## 2 Advances and Achievements in Seed Biotechnologies in the Decade 2014-2024
### Seed Quality Improvement Through Biotechnological Innovations
#### 2.2.5 Synthetic Biology Approaches in Seed Quality Improvement  
The advances in synthetic biology and molecular tools have witnessed new paradigms in multiple scientific fields, including agriculture. It defines great prospects in the modification of the genetic framework, biosynthetic pathways, and architecture of plants for crop improvement [147], while microbial applications pertain to biocontrol agents and biofilitizers for plant productivity [148]. In addition, the development of modern engineering tools, like clustered regularly interspaced short palindromic repeat/CRISPRR-associated protein (CRISPRR-Cas9), has assisted in crop breeding and the creation of desired chimeric crops with high-value traits, creating novel avenues in crop improvement. Synthetic biology has been instrumental to useful applications in agriculture--in crop breeding and domestication, photosynthetic modifications, plant nitrogen fixation, and microbiome engineering, among others [149]. The advanced approaches, namely zinc-finger nucleases (ZFNs), CRISPR from _Prevotella_ and _Francisella_ 1 (CRISPRR/Cpf1), and CRISPR-Cas9, are required to maintain consistent seed quality and viability across generations and to be attempted in model plants. The translational success achieved in crop seeds has expanded the horizons in increased seed shelf life and alterations in seed quality in multiple plant species. Studies on genetic modifications in economically important crops, soybean, _Jatropha_, Bt (_Bacillus thuringiensis_) cotton, Bt chickpea, etc., have targeted genes for shelf life, seed oil content, and pest resistance, among others [150, 151, 152]. The progress achieved in the genetic manipulation of seeds has considerably expanded the horizons and achieved translational success in improving quality traits. Modern biotechnologies, namely genetic engineering, genome editing, and biofortification, have been important for enhancing seed nutritional profiles and comprise an emerging area of research [153]. Crop engineering for iron biofortification has concentrated on improving chelating compounds and metal-binding protein concentration, and enhancing promoters in the edible parts of crops [154]. In _Oryza sativa_ L., iron is present in seeds in the aleurone layers, integuments, and scutellum but is lost during milling treatment. Research has targeted rice endosperm to increase iron concentration [155]. Studies have documented that the overexpression of the _ferritin_ gene (under OsGluB1 promoter) considerably improved iron concentration (2 to 3.7-fold increase) in polished rice grains [156]. In wheat, efforts to increase iron concentration in the endosperm, _Agrobacterium_-mediated transformation has been achieved with 30% transformation efficiency [157]; however, the procedure is less effective and expensive. Moreover, zinc biofortification in rice has been achieved--[PERSON] et al. [158] discussed the overexpression of soybean _ferritin_ (_soyferth-1_) and _nicotianamine synthase_ (_Osntas2_) genes (iron transporters) and a significant increase in iron and zinc concentration in polished grains. The genetically engineered golden rice produces beta-carotene (vitamin A precursor) in the grains and demonstrates the potential to address vitamin A deficiency, a global health concern [159, 160]. [PERSON] et al. [161] reported increased folate concentration in rice (approx. 150-fold) via the overexpression of _aminodeoxycharismate synthase_ (_adcs_) and _Arabidopsis gtp-cyclohydrolase i_ (_gtcchi_) genes. [PERSON] and coworkers [162] produced transgenic rice seeds having fragrance via the TALEN-mediated knockout of the _Osbadh2_ gene. In a similar study, the _lipoxygenase_ (_lox3_) gene in rice seeds was targeted for improved storage [163]. The TALEN technology has been successful in improving seed quality and applied to _T. aestivum_, _O. sativa_, _Nicotiana tabacum_ L., _A. thaliana_, _Lyopersicon esculentum_ L., etc. [164, 165, 166, 167, 168].