The convergence of nanotechnology and genome editing in plant sciences is redefining modern precision breeding through efficient, transgene free, tissue culture independent pathways for genetic improvement in crops. Conventional breeding and transgenic tools are limited to genotype dependency, inefficient gene delivery, unpredictable transgene insertions, thereby restricting their application in elite germplasm. Nanoparticles-mediated gene delivery systems have revolutionized the genetic transformation in plants through targeted and transgene free delivery of CRISPR/Cas ribonucleoproteins (RNPs), DNA, and RNA into plant cells, while minimizing genome interference. Nanocarriers are the engineered delivery systems wherein the material component is a nanoparticle. DNA-free delivery refers to the absence of exogenous DNA during editing, whereas transgene free plants are those that do not retain integrated foreign DNA after regeneration. Firstly, this review summarizes current progress in designing nanocarriers, including lipid, polymeric, mesoporous silica nanoparticles, carbon-based nanoparticles, layered double hydroxides, and DNA-based nanoparticles; harnessing the function of their physicochemical traits in modulating plant cellular uptake, cargo stability, controlled delivery, and tissue specific targeting in plants. Secondly, the broad-spectrum roles of nano particles in genome editing, crop protection via RNA interference, organelle-targeted modifications are discussed, stressing transgene free approaches to mitigate somaclonal variation and regulatory concerns to foster public acceptance. The integration of nano-mediated delivery with speed breeding, meristem transformation, multiplexed editing in elite germplasm is proposed as an approach for prompt trait stacking and validation. Thirdly, the collaborative roles of experts in the field of nanotechnology, plant breeding, plant physiology, and agronomy are mentioned for mitigating multifaceted climatic effects and glitches. Moreover, current challenges including nanotoxicity, scalability and field translation, regulatory concerns, and public perception are also discussed. While nanocarrier mediated delivery shows strong potential for improving plant genome engineering, current evidence is largely confined to controlled experimental systems, and significant challenges remain before routine integration into breeding pipelines becomes feasible.

The present investigation was conducted to understand the genetic action for controlling the inheritance of some quantitative characters. The experimental materials consisted of three rice varieties, i.e., Mahsuri, Bhutmuri, IR36 and F1, F2, and F3 populations of Mahsuri×Bhutmuri (Cross I) and IR36×Bhutmuri (Cross II). To conduct the generation mean analysis, the parents and their F1, F2, and F3 populations were evaluated during June to October month of Kharif 2016 and Kharif 2017. Generation mean analysis was done for eighteen quantitative characters following the five parameter model. The Analysis of Variance revealed significant differences among the five generations for all the characters studied. The results of the scaling tests and joint scaling test revealed that the Simple additive-dominance model was inadequate for days to 50% flowering, days to maturity, number of panicles plant-1, number of primary branches panicle-1, number of secondary branches panicle-1 in Cross I, while it was for plant height, number of tillers plant-1, number of panicles plant-1, number of grains panicle-1, number of filled grains panicle–1 and fertility % in Cross II. Hence, the present studies have revealed that epistasis as a basic mechanism that cannot be ignored. Thus, formulating breeding policies on only main gene effects i.e. additive and dominance could be misleading.