Growth Of Marigold Research Articles

Light quality impacts on growth, flowering, mineral uptake and petal pigmentation of marigold

Light quality has a significant impact on growth and development and time to flower in many plant species. Recently, the percentages of blue and red in narrow-band wavelengths of light from light-emitting diodes (LEDs) have been shown to impact mineral uptake, pigment development and the rate of growth and development of several plant species. The objective of this research was to evaluate the effects of light quality on shoot growth, flower development, mineral uptake and pigment content of marigold (Tagetes patula 'Safari Orange'). Plants were grown in 10-cm square pots in a greenhouse ebb and flood system with a complete nutrient solution. Plants received average day temperatures of 25°C and night temperatures of 16°C. The following light treatments were utilized in this study: 1) natural sunlight; 2) high-pressure sodium (HPS) lighting at 100 µmols m-2 s-1 intensity in addition to natural sunlight intensity; 3) LED lighting with blue and red wavelengths at 50% each and intensity at 100 µmols m-2 s-1 in addition to natural sunlight intensity; and 4) LED lighting with blue at 25% and red at 75% and intensity at 100 µmols m-2 s-1 in addition to natural sunlight intensity. Total shoot growth was twice as high in all supplemental light treatments compared to the natural sunlight treatment. Shoot growth was greater in the 25% blue/75% red LED treatment than in the HPS light treatment. The 50% blue/50% red LED treatment was not significantly different from the HPS light treatment. Plants in the 25% blue/75% red LED treatment had 15% more blooms than plants in the 50% blue/50% red LED treatment or the HPS light treatment. All supplemental light treatments produced plants with significantly more blooms than plants in the natural sunlight treatment. Plants in the LED light treatments had greater petal pigment content than plants in the natural sunlight treatment.

Effect of Arbuscular Mycorrhizal Fungi On Yield and Phytoremediation Performance of Pot Marigold (Calendula officinalis L.) Under Heavy Metals Stress

In order to study the effect of mycorrhizal fungi (inoculated and non-inoculated) and heavy metals stress [0, Pb (150 and 300 mg/kg) and Cd (40 and 80 mg/kg)] on pot marigold (Calendula officinalis L.), a factorial experiment was conducted based on a randomized complete block design with 4 replications in Research Greenhouse of Department of Horticultural Sciences, University of Tehran, Iran, during 2012–2013. Plant height, herbal and flower fresh and dry weight, root fresh and dry weight and root volume, colonization percentage, total petal extract, total petal flavonoids, root and shoot P and K uptakes, and Pb and Cd accumulations in root and shoot were measured. Results indicated that with increasing soil Pb and Cd concentration, growth and yield of pot marigold was reduced significantly; Cd had greater negative impacts than Pb. However, mycorrhizal fungi alleviated these impacts by improving plant growth and yield. Pot marigold concentrated high amounts of Pb and especially Cd in its roots and shoots; mycorrhizal plants had a greater accumulation of these metals, so that those under 80 mg/kg Cd soil−1 accumulated 833.3 and 1585.8 mg Cd in their shoots and roots, respectively. In conclusion, mycorrhizal fungi can improve not only growth and yield of pot marigold in heavy metal stressed condition, but also phytoremediation performance by increasing heavy metals accumulation in the plant organs.

Seed germination and yield of marigold (Calendula officinalis L.) as affected by biophysical priming techniques

Seed priming has been reported to enhance growth of plants. To evaluate the effect of some physical seed priming materials (ultrasonic, gamma, beta and laser irradiation, magnetic field and hydro-priming) on seed germination and growth of marigold a laboratory experiment was conducted at Islamic Azad University of Tabriz branch, using completely randomized design, with three replicates. The results revealed that the highest seed germination percent took place in seeds treated with “magnetic field” for 5 min. and lowest in those treated by beta irradiation and “magnetic field” for 15 min. Mean comparions indicated that the highest root length belonged to seeds treated by ultrasonic and laser irradiation for 10 min. and lowest from seeds primed by beta irradiation, magnetic field for 15 min., laser irradiation for 5 min. and control. Higest seedling vigor index was obtained when seeds primed by laser irradiation for 10 min. It was also observed that the lowest fruit yield produced by seeds treated with beta irradiation. It may be concluded that tomato producers could improve seed germination percent by priming the seed with magnetic field for 15 minutes.

