Pertumbuhan dan Produktivitas Daun Lamun Thalassia hemprichii (Ehrenb) Ascherson di Perairan Tanjung Benoa, Bali

Thalassia hemprichii is one of the seagrass as favorite food of two protected herbivores such as Green Turtle and Dugong. The existence of Thalassia hemprichii and knowing the growth rate becomes very important for sustainability of two herbivores. The study was conducted in Tanjung Benoa waters that covering three parts of the coast such as Samuh, Conrad and Tanjung beach in February until March 2017. Thalassia hemprichii leaves growth is observed consist of long and heavy growth (dry weight) and measured leaf age that has been observed such as young, half old and old leaves. The method that used to measure the growth of Thalassia hemprichii is pruning method and determination the research location using purposive sampling method. The aim of this research is explained the growth rate, biomass, and productivity of young leaves, old leaves of Thalassia hemprichii in Tanjung Benoa Bali. Measurement results of Thalassia hemprichii growth between age group of leaves has different young leaves faster growth if compared with the half old leaves and old leaves with average growth is 3.41mm/day indicates that the efficiency of this seagrass growth will decrease as the leaves age. The highest biomass values ??were found in older leaves if compared with young leaves and half-old leaves with average 0.205 gbk/m2 expected because the thick and wide leaf size will produced larger leaf biomass. The highest productivity value is found in oldest leaves in each station with average 0.028 gbk/m2/day expected morphology and different nutrient content in each leaf tissue.

Download Full-text

Effects of Soil pH on Competitive Ability and Leaf Nutrient Content of Corn (Zea maysL.) and Three Weed Species

Weed Science ◽

10.1017/s0043174500082631 ◽

1985 ◽

Vol 33 (4) ◽

pp. 447-451 ◽

Cited By ~ 24

Author(s):

Susan E. Weaver ◽

Allan S. Hamill

Keyword(s):

Soil Ph ◽

Competitive Ability ◽

Leaf Tissue ◽

Dry Weight ◽

Nutrient Content ◽

Setaria Viridis ◽

Weed Species ◽

Field Corn ◽

Green Foxtail ◽

Companion Plant

Effects of soil pH on growth, competitive ability, and leaf nutrient content of corn (Zea maysL.), Powell amaranth (Amaranthus powelliiS. Wats. ♯ AMAPO), velvetleaf (Abutilon theophrastiMedic. ♯ ABUTH), and green foxtail [Setaria viridis(L.) Beauv. ♯ SETVI] were measured in the field. Corn yields were significantly reduced by weed competition at all pH levels, but leaf nutrient content, as a percentage of dry weight, was not affected. Aboveground dry weights of Powell amaranth and velvetleaf were significantly lower at pH 4.8 than at pH 6.0 or 7.3, whereas growth of green foxtail was greater at pH 4.8 than at pH 7.3. Weed competitive ability, as evidenced by reductions in dry weight, varied with soil pH and companion plant. Powell amaranth and velvetleaf had higher levels of S, Zn, and especially Mn, at pH 4.8 than at pH 7.3. N and K in the leaf tissue were greater in the weed species than in corn at all soil pH levels. The dicot species had higher percentages of Ca and Mg in leaf tissue at all soil pH levels and accumulated higher percentages of Mn at low pH than the monocot species.

Download Full-text

A greater relative growth rate of Brassica rapa L. at low temperatures increases biomass at anthesis

Australian Journal of Agricultural Research ◽

10.1071/ar99031 ◽

2001 ◽

Vol 52 (6) ◽

pp. 645 ◽

Cited By ~ 3

Author(s):

P. Si ◽

N. Thurling

Keyword(s):

Growth Rate ◽

Brassica Rapa ◽

Seed Yield ◽

Negative Correlation ◽

Low Temperatures ◽

Leaf Tissue ◽

Dry Weight ◽

Controlled Environment ◽

Relative Growth ◽

Potassium Leakage

0t, n.s.). These relationships suggested that it might be possible to develop early flowering cultivars with increased seed yield by selecting for higher RGR before anthesis. RGR of BC 2 F 3:4 lines in the field during winter was correlated with RGR at low temperatures (13/4°C) in a controlled environment, suggesting that genotypes producing more dry weight at anthesis grew more at the low temperatures normally experienced in the field. This was supported by a significant (P < 0.05 0.05) negative correlation (r = –0.69**) between growth in the field and potassium leakage from leaf tissue at 4

