Changes in Some Carbohydrate Fractions and Some Related Enzymic Activities in Plump and Shrivelled Triticale and in Wheat Grains

1986 ◽  
Vol 13 (2) ◽  
pp. 249 ◽  
Author(s):  
AS Dhaliwal ◽  
HL Sharma
Keyword(s):  
Starch Content ◽  
Soluble Sugars ◽  
Grain Filling ◽  
Starch Synthase ◽  
Starch Phosphorylase ◽  
Total Soluble Sugars ◽  
Final Maturation ◽  
Triticale Line ◽  
Grain Filling Period ◽  
Developing Grains

Activities of α-amylase (EC 3.2.1.1), β-amylase (EC 3.2.1.2), soluble ADPglucose-starch synthase (EC 2.4.1.21), starch phosphorylase (EC 2.4.1.1), sucrose synthase (EC 2.4.1.13) and invertase (EC 3.2.1.26), and amounts of reducing sugars, total soluble sugars and starch, were studied in the developing grains of wheat and triticale lines. A triticale line (TL1) with shrivelled grains contained a low starch content, increased reducing and total soluble sugars during the final grain-filling period as well as a higher moisture at maturity than wheat and a plump-grain triticale line (TL2). The overall activities of soluble ADPglucose-starch synthase and starch phosphorylase remained lower and that of α- and β-amylases higher in TL1 than wheat and TL2 throughout grain development. The higher amylolytic activity retained during the final maturation period appears to be at least partly due to the higher moisture content of the grain in the triticale line TL1 with shrivelled grains.

Effects of low temperature on grain filling, amylose content, and activity of starch biosynthesis enzymes in endosperm of basmati rice

2008 ◽  
Vol 59 (7) ◽  
pp. 599 ◽  
Author(s):  
Nisar Ahmed ◽  
Masahiko Maekawa ◽  
Ian J. Tetlow
Keyword(s):  
Low Temperature ◽  
Amylose Content ◽  
Oryza Sativa L ◽  
Starch Content ◽  
Grain Filling ◽  
Soluble Starch ◽  
Starch Biosynthesis ◽  
Starch Synthase ◽  
Basmati Rice ◽  
Starch Phosphorylase

The effects of low temperature on amylose contents and activities of key enzymes related to starch biosynthesis in basmati rice (Oryza sativa L.) endosperm were investigated. Low temperature treatment prolonged the grain-filling period from 32 days to 53 days, but had no significant effect on the final grain weight. Results showed that low temperature during grain filling had no significant effect on total starch content but increased the amylose content in the mature endosperm of hulled rice by 21%. The measurable activities of sucrose synthase (SuSy), ADP-glucose pyrophosphorylase (AGPase), starch phosphorylase (SPase), starch branching enzyme (SBE), and soluble starch synthase (SS) in endosperms developed at 12°C were lower than those at 22°C when compared at a similar ripening stage on an endosperm basis, but the activity of granule-bound starch synthase (GBSS) was significantly higher than the corresponding activity in endosperms developing at 22°C. These findings suggest that GBSS might play a crucial role in increasing amylose during low-temperature growth conditions.

Reduced Starch Content and Sucrose Synthase Activity in Developing Endosperm of Barley Plants Grown at Elevated Temperatures

1988 ◽  
Vol 15 (3) ◽  
pp. 367 ◽  
Author(s):  
LC MacLeod ◽  
CM Duffus
Keyword(s):  
Elevated Temperatures ◽  
Starch Content ◽  
Grain Filling ◽  
Starch Accumulation ◽  
Grain Development ◽  
Irreversible Reduction ◽  
Short Period ◽  
Cleavage Enzyme ◽  
Grain Filling Period ◽  
Sucrose Cleavage

Starch accumulation is reduced when endosperms develop at elevated temperatures. Reduced starch deposition does not appear to be due to limiting assimilate levels during the grain filling period; on the contrary, endosperm sucrose may even be increased at the elevated temperature. Results indicate that elevated temperatures significantly reduce the activity of the sucrose cleavage enzyme UDPsucrose synthase (EC 2.4.1.13), found in the endosperm during grain development, and that these effects may be initiated by a relatively short period of thermal stress applied close to anthesis. It would appear that, when developing barley ears are exposed to elevated temperatures, there is an irreversible reduction in the capacity of the endosperm to convert sucrose to starch, caused by a decrease in the activity of at least one of the enzymes involved in this conversion pathway.