Irradiance stress and plant spacing effect on growth, biomass and quality of wild marigold (Tagetes minuta L.) – an industrial crop in western Himalaya

A study was carried out over 2 years (2009 and 2010) at the CSIR–Institute of Himalayan Bioresource Technology, Palampur, India, to investigate the effect of irradiance stress and plant spacing on growth, biomass yield, essential oil content and composition in wild marigold (Tagetes minuta L.). Four shade levels (0%, 25%, 50% and 75%) and three plant spacing (45 × 30, 45 × 45 and 60 × 45 cm) were tested as per split plot design. Heavy shading (50% and 75%) strongly reduced the total essential oil content in fresh leaves and flowers. The essential oil content of leaves, flowers and the total oil increased up to the 25% shade level and declined thereafter, with a decrease in irradiance level. Ocimene and dihydrotagetones concentration in leaf oil decreased with decrease in irradiance level; however, tagetone and ocimenone showed the reverse trend. In flower oil, ocimene decreased with an increase in shade levels. Fresh leaf, stem, flower, leaf + flower biomass, and total biomass was significantly higher in the 45 × 30 cm spacing level. Essential oil content in flowers of T. minuta grown in 25% shade at 45 × 45 and 45 × 30 cm spacing recorded significantly higher essential oil content than other treatments.

Influence of vermicompost application in potting media on growth and flowering of marigold crop

This paper reports the influence of vermicomposts prepared from cow dung and house hold waste on the growth and flowering of marigold crop. A total of seven potting media were prepared containing soil, cow dung vermicompost and cow dung + house hold waste vermicompost. The fertility status of soil and vermicomposts was quantified. In these media, growth and flowering of marigold plant seedlings was studied for 60 days. The results showed that the vermicomposting process converted the cow dung and household waste into a highly stabilized product having C:N ratio <20.0. The NPK content of vermicomposts was higher than soil. The plant grown in vermicompost-containing potting media had 2.3 times more plant height than control. Results showed that the addition of vermicompost, in appropriate quantities, to potting media has significantly positive effects on growth and flowering of marigold seedlings including plant biomass, plant height, number of buds and flowers. It was concluded that addition of vermicompost, in appropriate quantities, to potting media has synergistic effects on growth and yield of marigold.

Effects of Growing Conditions of Marigold in Ilam District, Nepal

Different growing conditions with temperature and sunlight variation could vary in flower growth and quality of marigold. Plant growth and flowering characteristics are compared in three different conditions viz. plastic house, shade house and open field. Three varieties of marigold viz. Marvel Yellow, Marvel Orange and Marvel Garland with similar cultural practices were grown and observed. Each variety with 6 replications was grown in three different growing conditions. Plant height, leaves formation, length of leaves, number of days to flower, number of flowers per plant and post harvest analysis were recorded. Plant growth characteristics followed by flowering behavior were found significantly better in plants grown under plastic house. During post harvest experiment Marvel Garland variety grown under plastic house with wet post harvest treatment was found significantly better compared to other conditions.

Response of pinching and foliar application of gibberellic acid on growth and flower yield in summer African marigold

A field experiment was conducted at Main Garden, Department of Horticulture, Dr. P. D. K. V., Akola with the objective to study the effect of pinching and foliar application of gibberellic acid on growth and yield of African marigold. Treatments comprised four levels of pinching i. e. no pinching, pinching at 15 DAT, pinching at 22 DAT and pinching at 30 DAT and four levels of gibberellic acid i. e. 100 ppm, 200 ppm, 300 ppm and control during summer seasons of the years 2010–11 and 2011–12. Among the pinching treatments, pinching at 15 DAT was found to be the best for improving vegetative growth parameters and flower yield. In respect of foliar application of gibberellic acid, gibberellic acid 300 ppm was recorded significantly better for increasing the vegetative growth and flower yield.

