American International Journal of Agricultural Studies Vol. 5, No. 1; 2021 ISSN 2641-4155 E-ISSN 2641-418X Published by American Center of Science and Education, USA 1 RESPONSE OF CHINA ASTER (CALLISTEPHUS CHINENSIS L.) GENOTYPES TOWARDS FOLIAR APPLICATION OF GA3 Sudipta Biswas PG Student Department of Seed Science and Technology Bidhan Chandra Krishi Viswavidyalaya Mohanpur - 741252, Nadia, West Bengal, India E-mail: sudiptabiswas.nxb96@gmail.com Dr. Sanjoy Kumar Bordolui (Corresponding Author) Assistant Professor Department of Seed Science and Technology Bidhan Chandra Krishi Viswavidyalaya Mohanpur - 741252, Nadia, West Bengal, India E-mail: sanjoy_bordolui@rediffmail.com Dr. Raghunath Sadhukhan Professor Department of Genetics and Plant Breeding Bidhan Chandra Krishi Viswavidyalaya Mohanpur - 741252, Nadia, West Bengal, India E-mail: drsadhukhan@gmail.com Received: August 08, 2021 Accepted: August 29, 2021 Online Published: September 07, 2021 DOI: 10.46545/aijas.v5i1.197 URL: https://doi.org/10.46545/aijas.v5i1.197 ABSTRACT 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 http://www.acseusa.org/journal/index.php/aijas mailto:sanjoy_bordolui@rediffmail.com https://www.acseusa.org/journal/index.php/aijas American International Journal of Agricultural Studies Vol. 5, No. 1; 2021 2 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. Keywords: China Aster, GA3, Seed Yield. INTRODUCTION Indian culture is a pleasing mingling of various subcultures. The culture shows a close connection with flowers from ancient era. However, the social and economic aspects of flower growing were recognized much later. The offering and exchange of flowers on all social occasions apart from use of flowers in worshipping and use of flowers in home decoration and hair adornment of women have made more opportunity for commercial cultivation of flowers. Among the various types of flowers, asters are one of the most beautiful and diverse flowers. The name of Aster comes from Greek word ‘aster’, which means star. According to Greek mythology, the goddess Asterea looked at the sky to watch the stars but she couldn’t see any stars. This incident made her sad and she started weeping, where her tears fell on the ground, asters began to grow there. In Victorian England, floriography i.e. coded communication through the exchange of flowers, was all the rage and asters, with their wide range of colors act as the perfect medium. Purple asters represented wisdom and royalty, and were most popular aster. White aster stood for purity, perfection, and innocence. Red asters stood for devotion whereas pink asters stood for love. These days floriography is not in fashion yet, but asters still have an active symbolic life. China Aster is a monotypic genus of flowering plants in the family Asteraceae which contains the single species. Cassini described China aster as Callistephus hortensis but Linnaeus named it as Aster chinensis. Then, Nees changed its name to Callistephus chinensis. The genus Callistephus is evolved from Greek word ‘Kalistos’ meaning ‘most beautiful’ and ‘Stephos’ which means ‘a crown’ referring to the flower head. Plants of china aster are erect, alternate bearing. It has broadly ovate or triangular ovate, irregularly toothed leaves. Flowers are solitary, contains two types of florets: ray florets and disc florets. The discs are ray florets are long and short. They have daisy like or star like flower heads with a yellow center. The most suitable character for the classification of China aster is by the shape of ray florets (Janakiram & Rao, 2002).The wide spectrum of colour ranges available in China aster are pink, bluish violet, purple and white. Their attractive colour and long shelf life have made them a popular cut flower. Flower quality is primarily a varietal trait. It is influenced by climatic conditions of growing period. Optimum temperature and requisite photoperiod helps in obtaining better blooms of good size and high quality (Nagaraju et al., 2004).The advantages of growing aster are short duration, suitable as intercrop in coconut and it has good seed setting. It is normally winter season flowering annual which is adapted to wide range of agroclimatic regions. The flower colour is well developed in the temperature range of 20-300C during day and 15-170C https://www.acseusa.org/journal/index.php/aijas American International Journal of Agricultural Studies Vol. 5, No. 1; 