Ramamoorthy Pushpam

Lignocellulosic energy crops are promising feedstocks for anaerobic digestion, but their biogas potential depends on biomass productivity, composition and digestibility. This systematic review evaluates the effects of agronomic management on biomass production, feedstock quality and biogas/methane yield in lignocellulosic energy crops and identifies key research gaps. A systematic literature search was conducted in the Scopus database for English-language journal articles published from 2005–26, using predefined Boolean terms covering lignocellulosic energy crops, anaerobic digestion/biogas production and agronomic management. Following screening and eligibility assessment, 89 studies were included in the qualitative synthesis. The evidence indicates that nutrient management, irrigation, planting density, harvest timing and frequency and genotype selection strongly influence biomass yield and feedstock characteristics, thereby affecting methane production. Optimised nutrient management can improve biomass productivity and substrate quality, whereas excessive nutrient inputs may reduce nutrient-use efficiency and adversely affect digestion performance. Harvest timing is critical because increasing biomass yield with maturity may be associated with greater lignification and reduced digestibility. Ensiling, pretreatment and co-digestion can further improve feedstock accessibility and methane recovery. However, evidence remains heterogeneous, with limited integration of agronomic performance, methane productivity, environmental impacts and economic feasibility. Future research should prioritise standardised methods, long-term field-to-digester studies and integrated environmental and economic assessments. Overall, coordinated optimisation of agronomic practices and anaerobic digestion is essential for sustainable biomethane production.

Herbicides that inhibit 4-hydroxyphenylpyruvate dioxygenase (HPPD) are widely used for broad-spectrum weed control; however, the sensitivity of many crop species limits their application, underscoring the need for the development of HPPD-tolerant crops. Although numerous herbicides are commercially available, HPPD inhibitors are particularly effective for controlling weeds resistant to glyphosate, glufosinate, dicamba, and other herbicides, as instances of evolved resistance to HPPD inhibitors remain low. Major genetic strategies for developing HPPD tolerance include the transgenic introduction of microbial HPPD enzymes with reduced herbicide sensitivity, mutagenesis-based approaches that have yielded novel HPPD alleles, and precise genome modification using CRISPR–Cas9 technology. In addition, protein engineering and directed evolution have been employed to generate HPPD variants with reduced inhibitor sensitivity. Future progress will depend on integrating advanced molecular tools with sustainable weed-management practices to ensure durable trait performance, minimize ecological and regulatory concerns, and reduce gene-flow risks associated with herbicide-tolerant crops.

Forage sorghum (Sorghum bicolor L. Moench), a climate-resilient, drought-tolerant fodder crop with high adaptability and biomass potential, plays a significant role in addressing global livestock feed and fodder demands. However, its complex quantitative quality traits, such as crude protein, fibre fractions, crude fat, lignin and antinutritional factors like hydrogen cyanide (HCN) content, show considerable variation across genotypes and are strongly influenced by developmental stage, management practices and environmental conditions. This review comprehensively summarises the genetic and molecular strategies for improving forage quality traits in sorghum, highlighting key trait relationships, yield-quality trade-offs, harvesting effects and emerging genomic tools to accelerate the development of nutritionally superior and safer forage sorghum cultivars. Conventional breeding programs have contributed to the development of improved forage sorghum cultivars. Brown midrib lines have emerged as a successful breeding strategy, with average neutral detergent fibre (NDF) and acid detergent fibre (ADF) contents of 57.5 % and 33.67 % dry matter (DM), compared to 59.45 % and 36.51 % DM in conventional varieties. However, this is often accompanied by biomass yield penalties of approximately 14.33 %. Recent advances in molecular breeding, such as functional genomics, genome-wide association studies (GWAS), quantitative trait loci (QTL) mapping, marker-assisted selection and antisense-mediated downregulation, have enabled the precise identification of the genetic architecture of forage quality traits. In particular, QTL mapping uncovered 43 overlapping QTLs controlling various forage quality traits and biomass traits, demonstrating their interconnections and possibilities for their simultaneous improvement. The identified candidate genes and pleiotropic loci controlling forage quality traits offer new opportunities for genomic-assisted improvement, where gene-editing tools such as CRISPR/Cas9 can simultaneously enhance feed safety, biomass yields and nutritional quality.

