Ppm GA3 Research Articles

Effect of Different Seed Treatments and Media on Growth and Biomass of Indian Cheese Maker - Withania coagulans (Stocks) Dunal.

The present investigation was conducted to assess the effect of different seed soaking treatments and media on growth and alkaloid content of Indian cheese maker–Withania coagulans (Stocks) Dunal. to develop effective nursery production technology. The experiment was conducted in completely randomized design with factorial concept, including twenty treatment combinations comprising of four levels of seed treatments with GA3 (0, 50, 100, 150 ppm) and five levels of different growing media. Among various concentrations of GA3 as pre-soaking treatment, 100 ppm GA3 (S3) showed significantly better results for germination, growth, biomass and alkaloid content in W. coagulans. Similarly, among growing media, red soil (M1) recorded maximum germination percentage, collar diameter, number of branches per plant, number of leaves per plant, total leaf area, length of the main root, thickness of main root, root dry biomass, shoot dry biomass, fresh weight of plant, dry weight of plant, survival percentage of the plant and total alkaloid content of plant. Overall, the result indicated that that pre-sowing W. coagulans seeds with GA3 -150 ppm for 24 hrs and subsequently sowing treated seeds in M1 media comprising of red soil (control) can enhance growth and alkaloid content.

Effect of Gibberellic Acid and Germination Medium on Kiwifruit Seed Germination

In Bhutan, cultivation of exotic commercial Kiwifruit fruit is new though wild kiwifruit is found aplenty. There is a high scope for kiwifruit cultivation as it is suitable in a wide range of areas in the country. It can also be grown organically due to the lack of any known serious pest or disease. Fittingly, kiwifruit is counted among the most potential high-value fruit crops in the country. Its cultivation is gaining popularity in the current times and it would consequently increase the demand for kiwifruit seedlings. Kiwifruit seeds exhibit physiological seed dormancy which hampers kiwifruit seedling production. Hence, a study was conducted in 2019 and 2020 at ARDC, Wengkhar. In the study, the combined effect of GA3 and growth medium on kiwifruit seed germination was studied using eight treatments with three replications laid out in a Completely Randomized Design. The study aimed to find out the germination parameters like germination percentage, relativized percentage, mean germination time, time taken for 10% germination, and time taken for 25% germination. According to the study, Cocopeat + 1500 ppm GA3 gave the best germination percentage at 51% followed by Biochar + 1500 PPM at 39% while rice bran and compost exhibited a low germination percentage. Overall, the mean germination time was found to be 50 days. The highest relativized percentage of 63 % was observed in Cocopeat + 1500 ppm GA3. As for the time taken to achieve 10% and 20% germination, those treatments with 1500 GA3 application had an advantage of approximately eight days over the others. Overall, considering the average weighted effect of germination percentage and time, Cocopeat + GA3 1500 PPM gave the best result followed by Biochar + GA3 1500 PPM and Cocopeat + GA3 0 PPM. Hence, the study indicates that GA3 treatment in combination with an appropriate germination medium can significantly enhance seed germination in kiwifruit.

Efficacy of various doses of salicylic acid, naphthalene acetic acid and gibberellic acid on vegetative growth and pod yield of broad bean (Vicia faba L.)

To investigate the efficacy of various doses of plant growth regulators on vegetative growth and pod yield of broad bean (Vicia faba L.), a field experiment was accomplished at Vegetable Research Farm, B.H.U., Varanasi during the winter season of 2019-20. Ten treatments were evaluated in randomized block design with three replications. Results indicated that the growth parameters like plant height, number of branches/plant significantly increased with foliar spray of gibberellic acid followed by NAA and salicylic acid. The yield attributes like pod width, fresh pod weight, number of pods/plant as well as fresh pod yield significantly enhanced by NAA followed by gibberellic acid and salicylic acid with various concentrations, respectively. The foliar spraying of 120 ppm GA3 tended to produce plant with maximum height (116.4 cm), number of branches/plant (6.3), pod length (7.5 cm), number of seeds/pod (4.6) as well as early 50 % flowering (57.3 days) whereas, spraying of 40 ppm NAA exhibited the maximum pod width (1.3 cm), fresh pod weight (4.6 g), number of pods/plant (87.5) as well as fresh pod yield (105.0 q ha-1) as compared to other treatments. The maximum net return (Rs. 337326.5 ha-1) was recorded with 40 ppm NAA with B: C ratio of 3.65 followed by 30 ppm NAA and 20 ppm NAA. The lowest net income (Rs. 162382.5 ha-1) and B: C ratio (1.76) was obtained from control. The spraying of NAA was found superior in terms of yield and yield attributes as well as benefit cost ratio followed by GA3 and salicylic acid.