2021 3 during night with relative humidity of 50- 60% and 500-700mm rainfall. Flowers of china asters are used for various purposes like flower decoration, preparation of bouquets, garlands, landscape gardening for aesthetic purpose. It is commercially cultivated in various countries like India, France, Germany, Netherlands, U.K., Siberia, Russia, Japan, North America, Switzerland and England (Raghava, 1984). In India, China aster is largely grown on commercial scale in southern states mainly in Karnataka, Tamil Nadu, Andhra Pradesh, Maharashtra and also some eastern state like West Bengal. In Karnataka, the cultivated area is over an area of 775 lakh ha with an annual production of 6206 tonnes of flowers (Anonymous, 2000). Increased flower production, quality of flowers and perfection in the form of plants are important objectives to be followed in commercial flower production. So, it is essential to meet the demand of adequate quantity of quality seeds for flower as well as seed production. Application of GA3 is an effective plant growth hormone which stimulates the cells elongation. GA3 is a lead to produce high seed production. It has ability to regulate plant height, enhance branches, increase productive (Gavino et al., 2008; Yuan et al., 2003). With the above view, present investigation has been carried out to evaluate China aster flower crop by applying GA3 treatment and record its various seed quality parameters during 2018-2019 and 2019-2020 at Horticulture Research Station, Mondouri, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia, West Bengal, India with the main objective of assessment of the effect of GA3 on growth, development flowering and seed production of different genotypes of China Aster. MATERIALS AND METHODS The field experiment was conducted in new alluvial zone at Horticulture Research station, Mondouri, Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia, West Bengal, India during rabi season of 2018-19 and 2019-20. Soil pH of experimental site was 6.6-6.7, containing organic carbon 0.74%, sandy loam in texture, total available Nitrogen 0.07%, Phosphorus 28.50 kg ha-1 and potassium 78 kg ha-1. Seeds of six China aster genotypes viz. Arka Kamini (G1), Arka Archana (G2), Arka Adya (G3), Local pink (G4), Local White (G5) and Local Mix (G6) were sown in the experimental plots. Standard agronomic practices and intercultural operations were followed for raising seedlings in individual plots. Forty days old healthy and uniformly grown seedlings were used for transplanting with a spacing of 40 cm x 40 cm with three replications following Randomised Block Design. A spacing of 45cm between two replications and 45cm between two plots was given to design of water system channels and bunds, individually. The whole exploratory land was separated into plots estimating 2.5 m x 2.5 m. with 54 plots altogether. Farm yard manure was applied @ 2kg plot-1. Fertilizer dose of 10:26:26 (N:P: K mixed fertilizer) @ 150g plot-1 was applied as basal portion and another 50g plot-1 at 20 days after transplanting. Foliar application of both the doses of Gibberellic acid (i.e. 50 ppm and 100 ppm) was made on plants at three weeks after transplanting and the non-sprayed plants were treated as control. Five plants were randomly tagged at the early crop growth stage and observations on different traits were recorded by a specific method, like plant height (cm), days to bud initiation, days 50% flowering, flower diameter (cm), head diameter (cm), number of flower plant-1, number of seed flower-1, test weight (g) and seed yield plant-1 (g). RESULTS AND DISCUSSION Different agronomic characters excepting test weight for which it was made during 2018-19 and 2019-20 along with the quality parameters (physiological) of the produced seeds by considerations of effect of GA3 as foliar application was made over two consecutive years. https://www.acseusa.org/journal/index.php/aijas American International Journal of Agricultural Studies Vol. 5, No. 1; 2021 4 Significant variation among the performance of the genotypes, influence of doses of GA3 as well as its interaction effects observed for all agronomic characters. Gibberellic acid (GA) is a tetracyclic di-terpenoid compound. It is a plant hormone stimulating plant growth and development. It influences seed germination, trigger transitions from meristem to shoot growth, vegetative to flowering and seed development along