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[Objective]The aim of this paper was to screen Paspahim dilatalum germplasms with strong drought resistance, and provide theoretical basis for the breeding and promotion of drought resistant germplasm. [Method] A drought simulation pot experiment was carried out with six P. dilatalum germplasms, and then the changes of various physiological indexes under drought stress were evaluated by means of principal component analysis and membership function. [Result] Under drought stress, the malondialdehyde contents of all the six germplasms gradually increased from the start to the 21st day, then a sharp increase was observed during 21st -28th days. The peroxidase activity, catalase activity,and soluble protein content increased first and then decreased,reached the maximum at 14 day,with one exception that the soluble protein in P. dilatalum germplasm coming from Meitan, Guizhou reached the maximum at 7th d. The total soluble sugar content displayed a significant upward trend,while the chlorophyll content showed a significant downward trend. The results of principal component a-nalysis showed that the cumulative contribution rate of the first three principal components reached 92.64 % ,which could be identified as a comprehensive index for drought resistance evaluation. Comprehensive evaluation of drought resistance showed that the drought resistance of the P. diliilatum germplasm from USA was the strongest,followed by the one from Anlong (grass slope) , Guizhou, the one from Vietnam was relatively weak, and the other germplasms rank in the medium position. [ Conclusion ] In the breeding and promotion of drought-resistant P. dilaUitum germplasms, American P. ddalatum germplasms with stalwart drought resistance should be selected priorly. [ABSTRACT FROM AUTHOR]

Aiming at the bandwidth allocation problems in virtual networks, this paper presented an adaptive bandwidth allocation algorithm based on two stage controller system. The controller system consisted of a set of SP controllers including VN subcontrollers and InP controllers. Firstly, the performance for each VN at every control interval could be locally approximated by a linear model in order to find the relationship between its past and current bandwidth allocation and its past performances in terms of packet delays. Then, basing on the physical link capacity constraints, the system was response of the requested bandwidth from each VN and adjusted dynamicly in order to achieve flexible distributed autonomous control of the reasonable bandwidth allocation to each VN. The simulation results show that the proposed algorithm can not only allocate the available link capacity reasonably and dynamiclly among multiple VN, but also can improve the availability for total bandwidth and the fairness for bandwidth allocation to meet the QoS requirement of each VN. [ABSTRACT FROM AUTHOR]