Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated gene (Cas) system and RNA interference (RNAi)-based non-transgenic approaches are powerful technologies capable of revolutionizing plant research and breeding. In recent years, the use of these modern technologies has been explored in various sectors of agriculture, introducing or improving important agronomic traits in plant crops, such as increased yield, nutritional quality, abiotic- and, mostly, biotic-stress resistance. However, the limitations of each technique, public perception, and regulatory aspects are hindering its wide adoption for the development of new crop varieties or products. In an attempt to reverse these mishaps, scientists have been researching alternatives to increase the specificity, uptake, and stability of the CRISPR and RNAi system components in the target organism, as well as to reduce the chance of toxicity in nontarget organisms to minimize environmental risk, health problems, and regulatory issues. In this review, we discuss several aspects related to risk assessment, toxicity, and advances in the use of CRISPR/Cas and topical RNAi-based technologies in crop management and breeding. The present study also highlights the advantages and possible drawbacks of each technology, provides a brief overview of how to circumvent the off-target occurrence, the strategies to increase on-target specificity, the harm/benefits of association with nanotechnology, the public perception of the available techniques, worldwide regulatory frameworks regarding topical RNAi and CRISPR technologies, and, lastly, presents successful case studies of biotechnological solutions derived from both technologies, raising potential challenges to reach the market and being social and environmentally safe.

Carioca grains are the most cultivated commercial group of common bean and Fusarium oxysporum f. sp. phaseoli (Fop) is an important disease under field conditions. Genetic resistance is the most effective control strategy. Thus, our objective was to study the inheritance of Fop resistance in the carioca grain type common bean. Lines CNFC 11965 (S) and CVIII 8511 (R) were crossed to obtain F 1 and F 2 generations and backcrosses, inoculated with the isolate FOP UFV 01, and severity grades used to estimate genetic parameters. Segregation of resistant and susceptible plants in the F 2 generations and backcrosses resulted in dominant monogenic inheritance of Fop resistance. The high values of heritability emphasized the probability of success in the selection processes because environmental factors were not significant. The carioca grain line CVIII 8511 is promising, and its Fop resistance gene can be transferred to commercial cultivars of this group using the backcross method.

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A tecnologia de edição genômica CRISPR/Cas, desenvolvida a partir do sistema imune bacteriano, vem revolucionando diversas áreas, incluindo o controle de doenças de plantas. Considerado uma técnica simples, com alta especificidade e fácil uso, o sistema CRISPR/Cas permite a manipulação genética até mesmo de culturas com genoma com alta poliploidia, longo ciclo de vida e moroso processo de regeneração. Com isso, a técnica fornece uma oportunidade de criar novas cultivares com características benéficas de forma rápida, eficiente e sustentável para o controle de fitopatógenos. Nesta revisão, foram descritos o histórico da descoberta, funcionamento, adaptação e mecanismos de reparo do sistema CRISPR/Cas com foco na edição genômica de plantas. Além disso, abordou-se os avanços recentes relacionados à descoberta de variantes e engenharia das enzimas Cas, estratégias para o aumento da especificidade e efetividade da tecnologia, formas de entrega das biomoléculas em plantas e outras aplicações do sistema CRISPR/Cas, tais como a regulação de genes e detecção dos sítios de ação por meio de proteínas fluorescentes. Foram incluídos também exemplos do uso de CRISPR/Cas na edição genômica de plantas e patógenos visando ao aumento da resistência de plantas a fungos, bactérias, vírus e nematoides.