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Marigold (Tagetes spp.) belongs to family Asteraceae, native to Mexico, is one of the most important flower crop grown commercially in different parts of India. The application of haploid techniques as anther culture can considerably accelerate marigold breeding programmes by providing homozygous doubled haploid (DH) lines for F1 hybrid seed production. Therefore, the objective of the present investigation was to study the effect of growth regulators for in vitro regeneration in both African marigold and French marigold genotypes viz., Pusa Basanti Gainda and Pusa Arpita, respectively for haploid induction. Among the different treatments tested for callus induction, anthers cultured on MS medium supplemented with 1.0 mg/l BAP + 1.0 mg/l 2,4-D + 45 g/l sucrose significantly induced highest (38.74%) callus in the shortest period of time (16 days). Among two genotypes tested, embryogenic callus induction (27.70%) was significantly higher in Pusa Arpita over Pusa Basanti Gainda (23.37%). Among the different regeneration treatments, the highest adventitious shoot bud induction (13.32%), maximum (1.09) number of buds/callus in shortest duration (19.47 days) was observed in anther derived callus cultured on MS medium supplemented with 2.0 mg/l BAP + 0.5mg/l NAA + 30 g/l sucrose. Among two genotypes evaluated for shoot bud induction, maximum (3.81%) regeneration was recorded in Pusa Arpita over Pusa Basanti Gainda (2.90%). In French genotype, the whole regeneration process was completed in 30 days whereas in African genotype it took nearly 40 days. This rapid regeneration system from anthers is highly useful in inducing haploids and di-haploids in African and French marigold lines, respectively.

Un-rooted cuttings of chrysanthemum varieties Pusa Chitraksha, Pusa Anmol and Basanti were treated with Electron Beam (EB) radiation (20 Gy and 30 Gy) with an objective of inducing variability and evaluated at ICAR-DFR, Pune during 2020. A gradual and significant reduction in vital plant growth parameters was observed with increase in doses. Influence of EB radiation (at 30Gy) on plant height (-34.55%), plant spread (-28.60%), internode length (-39.04%), leaf length (-26.95%), leaf width (-29.28%), number of flowers per plant (-23.28%) and for flower diameter (-24.80%) in comparison to control was recorded. Delay in days to bud initiation and flowering at higher dose (30 Gy) were 13.47 days and 17.33 days, respectively over control. Among the varieties, Pusa Chitraksha was found superior for most of the vegetative growth and flowering parameters. However, it exhibited delay in bud initiation (95.80 days) and flowering (118.0 days). The trend is similar for other two varieties at higher dose. In the interaction effect (Variety x EB dose), plant height (17.00 cm) was very less in variety Basanti at 30 Gy dose. Flower diameter (3.26 cm) was reduced with increased EB dose (30 Gy) in Pusa Aditya compared to control (5.24 cm). Pusa Chitraksha exhibited variation in flower colour (Magenta to white/ cream colour) and Pusa Aditya produced red colour flower at 30 Gy. Based on the study, it can be inferred that Electron Beam at 20-30 Gy had potential to create variation in chrysanthemum.

The present study was carried out at ICAR-IARI to standardize the protocol for screening of African marigold against saline stress under hydroponic system. Seedlings of African marigold cv. Pusa Narangi Gainda were grown under hydroponics system. They were treated with different levels of NaCl, viz. 0 mM 50 mM, 80 mM, 100 mM, 120 mM, 140 mM, 150 mM, 160 mM, 200 mM, after 7 days of transplanting to standardize the threshold level for the further rapid screening of germplasms at nursery stage. Observations on mortality, growth, morphological, physiological, biochemical parameters and tissue nutrient status were recorded and found to decrease with increasing in saline stress. Mortality in seedlings was not observed up to 80 m M NaCl stress. 150-160 mM qualified as the indicator concentration for the screening of African marigold genotypes based on the performance of marigold genotypes with regard to different morphological, physiological, biochemical parameters and tissue nutrient contents.

The present study was carried out to screen six promising varieties of chrysanthemum (Chrysanthemum morifolium Ramat.), viz. Pusa Chitraksha, Lalit, Pusa Aditya, Basanti, Himanshu, and Pusa Sona in MS (Murashige and Skoog) media supplemented with 0, 50, 100 and 150 mM/NaCl. As the concentration of NaCl increased, there was a corresponding decrease in shoot length, fresh weight, number of leaves and rooting percentage. Number of shoots per plant exhibited not much significant difference. Maximum reduction in plant growth was recorded in the variety Pusa Sona (60.60%) while minimum reduction was observed in variety Pusa Aditya (35.60%). The highest fresh weight was recorded in variety Pusa Aditya and lowest in the varieties Himanshu and Pusa Sona, when the medium was supplemented with 150 mM NaCl. Variety Pusa Sona (57.00%) had the maximum reduction in the number of leaves per plant and minimum was found in the variety Lalit (29.10%). Increasing salt stress had an adverse effect on rooting abilities of all the varieties. Under the control with no added NaCl, the rooting percentage was 100% among all the varieties. In medium supplemented with 150 mM/l NaCl, the maximum rooting was recorded in the variety Pusa Aditya (63.80%)) and Basanti (63.80%), whereas least was observed in the varieties Pusa Sona and Himanshu (22.00% and 41.80%, respectively).