Drought is one of the most critical abiotic stresses limiting crop productivity by disrupting cellular water balance, inducing oxidative stress, and impairing photosynthetic metabolism. In rice (Oryza sativa L.), drought triggers a cascade of physiological and biochemical adjustments that determine genotypic resilience, including enhanced antioxidant activity, osmotic regulation, and membrane protection. To elucidate these adaptive mechanisms, a core set of 16 rice genotypes was developed from an initial panel of 150 accessions, representing maximum physiological and biochemical diversity. These genotypes were evaluated under drought and irrigated conditions for key traits such as relative water content (RWC), membrane stability index (MSI), nitrate reductase (NR) activity, peroxidase (POD), catalase (CAT), superoxide dismutase (SOD), proline (PRO), SPAD chlorophyll index, and yield. Significant genotypic variation was observed across all traits. Correlation analysis revealed that yield under drought was positively associated with SOD, MSI, and RWC, highlighting the critical role of antioxidant defense and cellular water retention in sustaining photosynthetic function. Principal component analysis (PCA) efficiently captured the multidimensional variation among genotypes, while the Multi-Trait Genotype–Ideotype Distance Index (MGIDI) enabled integrated selection for physiological and biochemical efficiency. Genotype 5(RL-5750), 6(RL-9815) and 4(RL-4499) exhibited superior adaptive responses under drought, whereas genotype 1(RL-671), 3(RL-2503) and 2(RL-1682) performed best under irrigation. This integrative physiological framework demonstrates that drought tolerance in rice is governed by coordinated antioxidant regulation, membrane stability, and tissue hydration. The findings provide a mechanistic basis for identifying physiological markers and elite genotypes, offering valuable resources for breeding programs aimed at improving drought resilience and yield stability in rice.

With growing global demand for sustainable livestock systems and nutritious animal products, the importance of resilient and high‐quality forage crops is becoming increasingly evident. Conventional forages often fail to meet both the nutritional and climatic resilience needs of modern livestock systems. Small millets, traditionally underutilized and often classified as orphan crops, offer a promising alternative. These hardy cereals can thrive in marginal environments, require low inputs, and possess superior nutritional profiles, high calcium and iron, making them valuable for animal health and productivity. Despite their well‐established role in human nutrition, their potential as forage crops remains largely underexplored. This review highlights the suitability of small millets for forage production, especially in regions facing climatic challenges such as those in the Asia–Pacific. We emphasize their relevance to sustainable development goals (SDGs) and discuss how emerging technologies, such as omics‐driven breeding and genetic engineering, can unlock their underutilized genetic potential. Although research on small millets is less advanced than in pearl millet or sorghum, their ability to thrive in harsh conditions makes them suitable for resilient forage systems. Using small millets as forage can improve food security, promote sustainable farming, and ease pressure on conventional feed sources.

Rice production faces severe challenges from abiotic stresses, including drought, salinity, heat, cold and nutrient imbalance, causing yield losses of 30-70 % depending on stress severity and developmental stage. SQUAMOSA promoter binding protein-LIKE (SPL) genes, regulated primarily by miR156 and miR529, have emerged as key transcriptional regulators of abiotic stress tolerance in rice. This review synthesizes current research on SPL gene functions in stress adaptation, examining their roles in hormone signalling, ion homeostasis and developmental regulation during both vegetative and reproductive stages. We analyse functional genomics and reverse genetics studies demonstrating SPL contributions to yield improvement and stress tolerance and evaluate recent advances in CRISPR/Cas9 and base editing technologies for precise SPL gene modulation. The findings reveal distinct tissue specific and developmental stage specific functions of miR156/miR529-SPL regulatory modules, with miR156 predominantly controlling vegetative development while miR529 regulates reproductive processes. This review provides a framework for leveraging SPL gene networks in developing climate-resilient rice varieties through targeted genome editing approaches.

The increasing global demand for nutrient-dense, functional foods has fuelled interest in microgreens, which are young, edible seedlings harvested at the cotyledon or first true leaf stage. These miniature greens are valued for their vibrant appearance, concentrated flavors and superior nutritional content, including high levels of vitamins, minerals, antioxidants and secondary metabolites. This review discusses recent developments in microgreen cultivation, including advances in soilless substrates, controlled environment agriculture, seed density optimization, seed treatments and fertilization strategies. Substrates such as cocopeat, peat moss and jute fiber, along with hydroponic and aeroponic systems, have been shown to enhance yield and nutrient concentration. Manipulating light quality, particularly with red and blue LED combinations, significantly improves plant growth and phytochemical content. Seed treatments, including nutrient biofortification and disinfection, further promoted germination, nutrient uptake and safety. Although microgreens generally contain lower levels of anti-nutritional factors like phytic acid compared to their mature counterparts, these compounds can still impact mineral bioavailability. However, research demonstrates that targeted biofortification can effectively reduce such limitations. This review provides a comprehensive overview of the production techniques, nutritional potential and safety considerations of microgreens, highlighting their relevance as a sustainable and health-promoting food source.