Body of Abstract: Crop biotech improvement requires approaches beyond DNA editing. RNA targeting tools, such as CRISPR-Cas13, offer new avenues for specific gene regulation for trait manipulation. To help develop this technology for use in plants, we explored Cas13-dependent silencing in plants against both viral and endogenous RNA. Expressing Cas13 with single- or multi-guide crRNA targeting turnip mosaic virus (TuMV) prevented viral accumulation in Nicotiana benthamiana. Interestingly, we observed that multi-guide crRNA could reduce TuMV accumulation in the absence of Cas13, which we termed guide-induced gene silencing (GIGS). Sequencing small RNA (sRNA) from tissue expressing multi-guide crRNA against an endogenous transcript revealed that many secondary sRNA were produced in a size range indicating that endogenous RNA silencing pathways contribute to this phenomenon. Intriguingly, we discovered that the multi-guide crRNA could be expressed and elicit RNA reduction without any intervening sequences between the complimentary regions, and therefore refer to these RNA as short multi-repeat transcripts (SMRT). To further determine how to use this new RNA silencing approach, we evaluated numerous design parameters in plants. We found that SMRT-silencing is independent of guide arrangement within the multi-guides. The systemic expression of PDS multi-guides of varying lengths, from 18 to 28 nucleotides, showed a decrease in silencing strength with decreasing target length. Importantly, we found that increasing the guide dosage, such as the number of times the RNA is targeted with single or multiple sequences, causes increased silencing. Expressing SMRTs in soybean hairy roots showed that our design parameters additionally work in this important crop. Results from RNA-sequencing show high-fidelity SMRT-silencing in soybean roots, and importantly, sRNA sequencing suggests that targeting a transcript at fewer locations produces fewer secondary sRNA. Overall, we have developed a simple and flexible novel approach to regulate gene expression in plants that open new avenues for transcriptome engineering in crops.