Rose (Rosa × hybrida L.) is a commercially important ornamental crop which represents major share in world floriculture market and essential oil industry. In the present investigation, genetic diversity among 25 fragrant rose cultivars belonging to exotic and Indian origin was studied during 2016-17 at New Delhi. Thirty one SSR markers were used for characterization. A total of 96 alleles were identified among the genotypes with an average of 3.9 alleles per loci. Diversity among populations of different origins was analysed and it revealed that, cultivars from Indian origin exhibited higher diversity as compared to the selected cultivars from American and European origin. Effective number of alleles (Ne) and expected heterozygosity (He) values were more in Indian population (Ne=1.93, He=0.49) as compared to selected populations of American (Ne=1.45, He=0.45 and European (Ne=1.29, He=0.29) origin. Matching coefficient values ranged from 0.55– 0.86 indicated the existence of moderate variability among fragrant roses of different origin. Unweighted Pair Group Method using Arithmetic Mean (UPGMA) dendrogram clearly separated all the 25 genotypes into 7 different clusters. Cultivars, Rose Sherbet, Century Two Seedling and Brandy showed distant relationship with other cultivars and were found in three different individual clusters V, VI and VII respectively. The highest and lowest similarity values were noticed between the cultivar sets, Jawahar and Double Delight (86%) and Century Two Seedling and Brandy (55%). The molecular data generated in present investigation would be highly helpful for cultivar identification, conservation and for breeding fragrant roses.

An experiment was carried out to study the effect of growing media on growth, flowering and bulb production of LA hybrid and Oriental group of Lilium under protected condition. One cultivar from each group (Cv. Red Alert from LA hybrid group and cv. Avocado from Oriental group) were selected for the experiment. Fresh and healthy bulbs of each cultivar were planted in the different media composition and placed under protected condition. Results of present study showed that all the vegetative attributes of both the cultivars, viz. number of leaves, leaf area, leaf length, leaf width, plant height and stem diameter found optimistic in media containing cocopeat and vermiculite either with perlite or soil. Flowering traits, viz. number of days from visible bud to flowering, total number of buds, bud diameter, flower bud length, days taken to ¼, ½, ¾ colour bud break and full colour bud development, total number of flowers, diameter of flowers, duration of flowering and vase life of both the cultivar were also reported superior in media containing cocopeat and vermiculite either with perlite or soil. Similarly, bulb attributing charactersviz. number of bulblets, weight of bulb and bulblets, diameter of bulb and bulblets of both the cultivars were also recorded promising in media containing cocopeat and vermiculite either with perlite or soil. It could be concluded that media containing cocopeat and vermiculite either with soil or perlite observed to be the best substrate for growth, flowering and bulb production of Lilium.

Genetic diversity in roses is unparalleled to any other flower crops. A large number of rose species is grown all around the world. There is a rich wealth of indigenous rose species such as Rosa brunonii, R. macrophylla, R. moschata, R. spinossisima, R. rubiginosa, R. wichuraiana etc. are grown wild in India. They are the important source of genes responsible for various traits, viz. both biotic and abiotic stress tolerance, fragrance, perpetual flowering, hardiness which need to be protected for further use in breeding programs. Morphological markers or traits based species identification are best for visualization, reproducibility and easy to use, besides serving as a reality check for molecular studies. In this study, 31 rose species were characterized for 18 vegetative characters as per PPV FRA guidelines for DUS testing of rose. Genetic diversity of rose species was done based on dissimilarity calculation, hierarchical cluster analysis, linear discriminant analysis and principal component analysis using R software. R. banksiae - R. chinensis‘Viridiflora’ and R. banksiae - R. rubiginosa showed the highest diversity while R. brunonii and R. dumalis shows least diversity. Species were divided into five major clusters using hierarchical cluster analysis which was validated by linear discriminant analysis. Here, both Indian originating species R. brunonii and R. moschata fell into the same cluster while significant diversity noticed in R. damascena and R. wichuraiana. Results of principal component analysis follow a similar pattern as of dendrogram. R. banksiae was most distinctly placed which is well supported as only thornless species used in the study. Although no single morphological traits can be used to differentiate species, it is necessary to create a passport data for further studies.