Efficacy of various doses of salicylic acid, naphthalene acetic acid and gibberellic acid on vegetative growth and pod yield of broad bean (Vicia faba L.)

To investigate the efficacy of various doses of plant growth regulators on vegetative growth and pod yield of broad bean (Vicia faba L.), a field experiment was accomplished at Vegetable Research Farm, B.H.U., Varanasi during the winter season of 2019-20. Ten treatments were evaluated in randomized block design with three replications. Results indicated that the growth parameters like plant height, number of branches/plant significantly increased with foliar spray of gibberellic acid followed by NAA and salicylic acid. The yield attributes like pod width, fresh pod weight, number of pods/plant as well as fresh pod yield significantly enhanced by NAA followed by gibberellic acid and salicylic acid with various concentrations, respectively. The foliar spraying of 120 ppm GA3 tended to produce plant with maximum height (116.4 cm), number of branches/plant (6.3), pod length (7.5 cm), number of seeds/pod (4.6) as well as early 50 % flowering (57.3 days) whereas, spraying of 40 ppm NAA exhibited the maximum pod width (1.3 cm), fresh pod weight (4.6 g), number of pods/plant (87.5) as well as fresh pod yield (105.0 q ha-1) as compared to other treatments. The maximum net return (Rs. 337326.5 ha-1) was recorded with 40 ppm NAA with B: C ratio of 3.65 followed by 30 ppm NAA and 20 ppm NAA. The lowest net income (Rs. 162382.5 ha-1) and B: C ratio (1.76) was obtained from control. The spraying of NAA was found superior in terms of yield and yield attributes as well as benefit cost ratio followed by GA3 and salicylic acid.

Effect of Plant Growth Regulator on Growth, Yield and Catechin Content of Tea (Camellia sinensis (L.) O.Kuntze)

Catechins are one of the secondary metabolites contained in tea leaves. Cultivation practices such as pruning affect the shoot production and quality of tea yield. The use of plant growth regulators is a new breakthrough in tea plant engineering. This research aims to determine the interaction effect of type, height of pruning, and concentration of Benzil Amino Purine (BAP) and Gibberellin (GA) concentrations on tea plants' growth and catechin content after pruning. The experiment was conducted at Tea and Cinchona Research Centre Gambung in June 2018 until October 2018, with a split-plot design consisted of three factors as followed: main factor (a) type of pruning (clean and lung pruning); subfactor (b) pruning height (40 cm, 50 cm, and 60 cm); sub-sub factor (h) plant growth regulator (0 ppm, 60 ppm BAP, 50 ppm GA, 60 ppm BAP + 50 ppm GA). The result showed that 60 cm pruning and 60 ppm BAP in the third month after pruning significantly affected the chlorophyll content index (91,58I cci). There was an interaction between the pruning height of 60 cm and 50 ppm GA on fresh shoots weight per bush on the fourth plucking. Based on the response curve, at clean pruning, the optimum value at pruning height of 51.5 cm and 66,63 ppm BAP contributes to the catechin content of 1.88% while at lung pruning, the minimum value pruning height of 50.73 cm and 7.238 ppm with catechin content of 0.776%.

Effect of Plant Growth Regulators on Growth and Quality Flower Production of Chrysanthemum (Chrysanthemum Indicum L.)

