Photosynthesis and Partitioning of Dry Matter in Sunflower

1979 ◽  
Vol 6 (2) ◽  
pp. 149 ◽  
Author(s):  
SD English ◽  
JR Mcwilliam ◽  
RCG Smith ◽  
JL Davidson
Keyword(s):  
Dry Matter ◽  
Light Response ◽  
Dry Weight ◽  
Linear Increase ◽  
Main Stem ◽  
Exponential Relationship ◽  
Factors Affecting ◽  
Physiological Maturity ◽  
Order Of Magnitude ◽  
Controlled Environments

Environmental and plant factors affecting photosynthesis in sunflower were studied in controlled environments and under field conditions. The response to temperature had a broad optimum around 27°C indicating that temperature is unlikely to limit photosynthesis of the crop under normal summer growing conditions. As found for most crops, carbon dioxide was the main factor limiting photosynthesis under optimum conditions of temperature and irradiance. Photosynthetic rates varied with the age and position of the leaf on the main stem. The maximum rate achieved by any leaf was obtained by fitting an exponential relationship of the form P = A(l -e-BI), which gave an adequate description of the light response curve. The photosynthetic rate of leaves increased to a maximum just prior to full leaf expansion and then declined. An increasing rate of photosynthesis was also characteristic of the leaf profile up the main stem, culminating in highest rates in the upper part of the leaf canopy. These data indicate that the larger recently developed active leaves, which are produced on the upper part of the stem, have the greatest potential photosynthetic capacity and are most effective in supplying carbon assimilates at all stages during the development of the crop. In the field, rates of photosynthesis for individual leaves were of the same order of magnitude and followed the same pattern as those recorded in controlled environments. Also, their diurnal patterns of photosynthesis and stomatal conductance were relatively unaffected by reduced water potentials as low as -2.0 to -2.5 MPa during the middle of the day. The partitioning of dry matter in sunflower into the various above ground parts was characterized and at physiological maturity the seed represented 55% of the dry weight of the inflorescence but only 33% of the dry weight of the total plant. There was a linear increase with time in the oil content of the seed following fertilization, reaching a maximum at about 20-25 days, several weeks before the seed reached physiological maturity. These data can provide the necessary response functions required for the photosynthetic submodel of a more comprehensive model to predict the yield and adaptation of sunflower under varying environmental conditions.

Growth, Nodulation and Nitrogen Fixation in Stylosanthes: Effect of Different Root Temperatures at two Shoot Temperatures

1989 ◽  
Vol 25 (4) ◽  
pp. 447-460 ◽  
Author(s):  
R. A. Date ◽  
D. Ratcliff
Keyword(s):  
Nitrogen Fixation ◽  
Dry Matter ◽  
Maximum Yield ◽  
Dry Weight ◽  
Strong Interactions ◽  
Root Temperature ◽  
Relative Growth ◽  
Stylosanthes Hamata ◽  
Nitrogen Yields ◽  
Controlled Environments

SUMMARYNodulated plants of Stylosanthes hamata, S. guianensis, S. humilis, S. scabra and S. fruticosa were grown in controlled environments with varied root and shoot temperatures. Measurement of dry matter and nitrogen content suggested that shoot temperature may be more important than root temperature in controlling growth and nitrogen fixation. There were strong interactions with variety. A fall in relative growth rate with increase in shoot temperature was least for S. guianensis and greatest for S. hamata and S. scabra. The optimum root temperature for growth and nitrogen fixation was approximately 30°C. Ninety percent maximum yield was achieved between root temperatures of 15–36°C for growth and 23–34°C for nitrogen fixation but varied with variety. Nitrogen fixation was more sensitive than dry weight to root temperature. The pattern of response of percentage nitrogen and nitrogen fixation efficiency reflected those for dry weight and nitrogen yields. Shoot to root ratios decreased toward the optimum root temperature then increased at the highest temperature. The reaction of varieties to root and shoot temperatures may be an important factor in determining their suitability for new regions.

