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An experiment was conducted during rainy (kharif) seasons of 2019 and 2020 at the research farm of ICAR Indian Agricultural Research Institute, New Delhi to screen 90 genotypes of scented short grained rice (Oryza sativa L.) for Fusarium fujikuroi resistance. Genotypes Kankjeer A, Lectimanchi-A, Sumati, Pankhali-203, GR-102, NWGR- 3042, Geetanjali, R 1432-261-105-2-1-2, Khaskani, C-4-63-G, Calrose 76, JJ 92, Koliha, Hari Shankar, Kusuma, IR 74717-3-3-1-3, IR 74725-115-3-3-3, IR 74728-134-1-1-3, Hansraj, Anterved and GAR-1 were identified as moderately resistant with the disease rating of 3 in both the years of evaluation. Further, a set of genotypes with different disease response was evaluated for different parameters including root length, shoot length, number of fibres/threads in roots, days of symptom appearance and area under disease progress curve (AUDPC). Disease severity was observed to be significantly correlated (r = 1.0) with AUDPC and days required for the symptom appearance (r = 0.95). Results indicated that apart from the disease severity, AUDPC could also be considered as a one of the component for the bakanae disease resistance. The resistant sources identified in the present study can be utilized in rice breeding programme against bakanae disease.

Bakanae disease caused by Fusarium fujikuroi is an emerging disease of rice causing losses in all rice-growing regions around the world. A BC2F2 population was developed by backcrossing the recurrent parent Pusa Basmati 1121 (PB1121) with the recombinant inbred line RIL28, which harbors a major quantitative trait locus (QTL) governing resistance to bakanae, qBK1.2. MassARRAY-based single-nucleotide polymorphism (SNP) assays targeting the genomic region of qBK1.2 helped in fine mapping the QTL to a region of 130 kb between the SNP markers rs3164311 and rs3295562 using 24 recombinants. In-silico mining of the fine-mapped region identified 11 putative candidate genes with functions related to defense. The expression analysis identified two significantly differentially expressed genes, that is, LOC_Os01g06750 and LOC_Os01g06870, between the susceptible genotype PB1121 and the resistant genotypes Pusa1342 and R-NIL4. Furthermore, the SNPs identified in LOC_Os01g06750 produced minor substitutions of amino acids with no major effect on the resistance-related functional motifs. However, LOC_Os01g06870 had 21 amino acid substitutions, which led to the creation of the leucine-rich repeat (LRR) domain in the resistant genotype Pusa1342, thereby making it a potential candidate underlying the major bakanae-resistant QTL qBK1.2. The markers used in the fine mapping program are of immense utility in marker-assisted breeding for bakanae resistance in rice.

In present study, different varieties of chrysanthemum (Chrysanthemum × morifolium Ramat) were screened for total carotenoids, phenolic content and antioxidant activities. Among the genotypes studied, variety Jubilee (32.82 mg/100g) exhibited high total carotenoids followed by varieties Haldighati (26.71 mg/100 g), Little Orange (22.25 mg/100g), Liliput (20.77 mg/100g) and Star Yellow (19.21 mg/100g). Variety Jubilee also showed highest antioxidant activities of carotenoids {CUPRAC-Cupric reducing antioxidant capacity (149.44 μmol trolox/g), FRAP- Ferrous reducing power (40.09 %), DPPH radical scavenging activity (11.24%)}. The total phenolic content varied from 1.26 mg GAE/g (Ram Lal Dada) to 31.14 mg GAE/g (Jubilee) on fresh weight basis. Further, five promising varieties having high carotenoids, were quantified for lutein and β-carotene using High Performance Liquid Chromatography (HPLC). Highest lutein content was found in variety Jubilee (19.90 μg/g) followed by varieties Haldighati (8.67 μg /g), Liliput (4.77 μg /g), Star Yellow (3.93 μg /g) and Little Orange (3.69 μg/g). Highest β-carotene content was found in Little Orange (5.51μg/g) followed by the varieties Haldighati (2.04 μg /g), Jubilee (1.77 μg /g), Liliput (0.54 μg /g) and Star Yellow (0.50 μg/g). A high correlation between carotenoids, total phenolic and antioxidant activities was observed. Variety Sadwin Yellow showed highest total carotenoid (0.48 mg/g) in leaves, whereas chlorophyll a and total chlorophyll was highest in variety Punjab Anmol (1.32 mg/g, 1.56 mg/g) and high chlorophyll b in variety Pusa Aditya (0.28 mg/g).