A field study was conceded to assess the effect of plant growth regulators on growth and quality flower production of chrysanthemum at Horticulture Research Centre (HRC), Gazipur, Bangladesh. The experiment was laid out in Randomized Complete Block Design (RCBD) with ten (10) treatments and three replications. The treatments of plant growth regulators concentration were T1-50 ppm GA3, T2-100 ppm GA3, T3-150 ppm GA3, T4-400 ppm CCC, T5-600 ppm CCC, T6-800 ppm CCC, T7-250 ppm MH, T8-500 ppm MH, T9-750 ppm MH and, T10-Control. The maximum spreading of plant (27.0 cm) was observed when plants were treated with GA3 @ 150 ppm where the minimum plant spread (16.8 cm) was recorded in plants treated with CCC @ 800 ppm. The higher number of suckers (33) per pot was produced when pots were treated with GA3 @ 150 ppm whereas, application of CCC at three different concentrations produced lower number of suckers. The highest number of flower (40) was recorded with 150 ppm GA3, where minimum number of flowers (25) per pot in 800 ppm CCC. The plants sprayed with 50 ppm GA3 took 48 days to flower initiation, whereas, it took 70 days with 750 ppm MH. the highest plants recorded (7.40 cm) with 800 ppm CCC, whereas, lowest size (6.50 cm) was obtained with the application of 500 ppm MH. The maximum vase life of flowers was recorded for the treatment 800 ppm CCC (15 days), which was at par with 13 days vase life obtained by spraying 600 ppm CCC. Therefore, it is concluded that the GA3 acted as growth promoter and the CCC acted as growth retardants on yield and quality of chrysanthemum.

In-vitro regeneration in long-day garlic (Allium sativum)

The cloves of garlic (Allium sativum L.) cultivar Mukteshwar Local, after disinfection, were sprouted under in-vitro condition (85.00% sprouting) on MS medium containing 2 mg/l GA3. The cloves were soaked in 100 ppm GA3 solution for 24 hr. Maximum number of shoot buds (7.0) was recorded in treatment containing MS + 4.0 ppm BAP + 1.0 ppm NAA. Among different treatments for shoot multiplication, treatment MS+5.0 ppm BAP+ 1.0 ppm KIN + 0.5 ppm GA3 was the best. The number of shoots also varied with the level of sugar, light intensity and, light and dark cycle on shoot multiplication. They multiplied best in 30 g/l sucrose, 5000 lux light intensity and 16:8 hr of light and dark cycle. The developed protocol may be used for mass multiplication of garlic cultivars as well as regeneration of genetically transformed cell/tissue.

RAISING AND IMPROVING THE PRODUCTIVITY OF THE WASHINGTON NAVEL ORANGE TREES PLANTED IN THE NEWLY RECLAIMED LANDS BY FOLIAR SPRAY WITH GIBBERELLIC ACID

Fruit drop and quality are the most important factors in Washington navel orange production and exporting potential. This study was done at a private farm located in Sadat district, throughout the two seasons of 2020 and 2021 on Washington navel orange trees 20 years old was planted in sand soil. Three different concentrations (0.0, 5.0, 15.0 and 25.0 ppm) of Gibberellic acid (GA3) were applied as foliar spray at full bloom stage of orange cultivars. To determine the association of GA3 with fruit set and fruit drop. The obtained results showed that GA3 sprays at 25 ppm were more effective compared with other treatments and control in term of fruit set, retention, and yield as number or weight (Kg) /tree, improved the yield as well as the physical and chemical fruit characteristics, decreased drop. It might be recommended that foliar spraying with 25 ppm GA3 gave the best values of yield (kg) /tree, fruit physical and chemical properties.

