Flower Stalk Research Articles

Produção e qualidade de hastes florais de gérbera em substrato suplementado com diferentes doses de nitrogênio e cálcio

Abstract Success in production and quality of gerbera flower stalks over time depends on environmental factors and on appropriate fertilization procedures. The objective of the present work was to evaluate the production and quality of flower stalks of gerberas as cut flower cultivated for 28 months (with 25 months of harvest) in a pine bark-based substrate supplemented with different doses of nitrogen and calcium. The experiment was conducted in a greenhouse. Three doses of nitrogen (N) (0.07 g, 0.15 g and 0.20 g L-1 substrate) and three doses of calcium (Ca) (0.02 g, 0.03 g and 0.04 g L-1 substrate) were applied every 15 days along the cultivation period. The control was considered an additional treatment to which neither N nor Ca was supplemented to the plants in the pots. Highest flower yields and best flower quality were obtained in months in which the temperatures were in the range of 20 ºC to 25 ºC. The highest number of floral stalks and the largest diameter of the capitulum had a significant quadratic adjustment according to N doses. The maximum values were obtained with 0.14 g of N L-1 substrate. Whereas for Ca fertilization, a significant positive linear adjustment was determined, i.e., the highest values were obtained with the highest dose (0.04 g Ca L-1 substrate). There was a monthly variation in the yield and quality of cut gerberas grown in commercial substrate based on pine bark regardless of the different doses of nitrogen and calcium used in the experiment.

Effect of Plant Growth Regulators Giberellic acid (GA3) And Salicylic Acid (SA) on Growth and Yield of Carnation (Dianthus caryophyllus) under Naturally Ventilated Polyhouse

The present investigation entitled “Effect of plant growth regulators Gibberellic Acid (GA3) and Salicylic Acid (SA) on the growth and yield of carnation under naturally ventilated polyhouse”, was carried out during November, 2021 to April 2022 in, Naturally Ventilated Polyhouse, Department of Horticulture, Naini Agricultural Institute, SHUATS, it was concluded that the plant growth regulators treatments rendered their significant effect on almost all the growth, flowering and yield characters as well as quality of carnation. The treatment T3 i.e. application of GA3 @ 200 ppm was found superior in terms of Plant height (102.27cm), number of leaves (203.67), number of shoots (7.67), internodal length (7.73cm), number of internodes per shoot (17), bud length (10cm), bud diameter (2.87cm), flower diameter (6.80cm), flower length (5.67cm), flower stalk length (96.93cm), vase life (10.33), number of cut flower stalks per plant (7.00) and number of cut flower stalks per square meter (175). However, plants treated with SA @ 120ppm took minimum days for bud initiation (112.67 days) and the days taken to bud opening (24.67). Among the different treatments the highest Gross return (Rs/200m2) (7,00,000), Net return (441565), benefit cost ratio (2.70) was obtainedunder the use of GA3 @ 200 ppm (T3).

The Utilization of Various Types of Organic Fertilizer and Trichoderma on Increasing The Production and Quality of Chryshone Cut Flowers

Horticultural commodities, especially ornamental plants, have high economic value in the market. It is necessary to research the introduction of appropriate technology in increasing the intensity of chrysanthemum cultivation such as the use of domestically created organic fertilizers and Trichoderma, which are formulated with local resources in chrysanthemums to improve quality and added value and utilize the potential of agricultural resources that are easy to apply following the ability of farmers and have a real impact on increasing income. The purpose of this research is to obtain a package of organic matter and Trichoderma that is suitable for the agro-climate, thus farmers will be interested in adopting the technology and developing it widely into their production system. The method used is field research in a greenhouse using a factorial randomized block design, with two factors that will be used to achieve the goal, namely the use of various types of organic fertilizers and the administration of Trichoderma doses. If the single treatment has a significant or very significant effect, then continue with the 5% BNT average value test, whereas if there is an interaction between the two factors, it is tested with Duncan't 5%. Based on the results of the study, all types of organic fertilizers, namely organic cow manure, organic pig manure, and organic goat manure combined with Trichoderma were able to suppress rust disease in chrysanthemums and increase the production and quality of chrysanthemums. Goat dung fertilizer and a dose of 5 tons-¹ ha of Trichoderma tended to produce flower stalk height, flower stalk weight, stem diameter, flower diameter, economical flower fresh weight and resulted in the lowest percentage of leaves affected by rust disease.

