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This is the second in a series of papers based on data from DISCS, aSubmillimeter Array observing program aimed at spatially and spectrallyresolving the chemical composition of 12 protoplanetary disks. We present dataon six Southern sky sources - IM Lup, SAO 206462 (HD 135344b), HD 142527, AS209, AS 205 and V4046 Sgr - which complement the six sources in the Taurus starforming region reported previously. CO 2-1 and HCO+ 3-2 emission are detectedand resolved in all disks and show velocity patterns consistent with Keplerianrotation. Where detected, the emission from DCO+ 3-2, N2H+ 3-2, H2CO 3-2 and4-3,HCN 3-2 and CN 2-1 are also generally spatially resolved. The detectionrates are highest toward the M and K stars, while the F star SAO 206462 hasonly weak CN and HCN emission, and H2CO alone is detected toward HD 142527.These findings together with the statistics from the previous Taurus disks,support the hypothesis that high detection rates of many small molecules dependon the presence of a cold and protected disk midplane, which is less commonaround F and A stars compared to M and K stars. Disk-averaged variations in theproposed radiation tracer CN/HCN are found to be small, despite two orders ofmagnitude range of spectral types and accretion rates. In contrast, theresolved images suggest that the CN/HCN emission ratio varies with disk radiusin at least two of the systems. There are no clear observational differences inthe disk chemistry between the classical/full T Tauri disks and transitionaldisks. Furthermore, the observed line emission does not depend on measuredaccretion luminosities or the number of infrared lines detected, which suggeststhat the chemistry outside of 100 AU is not coupled to the physical processesthat drive the chemistry in the innermost few AU.

Disk Imaging Survey of Chemistry with SMA: II. Southern Sky Protoplanetary Disk Data and Full Sample Statistics