Growth and Flowering before and after Storage of African Marigold and Salvia Seedlings Stored under Different Light Conditions

This study was conducted to investigate the growth and flowering of African marigold (Tagetes erecta L.) and salvia (Salvia splendens F. Sello ex Ruem & Schult.) seedlings before and after storage under fluorescent lamps and green LED radiation conditions with different light intensities during storage. The both seedlings were kept under a storage room controlled at <TEX>$8^{\circ}C$</TEX> air temperature and <TEX>$40{\pm}10%$</TEX> relative humidity conditions. Light intensities were maintained at 15 and <TEX>$30{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$</TEX> during storage. In lighting treatments, dry weight of African marigold at 28 days after storage was not significantly different, and decreased approximately 29% compared to pre-storage under dark treatment. There was no significant difference in the leaf area of salvia seedlings stored under dark condition compared to before storage, but the leaf area under green light radiation with higher light intensity (treatment GH) was two times greater than before storage. The survival rate after transplanting of African marigold stored under dark condition was 10%, and days to flowering increased compared to those stored under fluorescent and green light with higher light intensity (treatment FLH, GH). Comparing to before storage, growth and flowering of the both seedlings after storage were significantly promoted by the light exposure during storage. The present experimental results show that the light intensity should be decided to maintain minimum growth during lighting storage and storage quality of the seedlings such as flowering promotion and extended blooming period after lighting treatment during storage period from the above results.

Effect of Plant Growth Regulators on Growth and Yield of African Marigold (Tagetes erecta Linn.)

A field experiment was conducted at Experimental Farm, Department of Horticulture, S. K. N. College of Agriculture, Jobner, SKRAU, Bikaner (Rajasthan) to find out the effect of plant growth regulators on growth and yield of marigold. Treatments consist of two levels of spray i.e. single spray (S1) and double spray (S2) and four levels of each Plant Growth Regulator viz., GA3 (GA50, GA100, GA150 and GA200 ppm) and NAA (N50, N100, N150 and N200 ppm) in African marigold (Tagetes erecta Linn.) cv. Pusa Narangi Gainda. The results revealed that single spray of GA3 @ 150 ppm recorded significantly higher plant height (83.30 cm), leaf area (1188.58 cm2), number of flowers per plant (78.49), average weight of flower (4.85 g) and yield of flowers per plant (365.23 g) as well as per hectare (132.27 q/ha). Application of NAA 150 ppm as a single foliar spray significantly increased plant height (72.22 cm), chlorophyll content in leaves (2.89 mg g-1), duration of flowering (69.14 days), yield of flowers per plant (360.09 g) as well as per hectare (13.04 tonnes/ha).

EFFECT OF COTTONSEED MEAL WITH OR WITHOUT SOAPSTOCK, CANOLA MEAL, OR UREA ON SOIL FERTILITY AND GROWTH OF MARIGOLD AND REDBUD

The effects of incorporating or topdressing with cottonseed (Gossypium hirsutum L.) meal with or without soapstock, canola (Brassica rapa L.) meal, urea, or no amendment (control) were investigated using plants of marigold (Tagetes erecta L. ‘Inca II Gold’ or ‘Inca II Yellow’) and redbud (Cercis canadensis L.) in a Norge loam (fine-silty, mixed, thermic Udic Paleustolls) at Stillwater, OK in 2008 and 2009. Fertilizers were applied in May at 4.9 g•m−2 N based on soil test results prior to the study and nitrogen (N) recommendations for turfgrass. Soil nitrate-nitrogen (NO3-N) and phosphorus (P) increased from 2008 to 2009 in marigold plots into which cottonseed meal with soapstock was incorporated, and boron (B) increased in all marigold plots regardless of treatment. In 2009, marigolds grown in plots into which cottonseed meal was incorporated were taller than plants in other treatments except the untreated control. Marigolds in plots in which cottonseed meal was topdressed, cottonseed meal with soapstock was incorporated, or urea was topdressed grew less in height than plants in plots with cottonseed meal incorporated or control plots. Shoot dry weights of marigold plants in plots topdressed with cottonseed meal with or without soapstock, urea, or control plots were lower than those of plants in other treatments. Visual ratings of marigold plants receiving a topdress of urea or no treatment were lower than visual ratings of plants in any other treatment in July, but similar in August to those of marigold plants in plots in which cottonseed meal was topdressed. Some differences within fertilizer treatments occurred between 2008 and 2009 in redbud soil concentration of NO3-N, calcium (Ca), magnesium (Mg), sulfate-sulfur (SO4-S), iron (Fe), B, and copper (Cu). Leaf P concentration differed among fertilizer treatments in 2009. Leaf and total dry weight of redbuds grown in soil incorporated with urea was greater than that of plants in any other treatment. Results indicate that cottonseed and canola meals provide N and other nutrients for growth of landscape plants. Soil incorporated cottonseed meal encouraged more growth of marigold than soil incorporated urea but less growth of redbud.