PCR amplification and detection of GC rich sequences in DNA is a challenge due to formation of secondary structures which resist denaturation, thereby stalling Taq DNA polymerases as well as affecting primer annealing. Presently, high fidelity Taq DNA polymerase is used for amplifying long and GC-rich fragments, while dimethyl sulfoxide (DMSO) has also been suggested as an additive in Polymerase Chain Reaction (PCR) mix to avoid formation of secondary structures in templates containing high GC content. In the present study, the amplification efficiency of normal Taq DNA polymerase with 5% DMSO as compared to high fidelity Taq DNA polymerase has been applied for better amplification of fragments with high GC content of sd1 gene in rice. Normal Taq DNA polymerase with 5% DMSO displayed better and reproducible results as compared to platinum DNA polymerase for the amplification of gene sd1, thereby successfully detecting the dominant wild type allele governing tall plant height from the recessive semi-dwarf allele. There were no adverse effects of 5% DMSO in PCR amplification and the amplified fragments improved significantly indicating the improvement in amplification efficiency. The modified PCR protocol including DMSO provides a cost effective and cheaper alternative for reliable assessment of the genomic differences in GCrich regions of the gene. This will help in eliminating the need for costly high fidelity Taq DNA polymerase, thereby helping in economizing marker assisted selection.

Basmati rice is known for its extra-long slender grains, exceptional kernel dimensions after cooking, high volume expansion, and strong aroma. Developing high yielding Basmati rice varieties with good cooking quality is a gigantic task. Therefore, identifying the genomic regions governing the grain and cooked kernel dimension traits is of utmost importance for its use in marker-assisted breeding. Although several QTLs governing grain dimension traits have been reported, limited attempts have been made to map QTLs for grain and cooked kernel dimension traits of Basmati rice. In the current study, a population of recombinant inbred lines (RIL) was generated from a cross of Sonasal and Pusa Basmati 1121 (PB1121). In the RIL population, there was a significant positive correlation among the length (RRL: rough rice length, MRL: milled rice length, CKL: cooked kernel length) and breadth (RRB: rough rice breadth, MRB: milled rice breadth and CKB: cooked kernel breadth) of the related traits, while there was significant negative correlation between them. QTL mapping has led to the identification of four major genomic regions governing MRL and CKL. Two QTLs co-localize with the earlier reported major gene GS3 and a QTL qGRL7.1, while the remaining two QTLs viz., qCKL3.2 (qMRL3.2) and qCKL4.1 (qMRL4.1) were novel. The QTL qCKL3.2 has been bracketed to a genomic region of 0.78 Mb between the markers RM15247 and RM15281. Annotation of this region identified 18 gene models, of which the genes predicted to encode pentatricopeptides and brassinosteroid insensitive 1-associated receptor kinase 1 precursor may be the putative candidate genes. Furthermore, we identified a novel QTL qKER2.1 governing kernel elongation ratio (KER) in Basmati rice.

Direct-seeded rice (DSR) is gaining popularity among farmers due to its environmentally safe and resource-efficient production system. However, managing the rice root-knot nematode (RRKN), Meloidogyne graminicola, remains a major challenge in DSR cultivation. Developing genetic resistance is a pragmatic and effective approach compared to using hazardous pesticides. Pusa Basmati 1121 (PB1121) is the most popular Basmati rice variety, but it is highly susceptible to RRKN. In contrast, Phule Radha (PR) has shown highly resistant reaction to RRKN, as reported in our earlier study. We generated an F2:3 population from the cross of PB1121/PR and evaluated it for RRKN resistance-related traits under artificial inoculation conditions. The distribution pattern of traits in the F2:3 population indicated that resistance may be governed by a few major-effect genes and many minor-effect genes. The molecular markers reported to be associated with QTLs governing RRKN resistance traits were used to test in the current population. Although the simple linear regression identified significant associations between the markers and RRKN resistance-associated traits, these associations were spurious as the LOD score was below the threshold limit. This indicates that PR possesses novel genomic regions for resistance to RRKN as it does not possess any of the earlier reported QTLs. [ABSTRACT FROM AUTHOR]

The association of parental divergence based on simple sequence repeats (SSR) markers and heterosis in 96 rice (Oryza sativa L) hybrids was investigated for yield and component traits under four environments. Hybrids were derived from four cytoplasmic male sterile (CMS) lines and 24 iso-cytoplasmic restorers (ICR). The genetic distance (GD) and heterosis were significantly correlated for the number of productive tillers per plant (0.537) and panicle length (0.386) in Delhi under early sowing. Under late sowing, negative correlations were also observed (-0.435, -0.401) with pollen fertility percentage. The GD and heterotic performance of hybrids were significantly correlated for panicle length (r=0.35) and number of effective tillers per plant (r=0.51). At Karnal, significant association between GD and hybrid grain yield (0.615) was observed. Besides, insignificant correlations were observed for some other traits at different locations. The non-significant correlations indicated the need of employing trait related functional/ gene based markers as well as using more abundant markers for accurately predicting the hybrid performance.