Download Full-text

Leaf Age as a Risk Factor in Contamination of Lettuce with Escherichia coli O157:H7 and Salmonella enterica

Applied and Environmental Microbiology ◽

10.1128/aem.02459-07 ◽

2008 ◽

Vol 74 (8) ◽

pp. 2298-2306 ◽

Cited By ~ 148

Author(s):

M. T. Brandl ◽

R. Amundson

Keyword(s):

Escherichia Coli ◽

Population Size ◽

Salmonella Enterica ◽

Leaf Age ◽

Free Water ◽

Leaf Tissue ◽

E Coli ◽

Middle Leaf ◽

Young Leaves ◽

Population Sizes

ABSTRACT Outbreaks of Escherichia coli O157:H7 infections have been linked increasingly to leafy greens, particularly to lettuce. We present here the first evidence that this enteric pathogen can multiply on the leaves of romaine lettuce plants. The increases in population size of E. coli O157:H7 in the phyllosphere of young lettuce plants ranged from 16- to 100-fold under conditions of warm temperature and the presence of free water on the leaves and varied significantly with leaf age. The population size was consistently ca. 10-fold higher on the young (inner) leaves than on the middle leaves. The growth rates of Salmonella enterica and of the natural bacterial microflora were similarly leaf age dependent. Both enteric pathogens also achieved higher population sizes on young leaves than on middle leaves harvested from mature lettuce heads, suggesting that leaf age affects preharvest as well as postharvest colonization. Elemental analysis of the exudates collected from the surfaces of leaves of different ages revealed that young-leaf exudates were 2.9 and 1.5 times richer in total nitrogen and carbon, respectively, than middle-leaf exudates. This trend mirrored the nitrogen and carbon content of the leaf tissue. Application of ammonium nitrate, but not glucose, to middle leaves enhanced the growth of E. coli O157:H7 significantly, suggesting that low nitrogen limits its growth on these leaves. Our results indicate that leaf age and nitrogen content contribute to shaping the bacterial communities of preharvest and postharvest lettuce and that young lettuce leaves may be associated with a greater risk of contamination with E. coli O157:H7.

Download Full-text

The Impact of Phloem Feeding Insects on Leaf Ecophysiology Varies With Leaf Age

Frontiers in Plant Science ◽

10.3389/fpls.2021.625689 ◽

2021 ◽

Vol 12 ◽

Author(s):

Sylvain Pincebourde ◽

Jérôme Ngao

Keyword(s):

Growth Rate ◽

Stomatal Conductance ◽

Gas Exchange ◽

Carbon Content ◽

Nitrogen Content ◽

Leaf Gas Exchange ◽

Leaf Age ◽

Leaf Nitrogen Content ◽

Gas Exchanges ◽

Young Leaves

Herbivore insects have strong impacts on leaf gas exchange when feeding on the plant. Leaf age also drives leaf gas exchanges but the interaction of leaf age and phloem herbivory has been largely underexplored. We investigated the amplitude and direction of herbivore impact on leaf gas exchange across a wide range of leaf age in the apple tree–apple green aphid (Aphis pomi) system. We measured the gas exchange (assimilation and transpiration rates, stomatal conductance and internal CO2 concentration) of leaves infested versus non-infested by the aphid across leaf age. For very young leaves up to 15 days-old, the gas exchange rates of infested leaves were similar to those of non-infested leaves. After few days, photosynthesis, stomatal conductance and transpiration rate increased in infested leaves up to about the age of 30 days, and gradually decreased after that age. By contrast, gas exchanges in non-infested leaves gradually decreased across leaf age such that they were always lower than in infested leaves. Aphids were observed on relatively young leaves up to 25 days and despite the positive effect on leaf photosynthesis and leaf performance, their presence negatively affected the growth rate of apple seedlings. Indeed, aphids decreased leaf dry mass, leaf surface, and leaf carbon content except in old leaves. By contrast, aphids induced an increase in leaf nitrogen content and the deviation relative to non-infested leaves increased with leaf age. Overall, the impacts of aphids at multiple levels of plant performance depend on leaf age. While aphids cause an increase in some leaf traits (gas exchanges and nitrogen content), they also depress others (plant growth rate and carbon content). The balance between those effects, as modulated by leaf age, may be the key for herbivory mitigation in plants.

