scholarly journals Variation in Morphological and Physiological Characteristics of Wild Elymus nutans Ecotypes from Different Altitudes in the Northeastern Tibetan Plateau

2020 ◽  
Vol 2020 ◽  
pp. 1-11 ◽  
Author(s):  
Juan Qi ◽  
Wenhui Liu ◽  
Ting Jiao ◽  
Ann Hamblin
Keyword(s):  
Tibetan Plateau ◽  
Photosynthetic Rate ◽  
Native Species ◽  
Dry Matter ◽  
Root Carbon ◽  
Northeastern Tibetan Plateau ◽  
Shoot Ratio ◽  
Root Shoot Ratio ◽  
Elymus Nutans ◽  
Different Altitudes

The availability of suitable native plant species for local animal husbandry development and ecological restoration is limited on the Qinghai-Tibetan Plateau. Therefore, comparisons of the ecological adaptability of native species to alternative habitats and their introduction into new habitats are of high importance. This study is aimed at identifying the alteration in morphological and physiological characteristics by measuring photosynthetic physiology, nutrient content, and growth associated with adaptation of plants to conditions at different altitudes 2450, 2950, 3100, and 3300 m above sea level (a. s. l.) on the plateau. Seeds of the dominant grass, Elymus nutans, were collected from locations at these altitudes and grown at a test location of 2950 m a. s. l. Results indicated that altitude had no significant effect on plant height and root depth. However, the leaf area and total root surface area of plants derived from 2950 and 3300 m a. s. l. showed a parabolic response, being greater than those of plants derived from the lowest (2450 m) and highest (3300 m a. s. l.). Total (root plus shoot) dry matter reduced progressively from 2450 to 3300 m a. s. l, while root : shoot ratio increased progressively with altitude. Seed yield of plants originating from the test altitude (2950 m a. s. l) was significantly higher than at any other altitude, being 20% lower at 2450 m, and 38% and 58% less in populations originating from the higher altitudes (3100 and 3300 m a. s. l.). There was also a parabolic decline in response of Elymus nutans germplasm from 3100, 3300, and 2450 m, compared with plants from 2950 m a. s. l., to photosynthetic rate, total N, soluble sugar, and starch contents. Germplasm from 2450 m a. s. l. had significantly lower shoot and higher root carbon content, lower shoot nitrogen, and lower root carbon-to-nitrogen ratio compared with plants derived from the other three altitudes. It is suggested that the stable, genetically determined morphological and physiological features of ecotypes showed parabolic responses which means these ecotypes have become adapted to local habitats, whereas parameters such as dry matter, total root : shoot ratio, photosynthetic rate, and intercellular CO2 concentration of plants reflected phenotypic linear response to current abiotic conditions. It is postulated that introduced ecotypes from 2450, 3100, and 3300 m could adapt to the environment at 2950 m a. s. l. gradually. We conclude that the increased thermal regime experienced by plants introduced from high altitude to low altitude may facilitate the increased growth of Elymus nutans subtypes. It is important to preserve local strains of native species, or ecotypes, for reintroduction into degraded environments and to maintain the greatest ecosystem stability in the northeastern Tibetan Plateau.

scholarly journals Initial development and gas exchange of Talisia subalbens (Mart.) Radlk. under different shading conditions

2011 ◽  
Vol 35 (1) ◽  
pp. 61-67 ◽  
Author(s):  
Fernanda Carlota Nery ◽  
Hilton Morbeck de Oliveira ◽  
Amauri Alves de Alvarenga ◽  
Sara Dousseau ◽  
Evaristo Mauro de Castro ◽  
...  
Keyword(s):  
Gas Exchange ◽  
Native Species ◽  
Cultivated Plants ◽  
Initial Growth ◽  
Initial Development ◽  
Basal Diameter ◽  
Shoot Ratio ◽  
Root Shoot Ratio ◽  
Significant Difference ◽  
Different Levels

Ecophysiological studies under semi-controlled conditions in nurseries and greenhouses are essential to enable the use of native species to recover degraded areas and for commercial planting. Talisia subalbens (Mart) Radlk, 'cascudo', is a native fruiting species of the Cerrado on the verge of extinction. The ecophysiological performance of this species was evaluated in nursery conditions under different levels of shading (full sunshine, 30%, 50% and 70%). Initial growth, biomass allocation, gas exchange and chlorophyll content of the plants were analyzed. Full sunshine cultivated plants showed a higher accumulation of total, shoot, and root dry biomass. There was no significant difference in the root/shoot ratio among the treatments. Seedlings cultivated under full sunshine and 30% shading showed higher values for height, basal diameter, and leaf area. Differences in stomata conductance and photosynthesis rate were not observed among the different shading levels. Plants cultivated under 70% of shading had higher contents of chlorophyll a, b, and total. During the initial phase with higher levels of radiation were fundamental for the development of T. subalbens seedlings.

scholarly journals Utilização de macrófitas aquáticas em substrato para a produção de mudas de moringa