Starch content and activities of starch-metabolizing enzymes in effective and ineffective root nodules of soybean

1991 ◽  
Vol 69 (4) ◽  
pp. 697-701 ◽  
Author(s):  
Sharon I. Forrest ◽  
Desh Pal S. Verma ◽  
Rajinder S. Dhindsa
Keyword(s):  
Nitrogen Fixation ◽  
Starch Content ◽  
Root Nodules ◽  
Starch Synthase ◽  
Nodule Development ◽  
Wild Type ◽  
Starch Phosphorylase ◽  
High Concentration ◽  
Key Words Nitrogen Fixation ◽  
Glycine Max L

Starch content and activities of some enzymes of starch metabolism were determined in wild-type, N2-fixing (fix+) nodules and in two non-N2-fixing (fix−) nodules induced by Bradyrhizobium japonicum mutant strains, T5-95 and T8-1, on soybean (Glycine max L.) roots. The T5-95 nodules are similar to wild type in ultrastructure, but the T8-1 nodules are different in that the bacteroids are not released from the infection thread. After initial accumulation to relatively high concentration, starch was depleted during nitrogen fixation in fix+ nodules. However, in fix− nodules, the accumulated starch was not metabolized. The activity of starch-bound starch synthase (EC 2.4.1.21) declined in fix+ nodules but remained high in fix− nodules. The activity of α-amylase (EC 3.2.1.1) was only slightly higher than wild type in T5-95 but was four times higher than wild type in T8-1 nodules. The activity of starch phosphorylase (EC 2.4.1.1) increased in all nodule types from 14 to 21 days postinfection. A positive correlation was observed between the capacity of nodules to fix N2 and their capacity to degrade starch. Collectively, these results support the concept that starch accumulated during early stages of nodule development is metabolized to supply energy for nitrogen fixation and to meet the metabolic demands of bacteroids. Key words: nitrogen fixation, starch content, effective and ineffective nodules, starch synthase, starch phosphorylase, α-amylase.

scholarly journals Comparative Physiology of Natural Deacclimation in Ten Azalea Cultivars

HortScience ◽  
2017 ◽  
Vol 52 (10) ◽  
pp. 1451-1457 ◽  
Author(s):  
Bing Liu ◽  
Hong Zhou ◽  
Sha Cao ◽  
Yi-ping Xia ◽  
Rajeev Arora
Keyword(s):  
Freezing Tolerance ◽  
Starch Content ◽  
Eastern China ◽  
Soluble Sugars ◽  
Comparative Physiology ◽  
Natural Conditions ◽  
Total Soluble Sugars ◽  
Opposite Trend ◽  
Mean Temperature

Seasonal deacclimation was investigated during Jan. to Mar. 2014 in leaves of 10 azalea cultivars (Rhododendron section Tsutsusi) under natural conditions in eastern China. Based on the midwinter leaf freezing tolerance (LFT), these cultivars were grouped as “more-hardy” vs. “less-hardy.” Eight of the 10 cultivars first showed deacclimation when daily mean temperature over 2-week period preceding the LFT measurement was ≈9.5 °C. Deacclimation for other two cultivars was somewhat delayed and might have involved deacclimation–reacclimation cycling before eventual deacclimation. Our data indicate that the “more-hardy” group deacclimated slower than the “less-hardy” ones over the first half of the deacclimation period. This trend reversed during the second half of the deacclimation period. Accordingly, “more-hardy” and “less-hardy” cultivars depicted a “curvilinear” and “reverse curvilinear/linear” deacclimation kinetics. “More-hardy” cultivars generally had higher total soluble sugars (TSS) than “less-hardy” ones at acclimated state. TSS declined during deacclimation in all cultivars, and the loss was positively correlated with the loss in LFT. Leaf starch content generally followed opposite trend to that of TSS, i.e., it was at lowest during acclimated state and increased during deacclimation.