THE GROWTH PATTERN OF CORN IN RELATION TO RESISTANCE TO ROOT AND STALK ROT

1965 ◽  
Vol 43 (10) ◽  
pp. 1277-1283 ◽  
Author(s):  
R. E. Wall ◽  
C. G. Mortimore
Keyword(s):  
Growth Pattern ◽  
Dry Matter ◽  
Dry Weight ◽  
High Ratio ◽  
Vegetative Tissue ◽  
Physiological Maturity ◽  
Stalk Rot ◽  
Pith Tissue ◽  
Single Cross ◽  
Single Cross Hybrids

Single-cross hybrids resistant to root and stalk rot generally had greater growth rates, leaf areas, and stalk densities than susceptible single crosses. Differences in dry weight of tops were evident by the time of silk emergence and these differences became more pronounced as the hybrids approached maturity. Susceptible hybrids were characterized by a cessation of vegetative growth at pollination and a rapid senescence of leaves at or shortly after physiological maturity. Hybrids resistant to root and stalk rot were characterized by a continued increase in vegetative dry matter for several weeks after pollination, resulting in relatively heavy lower stalks and a high ratio of vegetative tissue to grain. The density of pith tissue from the lower stalk at physiological maturity was negatively correlated with subsequent stalk rot incidence.

scholarly journals Maturation and germination of Vernonanthura discolor seeds

2016 ◽  
Vol 40 (2) ◽  
pp. 164-172
Author(s):  
Camila Ribeiro de Souza Grzybowski ◽  
Rosemeire Carvalho da Silva ◽  
Elisa Serra Negra Vieira ◽  
Maristela Panobianco
Keyword(s):  
Native Species ◽  
Dry Matter ◽  
Reproductive Development ◽  
Dry Weight ◽  
Harvest Time ◽  
Germination Test ◽  
Physiological Maturity ◽  
Light Regimes ◽  
Blotting Paper ◽  
Periodic Monitoring

ABSTRACT Vernonanthura discolor is a native species with potential for reclamation of degraded lands, and the manufacture of wood panels. This study has aimed to evaluate the process of maturation and germination of Vernonanthura discolor seeds, determining the harvest time, and conducting the germination test. A periodic monitoring of the reproductive development of sources of Vernonanthura discolor was conducted, located in the municipality of Bocaiúva do Sul, PR, Brazil; and starting from the anthesis, weekly collections of seeds were performed to evaluate the percentage of dry matter, germinating power, and vigor, in order to identify the physiological maturity of the seeds. In the germination test, two combinations of four temperatures (20, 30, 20-30 and 30 °C), and two light regimes were tested, seeking to define the best methodology and evaluation dates of the test. It was concluded that the seeds physiological maturity Vernonanthura discolor reached 45 days after the anthesis, when the maximum values of dry weight, germination and vigor are achieved. Germination test may be conducted on blotting paper at 20 or 25 °C with a supply of light, or at 25 °C in the dark, the first count being on the 13th and the last one on the 29th day after seeding.

scholarly journals Shading Affects Morphology, Dry-matter Partitioning, and Photosynthetic Response of Greenhouse-grown `Chardonnay' Grapevines

HortScience ◽  
2004 ◽  
Vol 39 (1) ◽  
pp. 65-70 ◽  
Author(s):  
Justine E. Vanden Heuvel ◽  
John T.A. Proctor ◽  
K. Helen Fisher ◽  
J. Alan Sullivan
Keyword(s):  
Dry Matter ◽  
Dark Respiration ◽  
Light Response ◽  
Leaf Size ◽  
Dry Weight ◽  
Volume Density ◽  
Response Curves ◽  
Dry Matter Partitioning ◽  
Light Response Curves ◽  
Whole Plant