Storage Time and Amendments Affect Pine Tree Substrate Properties and Marigold Growth

Pine tree substrate (PTS) is a relatively new alternative to the commonly used pine bark and peat-based substrates for container crop production. Physical and chemical properties of freshly manufactured PTS have been studied; however, this new substrate will sometimes be manufactured and stored for later use by growers. The objective of this research was to determine how chemical and physical properties of PTS were affected by storage duration with or without amendments of limestone or peatmoss. We also studied how the growth of marigold was influenced by PTS storage time and by lime and peat amendments. Substrate properties studied were pH, cation exchange capacity (CEC), electrical conductivity (EC), carbon-to-nitrogen ratio (C:N), bulk density (BD), and particle size distribution. Pine tree substrate was manufactured by hammermilling chips of ≈15-year-old loblolly pine trees (Pinus taeda L.) through two screen sizes, 4.76 mm (PTS) and 15.9 mm [amended with peat (PTSP)]. Pine tree substrate and PTSP were amended with lime at five rates and a peat–perlite mix (PL) served as a control treatment. Substrates were prepared, placed in plastic storage bags, and stored on shelves in an open shed in Blacksburg, VA. Substrates were subsampled at 1, 42, 84, 168, 270, and 365 days after storage. At each subsampling day, twelve 1-L containers were filled with a subsample of each treatment. Six of the 12 were left fallow and six were planted with 14-day-old marigold (Tagetes erecta L. ‘Inca Gold’) seedlings. Substrate was also collected for analysis of CEC, C:N, BD, and particle size distribution. The pH of non-limed PTS decreased during storage, and at least 1 kg·m−3 lime was needed to maintain PTS pH 5.4 or greater over the 365-day storage period (Day 1 pH = 5.8) and 2 to 4 kg·m−3 was needed to maintain PTSP pH 5.4 or greater for 365 days (Day 1 pH = 5.2). EC measurements were highest at Day 1 (1.02 to 1.21 dS·m−1) in all treatments and decreased by Day 42. Cation exchange capacity decreased over time in non-limed PTS and PTSP. Carbon-to-nitrogen ratio and BD remained the same over time for all treatments. There were minor changes in particle size distribution for limed PTS. Marigold growth in all limed PTS and PTSP treatments was equal to or greater than in PL, except at Day 1; the lower growth in PTS and PTSP at Day 1 compared with PL suggests that freshly manufactured PTS may contain a phytotoxic substance that was not present in PTS by Day 42. Pine tree substrate and PTSP are relatively stable when stored as described previously, except for a pH decrease that can be prevented with additions of lime before storage.

Horticultural and Floricultural Applications of Urban Wastes Originated Fertilizers

Different origin composts and a digestate from a biogas plant and their respective alkali soluble (SBO) and insoluble (IOR) fractions have been tested as organic fertilizers in growth media. The materials have been characterized by determination of pH, salinity, C, N, P, and K content. A preliminary evaluation of the possible phytoxicity has been performed by determination of the germination indexes of cress (Lepidium sativum), white mustard (Sinapsis alba) and radish (Raphanus sativus). Most of the materials did not promote the germination of the seeds. Notwithstanding these negative results, the materials were also used as partial peat substitute in a commercial substrate to test the growth of marigold (Tagetes patula), radish (Raphanus sativus), and spinach (Spinacia oleracea). The dimension and dry weight of the plants grown on the substrate mixed with the composts, the digestate or the SBOs were similar to those observed on the substrate. Moreover, most of the SOBs provoked the increase of the dry weight of the roots of the radishes, therefore an increase of the quality. The insoluble fractions (IOR) from the composts allowed a growth of the plants similar to that obtained with a commercial substrate. In contrast, the IOR obtained from the digestate was phytotoxic.