Genetic variability in Mysuru jasmine (Mysuru mallige): A GI crop of Mysuru

At the college of Horticulture, Mysuru, Karnataka, the study was conducted during 2018 kharif using RBD with two replications. Quantitative characters namely petiole length, leaf length, leaf breadth, bud length, bud breadth, flower diameter, flower stalks length or pedicel length, calyx length, the number of sepals/ calyx teeth, the number of whorls, the number of petals, petal length, the number of stamens, length of the anther, length of the filament, length of the style, length of the stigma, length of the corolla tube and flower bud weight were recorded. High (>20%) genotypic coefficient of variation (GCV) and phenotypic coefficient of variation (PCV) was observed for bud length, bud breadth, the number of whorls, the number of petals, pedicel length, length of corolla tube, length of filament, length of style, length of stigma and flower bud weight. Moderate (10 to 20%) GCV and PCV were observed for petiole length, leaf length, leaf breadth, flower diameter, calyx length, the number of calyx teeth, petal size and the number of stamen and length of the anther. The phenotypic co-efficient of variation was more than the genotypic co-efficient of variation for all characters studied. The  higher (>20%) values of genetic advance over mean (GAM) coupled with very high (>80%) estimates of heritability were observed for characters viz., bud length, bud breadth, flower diameter, calyx length, the number of calyx teeth, the number of whorls, the number of petals, petal size, pedicel length, length of the corolla tube, the number of stamens, length of anther, length of the filament, length of the style, length of the stigma and flower bud weight. Moderate heritability (40-60%) with low GAM was observed for petiole length. The variance due to genotypes was highly significant for all the characters except for length of the leaf. Keywords: Mysuru mallige, genetic advance heritability, PCV, GCV

Effect of Crop Geometry and Age of Seedlings on Its Growth, Flower Yield and Quality of Statice (Limonium sinuatum L.) under Prayagraj Agro Climatic Conditions

The objective of this study is to find out the most suitable treatments for plant growth and flower yield and quality of Limonium (Limonium sinuatum L.) under prayagraj agro climatic conditions. The study was carried out at Experimental field, Department of Horticulture, Naini Agriculture Institute, Sam Higginbottom University of Agriculture, Technology and Sciences, Prayagraj (U.P.), India during Rabi season 2021-2022. The experiment was laid out in a Factorial randomized block design (FRBD) with 8 treatments which is replicated thrice. The first factor consists of four different levels age of seedlings i,e. 25,30,35,40 days old seedlings, second factor with two different spacings 45×60 cm and 30×45 cm. In Growth parameters, T7 (40 days seedlings + spacing of 45×60 cm) recorded significantly highest number of leaves (80.49), leaf length (32.20 cm), plant spread (45.65 cm2) Whereas, plant height was recorded significantly highest (84.80 cm) in T6 (35 days seedlings + spacing of 30×45 cm). In photosynthetic characteristics, the maximum leaf area (66.09 cm2), leaf weight (24.94 gm) and chlorophyll content (97.90 SPAD UNITS) was recorded in T7 (40 days seedlings + spacing 45×60 cm). In flowering parameters, the minimum number of days for flower stalk initiation (47.28 days) and flower duration (45.72 days) was recorded significantly in T7 (40 days seedlings + spacing of 45×60 cm) whereas, the length of flower stalk was recorded significantly highest (80.07) in T6 (35 days seedlings + spacing of 30×45 cm).The maximum yield with superior quality of flower stalks/plot was obtained significantly highest (80.22) in T6 (35 days seedlings + spacing of 30×45 cm). In post-harvest parameters the vase life of statice flower placed in water recorded maximum (8.69 days) in T6 (35 days seedlings + spacing 30x45 cm), whereas vase life of statice flower placed in 2% sucrose (14.35 days) and self-life (63.33 days) of flower was recorded maximum in T7 (40 days seedlings + spacing of 45x60 cm).