with an interaction of different environmental factors viz., water, light and temperature. GA3 is sometime act as paracrine signals; it is still a mystery to understand the GA3 biosynthesis and its movement. It has not yet established the significant site of bioactive GA3 in plants or which tissues earmarked by bioactive GA3 to commence their action. Plant Height (cm) Significantly tallest plants were observed for G4 (Local pink) followed by G6 (Local Mix), when average was made over the treatments, while most dwarf plants were recognized for G5 (Local White) (50.277cm) preceded by G1 (Arka Kamini) and G2 (Arka Archana), significant difference could be noticed among genotypes during 2018-19 (Table 1). Average influence of 100 ppm GA3 was significantly superior to that of 50 ppm GA3 over control for exhibition of plant height at 50% flowering stage. While considering the interaction between genotypes and treatments, significantly maximum plant height was recorded for G4 after application of 100 ppm GA3 followed by same genotype after application with 50 ppm of GA3. Similar to the average influence of GA3 doses, high GA3 dose exerted greater influence than that of lower dose for almost all the genotypes for which significant difference between influences of both the doses of GA3 was recognized. Average plant height at 50% flowering of G4 (i.e., Local pink) was also found to be maximum (69.452 cm) followed by that of G6 (i.e., Local Mix) when average was made over the treatments during 2018-19 as was observed in second year; same like first year, G5 (Local White) produced dwarf plants of average 50.154cm height preceded by those of G1, significant difference could be noticed in 2018-19. Significantly enhanced average plant height over control (without application of GA3) could also be recorded after application of GA3 and plant height increased with the increased concentration of GA3 (Table 1). The trend in enhancement in plant height of individual genotypes also followed the similar pattern as was recorded for average influence of GA3 concentration and significant difference between influence of 50 and 100 ppm GA3 could be noticed. Plant height was recorded to be as maximum as 75.963cm for G4 after application of 100 ppm GA3 followed by that of same genotype after application of 50 ppm of GA3. Similar type of result in plant height on marigold was also documented previously by (Rai & Bordolui, 2020). Table 1. Variation in plant height (cm) of different China Aster genotypes G1 G2 G3 G4 G5 G6 Mean T 2018-2019 T1 49.630 50.293 55.663 63.510 44.307 59.220 53.771 T2 53.530 55.923 59.743 69.437 50.080 64.147 58.810 T3 58.327 59.563 65.850 76.017 56.443 68.113 64.052 Mean G 53.829 55.260 60.419 69.654 50.277 63.827 T G T X G SEm(±) 0.269 0.381 0.659 https://www.acseusa.org/journal/index.php/aijas American International Journal of Agricultural Studies Vol. 5, No. 1; 2021 5 LSD (0.05) 0.777 1.099 1.924 2019-2020 T1 49.200 50.250 55.577 63.250 44.233 58.890 53.567 T2 53.407 55.850 59.627 69.143 49.830 64.020 58.646 T3 57.997 59.510 65.610 75.963 56.400 67.860 63.890 Mean G 53.534 55.203 60.271 69.452 50.154 63.590 T G T X G SEm(±) 0.264 0.373 0.647 LSD (0.05) 0.762 1.078 1.867 Note: T = Treatment, T1 = Control, T2 = 50 ppm GA3, T3 = 100 ppm GA3, G = Genotypes, G1 = Arka Kamini, G2 =Arka Archana, G3 = Arka Adya, G4 = Local pink, G5 =Local White, G6 = Local Mix Days to Flower Bud Initiation Among the genotypes over treatments, longest duration to flower bud initiation was noted for G1 i.e. Arka Kamini (88.511days) during the year 2018-19 followed by G2 i.e. Arka Archana (81.487days), while it was minimum for G5i.e. local white(71.756 days) preceded by G4Local pink (72.433days).Among the treatments over the genotypes, maximum duration to bud initiation was observed for T1 (80.607 days) i.e., in control condition and it was minimum for T3 (75.071days) i.e., 100 ppm GA3.It has been observed that days required for bud initiation was reduced with the application of GA3.The interaction between GA3 treatment and genotype is noted overall significant though the influence of GA3 concentration on individual genotypes was varied non significantly in genotype G4 for both the doses of GA3 treatments and where no significant difference in days to flower bud initiation was observed. Non-significant difference was observed between the genotype G3 and G6 for the treatment T2 and for the treatment