Photosynthetic and storage limitations to yield in Sorghum bicolor (L. Moench)

1976 ◽  
Vol 27 (4) ◽  
pp. 489 ◽  
Author(s):  
RC Muchow ◽  
GL Wilson

Under favourable growing conditions, the source-sink relationships in grain yield of sorghum were analysed in terms of capacities for net assimilation, of head storage, and of the transport system to move assimilates between source and sink. In four commercial hybrids (Dekalb E57, Pacific Goldfinger, Texas 610SR, and Texas 626) grown at three population densities (20.2, 40.4 and 80.8 plants m-1), the assimilates supply was varied by increasing or decreasing the radiation available per plant (by thinning or shading), the potential gram storage capacity was decreased by spikelet removal, and the transport system was reduced by incision of the culm, all manipulations being performed at anthesis. Decreasing the number of grains increased the size of those remaining in all cultivars at all population densities The degree of Increase was greatest for T626 and T610 and least for E57 Thinning increased the grain size In all cultivars, but only sufficiently to cause a significant increase In gram yield In T610 and T626 Reduction in the assimilate supply by shading decreased the gram size and yield in all cultivars. Reduction In the transport system had no significant effect on gram yield. These results showed that there was surplus capacity for storage and transport In all cultivars In T626, T6L0, and Goldfinger, all post-anthesis assimilate was stored as gram and grams could grow larger The yield was therefore completely source-limited In E57, however, not all port-anthesis assimilate was stored as gram, and these grams showed little capacity to grow larger, which suggests that the yield was partially limited by both source and sink.


1975 ◽  
Vol 26 (1) ◽  
pp. 11 ◽  
Author(s):  
KS Fischer ◽  
GL Wilson

In field and glasshouse experiments with grain sorghum (cv. RS610), the assimilate supply was varied by increasing or decreasing radiation and carbon dioxide supply; the potential grain storage capacity was altered by spikelet removal; and the transport system was reduced by incision of the culm. Plants grown at four population densities in the field were manipulated to increase (by removing neighbouring plants) or decrease (by shading) the supply of photosynthates during grain filling. These treatments affected grain size and thus yield. Removal of some of the spikelets at three-quarter anthesis resulted in a significant increase in the size of those grains remaining at maturity. From anthesis onward, a reduction in the capacity of the transport system in the culm had no significant effect on grain yield. These results are interpreted as evidence that grain yield is not limited by the storage capacity of the grain, or by the transport system involved in moving material from the stem to the grain. Treatments which altered the demand for assimilates by the grain, relative to the supply, did not affect net photosynthesis. Dry matter produced in excess of grain requirements accumulated in other plant parts, including the root. Potential grain size was influenced by interspikelet competition operating within 1 week after three-quarter anthesis. *Part II, Aust. J. Agric. Res., 22: 39-47 (1971).



1996 ◽  
Vol 121 (3) ◽  
pp. 473-477 ◽  
Author(s):  
Gina E. Fernandez ◽  
Marvin P. Pritts

A 2-year study was conducted to investigate the influence of the light environment on source-sink relationships in `Titan' red raspberry. Treatments imposed included flower and cane removal in conjunction with partial or whole canopy shading. Raspberry plants were remarkably resistant to a reduction in carbon supply. Yields and primocane production were maintained even when canopies were shaded. Furthermore, if raspberry plants were prevented from producing a full crop in one year, yields the following year tended to be higher than normal. These data, and other studies demonstrating that raspberry roots are strong carbon sinks, suggest that raspberry plants may rely on stored carbohydrate to mature the current crop of fruits when current photosynthate is inadequate. This trait is characteristic of some perennial species adapted to progressively changing environments, but may not be optimal for horticultural situations where growing conditions are relatively constant from year to year. A large root storage capacity and excessive primocane production likely contribute to the relatively low yields that are typical of this species.



2018 ◽  
Author(s):  
Djoko Santoso ◽  
Avinska Tirza ◽  
Eko Januari Wahyudi ◽  
Susanti Alawiyah ◽  
Wawan Gunawan Abdul Kadir ◽  
...  




Sensors ◽  
2019 ◽  
Vol 19 (6) ◽  
pp. 1339 ◽  
Author(s):  
Hasan Islam ◽  
Dmitrij Lagutin ◽  
Antti Ylä-Jääski ◽  
Nikos Fotiou ◽  
Andrei Gurtov

The Constrained Application Protocol (CoAP) is a specialized web transfer protocol which is intended to be used for constrained networks and devices. CoAP and its extensions (e.g., CoAP observe and group communication) provide the potential for developing novel applications in the Internet-of-Things (IoT). However, a full-fledged CoAP-based application may require significant computing capability, power, and storage capacity in IoT devices. To address these challenges, we present the design, implementation, and experimentation with the CoAP handler which provides transparent CoAP services through the ICN core network. In addition, we demonstrate how the CoAP traffic over an ICN network can unleash the full potential of the CoAP, shifting both overhead and complexity from the (constrained) endpoints to the ICN network. The experiments prove that the CoAP Handler helps to decrease the required computation complexity, communication overhead, and state management of the CoAP server.



1975 ◽  
Vol 65 (2) ◽  
pp. 359-372 ◽  
Author(s):  
H J Reimers ◽  
D J Allen ◽  
I A Feuerstein ◽  
J F Mustard

Repeated thrombin treatment of washed platelets prepared from rabbits can decrease the serotonin content of the platelets by about 80%. When these platelets are deaggregated they reaccumulate serotonin but their storage capacity for serotonin is reduced by about 60%. If thrombin-pretreated platelets are allowed to equilibrate with a high concentration of serotonin (123 mu M), they release a smaller percentage of their total serotonin upon further thrombin treatment, in comparison with the percentage of serotonin released from control platelets equilibrated with the same concentration of serotonin calculations indicate that in thrombin-treated platelets reequilibrated with serotonin, two-thirds of the serotonin is in the granule compartment and one-third is in the extragranular compartment, presumably the cytoplasm. Analysis of the exchange of serotonin between the suspending fluid and the platelets showed that thrombin treatment does not alter the transport rate of serotonin across the platelet membrane and does not cause increased diffusion of serotonin from the platelets into the suspending fluid. The primary reason for the reduced serotonin accumulation by the thrombin-treated platelets appears to be loss of amine storage granules or of the storage capacity within the granules.



2021 ◽  
Vol 11 (2) ◽  
Author(s):  
Brendan P. Marsh ◽  
Yudan Guo ◽  
Ronen M. Kroeze ◽  
Sarang Gopalakrishnan ◽  
Surya Ganguli ◽  
...  


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