Altered within- and between-host transmission under coinfection underpin parasite co-occurrence patterns in the wild

Interactions among parasite species coinfecting the same host individual can have far reaching consequences for parasite ecology and evolution. How these within-host interactions affect epidemics may depend on two non-exclusive mechanisms: parasite growth and reproduction within hosts, and parasite transmission between hosts. Yet, how these two mechanisms operate under coinfection, and how sensitive they are to the composition of the coinfecting parasite community, remains poorly understood. Here, we test the hypothesis that the relationship between within- and between-host transmission of the fungal pathogen, Phomopsis subordinaria, is affected by co-occurring parasites infecting the host plant, Plantago lanceolata. We conducted a field experiment manipulating the parasite community of transmission source plants, then tracked P. subordinaria within-host transmission, as well as between-host transmission to naïve recipient plants. We find that coinfection with the powdery mildew pathogen, Podosphaera plantaginis, causes increased between-host transmission of P. subordinaria by affecting the number of infected flower stalks in the source plants, resulting from altered auto-infection. In contrast, coinfection with viruses did not have an effect on either within- or between-host transmission. We then analyzed data on the occurrence of P. subordinaria in 2018 and the powdery mildew in a multi-year survey data set from natural host populations to test whether the positive association predicted by our experimental results is evident in field epidemiological data. Consistent with our experimental findings, we observed a positive association in the occurrence of P. subordinaria and historical powdery mildew persistence. Jointly, our experimental and epidemiological results suggest that within- and between-host transmission of P. subordinaria depends on the identity of coinfecting parasites, with potentially far-reaching effects on disease dynamics and parasite co-occurrence patterns in wild populations.

Utilization of Chrysanthemum Leaf Extract and Molasses in the Cultivation of Chrysanthemum Cut Flowers

This research aims to determine the effect of extraction of chrysanthemum and molasses leaves and their interactions on growth and yield in the cultivation of chrysanthemum cut flowers. The research method uses a randomized block design of factorial patterns with two factors, namely: extract of chrysanthemum leaves consisting of four levels each: 250 g l-1, 500 g l-1, 750 g l-1 and 1000 g l-1, as well as molasses consists of three levels respectively: 5 ml l-1, 10 ml l-1 and 15 ml l-1. The combination treatment of 12 was repeated 3 replications. The results showed that the interaction between the extraction of chrysanthemum leaves and molasses had not significantly affected on all the observed variables. The extraction treatment of chrysanthemum leaves has a significant effect (P˂0.05) to very significant (P ˂ 0.01) on all observed variables except at maximum plant height and stem diameter. The extraction treatment of chrysanthemum leaves 1000 g l-1 resulted in the average fresh weight of flower stalks and the highest economic fresh weight of 133.67 g and 110.27g respectively. There was an increase in yield by 24.99% and 26.71% when it was compared to the lowest treatment. Molasses treatment exerts a significant effect (P ˂ 0.05) to a very significant (P ˂ 0.01) influence on all observed variables, except on the diameter of the rod. Molasses treatment of 15 ml l-1 resulted in an average fresh weight of flower stalks and the highest economic fresh weight of 120.79 g and 94.51 g compared to the lowest treatment, and there was an increase in yield by 11.86% and 25.51% compared to the lowest treatment

Effect of silver nanoparticles on sterilization of different explant sources of Gerbera jamesonii cultured in vitro