Download Full-text

Oviposition by the vagrant eriophyoid mite Aculops allotrichus on leaves of black locust tree, Robinia pseudoacacia

Experimental and Applied Acarology ◽

10.1007/s10493-019-00412-1 ◽

2019 ◽

Vol 79 (1) ◽

pp. 1-19

Author(s):

Katarzyna Michalska ◽

Anna Tomczyk ◽

Barbara Łotocka ◽

Sławomir Orzechowski ◽

Marcin Studnicki

Keyword(s):

Cell Walls ◽

Black Locust ◽

Robinia Pseudoacacia ◽

Leaf Age ◽

Leaf Tissue ◽

Adaxial Side ◽

Abaxial Side ◽

Production And Distribution ◽

Young Leaves ◽

Eriophyoid Mite

Abstract Leaf-dwelling mites often prefer to feed on young leaves and also are more likely to inhabit the abaxial leaf side. The aim of our study was to examine whether leaf age may affect production and distribution of eggs on black locust leaves by females of Aculops allotrichus. The eriophyoids were tested for 2.5 days on ‘trimmed’ compound leaves (with only two opposite leaflets left), which were maintained in vials filled with water. For the experiments we used leaves of three categories: (1) the ‘youngest’, in which both halves of the adaxial side of leaflets still adhered to each other (and usually remained folded for the next few hours), (2) ‘young’ with already unfolded leaflets, and (3) ‘mature’ with fully expanded leaflets. The tested females laid significantly more eggs on developing leaves than on ‘mature’ ones, although they deposited the highest number of eggs on the ‘young’ leaves. The distribution of eggs on adaxial or abaxial leaf sides also depended on leaf age. On the ‘youngest’ leaves, eriophyoids placed similar numbers of eggs on both sides of a blade. However, the older the leaf, the more willingly females deposited eggs on the abaxial side. Our biochemical and morphometrical analyses of black locust leaves indicated significant changes in the contents of nutrients and phenols within leaf tissue, and in the density of trichomes and thickness of the outer epidermal cell walls, correlated with leaf age. Their possible effects on the production and distribution of eggs on leaves by A. allotrichus are discussed.

Download Full-text

Nutrient sufficiency levels for haskap (Lonicera caeruleaL.) using the boundary-line approach

Canadian Journal of Plant Science ◽

10.1139/cjps-2018-0151 ◽

2019 ◽

Vol 99 (2) ◽

pp. 268-280 ◽

Cited By ~ 1

Author(s):

Ekene Mark-Anthony Iheshiulo ◽

Lord Abbey ◽

Andrew M. Hammermeister

Keyword(s):

Growth Rate ◽

Nova Scotia ◽

Leaf Tissue ◽

Principal Component ◽

Leaf Size ◽

Nutrient Status ◽

Boundary Line ◽

Tissue Samples ◽

Leaf Tissues ◽

Representative Farms

Adequate supply of plant nutrients is crucial for haskap plant growth and increased productivity. A study was carried out to determine the variability in haskap (Lonicera caerulea L. cv. Indigo Gem) plant characteristics in relation to soil and leaf tissue nutrient status. A total of 19 composite soil samples and corresponding plant leaf tissue samples were collected in 2016 from 12 locations in Nova Scotia. Plant parameters measured include growth rate, leaf size, leaf chlorophyll content, and visual observations. A boundary-line approach was used to determine nutrient sufficiency ranges in leaf tissues of 2.23%–2.96% for N, 0.22%–0.28% for P, 0.84%–1.32% for K, 1.63%–2.10% for Ca, and 0.14%–0.50% for Mg. Principal component and correlation analysis suggested a possible antagonistic interaction between leaf K and Mg. Negative associations were observed most frequently between Ca and Mg and other nutrients, especially K. Plant parameters such as bush volume, leaf size, and growth rate were closely related to soil and leaf K. Deficiencies in leaf tissue K and P were identified as potentially important factors limiting growth. Therefore, there is a need to adjust or balance the application of these nutrients. In conclusion, the sufficiency ranges derived can be used as a guiding principle in diagnosing the nutritional status of haskap cv. Indigo Gem on representative farms in Nova Scotia.