In order to gain an understanding of the capacity of severely shaded leaves to be productive in dense canopies, the effects of increased shading on morphology, dry-matter partitioning, and whole-plant net carbon exchange rate (NCER) were investigated on greenhouse-grown Vitis vinifera L. `Chardonnay' grapevines. Vines were subjected to whole-plant shading levels of 0%, 54%, 90%, and 99% of direct sun 3 weeks after potting. Data were collected 8 to 10 weeks after potting. Nonlinear regression was used to investigate the relationship of leaf morphological traits and organ dry weights to increased shading. Leaf size was maintained with increased shading to approximately the 90% shading level, while leaf fresh weight, volume, density, and thickness were immediately reduced with increased shading. Root dry weight was most affected by increased shading, and root to shoot ratio was reduced. When nonlinear regressions were produced for light response curves, light compensation point was reduced by approximately 49% by moderate shading, and 61% by severe shading. Shaded leaves approached the asymptote of the light response curve more quickly, and had reduced dark respiration rates, indicating that the morphological compensation responses by the vine allow shaded leaves to use available light more efficiently. However, the long-term ramifications of reduced root growth in the current year on vines with shaded leaves may be significant.

POTENTIAL USE OF STALK pH AND STALK PERCENT DRY MATTER AS ESTIMATORS OF LODGING SUSCEPTIBILITY IN CORN

1984 ◽  
Vol 64 (3) ◽  
pp. 559-564
Author(s):  
J. F. MULDOON ◽  
T. B. DAYNARD ◽  
W. C. LEASK ◽  
M. S. ZUBER
Keyword(s):  
Dry Matter ◽  
Zea Mays L ◽  
Correlation Coefficients ◽  
Dry Weight ◽  
Crushing Strength ◽  
Physiological Maturity ◽  
Grain Moisture ◽  
Per Se ◽  
Potential Use

Fourteen corn (Zea mays L.) hybrids were grown at three locations in 1973 and one location in 1975 to study relationships between stalk pH, percent stalk dry matter (SDM), and percent broken stalks (PBS). The three traits were measured at weekly intervals for 4 or 5 wk encompassing grain physiological maturity in the tests of 1973, and on one date, near maturity, in 1975. Measurements of stalk crushing strength, rind thickness, and dry weight of 5-cm stalk sections were also obtained in 1975. In addition, records of PBS were available for the 14 hybrids from 12 tests grown over 4 yr prior to 1973. All measurements of PBS were transformed as log10 (x + 1) prior to statistical analysis; measurements of PBS, pH and SDM were adjusted by covariance to a common percent grain moisture. Measurements of stalk pH were not consistently related across the 14 hybrids to long-term measurements of PBS. Linear correlation coefficients between SDM and PBS were more consistent (i.e., usually positive) but were generally not statistically significant. Measurements of crushing strength, rind thickness and dry weight of 5-cm stalk sections for the 14 hybrids were not correlated with the 12-test means of PBS. In fact, none of the analytical measurements were as useful as measurements of PBS per se, recorded for individual tests in 1973 and 1975, in predicting hybrid differences in PBS as measured in the 12 tests prior to 1973.Key words: Corn, lodging, stalk pH, stalk dry matter

scholarly journals Plant Growth Response of Two Runner Peanut Cultivars to Reduced Seeding Rate1

2002 ◽  
Vol 29 (1) ◽  
pp. 8-12 ◽  
Author(s):  
H. Tewolde ◽  
M. C. Black ◽  
C. J. Fernandez ◽  
A. M. Schubert
Keyword(s):  
Plant Growth ◽  
Leaf Area ◽  
Dry Matter ◽  
Dry Weight ◽  
Main Stem ◽  
Seeding Rate ◽  
Area Index ◽  
Growth Adjustment ◽  
Total Plant ◽  
Peanut Cultivars