In this study, silver nanoparticles effects on the sterilization of different sources of explants (young leaves, young flower stalks and young flower buds) of Gerbera as well as on the in vitro morphogenesis and their growth were investigated. The explants were sterilized and cut transversally (1 mm) with the flower stalk, square (0.5 × 0.5 cm) for the leaf sample, longitudinally (0.5 mm) for the flowers (removed the petals) and cultured on MS medium; then, the explants (contamination-free or no browning/necrosis) were transferred into MS medium supplemented with 0.02 mg/L TDZ plus 0.8 mg/L adenine, 10% coconut water, 30 g/L sucrose and 8 g/L agar in 15 days. The results showed that AgNPs at the appropriate concentration and duration treatment was effective in explant sterilization of flower bud (0.02% AgNPs and 20 min), flower stalks (0.02% AgNPs and 30 min) and young leaves (0.05% AgNPs and 20 min) after 15 days of culture. In addition, 3 types of morphogenesis including callus induction, somatic embryogenesis and direct shoot regeneration of explants derived from sterilization by AgNPs were improved as compared to that of HgCl2. In addition, research on the optimal medium for shoot multiplication, rooting as well as evaluation of acclimatization and the growth at the greenhouse were also studied. Results showed that MS medium supplemented with 2 mg/L NAA combined with 0.5 mg/L BA and 2 mg/L KIN is suitable for shoot multiplication; meanwhile, MS medium supplemented with 2 mg/L NAA improved rooting ability as well as quality of plantlets and to improving survival rate and acclimatization of Gerbera cultured in vitro.

Pemberian air rebusan kentang pada media Murashige-Skoog terhadap pertumbuhan protokorm anggrek sendu (Grammatophyllum stapeliiflorum) secara in vitro

Grammatophyllum stapeliiflorum is one of the most popular orchid species because of its beauty and is characterized by the shape of the flower stalk that sticks down and the brown flowers with white and yellow spots that look like drops of water or sad. This type of orchid is almost extinct and is rarely found in its natural habitat, so it is necessary to perform in vitro propagation of orchids. The culture in vitro method is one of the most effective methods for propagating rare orchids. This study aimed to determine the effect of adding potato water on protocorm growth and determine the best concentration for the growth of G. stapeliiflorum protocorm in vitro. This study used a Completely Randomized Design (CRD) with the addition of potato water (concentrations 0, 50, 100, 150, and 200 ml/L) on Murashige-Skoog (MS) medium. The results showed that the percentage of live explants was 100% in all treatments. The addition of potato water to MS medium had no effect on the percentage of live explants but still affected the growth percentage of Protocorm-like bodies (PLBs) in vitro. The best concentration of potato water for the protocorm growth of G. stapeliiflorum in vitro to MS medium was at a concentration of 150 ml/L, which was indicated by the highest percentage of PLBs growth at 100% and the color of PLBs green (2.5GY 6/8) compared to other potato water treatments and controls.

Attracted to feed, not to be fed upon – on the biology of Toxomerus basalis (Walker, 1836), the kleptoparasitic ‘sundew flower fly’ (Diptera: Syrphidae)

AbstractThe complete life history of the kleptoparasitic ‘sundew flower fly’, Toxomerus basalis, is presented and illustrated. Adults of this species are photographed alive for the first time, including video recordings of larval and adult behaviour. Adult flies of both sexes visit Drosera (sundews) and show territorial behaviour around the plants, avoiding the dangerous sticky traps and demonstrating recognition of their larval host plant. Females lay eggs directly on non-sticky parts of the Drosera host plants, such as on the lower surface of the leaves and flower stalks, but apparently also on other plants growing in close proximity with the sundews.

EVALUATION OF THE EFFICIENCY OF ONION (Allium cepa L.) SETS TREATED WITH ASCORBIC ACID AND SALICYLIC ACID IN STIMULATING GROWTH AND SEED PRODUCTION