Download Full-text

Distribution of Elements along the Rachis of Cycas micronesica Leaves: A Cautionary Note for Sampling Design

Horticulturae ◽

10.3390/horticulturae5020033 ◽

2019 ◽

Vol 5 (2) ◽

pp. 33 ◽

Cited By ~ 5

Author(s):

Thomas E. Marler ◽

Murukesan V. Krishnapillai

Keyword(s):

Elemental Concentration ◽

Leaf Age ◽

Leaf Tissue ◽

Nutrient Concentrations ◽

Tissue Analysis ◽

Sampling Protocols ◽

Distribution Of Elements ◽

Young Leaves ◽

The Difference ◽

Nitrogen Phosphorus

Cycas micronesica K.D. Hill trees on the island of Yap were used to determine the influence of position along the leaf rachis on macro- and micro-nutrient concentrations and how leaf age affected the results. The outcomes revealed improvements to sampling protocols for future cycad leaf research. The concentration of every element except carbon and copper was influenced by leaflet position along the rachis. Most elements exhibited similar patterns for the oldest and youngest leaves on a tree, but the influence of position along the rachis for nitrogen, phosphorus, calcium, zinc, and boron was highly contrasting for old versus young leaves. The elements with the greatest variability along the rachis were potassium, phosphorus, manganese, and zinc, with the difference in basal and terminal leaflets as great as four-fold. Sampling leaflets at one position on a cycad leaf may generate inaccurate elemental concentration results for most essential nutrients other than carbon and copper. We have added position of sampled leaflets within leaves as a mandatory component of what is recorded and reported for future cycad leaf tissue analyses. Leaflets that span the full length of the rachis should be included in cycad leaf samples that are collected for tissue analysis.

Download Full-text

INDUCCIÓN DE LA PRODUCCIÓN DE LÍPIDOS TOTALES EN MICROALGAS SOMETIDAS A ESTRÉS NUTRITIVO

Acta Biológica Colombiana ◽

10.15446/abc.v21n1.47439 ◽

2015 ◽

Vol 21 (1) ◽

Cited By ~ 3

Author(s):

Marianela Cobos Ruiz ◽

Jae Diana Paredes Rodríguez ◽

Juan Carlos Castro Gómez

Keyword(s):

Growth Rate ◽

Dry Weight ◽

Culture Conditions ◽

Scenedesmus Quadricauda ◽

Total Biomass ◽

Total Lipids ◽

Average Growth ◽

Chlorella Sp ◽

Dry Biomass ◽

Chloroform Methanol

RESUMENSe evaluó la producción de lípidos totales en cinco especies de microalgas inducidas por la ausencia de nitrógeno. Las microalgas empleadas fueron Ankistrodesmus sp., Ankistrodesmus nannoselene, Chlorella sp., Scenedesmus sp. y Scenedesmus quadricauda. Estas especies fueron cultivadas en medio CHU10 con y sin nitrógeno. El tiempo de evaluación fue de seis días, determinándose diariamente la densidad microalgal mediante recuento en cámara de Neubahuer. Se determinó la tasa de crecimiento, la biomasa microalgal y el porcentaje de lípidos totales. Los lípidos totales fueron extraídos con solución Cloroformo:metanol (2:1). Los resultados indicaron que las especies con mayor producción de lípidos totales fueron Ankistrodesmus sp. (263,6 mg/g biomasa seca), A. nannoselene (316 mg/g biomasa seca) y Scenedesmus sp. (243,3 mg/g biomasa seca) al ser cultivadas en medios sin nitrógeno. Scenedesmus quadricauda y Chlorella sp., fueron las especies que mostraron mayor producción de biomasa seca (159,1 mg/g biomasa seca y 221,1 mg/g biomasa seca respectivamente) en medios con nitrógeno. La tasa de crecimiento fue variable entre las especies cultivadas en ambas condiciones. En conclusión, Ankistrodesmus sp., mostró la mayor tasa de crecimiento (0,77 dia-1) en medio sin nitrógeno. Bajo las mismas condiciones de cultivo, Scenedesmus sp. obtuvo la mayor producción de biomasa en peso seco (174,7 mg/l) y Ankistrodesmus nannoselene acumuló el mayor porcentaje de lípidos totales.ABSTRACTThe production of total lipids in five microalgal species was induced by absence of nitrogen. The microalgae Ankistrodesmus sp., Ankistrodesmus nannoselene, Chlorella sp., Scenedesmus sp. and Scenedesmus quadricauda were cultured in CHU10 medium with and without nitrogen. They were evaluated during six days. The microalgae density was daily determined by a Neubahuer chamber. The average growth, total biomass and total lipids were also determined. The total lipids were extracted with chloroform: methanol (2:1). The results indicated that species with production greater amount of total lipids were Ankistrodesmus sp. (263.6 mg/g dry biomass), Ankistrodesmus nannoselene (316 mg/g dry biomass) and Scenedesmus sp. (243.3 mg/g dry biomass) when grown in media without nitrogen. Scenedesmus quadricauda and Chlorella sp. when grown in media with nitrogen showed higher amount of dry biomass (159.1 mg/g dry biomass and 221.1 mg/g dry biomass respectively) compared to those which were grown in media without nitrogen. The growth rate was variable between species grown in both conditions. In conclusion, Ankistrodesmus sp. microalgae experienced the highest growth rate (0.77 day-1) in medium without nitrogen. Under the same culture conditions, Scenedesmus sp., had the highest biomass production in dry weight (174.7 mg/l) and Ankistrodesmus nannoselene accumulated the highest percentage of total lipids.

