Strigolactones (SLs) play significant role in shaping root architecture whereby auxin-SL crosstalk has been observed in SL-mediated responses of primary root elongation, lateral root formation and adventitious root (AR) initiation. Whereas GR24 (a synthetic strigolactone) inhibits LR and AR formation, the effect of SL biosynthesis inhibitor (fluridone) is just the opposite (root proliferation). Naphthylphthalamic acid (NPA) leads to LR proliferation but completely inhibits AR development. The diffusive distribution of PIN1 in the provascular cells in the differentiating zone of the roots in response to GR24, fluridone or NPA treatments further indicates the involvement of localized auxin accumulation in LR development responses. Inhibition of LR formation by GR24 treatment coincides with inhibition of ACC synthase activity. Profuse LR development by fluridone and NPA treatments correlates with enhanced [Ca²⁺]_cyt in the apical region and differentiating zones of LR, indicating a critical role of [Ca²⁺] in LR development in response to the coordinated action of auxins, ethylene and SLs. Significant enhancement of carotenoid cleavage dioxygenase (CCD) activity (enzyme responsible for SL biosynthesis) in tissue homogenates in presence of cPTIO (NO scavenger) indicates the role of endogenous NO as a negative modulator of CCD activity. Differences in the spatial distribution of NO in the primary and lateral roots further highlight the involvement of NO in SL-modulated root morphogenesis in sunflower seedlings. Present work provides new report on the negative modulation of SL biosynthesis through modulation of CCD activity by endogenous nitric oxide during SL-modulated LR development.

Plants are associated with diverse microbial communities that play a crucial role in plant growth promotion and improving stability under stress conditions. Microbiome engineering involves the targeted manipulation, recruitment, and optimization of plant-associated microbial communities to enhance plant performance. However, the effectiveness of microbiome engineering can vary with plant genotype, environmental conditions, microbial composition, and the stability of introduced or selected communities. This review paper summarizes emerging strategies for plant microbiome engineering, including synthetic microbial consortia (SynComs) and host-mediated microbiome selection. SynCom approaches involve the rational assembly of selected microbial strains at the community scale, whereas host-mediated engineering uses plant–microbiome interactions and host genetic variation to enrich beneficial microbial communities. Evidence suggests that combining complementary microbial functions with host-mediated selection may improve microbiome establishment and functional consistency; however, translating these benefits into reliable field performance remains challenging because of context-dependent microbial interactions, competition with resident communities, and limited long-term persistence. Furthermore, this review also discusses omics technologies, including metagenomics, metabolomics, and transcriptomics, which facilitate the identification of functional microbial traits and plant–microbe interactions. Artificial intelligence and machine learning provide complementary tools for microbiome prediction and targeted intervention design. However, their predictive reliability depends on representative datasets, robust validation, and integration of environmental and biological variables. The review highlights that successful microbiome engineering requires a shift from microbial community assembly alone toward functionally validated, ecologically stable, and field-tested strategies. Integrating microbiome engineering with multi-omics, AI-driven prediction, and precision agriculture could support more predictable, resilient, and sustainable crop production.

Plants produce a large variety of non-proteinaceous biochemicals through primary and secondary metabolism. These compounds may act as signaling molecules, plant hormones, growth regulators (other than hormones) or as protectants from parasitic infections. In various attempts by scientists world over, a number of novel plant growth regulators have been discovered in the recent past. Over the past decade interesting information has been obtained on the biosynthesis, photomodulation and physiological roles of strigolactones (SLs) which are derived from carotenoid biosynthesis route. Adequate evidence is now available on their actions through transport to the target sites in the plant system. The regulatory roles of strigolactones have further been observed to be modulated by light in more than one ways. Present investigations report the photomodulation of strigolactones (SLs) in sunflower seedlings growth at their early developmental stages (2d, 4d, 6d). These observations indicate the migration of a probable light-sensitized signaling molecule (yet to be identified) or a SL precursor from light exposed aerial parts to the seedling roots maintained in dark. Thus, a photomodulation and migration of SL precursor/s is evident from the present work.