scholarly journals QUALITY OF TABLE CASSAVA ROOTS FERTILIZED WITH PHOSPHORUS1

2021 ◽  
Vol 34 (4) ◽  
pp. 965-975
Author(s):  
FLÁVIO PEREIRA DA MOTA SILVEIRA ◽  
WELDER DE ARAÚJO RANGEL LOPES ◽  
PEDRO RAMON HOLANDA DE OLIVEIRA ◽  
FERNANDA LARISSE DOS SANTOS LIMA ◽  
LINDOMAR MARIA DA SILVEIRA ◽  
...  
Keyword(s):  
Starch Content ◽  
Abiotic Factors ◽  
Soluble Sugars ◽  
Titratable Acidity ◽  
Quality Parameters ◽  
Cooking Time ◽  
Soluble Solids ◽  
Total Soluble Sugars ◽  
Brazilian Semiarid

ABSTRACT The quality parameters of cassava roots vary between cultivars and depend on abiotic factors, such as plant nutrition. However, the magnitude of how these factors interfere is not yet well defined, especially for phosphorus (P), which is a nutrient directly linked to the synthesis of sugars and starches in plants. Thus, the objective of the research was to evaluate the quality of roots of table cassava cultivars fertilized with doses of P in the Brazilian semiarid. The research was carried out at the Rafael Fernandes experimental farm, Mossoró, RN, Brazil, from June 2018 to April 2019. The experimental design used was in randomized blocks, arranged in subdivided plots and with four replications. Doses of P (0, 60, 120, 180 and 240 kg ha-1 of P2O5) were applied in the plots, and in the subplots, the table cassava cultivars (Água Morna, BRS Gema de Ovo, Recife and Venâncio). Firmness, elasticity, titratable acidity, soluble solids, total soluble sugars, starch and cooking were all evaluated. The quality of table cassava roots varied depending on the cultivar and the dose of P. Doses of P between 120 and 240 kg ha-1 of P2O5 increase the starch content and reduce the cooking time of table cassava roots.

scholarly journals Dynamic Changes in Starch Metabolism and Endogenous Hormones during Stolon Formation in Tulipa edulis

2016 ◽  
Vol 141 (3) ◽  
pp. 211-221 ◽  
Author(s):  
Yuanyuan Miao ◽  
Qiaosheng Guo ◽  
Zaibiao Zhu ◽  
Xiaohua Yang ◽  
Changlin Wang ◽  
...  
Keyword(s):  
Starch Content ◽  
Initial Period ◽  
Soluble Sugar ◽  
Soluble Sugars ◽  
Sucrose Phosphate Synthase ◽  
Starch Synthase ◽  
Endogenous Hormones ◽  
Dynamic Changes ◽  
Total Soluble Sugar ◽  
Middle Period

The stolon is the main asexual reproductive organ of the medicinal plant Tulipa edulis and has special morphology. In the greenhouse experiment presented herein, the dynamic changes in carbohydrates and related enzymes, proteins, and endogenous hormones of stolons during T. edulis stolon formation were investigated. The results showed that the content of total soluble sugar, sucrose, reducing sugar, fructose, and starch were all significantly enhanced in the middle period when stolon emerged and maintained at relatively high levels until the later period of stolon formation, while protein content decreased during stolon formation. The activities of amylase (AMY), sucrose phosphate synthase (SPS), and sucrose synthase (SS) peaked in the initial period and were negatively correlated with soluble sugars. However, adenosine diphosphoglucose pyrophosphorylase (AGPase) activity increased as stolon formation progressed, and the changes in soluble starch synthase (SSS), granule-bound starch synthase (GBSS) activities presented a single peak, reaching their maximums in the middle period. AGPase, SSS, and GBSS activities were all positively related to starch content. Moreover, quantitative real-time polymerase chain reaction (qRT-PCR) verified the changes in SS and SSS activities via the expression levels of the SS, SSSI, and SSSII genes. The gibberellin (GA) and zeatin riboside (ZR) content attained their maximum in the initial period of stolon formation. Indole-3-acetic acid (IAA) and abscisic acid (ABA) remained at high levels during the initial and middle period and decreased significantly during the later period of stolon formation, inversely to the ratio of ABA:IAA. Analysis of the physiological changes in T. edulis stolon indicated that the accumulation of soluble sugars and starch via various enzymes, a high level of IAA and a low ABA to IAA ratio mainly contributed to stolon development of T. edulis. This paper explored carbohydrate levels and endogenous hormones profiles during stolon formation, which provided the theory basis for further regulating stolon growth of T. edulis.