Download Full-text

Effect of Seed Mass on Germination and Seedling Vigour of Parkia Timoriana (DC.) Merr.

Current Agriculture Research Journal ◽

10.12944/carj.4.2.06 ◽

2016 ◽

Vol 4 (2) ◽

pp. 171-178 ◽

Cited By ~ 1

Author(s):

Uttam Thangjam ◽

U. K Sahoo

Keyword(s):

Growth Rate ◽

Seed Weight ◽

Growth Parameters ◽

Seed Mass ◽

Dry Weight ◽

Garden Soil ◽

Weight Class ◽

Seedling Vigour ◽

Average Growth ◽

Seedling Length

Seeds of Parkia tiamoriana show both intra specific and inter specific variation in seed weight. A research was carried out to study the effect of seed mass on germination and early growth parameters of the species. Mature seeds were collected from Sakawrtuchung provenance of Mizoram (India). They were then bulked and grouped into 3 categories as light (lwt), intermediate (mwt) and heavy (hwt), using a predetermines weight method. The grouped seeds are then sown using 1mm sieved garden soil as a medium in poly bags. After germination and from the two leave stage we start counting the seedling length, collar diameter, dry weight, etc., at every 15 days interval and up to 90th day, by using destructive method. Study on the germination and seedling growth parameters conclude that except in mean germination time (MGT) and germination index (GI), all the other parameters are positively correlated with increasing weight. Relative growth rate (RGR) and average growth rate (AGR) that use seedling dry weight also showed a positive relation with seed weight. Apart from this, the distribution pattern of seed weights as calculated from the frequency distribution of 255 seeds did not show lognormal distribution (K-S test: P<0.05, d = 0.163, n = 255). Seed weight (n=255) varied from 0.39g to 0.81g (mean: 0.61g ± 0.01g). Among the weight class, mid weight (0.5 to 0.69g) seeds made up 56.47% of the total population followed by heavy weight (23.14%) and then by light weight (20.39%).

Download Full-text

SHOOT GROWTH AND DEVELOPMENT OF `STARKSPUR SUPREME DELICIOUS' VARIES WITH ROOTSTOCK.

HortScience ◽

10.21273/hortsci.25.9.1111f ◽

1990 ◽

Vol 25 (9) ◽

pp. 1111f-1111

Author(s):

Curt R. Rom

Keyword(s):

Growth Rate ◽

Leaf Area ◽

Shoot Growth ◽

Leaf Size ◽

Dry Weight ◽

Shoot Length ◽

Internode Length ◽

Terminal Bud ◽

Shoot Growth Rate ◽

Old Trees

Shoot growth `Starkspur Supreme Delirious' on 10 different rootstock was measured on 3-, 4- and 6-year-old trees at weekly intervals from budbreak until terminal bud formation. Spur density, spur development, and extension shoot leaf area development were measured in September. Growth rate was analyzed by regression against chronological time and accumulated growing degree days using linear and nonlinear statistics.Rootstock affected shoot length, leaf number, leaf area, leaf size, leaf dry weight/leaf area and internode length. Trees on M.4, M.7 EMLA, P-1 and seedling had the longest shoots and highest shoot growth rate. Trees on P16 had least leaves and leaf area per shoot and smallest shoot leaves. Leaf dry wt./area were negatively correlated to leaf size. Typically, trees with shortest shoot length and smallest internode length had greatest spur density. Rootstock affected both rate and duration of shoot growth. Shoots on trees with P22 and P2 rootstocks grew for the shortest duration while trees on M.4 and M.7 EMLA grew for the longest period.

Download Full-text