Supplementary Blue and Red Radiation at Sunrise and Sunset Influences Growth of Ageratum, African Marigold, and Salvia Plants

BACKGROUND: Light-emitting diodes (LEDs) with lower electric cost and the specific wavelength have been considering as a novel light source for plant production in greenhouse conditions as well as in a closed culture system. Supplementary lighting for day-length extension was considered as light intensity, light quality, and/or photoperiod control on plant growth and development. Effects of supplementary blue or red LED radiation with lower light intensity on growth of Ageratum (Ageratum houstonianum Mill., cv. Blue Field), African marigold (Tagetes erecta L., cv. Orange Boy), and Salvia (Salvia splendens F. Sello ex Ruem & Schult., cv. Red Vista) were discussed during sunrise and sunset twilight in the experiment. METHODS AND RESULTS: Supplementary lighting by blue and red LEDs for 30 (Treatment B30; R30) or 60 (Treatment B60; R60) min. per day were established in greenhouse conditions. Photosynthetic photon flux for supplementary radiation was kept at 15 μmol m-2 s-1 on the culture bed. Natural condition without supplementary light was considered as a control. The highest shoot and root dry weights were shown in African marigold exposed by red light for 60 min. per day. Supplementary blue and red lighting regardless of the radiation time significantly stimulated development of lateral branches in African marigold. Stem growth in Ageratum and Salvia seedlings was significantly promoted by red radiation as well as natural light. CONCLUSIONS: Extending of the radiation time at sunrise and sunset twilight using LEDs stimulated reproductive growth of flowering plant species. Different characteristics on growth under supplementary blue or red lighting conditions were also observed in the seedlings during supplementary radiation.

Growth, Cadmium Accumulation and Physiology of Marigold ( Tagetes erecta L.) as Affected by Arbuscular Mycorrhizal Fungi

A pot experiment was carried out to study the effects of three arbuscular mycorrhizal fungi (AMF), including Glomus intraradices, Glomus constrictum and Glomus mosseae, on the growth, root colonization and Cd accumulation of marigold (Tagetes erecta L.) at Cd addition levels of 0, 5 and 50 mg kg −1 in soil. The physiological characteristics, such as chlorophyll content, soluble sugar content, soluble protein content and antioxidant enzyme activity, of Tagetes erecta L. were also investigated. The symbiotic relationship between the marigold plant and arbuscular mycorrhizal fungi was well established under Cd stress. The symbiotic relationship was reflected by the better physiobiochemical parameters of the marigold plants inoculated with the three AMF isolates where the colonization rates in the roots were between 34.3% and 88.8%. Compared with the non-inoculated marigold plants, the shoot and root biomass of the inoculated marigold plants increased by 15.2%-47.5% and 47.8%−130.1%, respectively, and the Cd concentration and accumulation decreased. The chlorophyll and soluble sugar contents in the mycorrhizal marigold plants increased with Cd addition, indicating that AMF inoculation helped the marigold plants to grow by resisting Cd stress. The antioxidant enzymes reacted differently with the three AMF under Cd stress. For plants inoculated with G. constrictum and G. mosseae, the activities of Superoxide dismutase (SOD) and catalase (CAT) increased with increasing Cd addition, but peroxidase (POD) activity decreased with increasing Cd addition. For plants inoculated with G. intraradices, three of the antioxidant enzyme activities were significantly decreased at high levels of Cd addition. Overall, the activities of the three antioxidant enzymes in the plants inoculated with AMF were higher than those of the plants without AMF inoculation under Cd stress. Our results support the view that antioxidant enzymes have a great influence on the biomass of plants, and AMF can improve the capability of reactive oxygen species (ROS) scavenging and reduce Cd concentration in plants to alleviate Tagetes erecta L. from Cd stress.