T3 i.e. 100ppm GA3 dose; also in case of genotype G4 and G5 non-significant difference was observed in days to flower bud initiation in control as well as in T2.However, maximum days (80.607days) taken to bud initiation was recorded in the control plot i.e. without application of GA3. The average performance of the genotypes and influence of GA3 concentration in 2019- 20 was almost similar to that observed in 2018-19, except minimum time taken for flower bud initiation was observed in G4 i.e. Local pink (70.557days) preceded by G5i.e Local white, (71.567days),which may be due to the variation in climatic conditions during experimentation over the years (Table 2).When considering interaction between treatments and genotypes, overall it was significant. But it was varied non-significantly among the genotypes G5 and G6 for both doses of GA3, between G4, G5 for both the treatments and for control and G5, G6 for control. In the year 2019-20; still maximum number of days (90.357days) taken to bud in initiation was recorded for without GA3 application and consistent reduction in days to flower bud initiation was noticed for all the genotypes with enhancement in GA3 concentration. Similar type of result in days to flower to bud initiation was also documented previously by (Mahato et al., 2017). Table 2. Variation in days to flower bud initiation (cm) of different China Aster genotypes G1 G2 G3 G4 G5 G6 Mean T 2018-2019 T1 90.357 85.343 81.150 74.377 75.197 77.217 80.607 T2 88.820 81.073 75.723 71.923 72.143 75.373 77.509 https://www.acseusa.org/journal/index.php/aijas American International Journal of Agricultural Studies Vol. 5, No. 1; 2021 6 T3 86.357 78.043 73.433 71.000 67.927 73.667 75.071 Mean G 88.511 81.487 76.769 72.433 71.756 75.419 T G T X G SEm(±) 0.251 0.355 0.615 LSD (0.05) 0.725 1.025 1.775 2019-2020 T1 90.433 84.400 81.057 74.597 75.200 76.467 80.359 T2 88.980 81.203 76.960 70.930 71.963 75.707 77.624 T3 86.690 78.110 74.043 66.143 67.537 74.000 74.421 Mean G 88.701 81.238 77.353 70.557 71.567 75.391 T G T X G SEm(±) 0.234 0.330 0.572 LSD (0.05) 0.674 0.953 1.651 Note: T = Treatment, T1 = Control, T2 = 50 ppm GA3, T3 = 100 ppm GA3, G = Genotypes, G1 = Arka Kamini, G2 =Arka Archana, G3 = Arka Adya, G4 = Local pink, G5 =Local White, G6 = Local Mix Days to 50% flowering Significant difference was observed among the genotypes over treatments both the years; highest days to 50% flowering was recorded in G1 i.e. Arka Kamini (108.778days for first year and 108.520days for second year), followed by genotype G2 i.e. Arka Archana (96.808daysfor first year and 96.922 days for second year) and lowest days to 50% flowering was recorded in genotype G4i.e Local Pink (87.254daysfor first year and 87.150 days for second year) preceded by G5, G6 and G3. Among the treatment over genotypes significant difference was observed. Maximum duration of 50% flowering was recorded in T0 (97.615 days) and it was consistently reduced with the enhancement in GA3 concentration in both the years. In case of interaction between genotypes and foliar application of GA3 non-significant difference was recorded. Though change in magnitudes for this parameter of individual genotypes after foliar application of GA3was recorded non-significant in both years, G1 took the maximum number of days to 50% flowering without application of GA3 irrespective of the years of experimentation followed by that of G2, G3 and G6. Similar type of result in days to 50% flowering on rice was also documented previously by (Biswas et al., 2020). Table 3. Variation in days to 50% flowering of different China Aster genotypes after GA3 application G1 G2 G3 G4 G5 G6 Mean T 2018-2019 T1 112.187 100.067 97.267 90.173 91.967 94.030 97.615 T2 107.947 96.323 93.187 87.323 89.037 91.483 94.217 T3 106.200 94.033 91.133 84.267 86.933 89.000 91.928 Mean G 108.778 96.808 93.862 87.254 89.312 91.504 T G T X G SEm(±) 0.175 0.247 0.428 LSD (0.05) 0.505 0.714 NS 2019-2020 https://www.acseusa.org/journal/index.php/aijas American International Journal of Agricultural Studies Vol. 5, No. 1; 2021 7 T1 112.023 100.550 97.373 90.117 92.090 94.037 97.698 T2 107.337 96.200 93.150 87.240 89.063 91.493 94.081 T3 106.200 94.017 91.267 84.093 86.807 89.300 91.947 Mean G 108.520 96.922 93.930 87.150 89.320 91.610 T G T X G SEm(±) 0.160 0.226 0.391 LSD (0.05) 0.461 0.652 NS Note: T = Treatment, T1 = Control, T2 = 50 ppm GA3, T3 = 100 ppm GA3, G = Genotypes, G1 = Arka Kamini, G2 =Arka Archana, G3 = Arka Adya, G4 = Local pink, G5 =Local White, G6 = Local Mix Flower Diameter (cm) Flower diameter is enhanced with increased dose of foliar application of GA3 over control. Average potentiality of individual genotypes with respect to flower diameter of genotypes over treatments was significantly varied among it selves. During first year (2018-2019), genotype G6 i.e. local mix secured largest average flower diameter (6.552cm) followed by genotype G4 i.e. Local pink (6.456cm) and G5 i.e. Local white (6.201cm) respectively. Beside this, smallest average flower diameter was recorded in the genotype G1 i.e. Arka Kamini (5.459cm) proceeded by G2 i.e. Arka Archana and G3 i.e. Arka Adya respectively (Table 4).Among the treatment over genotypes significant difference was observed when considered as average. Largest flower diameter (6.354cm) was recorded under T3 i.e. 100ppm GA3 treatment and it is reduced towards lower dose application and in control respectively. In case of interaction, change in magnitudes for this parameter of individual genotypes after foliar application of GA3was recorded significant; maximum flower diameter was noted in genotype G6 i.e. Local mix (6.823cm). The interaction between treatments and genotypes significantly varied in first year. Highest value was recorded in T3G6 and lowest in T3G6. The average performance of the genotypes and influence of GA3 concentration in 2019- 20 was almost similar to that observed in 2018-19 with slight change in magnitude which may be due to the variation in climatic conditions during experimentation over the years (Table 4). The interaction between treatments and genotypes, was varied significantly overall though non- significant difference is recorded between the genotype G4 and G6 in control for the considered parameter. Largest flower diameter was recorded in genotype G6 (6.867cm) and smallest flower diameter was recorded in the genotype G1 (5.492cm) as like in first year. Table 4. Variation in flower diameter of different China Aster genotypes after GA3 application G1 G2 G3 G4 G5 G6 Mean T 2018-2019 T1 5.237 5.360 5.603 6.187 5.770 6.257 5.736 T2 5.463 5.823 5.970 6.473 6.323 6.577 6.105 T3 5.677 6.053 6.353 6.707 6.510 6.823 6.354 Mean G 5.459 5.746 5.976 6.456 6.201 6.552 T G T X G https://www.acseusa.org/journal/index.php/aijas American International Journal of Agricultural Studies Vol. 5, No. 1; 2021 8 SEm(±) 0.009 0.013 0.023 LSD (0.05) 0.027 0.039 0.067 2019-2020 T1 5.247 5.373 5.617 6.213 5.823 6.277 5.758 T2 5.480 5.857 6.027 6.490 6.407 6.603 6.144 T3 5.750 6.103 6.410 6.787 6.600 6.867 6.419 Mean G 5.492 5.778 6.018 6.497 6.277 6.582 T G T X G SEm(±) 0.009 0.013 0.022 LSD (0.05) 0.026 0.037 0.065 Note: T = Treatment, T1 = Control, T2 = 50 ppm GA3, T3 = 100 ppm GA3, G = Genotypes, G1 = Arka Kamini, G2 =Arka Archana, G3 = Arka Adya, G4 = Local pink, G5 =Local White, G6 = Local Mix Head Diameter (cm) Head size was consistently increased among the various genotypes with increasing the dose of foliar application of GA3compared to control. Overall significant difference was observed when considering average performance of genotypes over treatments as well as in case of treatment over genotypes. Though non-significant differences was observed among the genotypes G1 and G2, G2 and G3, G3 and G4, G4 and G5 when considering average performance of the mentioned genotype over the treatments during the year 2018-2019. Highest average head diameter was noted in case of genotype G5 i.e. local white (2.001cm) followed by genotype G6 i.e. Local Mix (1.964cm), G4 i.e. Local pink (1.906cm) respectively. Smallest head diameter is recorded in the genotype G3 i.e. Arka Adya (1.808cm) preceded by G2 and G1 (Table 5).When considering treatments over genotypes, the parameter varied significantly. Highest magnitude in head diameter was noted for T3 i.e. 100ppm foliar application of GA3 and lowest is observed in case of control. Overall significant difference is observed in case of interaction between genotypes and treatments; though non-significant difference is observed between genotype G1, G2, G3, G4, G5 and G6 when critically observing the interaction (Table 5). Highest head diameter was recorded for genotype G1 i.e. Arka Kamini (2.227cm) when foliar application of 100ppm GA3 was given. The average performance of the genotypes and influence of GA3 concentration in 2019- 20 