Growth, Nodulation and Nitrogen Fixation in Stylosanthes: Effect of Different Day/Night Root Temperatures

1989 ◽  
Vol 25 (4) ◽  
pp. 461-472 ◽  
Author(s):  
R. A. Date

SUMMARYNodulated plants of six varieties of Stylosanthes were grown at a constant temperature of 30°C for 21 days in a controlled environment and then for a further 21 days at a range of day/night root temperatures. Dry matter and nitrogen content of S. hamata cv. Verano and CPI40264A were measured after growth at day/night root temperatures of 30/30, 40/30, 50/30, 60/30 and 60/35°C. Similarly, growth and nitrogen content were measured for Verano, CPI40264A, S. gvianensis cv. Oxley and cv. Cook, S. humilis cv. Lawson and S. scabra cv. Seca after growth at root temperatures of 25/20, 25/25, 30/25, 30/30, 35/30 and 40/30°C. There were strong interactions of root temperature with variety and harvest time (31 and 42 days) but all varieties grew well even at the highest temperatures (50–60°C) provided they were supplied with nitrogen. Symbiotically dependent plants of S. hamata cv. Verano were more tolerant of high root temperatures and maintained better growth and nitrogen fixation at 40/30°C than those of CPI40264A, especially after the 31 day harvest. All six varieties responded similarly, but to differing extents, to the lower range of root temperatures. Nitrogen fixation was more severely affected than dry weight by high root temperature.

1989 ◽  
Vol 25 (4) ◽  
pp. 447-460 ◽  
Author(s):  
R. A. Date ◽  
D. Ratcliff

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.


1986 ◽  
Vol 22 (2) ◽  
pp. 133-147 ◽  
Author(s):  
R. A. Date ◽  
R. J. Roughley

SUMMARYChanges in plant dry weight and nitrogen content of Trifolium semipilosum cv. Safari and T. repens cv. Grasslands Huia were monitored when the root systems of effectively nodulated 28-day-old plants were exposed to a range of constant and diurnal temperatures for 21 days. Nitrogen fixation was more sensitive to high root temperatures than was dry weight accumulation, and T. semipilosum was relatively more tolerant of high root temperatures than T. repens for both dry weight and nitrogen content. The optimum temperatures for dry weight yield and nitrogen fixation (≡nitrogen content) were similar (21–23°C) for both species.Our data suggest that growth and nitrogen fixation in T. semipilosum are more tolerant of short-term exposure to increase in root temperature than in T. repens. In addition, both species accumulated more dry matter and fixed more nitrogen when night temperatures were reduced from either 30 or 35°C to 25°C. The increase was greater with T. semipilosum and may be a major factor in its adaptation to the humid subtropics and cooler (elevated) tropics.


1988 ◽  
Vol 68 (4) ◽  
pp. 935-940 ◽  
Author(s):  
M. TOLLENAAR ◽  
T. W. BRUULSEMA

The response of rate and duration of kernel dry matter accumulation to temperatures in the range 10–25 °C was studied for two maize (Zea mays L.) hybrids grown under controlled-environment conditions. Kernel growth rates during the period of linear kernel growth increased linearly with temperature (b = 0.3 mg kernel−1 d−1 °C−1). Kernel dry weight at physiological maturity varied little among temperature treatments because the increase in kernel growth rate with increase in temperature was associated with a decline in the duration of kernel growth proportional to the increase in kernel growth rate.Key words: Zea mays L, period of linear kernel dry matter accumulation, controlled-environment conditions, kernel growth rate


1969 ◽  
Vol 20 (3) ◽  
pp. 417 ◽  
Author(s):  
JH Silsbury

Lolium rigidum Gaud. and a summer-dormant and a non-dormant form of Lolium perenne L. were grown as seedling plants for 32 days in controlled environment cabinets at constant temperatures of either 10, 20, or 30°C and in all cases with a 16-hr photoperiod at a light intensity of 3600 lm ft-2. Sampling at 4-day intervals permitted the detailed examination of dry matter growth curves. Differences in total dry matter production were related to initial differences in seedling dry weight, and the general responses to temperature were similar for each ryegrass. Total dry matter production was greatest at 20°C and lowest at 10°. A temperature of 30° did not induce dormancy in the summer-dormant ryegrass but did depress growth. Relative growth rate fell with time at each temperature.