Abstract The ability of peanut plants to adjust to wide plant-to-plant spacing and the use of more precise mechanical planters have not been thoroughly exploited to reduce seeding rates. The magnitude of plant growth adjustment of two runner peanut cultivars to reduced seeding rate was studied in 1992 and 1993. A precision vacuum planter was used to plant the cultivars GK-7 and Southern Runner (SR) in single rows per bed at 8, 12, and 22 seed/m2. Total plant dry matter weight (TDM), leaf area (LA), and main stem height, nodes, and branches were measured six times during each season. Vegetative growth adjustment to reduced seeding rate was detected as early as 52 d after planting (DAP) in 1992 and 42 DAP in 1993. Plants fully adjusted to reduced seeding rate when they began forming pods at 70 DAP in 1992 and 75 DAP in 1993. By this stage, individual plants in the 8 seed/m2 treatment accumulated 2 to 2.7 times as much total dry matter (TDM) as plants in the 22 seed/m2, and all seeding treatments within each cultivar accumulated equivalent amounts of TDM on a unit ground area basis. The 8 seed/m2 treatment produced significantly greater TDM/m2 and leaf area index (LAI) than the 22 seed/m2 treatment by the end of both seasons (132 DAP in 1992 and 152 DAP in 1993). The partitioning of dry weight to pods and leaves was also greatest for the 8 seed/m2 seeding treatment. By the end of the season, the 8 seed/ m2 seeding treatment produced as much as 30% more pod dry weight (PDW) per m2 than the 22 seed/m2 treatment. Plants in the 8 seed/m2 seeding were significantly shorter but produced more main stem nodes and branches than the 22 seed/m2 seeding. Under the conditions of this study, plants of these runner cultivars showed the capacity to grow larger and compensate fully for reduced seeding rate before any measurable pod production began. Pod production, therefore, was not reduced and in some situations increased by reducing the seeding rate to as low as 8 seed/m2.

Persistence of modern varieties and hybrids of carrots and its dependence on the biochemical composition

2020 ◽  
pp. 16-19
Author(s):  
Е.В. Янченко
Keyword(s):  
Botrytis Cinerea ◽  
Sclerotinia Sclerotiorum ◽  
Dry Matter ◽  
Inverse Correlation ◽  
Dry Weight ◽  
Matter Content ◽  
White Rot ◽  
Dry Matter Content ◽  
Important Indicator ◽  
Modern Varieties

Цель исследований – дать оценку сохраняемости и болезнеустойчивости современных сортов и гибридов моркови столовой и определить корреляционные зависимости влияния биохимических показателей качества на сохраняемость и степень поражения моркови столовой различными видами болезней в процессе хранения. Исследования проводились в 2011–2016 годах во ВНИИО – филиале ФГБНУ ФНЦО по общепринятым методикам. В биохимической лаборатории отдела земледелия и агрохимии содержание сухого вещества определяли высушиванием до абсолютно сухого веса, общего сахара – по Бертрану, аскорбиновой кислоты – по Мурри, нитраты – ионоселективным методом. При характеристике моркови столовой важнейший показатель, определяющий его качество – количество сухого вещества и сахаров. В процессе хранения были выявлены следующие болезни моркови: серая гниль (Botrytis cinerea Pers. ex Fr.), белая гниль (Sclerotinia sclerotiorum (Lib.)), белая парша (Rhizoctonia carotae Rad.), альтернариоз (Alternaria radicina M., Dr. et E.). В большей степени сортообразцы моркови столовой поражались серой гнилью. Лучшими по сохраняемости сортообразцами были Корсар (94,6%), F1Берлин (94,5%), Берликум Роял (94,1%) и F1 Звезда (94%). Сохраняемость у зарубежных сортов и гибридов моркови столовой была немного выше, чем у отечественных (на 0,4%) как за счет меньшей величины убыли массы (6,3% против 6,4%), так и потерь от болезней (1,6% против 1,9%). Сохраняемость корнеплодов моркови находится в прямой корреляционной зависимости от содержания сухого вещества (r=+0,41), каротиноидов (r=+0,39), моносахаров (r­=+0,30) и суммы сахаров (r=+0,27). Проявление серой гнили находится в обратной корреляционной связи с содержанием сухого вещества и каротиноидов (r=-0,37 и r=-0,35 соответственно), белой парши – в прямой корреляции с содержанием сухого вещества , моносахаров и дисахаров (r= +0,21; r= +0,39; r= -0,41 соответственно), белой гнили в обратной корреляционной связи с содержанием сухого вещества, моносахаров и дисахаров. The purpose of the research is to assess the persistence and disease resistance of modern varieties and hybrids of carrots and to determine the correlation between the influence of biochemical quality indicators on the persistence and degree of damage to carrots by various types of diseases during storage. The research was conducted in 2011–2016 at ARRIVG – branch of FSBSI FSVC, according to generally accepted methods. In the biochemical laboratory of the Department of Agriculture and Agrochemistry, the dry matter content was determined by drying to absolutely dry weight, total sugar – by Bertran, ascorbic acid – by Murri, nitrates – by the ion-selective method. When describing carrots, the most important indicator that determines its quality is the amount of dry matter and sugars. During storage, the following diseases of carrots were detected: gray rot (Botrytis cinerea Pers. ex Fr.), white rot (Sclerotinia sclerotiorum (Lib.), white scab (Rhizoctonia carotae Rad.), alternariasis (Alternaria radicina M., Dr. et E.). To a greater extent, varieties of table carrots were affected by gray rot. The best preserved varieties were Corsar (94.6%), F1 Berlin (94.5%), Berlicum Royal (94.1%) and F1 Zvezda (94%). The persistence of foreign varieties and hybrids of table carrots was slightly higher than that of domestic ones by 0.4%. both due to a smaller amount of weight loss (6.3% vs. 6.4%) and losses from diseases (1.6% vs. 1.9%). The persistence of carrot root crops is directly correlated with the content of dry matter (r=+0.41), carotenoids (r=+0.39), monosaccharides (r=+0.30) and the amount of sugars (r=+0.27). The manifestation of gray rot is in inverse correlation with the content of dry matter and carotenoids (r=-0.37 and r=-0.35, respectively), white scab is in direct correlation with the content of dry matter (r= +0.21; r= +0.39; r= –0.41, respectively), white rot is in inverse correlation with the content of dry matter, monosaccharides and disaccharides.

