Assam Agricultural University (AAU) is an agricultural education state university which was established on 1 April 1969 in Jorhat in the state of Assam, India. The jurisdiction of the university extends to the entire State of Assam with regard to teaching, research and extension education in the field of agriculture and allied sciences. The university has a number of campuses with its headquarters at Borbheta, Jorhat.
Rice is one of the main cereal grains consumed on a regular basis in underdeveloped and developing nations across the globe. As a water-intensive crop, rice is particularly susceptible to drought stress, which adversely affects global food security. Global climate change has significantly increased the intensity and frequency of droughts. Drought stress strongly influences several physiological, morphological, biochemical, and agronomic parameters, directly affecting crop output. Plants use a variety of defence mechanisms, such as ROS-scavenging mechanisms, synthesis of various osmolytes, secondary metabolites, and phytohormones, to adapt to stressful environments. The candidate genes and metabolic pathways crucial to drought resistance in rice are getting revealed by recent advancements in molecular biology tools combined with enhanced breeding methodologies. In order to develop rice cultivars with increased drought tolerance, it will be extremely helpful to understand the ‘omics’ responses in rice during drought stress, particularly of tolerant genotypes. Moreover, molecular breeding techniques, enhanced agronomic management, genome editing, and genetic engineering may make substantial contributions in this regard. The integration of multi-omics methods, including genomics, transcriptomics, proteomics, metabolomics, and ionomics, offers a comprehensive understanding of cellular dynamics in plants under water deprivation. Therefore, it is imperative to utilize omics data from many molecular pathways to develop drought-resistant rice varieties for changing climatic circumstances. This article provides a comprehensive review of research on morpho-physiological, biochemical, molecular, and omics approaches, along with their applications in developing drought-tolerant rice varieties to address global food security concerns.
Light is essential in regulating plant growth and development across their life cycle as a crucial factor in photosynthesis and energy production. Plants adjust their morphological traits in response to light intensity and quality changes. However, the impact of light quality on pigment levels, oxidative stress, reactive oxygen species (ROS) generation, antioxidant defense mechanisms, and biomass production continues to be a subject of ongoing investigation. Specialized photoreceptors allow plants to perceive light signals across various wavelengths, activating downstream signaling pathways that modify gene expression and affect physiological and developmental processes. This review explores the recent potential of dynamic lighting strategies in regulating plant growth and development, specifically seedling development. Furthermore, it highlights the importance of the circadian system in aligning internal biological rhythms with external light cycles, which is essential for regulating seasonal growth and dormancy in plants. Further, an effort has been made to understand the molecular mechanisms of light-regulated gene transcription, the role of plant hormones in light signal transduction, and their effects on plant physiology, summarizing prior research and assessing the significant influence of light quality on plants.
This study investigated the expression of key flavonoid biosynthetic genes (CHS, CHI, ANS, and FLS) across developmental stages and organs in three onion (Allium cepa L.) genotypes (PRO-6, Rec-1404, and D-97-B). Gene expression exhibited stage-dependent variation, with maximum activity in bulb organs at stages S3 and S4, particularly in the PRO-6 genotype. Elevated transcript levels corresponded with increased total phenolic, quercetin, and anthocyanin contents, signifying enhanced flavonoid biosynthesis during bulb maturation. Cytotoxicity assays on HeLa and HCT-15 cell lines indicated dose- and time-dependent declines in cell viability, with HeLa cells showing greater susceptibility. PRO-6 onion extracts displayed the highest cytotoxic potential, consistent with their enriched flavonoid profiles. The study highlights genotype-, organ-, and stage-specific regulation of flavonoid metabolism in onions and establishes a link between pigment biosynthesis and cytotoxic activity. These results suggest that colored onion genotypes possess significant nutraceutical and therapeutic potential due to their superior bioactive compound composition.
Leaf morphology is a key taxonomic character in angiosperms, yet qualitative descriptions often fail to resolve closely related species exhibiting subtle shape variation. In this study, elliptic Fourier analysis (EFA) was employed to quantitatively assess leaf outline variation among ten species of Ardisia (Primulaceae) collected from wild populations in Assam, India. Leaf outlines were digitized using vector-based tracing, standardized through centering, scaling, alignment and interpolation, and analysed using elliptic Fourier descriptors. Harmonic power analysis indicated that 19 harmonics were sufficient to explain more than 95
Cutworms, particularly Agrotis ipsilon (Hufnagel), are major pests of cabbage, causing substantial yield losses. Their concealed feeding habit and polyphagous nature complicate management, often requiring synthetic insecticides that raise concerns regarding safety and soil health. Although several insecticides have been evaluated for their efficacy against A. ipsilon, little is known about their concurrent effects on soil microbial populations and enzymatic activities in cabbage agroecosystem. Therefore, this study bridges that gap by assessing both pest control efficacy and soil microbial dynamics, thereby providing insights into sustainable pest management strategies under current agricultural practices. To address this, a study was conducted to assess the effectiveness of four insecticides in reducing the infestation of A. ipsilon in cabbage and to determine its impact on soil biological health. Among all the insecticides, the maximum per cent reduction of A. ipsilon was observed in the plots treated with chlorantraniliprole 0.4 GR (Granule) followed by imidacloprid 70 WDG (Water Dispersible Granule) which was statistically at par with clothianidin 50 WDG. Soil microbial population analysis revealed a decrease in both bacterial and fungal colonies in the treated plots compared to control, with chlorantraniliprole 0.4 GR-treated plots maintaining the highest microbial populations, followed by clothianidin 50 WDG. Both phosphomonoesterase (PME) and fluorescein diacetate (FDA) activity in treated soils significantly decreased relative to the control. Chlorantraniliprole 0.4 GR-treated plots recorded the highest PME and FDA activity, followed by clothianidin 50 WDG and thiamethoxam 25 WG (Wettable Granule). The greatest reductions in microbial populations, PME and FDA activity were observed at 15 Days After Spraying (DAS), but these parameters gradually recovered by 30 and 45 DAS, indicating soil resilience to the insecticides. These findings highlight chlorantraniliprole 0.4 GR as an effective and economically viable solution for managing A. ipsilon in cabbage while minimizing long-term adverse effects on the soil ecosystem.