scholarly journals Bioinformatic and experimental evidence for suicidal and catalytic plant THI4s

2020 ◽  
Vol 477 (11) ◽  
pp. 2055-2069 ◽  
Author(s):  
Jaya Joshi ◽  
Guillaume A.W. Beaudoin ◽  
Jenelle A. Patterson ◽  
Jorge D. García-García ◽  
Catherine E. Belisle ◽  
...  
Keyword(s):  
Active Site ◽  
De Novo ◽  
Indirect Evidence ◽  
Grain Filling ◽  
Prima Facie ◽  
Major Type ◽  
In Planta ◽  
Prima Facie Case ◽  
Grain Filling Period ◽  
Developing Grains

Like fungi and some prokaryotes, plants use a thiazole synthase (THI4) to make the thiazole precursor of thiamin. Fungal THI4s are suicide enzymes that destroy an essential active-site Cys residue to obtain the sulfur atom needed for thiazole formation. In contrast, certain prokaryotic THI4s have no active-site Cys, use sulfide as sulfur donor, and are truly catalytic. The presence of a conserved active-site Cys in plant THI4s and other indirect evidence implies that they are suicidal. To confirm this, we complemented the Arabidopsistz-1 mutant, which lacks THI4 activity, with a His-tagged Arabidopsis THI4 construct. LC–MS analysis of tryptic peptides of the THI4 extracted from leaves showed that the active-site Cys was predominantly in desulfurated form, consistent with THI4 having a suicide mechanism in planta. Unexpectedly, transcriptome data mining and deep proteome profiling showed that barley, wheat, and oat have both a widely expressed canonical THI4 with an active-site Cys, and a THI4-like paralog (non-Cys THI4) that has no active-site Cys and is the major type of THI4 in developing grains. Transcriptomic evidence also indicated that barley, wheat, and oat grains synthesize thiamin de novo, implying that their non-Cys THI4s synthesize thiazole. Structure modeling supported this inference, as did demonstration that non-Cys THI4s have significant capacity to complement thiazole auxotrophy in Escherichia coli. There is thus a prima facie case that non-Cys cereal THI4s, like their prokaryotic counterparts, are catalytic thiazole synthases. Bioenergetic calculations show that, relative to suicide THI4s, such enzymes could save substantial energy during the grain-filling period.

scholarly journals The Effects of Short-Term Exposure to Low Temperatures During the Booting Stage on Starch Synthesis and Yields in Wheat Grain

2021 ◽  
Vol 12 ◽  
Author(s):  
Wenjing Zhang ◽  
Yan Zhao ◽  
Lingyu Li ◽  
Xu Xu ◽  
Li Yang ◽  
...  
Keyword(s):  
Low Temperatures ◽  
Dry Matter ◽  
Starch Content ◽  
Starch Synthesis ◽  
Grain Filling ◽  
Starch Synthase ◽  
Wheat Grain ◽  
Short Term ◽  
Booting Stage ◽  
Grain Starch

Low temperatures (LT) in spring can have a major impact on the yields of wheat in winter. Wheat varieties with different cold sensitivities (the cold-tolerant Yannong 19 variety and the cold-sensitive Yangmai 18 variety) were used to study the responses of the wheat grain starch synthesis and dry material accumulation to short-term LT during the booting stage. The effects of short-term LT on the activities of key wheat grain starch synthesis enzymes, starch content and grain dry-matter accumulation were determined by exposing the wheat to simulated LT of from −2 to 2°C. Short-term LT stress caused a decrease in the fullness of the wheat grains along with decreased activities of adenosine diphosphate glucose pyrophosphorylase (AGPase, EC2.7.7.27), soluble starch synthase (SSS, EC2.4.1.21), granule-bound starch synthase (GBSS, EC2.4.1.21), and starch branching enzyme (SBE, EC2.4.1.18) at different spike positions during the filling stage. The rate of grain starch accumulation and starch content decreased with decreasing temperatures. Also, the duration of grain filling increased, the mean and the maximum filling rates were reduced and the quality of the grain dry-matter decreased. The number of grains per spike and the thousand-grain weight of the mature grains also decreased. Our data showed that short-term LT stress at the booting stage caused a decrease in the activities of key starch synthesis enzymes at the grain-filling stage. These changes reduced the accumulation of starch, decreased the filling rate, and lowered the accumulation of grain dry matter to ultimately decrease grain yields.

