Flash flooding (FF) along with bacterial blight (BB) outbreak are very destructive for rice production in the rainfed shallow-lowland (RSL) ecosystem. The presence of dynamic Xoo races with varying levels of genetic diversity and virulence renders their management extremely challenging under RSL. In this context, the marker-assisted improvement of plant resistance/tolerance has been proven as one of the most promising strategies towards the development of sustainable cultivars. The present study demonstrates the marker-assisted introgression of the submergence tolerant (Sub1) and three bacterial blight resistant genes (Xa21 + xa13 + xa5) into the genetic background of Hasanta, a long duration popular rice variety in the eastern coastal region of India. The rice genotypes, Swarna Sub1 (carrying Sub1) and IRBB66 (carrying Xa21 + xa13 + Xa7 + xa5 + Xa4) had maximum genetic similarity (0.84 and 0.73, respectively) with Hasanta; recurrent parent (RP) was used as donor. The forward analysis of target genes in F1s, IC1F1s and backcross (BC) generations was performed by linked/genic markers (Sub1bc2; pTA248, xa13prom and RM122), whereas background recovery of RP in each BC and segregating generations was performed utilizing 108 hypervariable SSR markers. Intervened speed breeding (SB) strategy and intensive phenotyping could lead the development of near isogenic lines (NILs) as to the RP in all basic traits. The performance of the near isogenic lines (NILs, BC2F3 and BC2F4), HS 232-411-391-756-37, HS 232-411-391-809-8, HS 232-411-391-756-18, HS 110-224-197-10-36, HS 232-411-391-809-81, HS 110-224-197-10-41 and HS 232-411-391-809-63 establishes the utility of marker-assisted backcross-breeding (MAB) and SB in accelerated trait introgression. The introgressed lines carrying Sub1 + Xa21 + xa13 + xa5 showed 76% to 91% survival under 14 days of submergence and durable BB resistance (percent disease index-PDI of 2.68 ± 0.26 to 6.22 ± 1.08 and lesion length, LL of 1.29 ± 0.12 to 4.2 ± 0.64 cm). Physiological analysis revealed that improved NILs, carrying Sub1 gene conquered adaptive physiological modulations, had reduced the consumption of soluble sugar and the degradation of total chlorophyll contents (TCC), and an enhanced level of Alcohol Dehydrogenase activity (ADH) and proline accumulation in all submergence regimes. The pyramided lines attained complete product profile of RP, that will contribute to sustainable rice production under RSL, particularly in the coastal region that has substantial acreage under the variety Hasanta.

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A field experiment was conducted at the instructional farm of Krishi Vigyan Kendra Jajpur, Odisha during 2016 to study the effect of integrated nutrient management on disease and pest incidence and yield of okra (Abelmoschus esculentus (L.) Moench) variety Pusa A-4. From the experiment it was observed that treatment T7 [ RDF(75%)+ (25%) neem oil cake] has significant effect on disease incidence and pest population by reducing incidence of YVMV from 32.42% to 19.56%, jassid population from 11.57 to 6.53 per three leaves,mite population from 11.98 to 8.11 per three leaves, white fly population from 13.61 to 6.64 per three leaves and fruit borer from 17.94 % to 7.94 %. Maximum number of fruits per plant 15.02 was recorded in T7. Fruit yield per hectare varied significantly and was maximum with T7 (10.49 ton) and was minimum with T11 (7.30 ton). T7 (10.49 ton) and T5 (9.85 ton) and T10 (9.65 ton) were at par with each other. Combined use of 75 % RDF as inorganic fertilizer with 25 % RDF through neem oil cake (T7) recorded highest gross income of Rs.1,45,770/-, net income Rs.85,458 /-per hectare and maximum benefit cost ratio 2.42.

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The present investigation was undertaken to estimate the combined effects of hybridization and Ethyl Methane sulfonate (EMS) on variability of polygenic traits associated with productivity in F1M1 generation of sesame crop. Three popular and well adapted sesame varieties were crossed and three nonreciprocal crosses were made. These F1s seeds were divided into two lots and one lot from each cross were used for EMS treatment. F1s seeds of each cross were presoaked separately in distilled water overnight followed by treating with 0.5 percent freshly preparer EMS solutions for 3 hours. Seed s of total nine populations (three EMS treated populations "F1 1 M1", three respective crosses as controls "F1s" and three parents) were shown in a randomized block design (RBD) with 3 replications during the summer season, 2017. Observations were recorded on four polygenic traits and statistical analysis like ANOVA of mean, standard deviation and CV was carried out and the significant differences among various treatments were tested by ' F' and t -tests. Reduced mean and increased standard deviation was observed for plant height whereas increased mean and standard deviation was observed for number of capsules per plant and seed yield per plant in EMS treated F1 1 M1s. Increased in variability in mutant populations for above characters might be due to breakage of linkage between favorable and unfavorable genes. Three F1M1 populations used in this study showed differential sensitivity with respect to different quantitative characters. The changes in different polygenic traits of mutant populations than respective controls must have arisen through induced micro-mutations. The relative magnitudes of genetic change in the hybrids as a result of chemical mutagen would be better known from analyses in later generations.

The value of combining hybridization and mutagenesis in sesame was examined to determine if treating hybrid sesame plant material with mutagens generated greater genetic variability in four key productivity traits than either the separate hybridization or mutation of plant material. In a randomized block design with three replications, six F2M2 varieties, three F2varieties, and three parental varieties were assessed at Odisha University of Agriculture and Technology, Bhubaneswar, Odisha, India. The plant characteristics height, number of seed capsules per plant, and seed yield per plant had greater variability in the F2M2 generation than their respective controls (F2), however, the number of primary branches per plant varied less than in the control population. The chances for trait selection to be operative were high for all the characteristics examined except the number of primary branches per plant, as indicated by heritability estimates. Increases in the mean and variability of the characteristics examined indicted a greater incidence of beneficial mutations and the breakdown of undesirable linkages with increased recombination. At both phenotypic and genotypic levels strong positive correlations between both primary branch number and capsule number with seed yield suggest that these traits are important for indirect improvement in sesame seed yield. As a result of the association analysis, sesame seed yield and its component traits improved significantly, which may be attributed to the independent polygenic mutations and enlarged recombination of the polygenes controlling the examined characteristics. Compared to the corresponding control treatment or to one cycle of mutagenic treatment, two cycles of mutagenic treatment resulted in increased variability, higher transgressive segregates, PTS mean and average transgression for sesame seed yield. These findings highlight the value of implementing two EMS treatment cycles to generate improved sesame lines. Furthermore, the extra variability created through hybridization may have potential in subsequent breeding research and improved seed yield segregants may be further advanced to develop ever-superior sesame varieties.