spectrophotometer measurements and the pod and seed water contents were tested in various climatic contexts (3 years: 2000, 2001, 2002; field or greenhouse, two or three sowing dates) for two bean cultivars (Booster and Calypso) and also for one pea cultivar (Baccara) in 2003 near Angers, France. Among the different spectrophotometer measurements, hue angle (h) clearly shows the transition from green (h=180 °) to yellow (h=90 °) and then to red (h=0 °). In each context, h and seed water content (SWC) relationships showed the same pattern of three linear phases: first a steady state; then a sharp decrease from green (h=106–108 °) to yellow (h=85–93 °) just before the end of the seed filling stage for Booster or between the end of the seed filling phase and the beginning of seed drying for Calypso and pea; finally, a slow decrease from yellow to ochre (h=75–78 °) during seed drying. For each bean cultivar, the parameters of the linear relationships showed no differences between maturation conditions. Therefore, 6 h classes matching six SWC classes could be defined over a wide range of SWC between 0·56 and 0·2 g/g for Booster. However for Calypso and pea, only 3 h classes could be defined because of the tight relationships between h and SWC during the end of seed drying, which can be explained by pod walls drying faster than seeds. Hence, spectrophotometer measurements, if calibrated for a given cultivar of a species, could now be used to select pods with seeds of the same water content and therefore to study environmental effects on quality criteria either in controlled conditions or in the field.


2020 ◽  
Vol 43 (12) ◽  
pp. 3048-3067 ◽  
Author(s):  
Kasia Ziemińska ◽  
Emily Rosa ◽  
Sean M. Gleason ◽  
N. Michele Holbrook

2020 ◽  
Author(s):  
Kasia Zieminska ◽  
Emily Rosa ◽  
Sean Gleason ◽  
N. Michele Holbrook

&lt;p&gt;Water released from storage into the transpiration stream (termed: capacitance) can play an important role in tree every day hydraulic functioning as well as in tree drought response. However, anatomical underpinnings of capacitance and water storage remain unclear, impeding better understanding of capacitance mechanisms. Across 30 temperate angiosperm tree species, we measured &lt;em&gt;in natura&lt;/em&gt; twig wood diurnal capacitance and water content, wood density and anatomical properties: vessel dimensions, tissue fractions and vessel-tissue contact fractions (proportion of vessel circumference in contact with other tissues). We found that wood density and predawn lumen volumetric water content (proportion of wood volume that is occupied by water in lumen) together were the strongest predictors of capacitance (&lt;em&gt;r&lt;sub&gt;adj&lt;/sub&gt;&lt;/em&gt;&lt;sup&gt;2&lt;/sup&gt;=0.44***). Vessel-tissue contact fractions&amp;#8212;vessel-ray, vessel-axial parenchyma and vessel-fibre&amp;#8212;each explained an additional &amp;#8764;10% of variation in capacitance. Parenchyma fraction did not correlate with capacitance challenging the common assumption that parenchyma acts as the main source of capacitance water. Anatomical structure, water content and capacitance relationships differed significantly between diffuse-porous and ring-porous species. Predawn relative water content (water in a fresh sample relative to saturated sample) was on average 0.65&amp;#177;0.13 implying that parts of wood were devoid of water.&lt;/p&gt;


2020 ◽  
Vol 21 (8) ◽  
Author(s):  
Muhammad Fajri ◽  
Pratiwi PRATIWI ◽  
Yosep Ruslim

Abstract. Fajri M, Pratiwi, Ruslim Y. 2020. The characteristics of Shorea macrophylla’s habitat in Tane’ Olen, Malinau District, North Kalimantan Province, Indonesia. Biodiversitas 21: 3454-3462.  Shorea macrophylla is a tree species in Tane' Olen forest area. This study analyzed the soil’s physical and chemical properties, topography, and microclimate of S. macrophylla’s habitat. A purposive method was used to select a sampling plot and to place the subplots. Soil was analyzed to determine the physical properties, i.e., texture, bulk density, porosity, and water content, and the chemical properties, i.e., pH, CEC, total N, organic C, C/N ratio, P, K , and Al saturation. Importance value index was determined for each tree species to know the species composition in the study site. Only the dominant species were presented. The soil at the study site had bulk density of 0.60-1.31 gram cm³-1, porosity 50.60%-77.35%, water content 34.88%-95.37%, and soil texture sandy clay. The chemical properties of the soil were as follows: pH was 3.6-4.8, N 0.05%-0.19%, organic C 1.40%-3.65%, P 0.41-1.22 mg 100 gr-1, K 58.68-232.55 mg 100 gr-1, and Cation Exchange Capacity (CEC) 5.35-10.81 meg 100gr -1. Slope ranged between 0 and 25%. The microclimate characteristics were as follows: temperature was 24-26.5°C, relative humidity 76-87%, and light intensity 145-750 Lm. Trees species with an IVI ≥ 10% were S. macrophylla, Madhuca spectabilis, Myristica villosa Warb, Scorodocarpus borneensis, Eugenia spp., Palaquium spp., Macaranga triloba, Syzygium inophyllum and Shorea sp. Positive associations were observed between S. macropylla and S. borneensis, Eugenia spp., Palaquium spp.. and M. triloba, and negative associations were observed between S. macropylla and M. spectabilis, M. villosa Warb, S. inophyllum, and Shorea sp. S. macrophylla grows on riversides with flat and gentle topography, acidic soil, and lower fertility but with suitable microclimate. This species can be recommended to be planted in degraded tropical forest areas but the microclimate and soil properties should be taken into account.


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