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Start Over Coverage 421-427

1. Further improvements of the orbital program system POTSDAM-5 and their utilization in geodetic-geodynamic investigation

Creator:
Gendt, G.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
satellite orbit, program system Potsdam-5, and improvements
Language:
Czech
Description:
The program system POTSDAM-5 had been developed in the last years on the basis of POTSDAM-4. It is implemented on the computer EC 1040 and shall provide a model accuracy of some cm. This high precision can only be achieved by improvements of the reference system, force mode and parameter estimation. Results are presented using laser data for the dermination of station coordinates, baselines and polar motion.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

2. Low night temperature-induced changes in photosynthesis and rubber accumulation in guayule (Parthenium argentatum Gray)

Creator:
Sundar, D. and Ramachandra Reddy, A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
chlorophyll, fructose-6-phosphate, net photosynthetic rate, photosystems 1 and 2, proteins, rubber transferase, starch, saccharose, sucrose phosphate synthase, and superoxide dismutase
Language:
Multiple languages
Description:
Three-year-old plants of Parthenium argentatum Gray cv. 11591 grown under natural photoperiod were exposed for 60 d to low night temperature (LNT) of 15 °C (daily from 18:00 to 06:00). Effects of the treatment on net photosynthetic rates (PN), rubber accumulation, and associated biochemical traits were examined. LNT initially reduced PN with a parallel decline in the activities of ribulose-1,5-bisphosphate carboxylase, fructose bisphosphatase, and sucrose phosphate synthase for 20-30 d. Later, LNT enhanced PN and the activities of photosynthetic enzymes. Associated with high PN in LNT-treated guayule plants was a two-fold increase in rubber content and rubber transferase activity per unit of protein. The initial decrease in PN in LNT-treated guayule was associated with low content of chlorophyll (a+b), large starch accumulation, and higher ratio of glucose-6-phosphate/fructose-6-phosphate. Photosystem 2 activity in isolated chloroplasts was initially decreased, but increased after 30 d. There was a significant increase in the leaf soluble protein content in LNT-treated plants. Hence the photosynthetic performance of plants grown at 15 °C night temperature for 50 d was superior to those grown under natural photoperiod in all parameters studied. The high photosynthetic capacity may contribute to superior rubber yields under LNT. and D. Sundar, A. Ramachandra Reddy.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public