Onion (Allium cepa L.) is one of the economical cultivated crops and is consumed heavily worldwide. The demand fOnion (Allium cepa L.) is one of the economical cultivated crops and is consumed heavily worldwide. The demand for onion seeds is high as it loses viability within a year. In Iraq, onion production has been limited due to the lack of good quality of seeds. Therefore, this study was aimed to improve seed quality and productivity of onion local white cultivar by using optimum onion sets size and priming with phytohormones. A field experiment was carried out in the Grrdarash field belonging to the Salahaddin University, Erbil. A split-plot in Randomized Complete Block Design (RCBD) was applied with three replicates. Onion sets >6.0 cm, large diameter and 4-6 cm, medium diameter, was selected. The bases of the sets were soaked in ascorbic acid (AsA) (1 and 2 mM), salicylic acid (SA) (0.5 and 1 mM) and control (water only) for 24 hours at 4°C. The results show that the emergence rate of flower stalk per day, the rate of umbel opening per plant, the number of flower stalks per plant, the number of flowers per umbel and seed yield (t.h-1) were increased statistically and significantly by using the large onion sets. AsA and SA treatments show their significant effect on flowering and seed quantity. A positive relationship was found between the aforementioned treatments and onion seed yield. Therefore, further studies are required to evaluate the effectiveness of a natural product that has the same properties as AsA and SA on the growth and quality of vegetable crops.

Characterization of cultivated pumpkin (Cucurbita moschata Duchesne) landraces for genotypic variance, heritability and agro-morphological traits

Cucurbita moschata (Pumpkin) is a multipurpose species whose fruits and sometimes oil seeds are used for various purposes. It is low in calories and is a significant source of income. Despite the great potential of the pumpkin production and usage, there is no attention to establish the varieties grown in Benin for proper documentation. Therefore, the present study was carried out to (i) evaluate the agro-morphological variability of pumpkin accessions collected in Benin and (ii) investigate heritability, genetic gain, phenotypic and genotypic variances of the agronomic traits. Six landraces from one hundred and twenty accessions collected in Benin were sown and characterized. The agronomic experiment was laid out in a complete randomized block design with three replicates. Out of the twenty-seven quantitative descriptors measured, fifteen were found to be significant. The 50% emergence time (p = 0.03), the number of female flowers (p = 0.02), the seed width (p = 0.05) and the ratio seed width and length (p = 0.01) were significant. A highly significant difference was observed with the days to 50% flowering and the length of male flower stalks (p = 0.002), the average weight of one hundred seeds (p = 0.009). Fruit set at 50%, length of female flower peduncle, number of male flowers, mean fruit weight, fruit length, fruit diameter, average number of seeds per fruit and seed length were very highly significant (p < 0.001). Fruit color and shape, seed color and leaf color showed phenotypic variability. A positive correlation (r = 0.76; p < 0.05) was observed between average fruit weight and average number of seeds per fruit. Principal component analysis and Hierarchical Ascending Classification revealed three classes. Estimates of the phenotypic coefficient of variation were higher than estimates of the genotypic coefficient of variation for most characters. High heritability was observed for fruit diameter (96.73%), average fruit weight (96.46%) and fruit length (94.64%). High heritability associated with high genetic advance was observed for these traits. In sum, the genetic diversity observed within the landraces of pumpkin shows that there is possibility for further selection.

Coinfection with a virus constrains within-host infection load but increases transmission potential of a highly virulent fungal plant pathogen.

The trade‐off between within‐host infection rate and transmission to new hosts is predicted to constrain pathogen evolution, and to maintain polymorphism in pathogen populations. Pathogen life‐history stages and their correlations that underpin infection development may change under coinfection with other parasites as they compete for the same limited host resources. Cross‐kingdom interactions are common among pathogens in both natural and cultivated systems, yet their impacts on disease ecology and evolution are rarely studied. The host plant Plantago lanceolata is naturally infected by both Phomopsis subordinaria, a seed killing fungus, as well as Plantago lanceolata latent virus (PlLV) in the Åland Islands, SW Finland. We performed an inoculation assay to test whether coinfection with PlLV affects performance of two P. subordinaria strains, and the correlation between within‐host infection rate and transmission potential. The strains differed in the measured life‐history traits and their correlations. Moreover, we found that under virus coinfection, within‐host infection rate of P. subordinaria was smaller but transmission potential was higher compared to strains under single infection. The negative correlation between within‐host infection rate and transmission potential detected under single infection became positive under coinfection with PlLV. To understand whether within‐host and between‐host dynamics are correlated in wild populations, we surveyed 260 natural populations of P. lanceolata for P. subordinaria infection occurrence. When infections were found, we estimated between‐hosts dynamics by determining pathogen population size as the proportion of infected individuals, and within‐host dynamics by counting the proportion of infected flower stalks in 10 infected plants. In wild populations, the proportion of infected flower stalks was positively associated with pathogen population size. Jointly, our results suggest that the trade‐off between within‐host infection load and transmission may be strain specific, and that the pathogen life‐history that underpin epidemics may change depending on the diversity of infection, generating variation in disease dynamics.

