Effect of silicon application with mycorrhizal inoculation on Brassica juncea cultivated under water stress

Comparative transcriptomic analysis of the nodulation-competent zone and inference of transcription regulatory network in silicon applied Glycine max [L.]-Merr. Roots

KEY MESSAGE

The study unveils Si's regulatory influence by regulating DEGs, TFs, and TRs. Further bHLH subfamily and auxin transporter pathway elucidates the mechanisms enhancing root development and nodulation. Soybean is a globally important crop serving as a primary source of vegetable protein for millions of individuals. The roots of these plants harbour essential nitrogen fixing structures called nodules. This study investigates the multifaceted impact of silicon (Si) application on soybean, with a focus on root development, and nodulation employing comprehensive transcriptomic analyses and gene regulatory network. RNA sequence analysis was utilised to examine the change in gene expression and identify the noteworthy differentially expressed genes (DEGs) linked to the enhancement of soybean root nodulation and root development. A set of 316 genes involved in diverse biological and molecular pathways are identified, with emphasis on transcription factors (TFs) and transcriptional regulators (TRs). The study uncovers TF and TR genes, categorized into 68 distinct families, highlighting the intricate regulatory landscape influenced by Si in soybeans. Upregulated most important bHLH subfamily and the involvement of the auxin transporter pathway underscore the molecular mechanisms contributing to enhanced root development and nodulation. The study bridges insights from other research, reinforcing Si's impact on stress-response pathways and phenylpropanoid biosynthesis crucial for nodulation. The study reveals significant alterations in gene expression patterns associated with cellular component functions, root development, and nodulation in response to Si.

Rhizophagus irregularis and Azotobacter chroococcum Uphold Eggplant Production and Quality under Low Fertilization

Microorganisms are essential parts of soil and play an important role in mediating many processes and influencing plant health. Arbuscular mycorrhizal fungi (AMF) and nitrogen-fixing bacteria (NFB), the most common of such microorganisms, can benefit plants by enhancing the nutrient-absorbing ability of roots through bio-inoculation, also called biofertilization. Different methods have been tested and proven to be effective in the enhancement of soil nutrient availability. However, the effects of increased application of biological methods with minimal chemical fertilizers are still inconsistent. In this 2-year of fixed-point greenhouse test, we aimed to evaluate the impact of AMF (Rhizophagus irregularis) and/or NFB (Azotobacter) on growth, quality, and yield of eggplants under different N levels. Data showed that biofertilizer application with reduced chemical fertilizer had the highest impact on eggplant performance and yield. Indeed, low chemical fertilizers combined with adequate amounts of biofertilizers produced a higher plant height, length and width of leaves, dry matter, number of fruits per plant with better morphology, total yield per plant, and total soluble solids (TSS), suggesting that the use of Azotobacter and R. irregularis as biofertilizers could substantially reduce the use of chemical fertilizers without impairing the quality and yield of eggplant.

Response of Yam (Dioscorea alata) to the Application of Rhizophagus irregularis and Potassium Silicate under Salinity Stress

Yam (Dioscorea alata) is a tropical plant that is considered critical for food security. The use of high fertilizer, low soil fertility, and insect pest infestation reduce yam tuber yield and quality. The present study was performed to determine the effect of potassium silicate and arbuscular mycorrhizal fungi (AMF) on yam cultivated under salinity stress. This study revealed that the combination of Rhizophagus irregularis (AMF) and Potassium silicate was more effective than their individual application on yam and were beneficial for overall analyzed characters. We observed the days to emergence and the average days to first leaf emergence decreased by 33.46% and 26.78%, respectively, the number of leaves increased by 45.23%, number of sprouts per seed tuber by 50%, vine length by 60.8%, vine length at harvest by 40.53%, the average leaf width by 53.79%, petiole length by 31.74%, tuber length by 43.84%, average diameter of tuber by 56.58%, and average number of tuber per vine by 46.15% in T5 treated plants. We also recorded that starch content increased by 21.89%, ascorbic acid by 61.51%, average moisture by 8.36%, TSS by 50%, and total sugar by 69.53% in T5 treated plants. The total phenol was found to be 1.53% higher in T3 applied plants, while the dry matter was 36.37% higher in T5 treatment. Furthermore, the enzymatic evaluation of MDA in leaves was found to be enhanced by 142% in T2. The enzyme 8-OHdG from the leaves sample was reported to be increased after T5 by 621.15%. Moreover, the amount of CAT was higher by 53.46% in T2 treated plants. Likewise, the amount of enzyme SOD and POX in leaves of D. alata enhanced by 30.91% and 51.15% T2 treatments respectively.