Effect of Priming on Vigor of Germinated Chili (Capsicum annum L.) Seeds in Aluminium Stress Conditions

Seed germination in ultisol is a problem. Ultisol has a low pH, poor in nutrients and organic matter, and high Al content. The low physiological quality of seeds is also a limiting factor. The purpose of this study was to determine the effect of priming on the seed vigor of two chili varieties whose seeds have expired and have not expired. This experiment consisted of 2 experiments, namely Experiment 1, which used seeds that had expired (deteriorating), and Experiment II, which used seeds that had not expired (non-deteriorating). This study was structured using a completely randomized design (CRD) which was repeated three times. This experiment is factorial. The first factor is priming, consisting of five levels: control, immersion in water, 30% PEG, 50 ppm GA3, and 1% KNO3. At the same time, the second factor in the first experiment was the seeds of the Tanjung 2 and Kencana varieties that had expired (deteriorating). In the second experiment, the second factor was the seeds of the Tanjung 2 and Kencana varieties that had not expired (non-deteriorating). The data obtained were analyzed using the R statistic program with a 5% HSD test. The results showed that priming with 50 ppm GA3 and 1% KNO3 increased the vigor of seeds that had expired (deteriorating). Meanwhile, priming with water and 1% KNO3 increased the vigor of seeds that had not yet expired (deterioration). The Kencana variety has a higher vigor than the Tanjung 2 variety on expired seeds. In seeds that have not yet expired, both varieties have the same good vigor.

Pengaruh Kombinasi Zat Pengatur Tumbuh terhadap Perkecambahan dan Inisiasi Tunas Kurma (Phoenix dactylifera L.) Kultivar Sukari

The study was conducted to determine the effect of several compositions of growth regulators (PGR) on germination and shoot initiation of dates (Phoenix dactylifera L.) in vitro. The study consisted of 2 experimental stages. The first phase of the study was aimed to determine the effect of the addition of Gibberellin PGR on the length of time the sprouts appeared, the number of explants that germinated, and the length of the sprouts produced. The second stage of the research was to determine the combination of PGR Indhol Acetic Acid (IAA) and Benzyl Amino Purine (BAP) which was able to initiate the emergence of shoots in the hypocotyl of dates. The study was designed using a completely randomized design (CRD). The first experiment consisted of 3 media treatments, namely: agar without additional ZPT (GA0); agar medium with 50 ppm GA (GA1); and agar medium with 100 ppm GA (GA2). Each media treatment consisted of 5 seeds and was repeated 3 times. The second stage of the experiment was designed in a completely randomized design with 5 media treatments, namely: P0 (MS medium without PGR); P1 (MS + 1 ppm IAA + 1 ppm BAP); P2 (MS + 2 ppm IAA + 1 ppm BAP); P3 (MS + 3 ppm IAA + 1 ppm BAP); P4 (MS + 1 ppm IAA + 2 ppm BAP); and P5 (MS + 1 ppm IAA + 3 ppm BAP). Each treatment consisted of 5 explants and repeated 3 times. Parameter observation data were analyzed by Analysis of Variance (ANOVA) and if significant results were obtained, continued with the Least Significant Difference (BNT) further test. The results of the first experimental data analysis showed that the treatment with 50 ppm GA3 significantly shortened the time of emergence of sprouts to 10 days and the number of explants that germinated on average was 4.5 explants. The results of observations and data analysis in the second experiment showed that the combination of IAA and BAP ZPT were significantly able to induce shoot formation on P4 and P5 media, which were 2.83 and 1.3 explants that formed shoots, respectively. Treatment with P4 was able to significantly increase the number of shoots produced by an average of 2.63 shoots per explant.