2016 ◽  
Vol 36 (85) ◽  
pp. 25 ◽  
Author(s):  
Walda Monteiro Farias ◽  
Leonaldo Alves de Andrade ◽  
Manoel Bandeira de Albuquerque ◽  
João Rodrigues da Cunha
Keyword(s):  
Water Hyacinth ◽  
Dry Matter ◽  
Aquatic Macrophytes ◽  
Moringa Oleifera ◽  
Water Lettuce ◽  
Relative Growth ◽  
Substrate Composition ◽  
Crown Diameter ◽  
Shoot Ratio ◽  
Root Shoot Ratio

A utilização de macrófitas aquáticas na composição de substratos para produção de mudas de moringa constitui uma alternativa sustentável. Portanto, objetivou-se com esta pesquisa avaliar o desenvolvimento de mudas de moringa, utilizando subtratos com macrófitas aquáticas, e determinar os teores de N, P e K nas mudas. Utilizaram-se diferentes combinações de macrófitas (M), esterco bovino (E) e terra vegetal (TV) para compor os subtratos. O experimento foi conduzido em esquema fatorial 3 × 4, em delineamento em blocos casualizados com quatro repetições. Foram avaliados: alturas das plantas, diâmetro da copa e caule, taxa relativa de crescimento em altura, em diâmetro da copa e do caule, matéria seca da parte aérea e raízes, comprimento de raízes e razão raízes/parte aérea, além dos teores de N, P e K das mudas. As mudas de moringa apresentam crescimento reduzido quando produzidas em substratos constituídos unicamente com taboa. Alface d’água e os substratos compostos por 60% M + 30% E + 10% TV e 70% M + 30% E, proporcionaram melhor nutrição e crescimento das mudas de moringa. O substrato 60M+30E+10TV composto pelo aguapé e taboa promoveram maior aporte de P para as mudas de moringa.Use of aquatic macrophytes in substrate composition to produce moringa The use of aquatic macrophytes in substrate composition to produce seedlings of moringa is a sustainable alternative. Therefore, the objective of this research was to evaluate the development of moringa seedlings using substrates composed with aquatic macrophytes, and to determine concentrations of N, P and K in the seedlings. We used different combinations of weeds (M), manure (E) and topsoil (TV) to compose the substrates. The experiment was conducted in a 3 × 4 factorial in randomized arrangement with four replications. We evaluated plant height, crown diameter and stem, relative growth rate in height, canopy diameter and in stem, dry matter of aerial part and of roots, root length and root/shoot ratio, besides the content of N, P and K in seedlings. Moringa seedlings showed reduced growth when produced in substrates composed only with cattail. Water lettuce and substrates composed of 60% M + 30%E + 10 % TV and 70% M + 30% E, promoted greater nutrition and growth of moringa seedlings. The substrate 60M +30E +10TV composed by water hyacinth and cattail resulted in greater amount of P in moringa seedlings.Index terms: Organic compound;Typha domingensis;Moringa oleifera

scholarly journals EVALUATION OF FUNGICIDES AGAINST PHYTOPHTHORA AND FUSARIUM (root rot spp.) OF CITRUS ROOTSTOCKS SEEDLINGS

2021 ◽  
pp. 145-154
Author(s):  
Shakila Yasmeen ◽  
Muhammad Mumtaz Khan ◽  
Saeed Ahmad ◽  
Mazhar Abbas ◽  
Bushra Sadia ◽  
...  
Keyword(s):  
Stomatal Conductance ◽  
Photosynthetic Rate ◽  
Transpiration Rate ◽  
Root Rot ◽  
Fungal Pathogens ◽  
Weight Ratio ◽  
Dry Weight ◽  
Shoot Ratio ◽  
Root Shoot Ratio ◽  
Maximum Root

Citrus is one of the most important fruit crop in the world and is usually grown through grafting technique. Rootstock is one of the significant part in grafted plants and has crutial effect on production, including yield, fruit quality, tree size, tolerance to salts and diseases, and scion compatibility. Citrus is susceptible to several fungal pathogens causing incalculable losses to the crop. Among all soil-borne fungal pathogens, Phytophthora and Fusarium cause the most severe damage to the nursery or orchards plants. This research was planned to evaluate the effectiveness of fungicides as soil drenching and root dipping to control Phytophthora and Fusarium attacking citrus rootstock seedlings at the nursery stage. Different physiological and morphological parameters were studied in the infected plants and data were compared with that of control. The data were recorded and compared concerning rootstock seed and seeding response using standard measures and statistical analysis. The results showed that plants inoculated with Phytophthora and Fusarium root rot spp.when treated with Aliette and Ridomil Gold showed maximum root shoot ratio, fresh dry weight ratio, photosynthetic rate, stomatal conductance, water potential and transpiration rate as compared to untreated plants. The results also depicted that plants treated with Aliette and Ridomil Gold through soil drenching have maximum root shoot ratio, fresh dry weight ratio, photosynthetic rate, stomatal conductance and transpiration rate as compared to root dipped plants. Keywords: Fungal diseases, pathogens, root rot, nursery plants.

scholarly journals Performance of physiological basis of rice hybrids under system of rice cultivation

