Effect of Storage Conditions on Seed Viability of China Aster [Callistephus chinensis (L.) Nees]

The study revealed that China aster seeds lose viability quickly if stored under ambient conditions. At the end of 12th months, seeds stored at refrigerated condition (5-70C) still maintained high seed germination (64.00%) at field condition well above the minimum seed certification standards. However, in case of ambient storage very drastic reduction in seed germination was observed. It was 32.43 % for first months and reduced to 14.95 % for second month by declining 53.90% as compared to first month and thereafter no germination was recorded at field condition. Results from the interaction effect indicated that previously stored seeds of China aster for six months in aluminium foil and kept under refrigerated condition recorded higher seed quality parameters viz. percent seed germination at field (92.67 and 72.00%), percent survival of seedlings (89.33 and 70.67%), height of seedling (11.53 and 8.60 cm), shoot length (7.00 and 5.10 cm), root length (4.53 and 3.50 cm), shoot weight (0.42 and 0.33 g), root weight (0.040 and 0.027 g), root:shoot ratio (0.095 and 0.082) and percent seed germination at laboratory (97.33 and 76.00%) for first and sixth month, respectively.

RESPONSE OF CHINA ASTER (CALLISTEPHUS CHINENSIS L.) GENOTYPES TOWARDS FOLIAR APPLICATION OF GA3

China Aster is one of the most popular flower that are used in ornamental garden. The demand for cut flowers of China aster is increasing day by day, but it has not been possible to supply the adequate amount of flowers especially during the festival season. The area under flower production is increasing year after year but farmers are not getting quality seeds in adequate quantity as very few farmers are taking up seed production because flower seeds loose their viability earlier than crop seeds. So, production of adequate quantity of quality seeds is essential to meet the demand. The present investigation was undertaken in Horticulture Research Station, Mondouri, B.C.K.V., Mohanpur, Nadia, West Bengal during Rabi season of 2018-19 and 2019-20. Over two consecutive years, six genotypes were evaluated the potentiality of for its growth and flowering, as well as to estimate the influence of GA3 through foliar application at pre-flowering stage on its seed production. In field three treatments were considered viz. T1 (control i.e.no application of GA3), T2 (GA3@50ppm), T3 (GA3@100ppm). According to the size of flowers, highest was recorded in Local Mix (G6). So, it could be considered as the best performer genotype considering flower diameter. Seed yield plant-1 was recorded highest in Local White (G5), it could be considered as the best performer genotype considering its higher number of flowers plant-1 and number of seeds flower-1. GA3 (100 ppm) could be utilized in a better way for greater enhancement in all those important parameters as overall influence of GA3 has been found to improve seed yield plant-1 and all the important attributes. Concomitant consideration of seed yield and its important attributes may indicate to recommend foliar application of 100 ppm GA3 for enhancement in seed yield in all the genotypes. Similar to the seed yield and its attributes, plant growth and development have been noticed to be positively influenced by GA3 concentrations with a higher side after 100 ppm, may lead to recommend foliar application of 100 ppm GA3 for commercial cultivation of this crop irrespective of the genotypes.

Molecular characterization of China aster (Callistephus chinensis (L.) Nees) genotypes using SSR markers

Understanding genetic diversity in target populations is of great importance in breeding and a prerequisite for association mapping of traits. In this study, 57 cross species simple sequence repeat (SSR) markers were screened for amplification in China aster. Twenty six polymorphic markers were used to estimate the genetic diversity in forty two China aster genotypes. The observed and expected heterozygosities within the genotypes were ranged from 0.00 to 0.80 and 0.17 to 0.50, respectively. Weighted Neighbor Joining method, grouped China aster genotypes into five major clusters which coincided for morphological traits mostly flower color and form, but not correlated for their geographical locations. The results suggested that, population may be useful for the genome-wide marker–trait association mapping. These set of cross species transferable SSR markers would enable the application of the SSR technique in China aster crop improvement.

Influence of Microbial Consortium in the Production of China Aster and Gaillardia Seedlings

China aster and gaillardia are flowering plants with high economic importance in floriculture. In the present investigation, response of China aster and gaillardia seedlings to inoculation with the arbuscular mycorrhizal fungus Funneliformis mosseae + the plant growth-promoting rhizobacterium Bacillus sonorensis was studied by growing in multipots (pro trays). The germination percentage and plant growth parameters: length of shoots, roots and whole seedlings, stem diameter, biovolume index, plant strength, vigor index, dry weight and nutrient uptake, were analyzed 60 days after sowing. The microbial parameters, mycorrhizal root colonization and spore count, and the population of B. sonorensis in the substrate were also determined. The results brought out that growth of inoculated seedlings was significantly improved as compared to uninoculated seedlings. Based on the plant growth and microbial parameters studied, it was concluded that inoculating the substrate in pro trays with the microbial consortium results in producing vigorously growing seedlings.

Effects of organic manures and bio-fertilizers on growth, flowering and yield of China aster (Callistephus chinensis L. Nees var. Kamini)

Effects of organic manures and bio-fertilizers on growth, flowering and yield of China aster (Callistephus chinensis) var. kamini was investigated. The experiment with 12 treatment combinations comprising of FYM, vermicompost and bio-fertilizers viz., phosphate solublising bacteria (PSB) and Azospirillum was conducted. All the treatment combinations showed significant response in vegetative, flowering and yield characters during the entire investigation. The treatment combinations of Azospirillum + PSB + vermicompost + 50% RDF was found to be promising for maximum plant height (63.97 cm), plant spread (21.50 cm), stem girth (15.47 mm), number of primary branches per plants (12.33), number of secondary branches per plants (22.14), enhanced flower bud emergence (73.33 days), stalk length (32.20 cm), number of flowers per plant (24.35), flower diameter (46.18 mm), prolonged flower duration (23.05 days), flower yield (18.87 q/ha) and seed yield (2.44 q/ha) were on par with Azospirillum + PSB + FYM + 50% RDF.