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Aim: To determine the influence of gestation and weight on the development of protective anti‐HB levels and geometric mean titres after three doses of HBV vaccine and to ascertain the need for a fourth dose in low birthweight infants. Methods: Hepatitis B vaccine (Enivac HB, Panacea Biotec Ltd., India) was given to 82 preterm (PT) and 60 term intrauterine growth‐retarded (T‐IUGR) infants at birth and at 6, 10 and 14 wk of life. Results: Protective anti‐HB levels (>10 mIU/ml) were reached in 86.6% (71/82) of PT infants and 96.7% (58/60) of T‐IUGR infants after three doses of HBV vaccine (p= 0.044). The odds of having a protective response after the third dose of HBV vaccine was 1.25 (95% CI 1.02–1.53) with every one‐week increase in gestation (p= 0.032). Birthweight was not associated with the development of a protective immune response. After the third dose, only 66.7% (8/12) of the PT infants whose mothers had anti‐HB antibodies, developed protective anti‐HB levels compared with 90% (63/70) of those with no maternal antibodies (p= 0.028). In PT infants after the fourth dose, there was a significant increase in the proportion of infants with protective antibody levels (8.6%, 95% CI 0.6–16.6%) among those with no maternal antibodies and 12.2% overall (95% CI 6.0–21.3) (p= 0.031 to 0.002) over that reached with the third dose. Administration of the fourth dose to T‐IUGR infants did not confer such a benefit. Conclusion: In HBV‐endemic areas, PT infants, irrespective of their birthweights, may benefit from an additional dose of hepatitis B vaccine in a schedule starting at birth. This approach will prevent vertical transmission and bring their immune response up to par with term infants. Term intrauterine growth‐retarded infants should be vaccinated as per the schedule recommended for normal term infants. However, studies in other settings with different vaccine formulations and a longer follow‐up period will be required before this strategy can be practised more widely.

DRR Dhan 57 [IET 26171 (RP 5601-283-14-4-1)], an aerobic rice variety was developed from BPT5204/ Azucena cross combination. It was evaluated in AICRIP multi-location aerobic rice trials during the wet seasons of 2016 to 2020. DRR Dhan 57 consistently outperformed the check varieties in Eastern Zone (Zone III) and Central Zone (Zone V) with a mean grain yield of 4782 kg/ha, which is 13%, 17% and 16 % higher than the National, Zonal and Local checks, respectively. In addition, it exhibited moderate resistance to leaf blast and Neck blast; and to gall midge and rice thrips, and moderate resistance to planthoppers and whorl maggot. DRR Dhan 57 has a mid-early duration of 120 days (seed to seed) and possesses desirable grain and cooking quality parameters. It was released for cultivation in aerobic ecosystems of Jharkhand (Zone III), and Chhattisgarh (Zone V) states through Central Sub-committee on Crop Standards, Notification and Release of Varieties for Agricultural Crops; vide S.O. 8(E) dated 24th December 2021[CG-DL-E-04012022-232406].

Rice false smut disease is gaining importance because of its impact on the grain yield and its toxin production ability. Fifty-eight isolates of Ustilaginoidea virens were collected from different rice-growing regions of India. DNA of U. virens was isolated by the CTAB method and fifty ISSR primers were screened for molecular variability studies. Twelve primers viz., UBC series 807, 808, 809, 810, 811, 812, 834, 835, 836, 840, 841, and 842 were selected to study the genetic variability. Different parameters of tested primers viz., heterozygosity (Hn), polymorphism information content (PIC), effective multiplex ratio (EMR), marker Index (MI), and resolving power (RP) were calculated. Primers UBC 812 and UBC 809 recorded maximum heterozygosity (Hn). The PIC values ranged from 0.10 to 0.27 and UBC 807 recorded the maximum value of 0.27. The EMR value varied from 6.75 to 24.0, Similarly, UBC 807 recorded the highest value of MI (24) and RP (8.55). A dendrogram was generated using the DARwin software (version 6.0.21A) based on the unweighted neighbor-joining cluster method. All the fifty-eight U. virens isolates were grouped into three major clusters. Clusters I and II had 21 and 35 U. virens isolates respectively. Cluster III had only two isolates. The isolates showed genetic variations and there was no specific grouping based on the geographical distance.

DRR Dhan 54 [IET 25653 (RP 5943-421-16-1-1-B)] was released for aerobic system of cultivation in water limiting areas of Zone II (Haryana), III (Odisha, Bihar and Jharkhand), VI (Gujarat) and VII (Telangana) through Central Sub-committee on Crop Standards, Notification and Release of Varieties for Agricultural Crops vide S.O. 500(E) dated 29th Jan 2021 [CG-DL-E-03022021-224901]. DRR Dhan 54 was developed from the cross of RP 5124-11-4-3-2-1/IR 78877-208-B-1-1. It was tested in Aerobic trials in AICRIP during 2015-2018 and found to be a top ranking entry on overall basis in three years (2018, 2016 and 2015). Across multiple zones, DRR Dhan 54 ranked 1st with 15.8%, 4th with 12% and 5th with 17% yield advantage over the BVC in 2018, 2016 and 2015, respectively indicating its wider adaptability and yield stability. It has desirable grain quality traits in terms of high HRR%, intermediate AC% and multiple pest and disease resistance.