2015 ◽  
Vol 43 (3) ◽  
pp. 359-361
Author(s):  
Pushpraj Singh ◽  
IM Khan ◽  
Smita Singh ◽  
RK Tiwari ◽  
UN Shukla ◽  
...  
Keyword(s):  
Grain Yield ◽  
Chlorophyll Content ◽  
Root Length ◽  
Dry Matter ◽  
Rice Cultivation ◽  
Physiological Basis ◽  
Straw Yield ◽  
Shoot Ratio ◽  
Root Shoot Ratio

Among the rice hybrids, PRH-10 recorded significantly highest chlorophyll content, dry matter, LAI, CGR, RGR, NAR, root length, root: shoot ratio and grain yield (9.95 t/ha) over the rest of hybrids followed by NPH-567. The lowest values of these parameters were noted in IR-36. The higher straw yield was recorded (144.8 t/ha) in NPH-567. DOI: http://dx.doi.org/10.3329/bjb.v43i3.21614 Bangladesh J. Bot. 43(3): 359-361, 2014 (December)

scholarly journals Trinexapac-ethyl causes stimulatory effect on eucalyptus initial growth under nutritional deficiency

2018 ◽  
Vol 48 (1) ◽  
pp. 94-100 ◽  
Author(s):  
Allan Lopes Bacha ◽  
Pedro de Figueiredo Rocha Barbosa Martins ◽  
Pedro Luis da Costa Aguiar Alves ◽  
Rinaldo Cesar de Paula
Keyword(s):  
Dry Matter ◽  
Phosphorus Deficiency ◽  
Complete Solution ◽  
Nutrient Supply ◽  
Nutritional Deficiency ◽  
Initial Growth ◽  
Application Time ◽  
Shoot Ratio ◽  
Root Shoot Ratio ◽  
Positive Effect

Eucalyptus plants are sensitive to abiotic stresses in their initial growth, and nutritional deficiency is one of the most recurrent among them. Trinexapac-ethyl, which is a plant growth regulator, can positively affect eucalyptus, a response known as hormesis, possibly providing plants with greater tolerance to stress. The objective of this study was to evaluate the effect of trinexapac-ethyl at two application times, before planting (BP) or after planting (AP), in Eucalyptus urophylla under conditions of nutritional deficiency (NPK). Two experiments (one for each application time) were conducted simultaneously during 81 days after planting of eucalyptus in 15 L pots. The treatments consisted of three doses of trinexapac-ethyl (0, 30, and 60 g a.i.·ha−1) and four variations of nutrient supply: complete solution (NPK) and solutions without nitrogen (−N), without phosphorus (−P), and without potassium (−K). The variables of gas exchange, growth, and dry matter were evaluated. For both application times, trinexapac-ethyl had a positive effect on the root–shoot ratio of plants grown in −N and also positively affected some eucalyptus photosynthetic characteristics. In the AP application, the compound provided gains in height and dry matter, regardless of the nutrient supply. Under phosphorus deficiency, trinexapac-ethyl provided gains in total dry matter (BP) and leaf area (AP).

Seasonal dynamics of dry weight, growth rate and root/shoot ratio in different aged seedlings of Salix caprea

Biologia ◽  
2006 ◽  
Vol 61 (4) ◽  
Author(s):  
Jiří Dušek ◽  
Jan Květ
Keyword(s):  
Dry Matter ◽  
Dry Weight ◽  
Average Density ◽  
Habitat Conditions ◽  
Salix Caprea ◽  
Weight Growth ◽  
Shoot Ratio ◽  
Root Shoot Ratio ◽  
Matter Production ◽  
Dry Weight Growth

AbstractWillows (e.g. Salix caprea L.) are deciduous and richly branched shrubs or small trees. Salix caprea shows a high adaptability to different habitat conditions. One way of evaluating this adaptability is to measure willow biomass and production. Young plants of S. caprea were sampled from the bottom of an artificial lagoon in which sediments removed from the local Vajgar fishpond were deposited. The bottom of the lagoon was overgrown by vegetation dominated by seedlings of the willows S. caprea and S. aurita. Willows grew in the lagoon at average density of 58 plants per m2. The biomass production and growth of S. caprea were determined for 15 samples (collected from 315 individuals) during the growing season. Annual net dry matter production in the whole community was estimated for 2.7 kg m−2. Willows are generally considered to be fast-growing plants. The highest RGR of willows recorded by us was 0.03 to 0.04 g g−1 d−1 both in the stems and roots. This value was often recorded from July to August.

Effects of Single-seed Sowing on Root Growth, Root-shoot Ratio, and Yield inPeanut (Arachis hypogacaL.)

2013 ◽  
Vol 39 (12) ◽  
pp. 2228 ◽  
Author(s):  
Ye FENG ◽  
Feng GUO ◽  
Bao-Long LI ◽  
Jing-Jing MENG ◽  
Xin-Guo LI ◽  
...  
Keyword(s):  
Root Growth ◽  
Single Seed ◽  
Shoot Ratio ◽  
Root Shoot Ratio ◽  
Seed Sowing
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