Growth, Opium Gum Yield, and Photoperiod Response in Five Opium Poppy (Papaver somniferum L.) Cultivars

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 481d-481
Author(s):  
Z. Wang ◽  
M.C. Acock ◽  
B. Acock
Keyword(s):  
Flowering Time ◽  
Dry Matter ◽  
Dry Weight ◽  
Papaver Somniferum ◽  
Opium Poppy ◽  
Photoperiod Response ◽  
Asian Countries ◽  
Critical Photoperiod ◽  
Growth Chambers ◽  
Positive Correlations

To develop models for estimating growth, flowering time and gum yield of opium poppy, we compared variability among five cultivars (T, L, B1, B2, B3) from different latitudes in three Southeast Asian countries. Variability in the relationships between gum yield, capsule volume, and dry weight was also examined. Plants were grown in six growth chambers at a 11-, 12-, 13-, 14-, 15-, or 16-h photoperiod (PP) with a 12-h 25/20 °C thermoperiod. The main capsule was lanced for opium gum at 10, 13, and 16 d after flowering (DAF). Plants were harvested at 21 DAF and separated into leaves, stems, and capsules. Flowering time for B2 was affected least by PP and B1 the most. Flowering times for B3, L, and T were similar across the range of PPs. All cultivars showed a significant increase in flowering time from 14 to 13 h PP. Cultivars that flowered late (such as B1) had greater biomass than those that flowered earlier. However, cultivars that flowered earlier (such as L) had more dry matter partitioned into capsule than late-flowering ones. B2, B3, and L had the highest gum yields while B1 had the lowest. Positive correlations were found between gum dry weight and capsule volume (or dry weight) for T and L, but no correlations were observed between these variables for B1, B2, and B3. Our results indicated that plant dry weight varied as much as 77% and flowering time varied up to 40% even though the critical photoperiod was the same for all cultivars. The ratio of gum yield to capsule dry weight were significantly different between B1 and T.