Enhancing Mulberry (Morus alba, Linn.) Canopy Regrowth using Gibberelic Acid (GA3) and height Pruning Techniques

ABSTRACT
 Effects of pruning and growth regulator application on plant regrowth are significant to mulberry plant production. The utilization of different levels of gibberellic acid concentration(GA3) and height pruning technique investigated in mulberry 'Batac' variety in a mulberry plantation located in Ilocos Sur to determine its effects on plant regrowth in terms of the number of days to budding, number, and length of shoots, leaf senescence, biomass herbage, leaf growth ratio, and net assimilation rate, There were two height pruning strategies implemented like 0.50m and 0.75m and four different GA3 concentration like 0 ppm, 100 ppm, 200 ppm, and 300 ppm laid out in factorial randomized complete block design with three replications. The investigation revealed that mulberry plants applied with 300 ppm gibberellic acid yielded effective extensive leaf area in contrast to other treatments, including the treatments with no GA3 application. The application of GA3 on the mulberry plant after pruning either 0.50m or 0.75m advances plant growth in leaf augmentation and leaf deterioration. 300 ppm GA3 concentration produced the highest biomass herbage and yielded the highest mulberry foliage but enhanced leaf senescence tantamount to its speedy decline. There is no significant interaction between pruning heights and the different concentrations of GA3 applied to the mulberry plants. The highest profit was established by the highest concentration of GA3 with the highest net farm income, benefit-cost ratio, and rate of return per ¼ hectare mulberry farm.
 
 Keywords: height pruning, regrowth, assimilation rate, leaf deterioration, leaf growth ratio. Mulberry

Yield Performance of Mustard Using Different Concentrations of Gibberellic Acid (GA3)

An experiment was conducted at the Crop Botany Field Laboratory, Department of Crop Botany, Bangladesh Agricultural University, Mymensingh during November 2007 to March 2008 to evaluate the effects of Gibberellic acid (GA3) on yield performance and siliqua shattering of mustard (var. BINA shorisha-6). Four concentrations of GA3 viz. 0, 25, 50 and 75 ppm were sprayed on canopy at 30 days after sowing. The experiment was laid out in a Randomized Complete Block Design (RCBD) with three replications. The results showed that different levels of GA3 significantly influenced the number of siliqua/plant, number of seeds/siliqua, percentage of shattered siliqua/plant, number of flowers/plant, setting of siliqua/plant (%), seed weight/plant and harvest index. The GA3 at 50 ppm significantly increased the number of fertile siliqua/plant, number of flowers/plant, setting of siliqua/plant (%), number of seeds/siliqua, seed weight/plant and harvest index. The highest seed yield/plant was recorded from 50 ppm GA3 application at optimum harvest date. The variety incurred 47.29% yield loss due to shattering of siliqua when harvested 10 days after optimum date without application of hormone but loss was reduced to 15.34% with the application of 50 ppm of GA3.

Seed germination response of Indian wild pear (Pyrus pashia) to gibberellic acid treatment and cold storage

Knowledge of seed germination behaviour of different seed sources of tree species is useful in selecting the most responsive and adaptive ones for propagation and germplasm conservation. The wild Himalayan pear (Pyrus pashia Buch-Ham ex D. Don) produces highly nutritious edible fruits that are consumed by local communities. The populations of the species are threatened due to exploitation and lack of adequate conservation programmes. The study was conducted to examine the germination response of P. pashia seeds from two sources (S1-Champawat and S2-Pithoragarh) in Uttarakhand state of India, to different GA3 treatment and also to assess the viability and longevity of the seeds in cold storage (5 °C) for three years. In both sources germination percent (GP) increased significantly under GA3 treatment and speed of germination was also enhanced (reduction in mean germination time). In Source, 1 GP increased under all GA3 application, highest being 94% under GA3 500 ppm treatment. In Source 2, GP of seeds doubled under 100 ppm GA3 treatment while its higher concentrations did not improve the germination. However, the differences observed in germination between the seed sources could be due to differences in the dormancy levels and/or sensitivity to dormancy breaking elements across their geographical range. Thus, exogenous application of GA3 is suggested for enhancing the germination in seeds of P. pashia. Seeds responded to cold storage by increased germination with duration, i.e. highest after three years in storage, indicating that the seeds got the required chilling treatment for overcoming dormancy.