Abstract Pusa Basmati 1121 (PB 1121) is a landmark Basmati rice variety having Basmati quality traits introgressed from traditional Basmati varieties such as Basmati 370 and Type 3. It was released for commercial cultivation in 2003. It possesses extra-long slender milled grains (9.00 mm), pleasant aroma, and an exceptionally high cooked kernel elongation ratio of 2.5 with a cooked kernel length of up to 22 mm, volume expansion more than four times, appealing taste, good mouth feel and easy digestibility. Owing to its exceptional quality characteristics, it has set new standards in the Basmati rice market. The cumulative foreign exchange earnings through export of PB 1121 since 2008 have been US$ 20.8 billion, which has brought prosperity to millions of Basmati farmers. During 2017, the farmers cultivating PB 1121 earned on an average US$ 1400/ha as against US$ 650/ha cultivating traditional Basmati, making it a highly profitable enterprise. Currently, PB 1121 is grown in ~ 70% of the total area under Basmati rice cultivation in India. It is the most common Basmati rice variety in rice grain quality research for developing mapping populations, genetic analyses and molecular mapping of Basmati quality traits. Additionally, it has been widely used in the Basmati rice breeding program across India, because of its superior quality attributes. This article presents an account of development of PB 1121, its major characteristic features and its flagship role in heralding a Basmati rice revolution. The prospective role of PB 1121 in Basmati rice improvement and future Basmati rice research as a whole is also presented.

The present investigation was carried out during kharif 2017 at ICAR-IARI, New Delhi to assess the extent of genetic variability, heritability and genetic advance in eggplant using F2 population from a cross of Pusa Safed Baingan 1 × Pusa Uttam. A total of 168 F2 plants were characterized for morphological, and fruit traits and subjected to statistical analysis. Wide ranges of variations were observed for plant height (44.23 cm to 84.36 cm), fruit length (4.17 cm to 13.17 cm), fruit diameter (3.17 cm to 11.53 cm), fruit weight (15.20 g to 248.30 g) and total anthocyanin content (0.01 to 118.12 mg/100 g FW). High PCV and GCV (>20%) were observed for plant height, fruit weight and anthocyanin content. The highest heritability (74.09%) was recorded for fruit diameter indicating wide scope for improvement through selection of this trait. A total of 32 transgressive segregants were observed for fruit weight ranging from 165.30 g to 248.30 g and these can be selected further from F2. Fruit weight was found to be positively and significantly correlated with plant height (0.09), fruit length (0.53), fruit diameter (0.76) both at genotypic and phenotypic level. The skewness of all the five traits except total anthocyanin was less than 1 which suggests that these traits followed normal distribution, whereas anthocyanin followed discrete distribution. The exploration of genetic variability in the available segregating population may be utilized for effective selection of superior plant type for developing a variety.

Homozygous Golden Rice lines developed in the background of Swarna through marker assisted backcross breeding (MABB) using transgenic GR2-R1 event as a donor for the provitamin A trait have high levels of provitamin A (up to 20 ppm) but are dwarf with pale green leaves and drastically reduced panicle size, grain number and yield as compared to the recurrent parent, Swarna. In this study, we carried out detailed morphological, biochemical and molecular characterization of these lines in a quest to identify the probable reasons for their abnormal phenotype. Nucleotide blast analysis with the primer sequences used to amplify the transgene revealed that the integration of transgene disrupted the native OsAux1 gene, which codes for an auxin transmembrane transporter protein. Real time expression analysis of the transgenes (ZmPsy and CrtI) driven by endosperm-specific promoter revealed the leaky expression of the transgene in the vegetative tissues. We propose that the disruption of OsAux1 disturbed the fine balance of plant growth regulators viz., auxins, gibberellic acid and abscisic acid, leading to the abnormalities in the growth and development of the lines homozygous for the transgene. The study demonstrates the conserved roles of OsAux1 gene in rice and Arabidopsis.