scholarly journals EFFECT OF MINERAL DEFICIENCY ON MORPHOLOGICAL AND PHYSIOLOGICAL PARAMETERS AND ON SHOOT AND ROOT MINERAL PARTITIONING IN THREE SUNFLOWER VARIETIES / EFECTO DE LA FALTA DE ELEMENTOS MINERALAS SOBRE LOS PARAMENTROS MORFOLOGICOS Y FISIOLOGICOS Y REPARTICION DE ELEMENTOS MINERALES DE LA PARTE SOBRE EL SUELO Y DE LA RAIZ EN TRES VARIEDADES / INFLUENCE DE LA CARENCE D’ÉLÉMENTS MINÉRAUX SUR LES PARAMÈTRES MORPHOLOGIQUES ET PHYSIOLOGIQUES ET SUR LA DISTRIBUTION DES ÉLÉMENTS MINÉRAUX ENTRE LA PARTIE AÉRIENNE ET LA RACINE POUR TROIS SORTES DE TOURNESOL

Helia ◽  
2001 ◽  
Vol 24 (35) ◽  
pp. 135-148
Author(s):  
Mohammed El Midaoui ◽  
Ahmed Talouizte ◽  
Benbella Mohamed ◽  
Serieys Hervé ◽  
Ait Houssa Abdelhadi ◽  
...  
Keyword(s):  
Leaf Area ◽  
Dry Matter ◽  
Growth Parameters ◽  
Dry Weight ◽  
Mineral Deficiency ◽  
P Deficiency ◽  
Plant Parts ◽  
Shoot Dry Weight ◽  
K Deficiency ◽  
Matter Effect

SUMMARYAn experiment has been carried out in order to study the behaviour under mineral deficiency of three sunflower genotypes, a population variety (Oro 9) and two hybrids (Mirasol and Albena). Sunflower seedlings were submitted to five treatments: N deficiency (N0), P deficiency (P0), K deficiency (K0), N and K deficiency (N0K0) and a control. Plants were harvested when they reached 3-4 true pairs of leaves. Growth parameters measured (height, total leaf area, root length, root and shoot dry mater) were all significantly reduced by mineral deficiency. Leaf area was most reduced by N0 (-61%) and P0 (-56%). Total dry matter was most affected by N0 (-63%) and by N0K0 (-66%). Genotype comparisons showed that Oro 9 had the highest shoot dry matter while Albena had the lowest root dry matter. Effect of mineral deficiency on content and partitioning of N, P, K, Ca and Na was significant and varied according to treatments and among plant parts. Shoot dry weight was significantly correlated with root N content (r2=0.81) and root K content (r2=-0.61) for N0 and K0.

scholarly journals Contribution of green organs to grain weight in dryland wheat from the 1940s to the 2010s in Shaanxi Province, China

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yingying Sun ◽  
Suiqi Zhang ◽  
Jiakun Yan
Keyword(s):  
Dry Matter ◽  
Dry Weight ◽  
Grain Weight ◽  
Shaanxi Province ◽  
Grain Number ◽  
Replacement Process ◽  
Defoliation Treatment ◽  
Winter Wheat Cultivars ◽  
Water Treatments ◽  
Over Time

AbstractEight dryland winter wheat cultivars (Triticum aestivum L.), which were widely cultivated from the 1940s to the 2010s in Shaanxi Province, China, were selected and grown in plots, and two water treatments (irrigation and drought) were used to identify the contribution of ears, leaves and stems to grain weight and grain number associated with cultivar replacement. The plant height and stem dry weight of the dryland wheat decreased significantly during the cultivar replacement process, but there was a remarkable increase in the dry matter translocation of stems under irrigation. Shaded-ear and defoliation treatment could decrease the grain number and grain weight, and the grain weight was more influenced. Both the leaf and ear are important photosynthetic sources for dryland wheat, and the contribution of ear assimilates showed a significant increase over time; however, the contribution of leaf assimilates showed a negative correlation with cultivation over time. The accumulation of stem assimilates and ear photosynthesis both increased the grain weight potential. In the future breeding process, cultivars with more assimilates stored in the stem and greater assimilative capacity of ears, especially a greater contribution of ear assimilates, are expected to increase the grain yield.

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