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Uppermost internode length (UIL) and panicle exsertion are two important traits that contribute significantly to increased yield in rice. The present study was conducted using recombinant inbred lines (RILs) comprising 201 lines derived from RTN10B and IRG213. These RILs were evaluated at three different locations— Delhi, Karnal, and Aduthurai. We report the mapping of quantitative trait loci (QTLs) for uppermost internode length and the panicle exsertion ratio (PER), as well as QTLs for plant height (PH), tiller number, length of the second internode, length of the third internode, length from the flag leaf to the panicle tip (PFL), and panicle length (PL). Mapping was performed using a custom microsatellite linkage map constructed for the population, having a total span of 2077.1 cM with 104 markers. A total of 22 QTLs were identified for various traits, among which 19 were found distributed in four hotspots. A total of 11 major effect QTLs and 11 minor effect QTLs were identified for various internode length-related traits. Among the four QTLs identified for PFL, three QTLs—qPFL1.1, qPFL1.2, and qPFL2.1—co-localized with previously reported QTLs, while qPFL8.1 was a novel QTL. A major QTL hotspot was identified on chromosome 1, located at the marker interval of RM12055-RM320. The size of the major QTL hotspot on chromosome 1 was 1.4 Mb and contained a total of seven HEs for PER, PFL, PH, PL, UIL, SIL, and TIL. Based on the in-silico analysis of the major QTL hotspot on chromosome 1, we identified 15 putative candidate genes associated with internode length- and panicle-related traits. Furthermore, narrowing the genomic region through the fine mapping of the marker intervals facilitated the identification of candidate genes to enable more precise marker-assisted selection for uppermost internode length and panicle exsertion.

In a field trial at the College Farm, NAU, Navsari (Gujarat), evaluated four main plot treatments (T1: Green gram, T2: Cowpea, T3: Dhaincha, and T4: Fallow), which were grown during the summer with three replications following a randomized block design (RCBD). Green gram and cowpea were incorporated into the soil after harvest, but dhaincha was incorporated at 50% flowering. During Kharif, each main plot was split into six smaller plots with different treatments: W1 was 100% RDF, W2 was 75% RDF, W3 was 50% RDF, W4 was 75% RDF + 25% N from FYM, W5 was 50% RDF + 50% N from FYM, and W6 was no fertilizer. The results of all 24 treatment combinations were repeated three times in a split-plot design. The analysis showed significant growth, yield attributes, grain yield, and straw yield of rice in dhaincha-incorporated plots (T3), fb greengram (T1), and cowpea (T2) plots using 100% RDF, while fallow (T4) with no fertilizer application recorded significantly lower values. SPAD meter readings of rice were higher in W4 (75% RDF + 25% N from FYM), which was at par with W1 in dhaincha-incorporated plots (75% RDF + 25% N from FYM) (W4). However, applying no fertilizer (W6) resulted in lower values. The total uptake of nitrogen and phosphorus in rice was highest when it was grown in dhaincha incorporated (T3), followed by green gram (T1), cowpea (T2) incorporated plots with the usage of 100% RDF (W1) and 75% RDF + 25% N from FYM (W4), and lower values were recorded in fallow + no fertilizer treatment (T4W6). Our study revealed that incorporating summer legumes before planting rice significantly increased plant height, tillers, grain and straw yield, and total uptake. With dhaincha, inclusion has shown a greater advantage.

Adzuki bean, an underutilized grain legume, has a significant potential for enhancing food and nutritional security. The main obstacles to developing new cultivars and promoting the adzuki bean as a mainstream pulse crop are a lack of awareness about its potential and insufficient information on crop its genetic diversity. Here, we aimed to explore the untapped potential of adzuki bean germplasm by evaluating its agro-morphological traits and diversity at the molecular level and also to identify trait-specific germplasm by utilizing 100 adzuki bean accessions conserved in the Indian National Genebank. Significant variations was recorded for the morphological traits and identified promising accessions exhibiting desirable traits, such as early flowering (IC341945, EC340257 and EC340283), number of primary branches (IC341945 and IC469175), number of clusters per plant (EC000264, IC167611 and IC341939), number of pods per plant (IC469175, EC34264, EC000264), early maturity (EC340283; EC120460; IC341941) and number of seeds per pod (EC340240, IC455396 and IC341955). Molecular characterization of diverse accessions using 22 polymorphic SSR markers identified a total of 50 alleles, with a mean of 2.27 alleles per loci. The polymorphic information content (PIC) ranged from 0.03 to 0.46, indicating informativeness of markers in distinguishing diverse accessions. Further, the gene diversity among the accessions ranged from 0.03 to 0.57 with a mean of 0.19. Population structure analysis grouped the accessions into three genetic groups, supported by Principal Coordinate Analysis (PCoA) and a phylogenetic tree. Additionally, Analysis of Molecular Variance (AMOVA) confirmed a substantial genetic diversity among the adzuki bean accessions. Thus, the combined assessment of agro-morphological traits and molecular markers effectively distinguished adzuki bean accessions and provided valuable insights in understanding untapped variation at both morphological and molecular levels. The promising accessions identified in the study hold potential for integration into legume improvement programs through introgression breeding, contributing to the development of adzuki bean varieties with target trait.

Maize is an important food, feed, fodder and industrial crop in addition to being a valuable source of micronutrients. Phytic acid (PA), an anti-nutritional factor in maize, makes crucial minerals inaccessible to monogastric animals. The low phytic acid-1 (lpa1) gene located on chromosome-1S is 7292 bp long with 11 exons, and the recessive lpa1-1 allele reduces the accumulation of PA thereby enhances the bioavailability of essential minerals in maize kernels. Here, we characterized the full-length Lpa1 gene sequence in three mutants (lpa1-1) and seven wild-type (Lpa1) maize inbreds. Sequence analysis revealed 607 polymorphic sites across Lpa1 sequences, indicating wide variability for Lpa1 among the inbreds. Further, SNP from “C” to “T” differentiated wild-type and mutant-type alleles at 1432 amino acid position. Gene-based diversity among 48 diverse maize inbreds using 15 InDel markers revealed the formation of 42 distinct haplotypes; six of which (Hap6, Hap16, Hap17, Hap19 Hap27 and Hap31) were shared by more than one genotype. The number of exons in Lpa1 ranged from 11–19 among maize genotypes and 6–14 among 26 orthologues. Major functional motifs of Lpa1 detected were ATP-binding Cassette (ABC) transporter trans-membrane region and ABC transporter. Phylogenetic tree using nucleotide and protein sequences revealed a closer relationship of maize Lpa1 sequences with Sorghum bicolor, Panicum hallii, Setaria italica and S. viridis. This study offered newer insights into the understanding of the genetic diversity of the Lpa1 gene in maize and related crop-species, and information generated here would further help in exploiting the lpa1 mutant for the enhancement of nutritional value in maize kernels.