Interactions of Growth Environmental and Application of GA3 Concentration On Shallot Productivity

The purpose of this study was to evaluate the combination of technology using GA3 and agro-climate-based growing environment to increase shallot production in the lowlands. The study was designed with a nested factorial design, where the replicates were nested in an agro-climatic environment. The growing environment used consists of three conditions, namely open nature (e1), screen house (e2), UV plastic (e3). Meanwhile, the GA3 concentration (g) factor used consists of 4 levels, namely 0 ppm (g0), 100 ppm (g1), 200 ppm (g2) and 300 ppm (g3). This research design will be repeated 3 times for each treatment, so that the total experimental plot is 36 experimental units. The characters observed consisted of six characters, namely the number of leaves, absorption, reflection, tuber fresh weight, tuber diameter and tuber production. The results of this study indicate that GA3 treatment and UV application are very influential in increasing the productivity of shallots. The combination of 200 ppm GA3 concentration with the use of UV is the recommended technology in shallot cultivation. The fresh weight character of the tuber is a recommended secondary character in evaluating the potential of shallot cultivation technology. Hasanuddin University, Jl. Perintis Kemerdekaan No. KM.10, Tamalanrea Indah, Kec. Tamalanrea, Kota Makassar, Sulawesi Selatan 90245.

INFLUENCE OF ORGANIC MANURES AND GIBBERELLIC ACID ON GROWTH AND YIELD OF STRAWBERRY (Fragaria X ananassa DUCH.)

A field experiment was conducted to study the effect of organic manures and growth regulators on the growth and yield of two varieties of strawberry namely ‘Sweet Charlie’ and ‘Winter Dawn’. Six treatments were taken combining three organic manures viz. Vermicompost @ 3.0 t/ha, Mustard oil cake @ 1.0 t/ha and Neem cake @ 1.0 t/ha and two concentrations of gibberellic acid (GA3) viz. 75 ppm and 100 ppm along with a control. Foliar application of GA3 was carried out at 40 and 60 days after planting whereas organic manures were applied as basal dose. Results of the study suggested that higher doses i.e. 100 ppm of GA3 along with vermicompost exhibited more vegetative growth whereas 75 ppm GA3 resulted in higher fruit set and yield in both the varieties. It was found that vermicompost @ 3.0 t/ha combined with 100 ppm GA3 recorded the highest plant height (24.7 cm and 21.4 cm) and numbers of leaves per plant (46.0 and 68.7) in both Sweet Charlie and Winter Dawn varieties, respectively. Whereas, highest fruit diameter (3.3cm and 3.4cm), fruit length (4.6cm and 4.8cm), fruit weight (18.2 g and 17.9 g), number of fruits per plant (24.6 and 32.0), yield per plant (447.8 g and 572.1 g) and yield per hectare (18.80 t and 24.03 t) were recorded under vermicompost @ 3.0 t/ha in combination with 75 ppm GA3 in both Sweet Charlie and Winter Dawn varieties, respectively. It was observed that Winter Dawn variety produced a 28.0% higher yield as compared to Sweet Charlie under the best treatment i.e. vermicompost @ 3.0 t/ha in combination with 75 ppm GA3.

Acceleration of growth in tomato seedlings grown with growth retardant

In vegetable growing, seedling is the foundation of a successful growing. Use of commercial seedlings have become more popular in recent years due to effective use of labour and land and economic concerns. It is aimed to produce small vigorous seedlings with sufficient roots and free of diseases and pests in the commercial seedling enterprises. Although certain cultural applications are used for production of small-sized seedlings, growth retarding chemicals are generally preferred due to their effective results. There are some concerns regarding on-going retarding effects of such chemicals under field conditions. In this study, it is aimed to remove the possible retarding effects provided by paclobutrazol in dosages of 0, 25, 50 and 100 ppm applied on tomato seeds in a short period of time by applying gibberellic acid (GA3) in dosages of 0, 50, and 100 ppm by spraying it on the leaves. In this study, the plant height (cm), stem diameter (mm) height to stem diameter ratio, number of blooming cluster and dry matter ratio of stem (%) were determined in the different stages of growth. Paclobutrazol ensured a height control of 26.45%-40.85% on the height of plants in the seedling period depending on the dosage, and this ratio varied by 19.51 to 45.86% under field conditions. It has been found out that effects of paclobutrazol diminished in time, and these effects were removed faster by GA3 applications. Paclobutrazol, as opposed to GA3, decreased the height to stem diameter ratio and induced formation of a stronger seedling. Paclobutrazol increased the number of blooming clusters, whereas GA3 had no significant observable effect on the number of blooming cluster. It has been concluded that 50 ppm paclobutrazol can be used for height control of the seedling in terms of growth and flowering, and 100 ppm GA3 should be applied for quality plant growth and to remove possible retarding effects.