Effect of Antioxidants, Culture Conditions and Frequency of Subculture to Control Phenols during in vitro Culture of Phalaenopsis Hybrid Cultivar ORIANA

The present study was conducted to control phenols in the media during in vitro cultures using flower stalk explants of Phalaenopsis hybrid cultivar Oriana. MS medium + BAP (1.00 ppm) + NAA (0.50 ppm) + 3% sucrose (w/v) was used commonly for all the treatment. Results revealed that inclusion of 500 ppm citric acid in the media, rinsing the explants with citric acid 500 ppm for 20 minutes before inoculation, keeping culture in dark for 20 days and sub-culturing at 4, 6 and 8 days after inoculation were found to be significantly reducing the browning intensity (very low browning) in medium. The explants remained green even after 4th week of culture with significantly minimum percentage of blackening of cultures (10.00%), minimum percentage of dead cultures (20.00%) and maximum percentage of cultures survived (80.00%).Inclusion of 500 ppm citric acid in the media, rinsing of explant with citric acid 500 ppm for 20 minutes before inoculation, incubating the culture in dark for 20 days and subculturing at an interval of 4, 6, and 8 day after inoculation in case of flower stalk explants were observed to control phenols in the media during in vitro cultures of Phalaenopsis hybrid cultivar Oriana.

Effect of different pesticide treatments on rose flower bud initiation, diameter, stalk length, vase life and number of flowers per plant under polyhouse condition

The overall results revealed that the treatments with Spinosad and Clothianidin were most effective against thrips by recording the lowest mean population of 2.20 and 2.68 thrips/ three leaves, respectively and were on par with each other. Days required for first flower bud initiation, rose diameter, stalk length, vase life, number of flowers per plant varied significantly due to different pesticidal treatments under polyhouse conditions. The minimum days (34.2 days) required and earliest first flower bud initiation was observed in the treatment with Spinosad 45% SC @ 0.3 ml/l (T2) was significantly superior over the rest of treatments. The next best treatment was Clothianidin which required (34.9 days) for first flower bud initiation.

Transcriptome Analysis Provides Insights into the Role of Phytohormone in Regulating Axillary Bud Development of Flower Stalk in Phalaenopsis

Transcriptome Analysis Provides Insights into the Role of Phytohormone in Regulating Axillary Bud Development of Flower Stalk in Phalaenopsis

КОМПЛЕКСНАЯ ОЦЕНКА СОРТОВ ЛИЛЕЙНИКА ГИБРИДНОГО В УСЛОВИЯХ ЛЕСОСТЕПНОЙ ЗОНЫ БАШКИРСКОГО ПРЕДУРАЛЬЯ

A comprehensive assessment and selection of the most valuable taxa suitable for use in landscaping under certain natural and climatic conditions is one of the most important tasks of introduction studies of ornamental plants. The article presents the results of a comprehensive variety assessment, a study of the seasonal rhythm of growth and development, and morphometric characteristics of 20 hybrid daylily varieties (Hemerocallis hybrida hort.) in the South-Ural Botanical Garden-Institute of UFRC RAS. An assessment of the decorative and economically valuable qualities of daylily varieties was given on a 100-point scale, including 11 traits: color, size and shape of a flower, plant habitus, height of the flower stalk, abundance of flowering, originality, reproductive ability, duration of flowering, sustainability in unfavorable conditions, resistance to diseases and pests. As a result of our variety assessment of Hemerocallis hybrida hort., the entire studied assortment was divided into 3 groups according to the prospects for use in decorative floriculture. 8 highly promising varieties (‘Bela Lugosi’, ‘Bestseller’, ‘El Desperado’, ‘Ledgewoods Jumstar’, ‘Moon Over Monteray’, ‘Pardon Me’, ‘Red Rum’, ‘Stella de Oro’) have been identified for cultivation under conditions of Bashkortostan Republic. They are distinguished by their bright color and original flower shape, abundant and long flowering, strong peduncle, and high reproductive capacity. Nine varieties are characterized by medium prospects (‘Artic Snow’, ‘Cherry Eyed Pumpkin’, ‘Final Touch’, ‘Frans Hals’, ‘Macbeth’, ‘Mini Stella’, ‘Pandoras Box’, ‘Sea of Cortez’, ‘Tooth’); 3 − are unpromising (‘Night Embers’, ‘Prince of Lemon’, ‘Strawberry Candy’). All studied varieties can be used in various types of flower decoration under the conditions of the Bashkir Cis-Urals.