Fertilization enhances growth, yield, and xanthophyll contents of marigold

The effects of various NPK levels on growth, flowering, and xanthophyll contents of African marigold (Tagetes erecta, 'Double Eagle') and French marigold (Tagetes patula, 'Yellow') were investigated. Plant height, number of branches plant^{-1}, leaf area (cm^2), total chlorophyll contents (mg g^{-1}), number of flowers plant^{-1}, flower diameter, flower quality, fresh and dry weight of a flower, total flower weight plant^{-1}, blooming period, and days to flowering were maximum with 15:10:10 g m^{-2} NPK application. However, leaf nitrogen, phosphorus, and potassium contents reached the highest values with 15:20:10, 5:20:10, and 10:20:10 g m^{-2} NPK application, respectively. Xanthophyll contents were higher in plants fertilized with 15:20:10 g m^{-2} NPK application. Results suggested that NPK fertilization enhanced growth and improved yield, quality, and xanthophyll contents of marigold.

EVALUATION OF THE USE OF SYNTHETIC RED SOIL AGGREGATES (SRA) AND ZEOLITE AS SUBSTRATE FOR ORNAMENTAL PLANT PRODUCTION

This research was undertaken to evaluate the influence of zeolite and synthetic aggregates (SRA) produced with acidic red soil and paper waste, on the growth of French marigold (Tagetes patula), which is a popular ornamental plant in Japan. Five different media were studied: SRA only, SRA:Zeolite 3:1, SRA:zeolite 1:1, SRA: zeolite 1:3 and zeolite only. Mixing SRA with zeolite improved the physical and chemical properties of the media such as particle size distribution, bulk density, total porosity, water holding capacity, and pH compared to zeolite. SRA and zeolite at 1:1 gave the best maximum growth parameters of French marigold. Zeolite based mixtures increased the nitrogen (N), potassium (K), magnesium (Mg), and calcium (Ca) concentrations in plant tissues compared to SRA medium. Addition of zeolite led to reduce K leaching from the substrate compared to SRA. SRA and Zeolite at 1:1 can be recommended as a better substrate for French marigold cultivation.

Alleviation of drought stress of marigold ( Tagetes erecta) plants by using arbuscular mycorrhizal fungi

The effect of an arbuscular mycorrhizal fungus “AMF” ( Glomus constrictum Trappe) on growth, pigments, and phosphorous content of marigold ( Tagetes erecta) plant grown under different levels of drought stress was investigated. The applied drought stress levels reduced growth vigor (i.e. plant height, shoot dry weight, flower diameter as well as its fresh and dry weights) of mycorrhizal and non-mycorrhizal plant as compared to control plant (non-drought stressed plant). The presence of mycorrhizal fungus, however, stimulated all growth parameters of the treated plant comparing to non-mycorrhizal treated plant. The photosynthetic pigments (carotene in flowers and chlorophylls a and b in leaves) were also stimulated by the mycorrhizal fungi of well-watered as well as of water-stressed plants. The total pigments of mycorrhizal plants grown under well-watered conditions were higher than those of non-mycorrhizal ones by 60%. In most cases, drought-stressed mycorrhizal plants were significantly better than those of the non-mycorrhizal plants. So, the overall results suggest that mycorrhizal fungal colonization affects host plant positively on growth, pigments, and phosphorous content, flower quality and thereby alleviates the stress imposed by water with holding.

Growth and yield response of marigold to potting media containing vermicompost produced from different wastes

Investigations were made to assay the influence of vermicomposts, prepared from (i) cow dung (CD) and (ii) sugar mill wastewater treatment plant sludge spiked with horse dung, on the growth and productivity of marigold plants in pot culture experiments. The soil was used as potting media, and vermicomposts were amended with it in 10, 20, 30 and 40% ratio. A total of nine different potting media were prepared. The fertility status of soil and vermicomposts was quantified. There were significant differences in the fertilizer quality of soil and both the vermicomposts. Maximum numbers of flowers was produced in the potting media containing 30% of CD vermicompost and minimum was reported in control (soil without amendments). The diameter of biggest flower was reported in the potting media containing 40% of sugar mill wastewater treatment plant sludge vermicompost. Results showed that the addition of vermicompost, in appropriate quantities, to potting media has synergistic effects on growth and flowering of plants including number of buds, number of flowers, plant shoot biomass, root biomass, plant height and diameter of flowers.