was almost similar to that observed in 2018-19.The trend in performance of individual genotypes for head diameter in second year was also similar to that recorded in first year, especially with regard to highest and lowest head size. Interaction between treatments and genotypes, was varied significantly overall though non-significant difference is recorded among the genotype G1, G2, G3 and among G4, G5, G6 over various treatment. https://www.acseusa.org/journal/index.php/aijas American International Journal of Agricultural Studies Vol. 5, No. 1; 2021 9 Table 5. Variation in head diameter of different China Aster genotypes after GA3 application G1 G2 G3 G4 G5 G6 Mean T 2018-2019 T1 1.620 1.520 1.600 1.760 1.873 1.820 1.698 T2 1.770 1.930 1.833 1.793 2.010 2.007 1.891 T3 2.227 2.053 1.990 2.163 2.120 2.067 2.103 Mean G 1.872 1.834 1.808 1.906 2.001 1.964 T G T X G SEm(±) 0.030 0.043 0.074 LSD (0.05) 0.087 0.123 0.213 2019-2020 T1 1.640 1.550 1.613 1.807 1.887 1.843 1.753 T2 1.797 1.920 1.853 1.823 2.050 2.103 1.924 T3 2.257 2.080 2.017 2.177 2.153 2.107 2.132 Mean G 1.898 1.850 1.828 1.936 2.030 2.018 T G T X G SEm(±) 0.027 0.038 0.065 LSD (0.05) 0.077 0.108 0.188 Note: T = Treatment, T1 = Control, T2 = 50 ppm GA3, T3 = 100 ppm GA3, G = Genotypes, G1 = Arka Kamini, G2 =Arka Archana, G3 = Arka Adya, G4 = Local pink, G5 =Local White, G6 = Local Mix Number of Flower Plant-1 Overall significant difference was observed when average was made among the genotypes over treatments for both the years; in the year 2018-2019 highest average number of flower per plant was recorded in G5 i.e. Local White (36.800) followed by genotype G2and G1(Table 6)and lowest average number of flower was recorded in genotype G6i.e Local Mix (24.456 ) preceded by G3 and G1 (Table 6). Among the treatment over genotypes significant difference was observed. Maximum number of flowers was recorded in T3 (36.844) and it was consistently reduced with the lower GA3 concentration in both the years. In case of interaction, significant difference was observed overall but when observing critically, non- significant difference is observed between the performance of the genotype G3 and G4, G1 and G2 over control and in case of genotype G3 and G6, G1 and G2, G4 and G1 over T2 and in between the genotype G1 and G2 over T3. Maximum number of flowers was recorded in T3 (36.844) and it was consistently reduced with the decrease in GA3 concentration in both the years Similar pattern of improvement in flower number was recognized after utilization of GA3 in second year as like as first year. The performance of individual genotypes for number of flowers per plant in second year was as likewise as that recorded in first year, especially with respect to maximum and minimum number of flower (Table 6). Interaction of genotypes with the treatment was noted overall significant. Though insignificant difference was noticed between the genotype G3 and G4 under unsprayed plot, in addition to this non-significant difference was observed among the genotypes G1, G2, G4 and between G3 and G6 for application of 50ppm GA3 when observing critically (Table 6). https://www.acseusa.org/journal/index.php/aijas American International Journal of Agricultural Studies Vol. 5, No. 1; 2021 10 Table 6. Variation in number flower plat-1 of different China Aster genotypes after GA3 application G1 G2 G3 G4 G5 G6 Mean T 2018-2019 T1 22.533 24.467 20.400 20.533 28.433 17.767 22.356 T2 29.933 30.633 24.500 28.767 34.833 25.633 29.050 T3 37.700 38.467 32.867 34.933 47.133 29.967 36.844 Mean G 30.056 31.189 25.922 28.078 36.800 24.456 T G T X G SEm(±) 0.375 0.530 0.918 LSD (0.05) 1.082 1.531 2.651 2019-2020 T1 22.500 25.233 20.033 20.667 28.833 16.867 22.356 T2 29.733 30.433 23.967 29.733 34.633 25.367 28.978 T3 37.533 38.500 33.367 35.533 46.300 29.800 36.839 Mean G 29.922 31.389 25.789 28.644 36.589 24.011 T G T X G SEm(±) 0.380 0.537 0.930 LSD (0.05) 1.096 1.550 2.686 Note: T = Treatment, T1 = Control, T2 = 50 ppm GA3, T3 = 100 ppm GA3, G = Genotypes, G1 = Arka Kamini, G2 =Arka Archana, G3 = Arka Adya, G4 = Local pink, G5 =Local White, G6 = Local Mix Number of Seed Flower-1 Significant difference was observed among the average performance of genotypes over treatments for this trait. Highest number of seeds flower-1 was recorded for the genotypeG4 (210.751) followed by G5 while smallest number of seeds flower-1 was recorded for G3 (100.640) followed by