Effects of pre-treatments in relation to breaking of dormancy of endemic Hypericum adenotrichum Spach. seeds

Hypericum adenotrichum Spach. (Hypericaceae, Clusiaceae) is an endemic species to Turkey, which is one of the commonly used species in pharmacological research. We studied seed germination characteristics. The effects of dry storage (3, 9, 12 month), moist chilling (3, 6, 9, 12 month), scarification (H2SO4, sand paper), tap water, hormone (250, 500, 1000 ppm GA3), different temperature (15/10, 20/10 and 25/15 °C) and light (photoperiod, darkness) treatments on seed germination of H. adenotrichum seeds collected from subalpine belt of Uludağ Mountain were examined. Favourable germination temperature for H. adenotrichum is 20/10 °C and no light is required for the seed germination. Seeds of species have physiological dormancy. GA3 without any other treatment was not successful enough to break the dormancy status alone. Scarification by sulphuric acid and 1000 ppm GA3 combination is the most effective way for germination of H. adenotrichum seeds. Germination requirements of H. adenotrichum have not been studied previously and the data obtained could be used in the ex-situ protection of H. adenotrichum.

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.

Effects of brassinosteroids and gibberellin on water uptake and performance of soya bean seeds under different temperatures

Low temperature has negative effects on seed performance and seedling growth in soya bean, reducing stand establishment. It was hypothesised, that seed treatment with plant hormones could improve seed imbibition and performance at low temperature. Therefore, the effects of 24-epibrassinolide (EBL) and gibberellic acid (GA3) on soya bean seed germination were studied. Seeds of 'CM60' and 'CM0701-24' were imbibed with 0.25 or 0.50 ppm EBL, 50 or 100 ppm GA3, or distilled water at 10, 15, 20 and 25°C. The seed imbibition patterns of the two soya bean varieties followed a similar trend. Low temperature delayed seed imbibition resulting in longer time to reach the end of phases 1 and 2 of seed germination as compared with high temperature. Soya bean seeds treated with 50 or 100 ppm GA3 showed increased germination index, shoot and root length and reduced mean germination time. Thus, 50-100 ppm GA3 could be used as a pre-soaking seed treatment to improve soya bean seed and seedling performance under low temperature.

​Influence of Pre-sowing Treatments, Sowing Positions and Age of Stones after Extraction from Fruit on Germination and Vigour of Mango

Background: Mango stones are in general recalcitrant. Moreover, they are available only during April- May months which are the drier parts of the year. So stone germination and plant vigour are very low. Proper seed orientation, age of stones after extraction from fruit and pre-sowing treatments need to be taken into consideration for inducing early germination, boosting growth, enhancing the seedling vigour and reducing the mortality. Methods: The experiment was laid out in factorial completely randomized design with forty two treatment combinations replicated thrice. The treatments were comprised of two sowing positions viz., flat and stalk end up, three age of stones after extraction from fruit, viz., fresh extracted, 10 days and 20 days after extraction and seven pre-sowing treatments viz., 100 ppm GA3, 200 ppm GA3, 1 ppm KNO3, 2 ppm KNO3, cow dung slurry, water, control and their combinations. Result: Stalk end up sowing of freshly extracted stones pre-treated with 200 ppm GA3 for 24 hours recorded better germination and vigour of mango seedlings.