Genetic variation of Dahlia cultivars evaluated in sub-tropical Himalayas and path coefficient analysis of flowering and vegetative characters

Dahlia is a popular bulbous ornamental plant being used as bedding plant, pot plant and for cut flowers. Under sub-montane, sub tropical conditions, 24 cultivars of Dahlia variabilis L. were planted in randomized complete block design and their flowering and vegetative growth characters were evaluated and genetic and phenotypic variance were estimated using ANOVA. Phenotypic and genetic coefficients of variation were recorded maximum for leaf area (34.5% and 33.5%) implies that variability is mostly controlled by the genetic component. Heritability (broad sense) was maximum for flowering duration (98.6%) followed by plant height (97.8%). Estimated genetic gain was high for leaf area (66.9%) followed by internodal length (55.2%). Flower number was found positively correlated with plant height, flower stalk length, number of side shoots, plant spread and number of leaves. Path co-efficient analysis showed that stalk length had maximum positive direct effect on number of flowers per plant (2.62) followed by days taken to bud formation (1.13), flowering duration (0.85), number of leaves (0.81), plant spread (0.78) at genetic level. The results suggest that there are sufficient genetic variation available among tested cultivars and can be used for genetic improvement of dahlia.

Performance of chrysanthemum at dark exposure under polytunnel condition

The field experiment carried out in chrysanthemum (cv. Chandrika) nursery 10 at College of Horticulture, Dapoli, Dist. Ratnagiri 2020-21 under polytunnel conditions during 2020-21 revealed that exposing chrysanthemum plants to darkness for 180 minutes using 90 per cent black shed net, showed promising results in increasing plant spread, number of branches, average leaf area, leaf area index, days required for 50 per cent flowering, flower diameter, length of flower stalk and the flower yield parameters, respectively. The shelf life of chrysanthemum flowers was extended by 24.84 days at 2°C temperature level.

Characteristics of fungi contaminant in tissue culture of Bromheadia finlaysoniana (Lind.) Miq

Generative propagation of orchid plants has problems because orchid seeds do not have endosperm that need to be multiplied using tissue culture. Contamination is a limiting factor in the multiplication of plants in tissue culture. This study describes the types of contaminants found in Bromheadia finlaysoniana callus. This research was carried out in two stages. The first stage is carried out culture of various explants of Bromheadia finlaysoniana using murashige and Skoog media with enrichment of hormone Benzylaminopurine 1 mg/l; (Naphthalene acetic acid) 0.5 mg/l; 100 mg mynositol; pyridoxine-HCl 0.5 mg/l; thiamine-HCl 0.1 mg/l; nicotinic-acid 0.5 mg/l; glycine 2 mg/l. The second stage is observed and the percentage of contaminant fungi. The observed contaminants character includes the colour, the direction of growth, and the hyphae colony's shape. Determination of contaminants type compared to the morphology of references. The result is the highest contamination in flower stalk explants, 81%; most colonies on leaf explants are 28. Contaminant fungi grow predominantly of fungi with white and grey colour and a rough surface shape. The macroscopic character of contaminant fungi in tissue cultures mostly comes from the class of Deuteromycetes and Zygomycetes. Keywords: Bromheadia finlaysoniana , contaminant, fungi, tissue culture