The effect of sample date and plant density on the carbohydrate content of forage maize and the changes that occur on ensiling

1977 ◽  
Vol 89 (3) ◽  
pp. 589-597 ◽  
Author(s):  
A. B. McAllan ◽  
R. H. Phipps
Keyword(s):  
Plant Density ◽  
Starch Content ◽  
Sugar Content ◽  
Soluble Sugar ◽  
Soluble Sugars ◽  
Sampling Period ◽  
Dry Weight ◽  
Total Soluble Sugars ◽  
Forage Maize ◽  
Total Soluble Sugar

SummaryThe (early maturing) maize hybrid, Anjou 210, was sown on 1 May (1975) and 50000 (LD) and 150000 (HD) plants/ha established. Leaf, stem, ear and husk components of the shoots, and whole shoots were separately examined for changes in dry weight, soluble sugars, starch, hemicellulose and cellulose at regular intervals from 104 to 154 days after planting together with whole shoots after ensiling.Throughout the sampling period whole shoot and ear dry weights increased steadily whereas those of leaf and stem decreased in plants from both treatments.Total soluble sugar contents for plants grown at LD were at a maximum 104 days after planting compared with 125 days after planting for the HD crop. Immediately prior to ensiling whole shoot soluble sugar content was 74 and 93 g/kg D.M. for LD and HD treatments respectively.Small amounts of starch (g/kg D.M.) were found in stems (10–25), husks (40–80) and leaves (17–35) of plants grown at both densities. The starch content of the ear increased from 57 to 390 g/kg D.M. and 168 to 376 g/kg D.M. in plants grown at LD and HD respectively.For plants from both treatments hemicellulose contents of husks, leaves and whole shoots increased with age whereas those of stems decreased. Cellulose contents did not vary greatly over the growing season.On ensiling plants from both densities, total soluble sugars had virtually disappeared after only 3 days. Apparent losses (approximately 0·3 g/g), over a longer period of time, were observed in hemicellulose sugars and starch. Apparent increases were observed in cellulose contents of approximately 0·15 g/g.

Effects of grain position on the panicle on starch biosynthetic enzyme activity in developing grains of rice cultivar Tainung 67 and its NaN3-induced mutant

2003 ◽  
Vol 141 (3-4) ◽  
pp. 303-311 ◽  
Author(s):  
T. L. JENG ◽  
C. S. WANG ◽  
C. L. CHEN ◽  
J. M. SUNG
Keyword(s):  
Enzyme Activities ◽  
Initial Period ◽  
Grain Filling ◽  
Rice Cultivar ◽  
Starch Biosynthesis ◽  
Starch Accumulation ◽  
Grain Filling Period ◽  
Starch Conversion ◽  
Developing Grains ◽  
Induced Mutant

The content of starch and the activities of enzymes involved in starch biosynthesis were examined in developing grains of field grown rice (Oryza sativa L.) plants. Enzyme activities were monitored throughout the grain filling period of cultivar Tainung 67 and its NaN3-induced mutant SA419. The activities of most of the grain enzymes involved in starch biosynthesis increased and reached their maxima during the initial period of grain development, then gradually declined towards the later stages of grain filling. Both Tainung 67 and SA419 showed different starch and amylose accumulation patterns in different grain positions. In cultivar Tainung 67, reduced activities of grain enzymes involved in starch biosynthesis, particularly during the early phase of grain filling, were related to the decreased starch accumulation for the grains located on proximal secondary branches as compared with the grains located on distal primary branches. The decreased amylose contents in the grains of Tainung 67 located on proximal secondary branches were attributable to their lower granule bound starch synthase and starch debranching enzyme activities at early and mid phases of grain filling. In mutant SA419, no significant changes were observed in the activities of grain enzymes involved in sucrose to starch conversion between the grains located on distal primary and proximal secondary branches of the panicle. As a result, grain setting position was found to have little effect on the contents of starch and amylose for these developing grains located on different branches. Thus, the mutant SA419 did have some agronomic and physiological traits that were superior to its wild type cultivar Tainung 67.

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