  We report on the results of investigation the conductivity and
magnetoresistance (MR) temperature dependencies for the two strained multilayer
p-type Ge/Ge_{1-x}Si_x heterostructures. The usual logarithmic temperature
dependencies for zero magnetic field conductivity due to the weak localization
(WL) and electron- electron interaction (EEI) effects take place in both
samples. For one of the samples the negative MR is observed in a whole range of
magnetic fields up to ~1T at T <=12K, but for the other sample the MR
transforms from the negative to positive at B >= 0.2T and T >=1.3K. We
attribute such a behavior to the interplay of two types of holes due to partial
filling of the second subband. Extrapolation of the observed high-field
parabolic MR to B = 0 allows to separate WL and EEI contributions to the total
quantum corrections to conductivity at B = 0 resulting for both of our
structures in that EEI part is ~2/3 and the WL part is ~1/3.