G1 when considering average (Table 7). There was a rise in number of seeds flower-1 with enhanced dose of GA3 compared to unsprayed condition. When considering treatments over genotypes, the parameter varied significantly. Highest number of seeds flower-1 was recorded for T3 (182.318), and it reduced with decreased dose of GA3 (Table 7).Significant difference was observed in interaction between treatments and genotypes. Highest number of seeds flower-1 was recorded for the genotype G4 (218.513) when treated with100ppm GA3 while lowest number of seed per flower head was recorded for the genotype G3 (93.460) in control. It is markable that, potential of producing seeds flower-1 was varied genotype to genotype which may conclude that this parameter is genotype specific. Average performance of genotypes in response to various treatments varied significantly in final year. Highest and lowest number of seeds flower-1 was recorded for the same genotypes https://www.acseusa.org/journal/index.php/aijas American International Journal of Agricultural Studies Vol. 5, No. 1; 2021 11 as was in first year. Similar pattern of improvement in flower number was recognized after utilization of GA3 in second year as like as first year. The performance of individual genotypes for number seeds flower-1 in second year was as likewise as that recorded in first year with a minor change in magnitude. Significant variation was observed when considering interaction between genotypes and treatments. Highest number of seeds flower-1 was recorded in genotype G4 and lowest in case of genotype G3as likewise in first year with a slight change in magnitude (Table 7). Table 7. Variation in number of seed flower-1 of different China Aster genotypes after GA3 application G1 G2 G3 G4 G5 G6 Mean T 2018-2019 T1 161.133 175.593 93.460 203.293 193.867 171.270 166.436 T2 168.140 181.783 100.430 210.447 199.523 180.547 173.478 T3 177.010 190.293 108.030 218.513 209.393 190.667 182.318 Mean G 168.761 182.557 100.640 210.751 200.928 180.828 T G T X G SEm(±) 0.326 0.461 0.798 LSD (0.05) 0.941 1.331 2.073 2019-2020 T1 161.300 175.377 93.370 203.223 193.887 171.330 166.415 T2 168.483 182.243 100.223 210.113 199.857 181.470 173.732 T3 176.993 190.477 107.533 218.060 209.143 191.013 182.203 Mean G 168.926 182.699 100.376 210.466 200.962 181.271 T G T X G SEm(±) 0.291 0.412 0.714 LSD (0.05) 0.841 1.189 2.060 Note: T = Treatment, T1 = Control, T2 = 50 ppm GA3, T3 = 100 ppm GA3, G = Genotypes, G1 = Arka Kamini, G2 =Arka Archana, G3 = Arka Adya, G4 = Local pink, G5 =Local White, G6 = Local Mix Test Weight (g) Unlike other parameters, test weight of seeds of different genotypes was recorded for final year only. Significant difference was observed overall when average was made among the genotypes over treatment. Though non-significant difference was observed between average test weight in between G4 and G5; highest average test weight was recorded in G1(1.922) followed by G6 and G3 while lowest average test weight was noticed in G2 preceded by G5 and G4.Impact of foliar application of GA3 on various genotypes recorded significant when considering average where highest test weight was recorded for T3 (1.944).When considering interaction of treatments with genotypes, overall significant difference was observed. But when observing critically, some genotypes like G3, G4 in T1 and G5; G1 and G6 in T1 again G4, G5 and G6 in T2; G1, G5 and G6 in T2 showed insignificant difference in their test weight. https://www.acseusa.org/journal/index.php/aijas American International Journal of Agricultural Studies Vol. 5, No. 1; 2021 12 Table 8. Variation in test weight of seed different China Aster genotypes after GA3 application G1 G2 G3 G4 G5 G6 Mean T T1 1.813 1.673 1.740 1.737 1.720 1.793 1.746 T2 1.920 1.750 1.840 1.817 1.803 1.903 1.839 T3 2.033 1.860 1.930 1.900 1.920 2.020 1.944 Mean G 1.922 1.761 1.837 1.818 1.814 1.906 T G T X G SEm(±) 0.003 0.005 0.008 LSD (0.05) 0.010 0.014 0.024 Note: T = Treatment, T1 = Control, T2 = 50 ppm GA3, T3 = 100 ppm GA3, G = Genotypes, G1 = Arka Kamini, G2 =Arka Archana, G3 = Arka Adya, G4 = Local pink, G5 =Local White, G6 = Local Mix Seed Yield Plant-1 (g) Significant difference was observed among the average performance of genotypes over treatments in 1styears. Highest average seed yield plant-1 was recorded for the genotype G5 (3.577g) followed by G4 (3.183g). Lowest yield plant-1was recorded in G3 