2011 ◽  
Vol 48 (No. 8) ◽  
pp. 356-360
Author(s):  
V. Milić ◽  
N. Mrkovački ◽  
M. Popović ◽  
Đ. Malenčić

The objective of the study was to investigate how the inoculation of soybean seed (variety Afrodita, and lines NS-L-2016 and NS-L-300168) with strains of Bradyrhizobium japonicum (1, 1a, 2b), Azotobacter chroococcum (3, 13, 14), and GA3 (gibberellic acid) affected plant dry weight, nitrogen content of nodules and whole plant, the enzymes of nitrogen assimilation (NR, GS) and soluble protein content. The highest dry matter mass and nitrogen content were found in the variety Afrodita, followed by line NS-L-300168. The GS and NR activity was increased significantly by all three inoculation treatments relative to the control. In all three genotypes, the highest values for the enzymatic activity were achieved with treatment mixture of B. japonicum and A. chroococcum strains. Each measurement was performed with three replications. The results were processed using variance analysis and the values were tested with the LSD at 5%.


1976 ◽  
Vol 16 (80) ◽  
pp. 387 ◽  
Author(s):  
P Farrington

Reproductive development, and the distribution of dry matter and nitrogen were followed in field plantings of Lupinus angustifolius cv. Uniharvest and L. cosentinii selection CB12 from the start of flowering until maturity. L. cosentinii (CBI 2) commenced flowering one week earlier, but developed one less order of inflorescences and fewer flowers than L. angustfiolius (Uniharvest) ; yet it set more pods and produced more seed. In both species seeds did not commence to fill until the leaves began to fall shortly after flowering ended. Seeds in pods on all orders of inflorescence filled concurrently. The increase in seed weight coincided with a rapid fall in the nitrogen content of other fractions of the tops.


1977 ◽  
Vol 57 (2) ◽  
pp. 433-439 ◽  
Author(s):  
L. M. BORDELEAU ◽  
H. ANTOUN ◽  
R. A. LACHANCE

Symbiotic nitrogen fixation with 49 isolates of Rhizobium meliloti was studied under controlled environment with alfalfa cv. Saranac. It was shown that plant yield in dry weight can be used as an indirect measurement of nitrogen fixation, and as a criterion for selecting efficient strains of R. meliloti. Statistical study on yields of three cuttings has established that the second cutting gives the most necessary information to correctly evaluate the symbiotic efficiency of the isolates. Six very efficient strains were selected.


1978 ◽  
Vol 58 (1) ◽  
pp. 199-206 ◽  
Author(s):  
M. TOLLENAAR ◽  
T. B. DAYNARD

Kernel development was studied in the maize (Zea mays L.) hybrids United-H106 and Funk’s G-4444, grown in a controlled-environment growth room. A method was employed in which husks were excised, and kernels were removed from the same set of ears at several subsequent sampling dates. This method did not affect the dry matter accumulation of the remaining kernels. Basal kernels (kernel numbers 6–15 in the row) and tip kernels (kernel numbers 31–40) were removed at 2-day intervals during the period from 10 to 20 days postsilking. Dry weight, ethanol-soluble sugar content, and starch content were determined for each sample. Accumulation of dry matter in the tip kernels ceased in a fraction of the United-H106 ears at the onset of the period of linear tip-kernel dry matter accumulation. Only small differences were observed in sugar content between growing and non-growing tip kernels of ears of United-H106. Starch appeared to continue to accumulate in kernels in which dry matter had ceased to accumulate. Except for a delay of approximately 2 days, the pattern of development of tip kernels in Funk’s G-4444 was similar to that of kernels at the base.


2016 ◽  
Vol 40 (2) ◽  
pp. 164-172
Author(s):  
Camila Ribeiro de Souza Grzybowski ◽  
Rosemeire Carvalho da Silva ◽  
Elisa Serra Negra Vieira ◽  
Maristela Panobianco

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.


1969 ◽  
Vol 22 (4) ◽  
pp. 829 ◽  
Author(s):  
AH Gibson

The effect of bacterial strain and root temperature on the retention of nitrogen in the root system of Trifolium Bubterraneum plants was re-examined. The root systems of plants nodulated by the moderately effective Rhizobium trifolii strain NA30 possessed a higher percentage nitrogen than those nodulated by the fully effective strain TAl, although the number of nodules formed by each strain was similar. The difference was due to a greater weight of nodule tissue on the NA30-nodulated plants, and also to a higher percentage nitrogen in the NA30 nodules; this latter effect was due to a higher concentration of non-protein nitrogen. The overall effect of these differences was to reduce the amount of nitrogen translocated to the shoots of the NA30 plants, in both absolute terms and as a proportion of the total amount of nitrogen fixed. Another difference between the two strains was the rate of nitrogen fixation per unit (dry weight or leghaemoglobin content) of nodule tissue.


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