Cordyline terminalis is an important ornamental plant used for its beautiful foliage as cut green. This plant prefers shade for optimum growth. The effect of different coloured shade nets (red, green, black, and white with 50% shading intensity) along with control (without shade net) on production and quality of Cordyline terminalis was studied. The effect of spectral control of light on physiology and vegetative development was evaluated at different crop growth stages. The results showed that plants grown under shade nets produce good quality foliage and biomass irrespective of colour. The cut greens grown under red and white shade nets were exposed to higher PAR and transmittance than other colour nets and hence had better performance in terms of plant height, number of leaves, biomass, leaf area, photosynthetic rate, harvest index compared to control. Vase life of the foliage was higher under coloured shade nets when compared to open condition but significance difference was not found between different colours. White and red shade nets were found to be best for growing cordyline.

An efficient protocol for in vitro multiplication of Rosa × hybrida L. cv. Happiness was standardized using axillary bud segments. Out of different pre treatments for explants, the highest explant survival (80.25%) was obtained with T1 pre-treatment comprising 0.2% Carbendazim + 0.2% Mancozeb-45 +150 mg/l 8-HQC for 4 hragitation on a horizontal shaker (200 rpm). Sucrose concentration of 30g/l in the medium was found to be optimum for in vitro shoot multiplication. Murashige and Skoog (MS) medium supplemented with 2.5 mg/l BAP + 5.0 mg/l kinetin + 0.1 mg/l NAA + 0.5 mg/l GA3 was found most effective for culture establishment, however, MS medium comprising 2.5 mg/l BAP + 2.5 mg/l kinetin + 0.1mg/l NAA+ 0.5mg/l GA3 along with 40 mg/l adenine sulphate was found to be better for shoot proliferation with highest number of micro shoots (7.10 shoots/explant). Rooting of micro shoots was induced on half strength MS basal medium supplemented with NAA (0.5 mg/l) and IBA (0.5 mg/l) rooting growth regulators. The regenerated plantlets were efficiently hardened in glass jars filled with coco peat + vermiculite + perlite (2:1:1) moistened with half strength MS medium salts and covered with polypropylene lids, thereafter, plants were successfully transferred to the glasshouse with good survival.

An investigation was carried out during 2013-14 to study the effect of different shade levels on the production and quality of cordyline (Cordyline terminalis Kunth.) under the subtropical condition of New Delhi, India. The effect of spectral control of light on physiology and vegetative development was evaluated at different crop growth stages. Shade nets did not only protect plants from high light intensities but also improved the vegetative growth, yield, vase life and quality of cordyline cut greens irrespective of shade level. Different shade levels modified microclimates, PAR, transmittance and canopy temperature. The shading improved plant characters like height, number of leaves, chlorophyll content, leaf area, fresh weight, harvest index and vase life. The plants grown under different shade levels showed improved photosynthetic activity and reduced transpiration rate. Plants grown under 50% shade level were taller, along with more number of leaves having longer petiole, chlorophyll content which can be attributed to higher photosynthetic rate, whereas harvest index and vase life was optimum. Overall, shade net with 50% shading was found best for commercial production of cordyline cut greens.

Twenty-one genotypes of African marigold were (Tagetes erecta L.) evaluated for 11 growth and flowering related traits to study their genetic parameters such as variability, heritability, genetic (GCV), phenotypic (PCV) coefficient of variation and correlation and path coefficient analysis. Analysis of variance for all the traits showed significant differences among genotypes for all the growth and flowering related traits. High range in mean performance has been observed for traits, viz. plant height (64.00-106.67 cm), plant spread (49.33-72.00 cm), flower diameter (3.77- 6.17 cm), days required for flowering (78.67-99.33 days), number of secondary branches (22.13-37.47) and flower duration (26.00-44.83 days). Higher genotypic and phenotypic coefficient of variation was observed for traits such as fresh flower weight per plant, flower fresh weight per 10 flowers, number of flowers per plant, stem girth, flowering duration, etc. The high value (> 90%) of heritability was observed for all traits except plant height, plant spread and stem girth. The genetic advance was found ranged from 1.23 for flower diameter to 288.69 for fresh flower weight per plant. High values of genetic advance as per cent of mean was recorded for number of flowers (59.79%) followed by fresh flower weight per plant (59.32%) and flower fresh weight per 10 flowers (58.09%). Fresh flower weight per plant is significantly and positively correlated both at genotypic and phenotypic level for plant spread, flower fresh weight per flower, number of flowers per plant and flower diameter. Path coefficient analysis at genotypic level revealed that the number of primary branches per plant contributed highest and has significantly positive direct effect on fresh flower weight per plant followed by number of flowers per plant, flower diameter, flower fresh weight per flower, days required for flowering and stem girth. The different genotypes were identified to be performing differently for different quantitative traits. Hence, those genotypes with superior traits could be involved in the hybridization programme for assembling of desirable traits in a single genotype.