for both the years. When considering treatments over genotypes significant variation was noticed with highest magnitude of seed yield plant-1in T3 for both the years; concluding that application of GA3 has a positive impact on seed yield. In case of interaction effect, overall significant variation was observed. Highest seed yield plant-1was recorded in G5 (3.980 g) when treated with 100ppm GA3. On the other hand, lowest seed yield plant-1was recorded in G3 (1.860g) in control. Average performance of genotypes in response to foliar application of GA3 varied significantly in final year. Highest and lowest seed yield plant-1was recorded for the same genotypes as noted in first year. Similar pattern of improvement in seed yield was recognized after utilization of GA3 in second year just like first year. The performance of individual genotypes for seed yield plant-1 in second year was as likewise as that recorded in first year with a minor change in magnitude. Significant variation was observed when considering interaction between genotypes and treatments; with highest yield of 3.987g in G3 when treated by T3. Similar type of result in seed yield plant-1 was also documented previously by (Chakraborty et al., 2019). Table 9. Variation in seed yield plant-1 (g) of different China Aster genotypes after GA3 application G1 G2 G3 G4 G5 G6 Mean T 2018-2019 T1 2.340 2.280 1.860 2.500 2.923 2.007 2.318 T2 3.337 3.150 2.777 3.463 3.827 3.053 3.268 T3 3.460 3.353 3.057 3.587 3.980 3.247 3.447 Mean G 3.044 2.928 2.564 3.183 3.577 2.769 T G T X G SEm(±) 0.008 0.011 0.018 https://www.acseusa.org/journal/index.php/aijas American International Journal of Agricultural Studies Vol. 5, No. 1; 2021 13 LSD (0.05) 0.022 0.031 0.053 2019-2020 T1 2.361 2.290 1.897 2.513 2.947 2.053 2.343 T2 3.347 3.153 2.770 3.490 3.860 3.063 3.281 T3 3.520 3.420 3.060 3.610 3.987 3.347 3.491 Mean G 3.076 2.954 2.576 3.204 3.598 2.821 T G T X G SEm(±) 0.007 0.009 0.016 LSD (0.05) 0.019 0.027 0.047 Note: T = Treatment, T1 = Control, T2 = 50 ppm GA3, T3 = 100 ppm GA3, G = Genotypes, G1 = Arka Kamini, G2 =Arka Archana, G3 = Arka Adya, G4 = Local pink, G5 =Local White, G6 = Local Mix i)Arka Kamini(V1) ii)Arka Archana(V2) iii)Arka Aadya(V3) iv)Local Pink(V4) https://www.acseusa.org/journal/index.php/aijas American International Journal of Agricultural Studies Vol. 5, No. 1; 2021 14 v)Local White(V5) vi)Local Mix(V6) Figure 1. Field performance of different genotypes of China aster CONCLUSIONS Among the genotypes, highest flower size was recorded in Local Mix (G6). So, it could be recommended 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 enhance seed yield plant-1 and all the important attributes. Seed yield is an important attributes may indicate to recommend foliar application of 100 ppm GA3 for enhancement this trait for all the genotypes. The plant growth and development have been noticed to be positively influenced by GA3 @ 100 ppm, may lead to recommend foliar application of 100 ppm GA3 for commercial cultivation of this crop irrespective of the genotypes. REFERENCES Anonymous. (2000). Statistical Data on Horticultural crops in Karnataka state, Department of Horticulture, Lalbagh, Bangalore. Biswas, S., Bordolui, S.K., & Chattopadhyay, P. (2020). Influence of GA3 on hybrid rice seed production in West Bengal. Journal of Crop and Weed, 16(3), 136-142 Chakraborty, A., Bordolui, S.K., Mahato, M. K., Sadhukhan, R., & Sri Veda, D.J.M.S.N.K. (2019). Variation in seed production potential of China aster genotypes in the New Alluvial Zone of West Bengal. Journal of Crop and Weed, 15(1), 201-204. Gavino, R.B., Pi Y & Abon Jr, C.C. (2008). Application of gibberellic acid (GA3) in dosages for three hybrid rice seed production in the Philippines. J. Agril. 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Effect of GA3 on marigold seed production in Gangetic Alluvial Zone. Journal Crop and Weed, 16(1), 120-126. Yuan, L., Wu, X., Liao, F., Ma, G. and Xu, Q. (2003). Hybrid Rice Technology. China Agricultural Press, Beijing, China, pp. 132. Yuan, L.P. (1985). A Concise Course in Hybrid Rice. Changsha, China: Human Technology Press. Copyrights Copyright for this article is retained by the author(s), with first publication rights granted to the journal. This is an open-access article distributed under the terms and conditions of the Creative Commons Attribution license (http://creativecommons.org/licenses/by/4.0).