Methods of Constructing a Pine Tree Substrate from Various Wood Particle Sizes, Organic Amendments, and Sand for Desired Physical Properties and Plant Growth

The use of freshly harvested and processed pine trees as a container substrate for greenhouse and nursery crop production is a relatively new concept, and fundamental knowledge of the construction of a pine tree substrate (PTS) for optimal physical properties is insufficient. Therefore, this research was conducted to determine the influence of mixing PTSs produced with different wood particle sizes and adding other amendments to PTS on substrate physical properties and plant growth compared with traditional substrates. Coarse pine wood chips produced from 15-year-old loblolly pine trees (Pinus taeda L.) were ground in a hammermill fitted with either a 4.76-mm screen or with no screen (PTS-NS) allowing a fine and a coarse particle PTS to be produced. Increasing proportions of the finer (4.76-mm) PTS to the coarser PTS (PTS-NS) resulted in increased container capacity (CC) and shoot growth of ‘Inca Gold’ marigold (Tagetes erecta L.). In another study, PTSs were manufactured in a hammermill fitted with different screen sizes: 4.76, 6.35, 9.54, or 15.8 mm as well as PTS-NS. After being hammermilled, each of the five PTSs was then amended (by mixing) with 10% sand (PTS-S), 25% peatmoss (PTS-PM), or left unamended. Pine tree substrates were also produced by adding 25% aged pine bark (PB) to pine wood chips before being ground in a hammermill with each of the five screen sizes mentioned (PTS-HPB). These five substrates were used unamended as well as amended with 10% sand after grinding (PTS-HPBS). Control treatments included peat-lite (PL) and 100% aged PB for a total of 27 substrates evaluated in this study. Container capacity and marigold growth increased as screen size decreased and with the additions of peatmoss (PTS-PM) or hammering with PB (PTS-HPB) to PTS. Container capacity for all substrates amended with peatmoss or PB was within the recommended range of 45% to 65% for container substrates, but only with the more finely ground PTS-4.76-mm resulted in marigold growth comparable to PL and PB. However, when the PTS-NS was amended by mixing in 25% peat or hammering with 25% PB, growth of marigold was equal to plants grown in PL or PB. In a third study, hammering PTS-NS with 25% PB followed by the addition of 10% sand increased dry weight of both azalea (Rhododendron ×hybrida ‘Girard Pleasant White’) and spirea (Spiraea nipponica Maxim. ‘Snowmound’) resulting in growth equal to plants grown in 100% PB. This work shows that amending coarsely ground PTS with finer particle PTS or with other materials (peatmoss, aged PB, or sand) can result in a substrate with comparable physical properties such as CC and plant growth compared with 100% PL or PB.

Effect of Integrated Nutrient Management on Growth, Flowering Behaviour and Yield of African Marigold (Tagetes erecta L.) Cv. African Giant Double Orange

A field experiment was carried out to study the effect of integrated nutrient management on growth, flowering behaviour and yield of marigold (Tagetes erecta L.) at the main experiment station, Narendra Deva University of Agriculture and Technology, Narendra Nagar (Kumarganj), Faizabad, during 2004 and 2005 in Randomized Block Design. There were thirteen treatments involving two biofertilizers, viz., Azotobacter and phosphorus solubilizing bacteria (PSB) and two levels of nitrogen and phosphorus, viz., (50% and 100%), farm yard manure (FYM) and control (recommended dose of NPK., i.e., 200:100:100 kg/ha). One month old seedlings were transplanted at a spacing of 40 x 30 cm. Results revealed that combined application of Azotobacter and PSB with FYM and 50% recommended dose of nitrogen and phosphorus significantly improved growth, flowering behavior and yield during both years (2004 and 2005). Application of Azotobacter + PSB + FYM @ 30 ha-1 + nitrogen @ 100 ha-1 and phosphorus @ 50 kg/ha was found to be best for growth, flowering behaviour and yield of cv. African Giant Double Orange.