Spray Chrysanthemum Research Articles

EFFECT OF POSTHARVEST TREATMENTS ON THE VASE LIFE AND QUALITY OF CUT CHRYSANTHEMUM

An investigation was carried out to study the effect of preservative solutions on vase life, fresh weight, flower diameter and chlorophyll content of spray chrysanthemum (Dendranthema morifolium) cvs Clarence and Streamer. Distilled water (control), sucrose 2%+ cobalt chloride 50 ppm or + 8-HQS 500 ppm or + sodium benzoate 50 ppm or + ascorbic acid 50 ppm were used in the experiment. Sucrose 2% + 8-HQS 500 ppm and sucrose 2% + cobalt chloride 50 ppm resulted the longest vase life in the two cultivars. The highest fresh weight were obtained with sucrose 2% + cobalt chloride and sucrose 2% + 8-HQS 500 ppm respectively. The greatest flower diameter of cv. Clarence were obtained with sucrose 2% + cobalt chloride treatments while the greatest flower diameter of cv. Streamer were obtained with sucrose 2% + cobalt chloride and sucrose 2%+ 8-HQS 500 ppm respectively. Control treatment gave the lowest content of chlorophyll in cv. Clarence, but cv. Streamer was not affected.

アプリコットおよび覆輪花系スプレーギクの花色に及ぼす作期と栽培温度の影響

アプリコット色花系および覆輪花スプレーギクにおける花色が作期または栽培温度により変化する様相を明らかにするため，各作期または各温度下で開花した花色を測定し，舌状花のアントシアニンおよびカロテノイド量を測定した．アプリコット色花系品種では6/30作期または30℃処理区で黄色味の花色を呈し，a*値が減少し，b*およびh値が増加した．覆輪花品種は，高温下で赤色部位が淡色化または消失し，作期または温度間で覆輪割合が変動した．覆輪の発現には①高温下で赤色部位が減退することで花弁先端に白色部位が出現する品種②涼温下で赤色部位が増加することで明瞭な覆輪が出現する品種の2つのパターンが見られた．いずれの品種においても赤色花キクの主要花色素であるCy3-6''-MMGおよびCy3-3'',6''-DMGが主要アントシアニンとしてHPLCにより検出された．また，多くの品種ではカロテノイド量は温度による影響は少なく，2つの主要アントシアニンの増減によってアプリコット色花系品種の花色および覆輪花系品種の覆輪割合の変動が生じるものと考えられた．

Developing a Nitrogen Application Curve for Spray Chrysanthemums grown in Hydroponic System and its Practical Use in NFT System.

Spray chrysanthemums 'Talk' (autumn-flowering type) were grown in a hydroponic system with N supply maintained at high levels. The plant growth, N uptake, and cut flower quality were subsequently evaluated in relation to 3 different planting dates. Fresh plant weight and N uptake increased throughout the growing period but at a decreasing rate towards harvest. Shoot lengths and weights ranged from 92a112cm and 85a97g, respectively. Comparison revealed that the cut flowers were longer and heavier than a standard of best grade in the market. Based on N uptake and plant growth, a down-regulated N application curve (NAC) was developed for producing economically marketable cut flowers. To produce a plant having two shoots of 70g, which is probably suitable for the market, 954a1142mg N fertilizer was computed to be appropriate. Using the NAC, spray chrysanthemum 'Talk' was grown in Nutrient Film Technique (NFT) system. Under 0.8 and 1.0 strengths of NAC, the mean shoot lengths and weights wereg94.2cm and g65.6g, respectively, yielding more than 64% of best grade cut flowers. At NAC 0.8 and 1.0 strengths, 90a100% N, 90a98% P and K of applied amounts were consumed, thus confirming an efficient uptake of these nutrients. Consequently, the nutrient application based on 0.8a1.0 strengths of NAC could produce economically marketable autumn-flowering spray chrysanthemums.

Mineral Uptake as Influenced by Growing Seasons and Developmental Stages in Spray Chrysanthemums Grown under a Hydroponic System.

Characteristics of mineral uptake in spray chrysanthemums grown under a hydroponic system were investigated in relation to growing seasons and developmental stages. The amounts of N, P, K, Ca, and Mg, taken up per plant, differed markedly over the growing seasons and between 'Sei Aloha' and 'Talk'. However, the ratios of P, K, Ca, and Mg to N uptake were similar over both the growing seasons and cultivars. The ratios obtained from the nutrient solution analyses were P/N 13.3±0.4%, K/N 102.6±3.4%, Ca/N 29.6±0.7% and Mg/N 10.0±0.4%. The ratios corresponded to those estimated via plant tissue analyses. Uptake of 4.3-5.2mg N fertilizer led to an increase of 1g in fresh weight. The rate of N uptake steadily rose after planting until flower buds became visible. The upward trend continued during bud development but decreased rapidly towards harvest. The ratios of P/N and K/N decreased from 16.2% and 134.2% to 8.4% and 69.5%, respectively, from the vegetative growth to the flowering stages. The ratios of Ca/N and Mg/N varied slightly.

ＮＦＴ栽培における培養液量がスプレイギクの養分吸収と切り花品質に及ぼす影響

Two cultivars of spray chrysanthemum (Dendranthema grandiflorum), ‘Sei Aloha’ (summer-to-autumn flowering cultivar) and ‘Pinky’ (autumn flowering cultivar), were grown in NFT system and the effects of varying nutrient solution volumes (0.25, 0.50, 0.75, 1.00, 2.00 L plant-1) on mineral uptake and cut flower quality were investigated. The N, P and K uptake remained unaffected with the varying nutrient solution volumes. Nutrient solution volumes of <0.75 L plant-1 resulted into considerable reduction in the shoot length and shoot weight, thus giving rise to poor cut flower quality. Root growth inhibition was observed under 0.25 L plant-1. Reduction in plant growth under smaller nutrient solution volumes occurred possibly via unstable root environment, large fluctuation in EC and pH, and excess accumulation of root exudates in the recirculated nutrient solution. Charcoal addition did not alleviate the reduction in plant growth under 0.25 L plant-1. Also, weekly renewal of nutrient solution with 0.25 L plant-1 resulted in less plant growth compared to 1.00 L plant-1 without renewal.

Manutenção da qualidade e aumento da longevidade floral de crisântemo cv. White polaris

0 objetivo do trabalho foi determinar o melhor tratamento pós-colheita para manutenção floral e aumento da longevidade de crisântemo de maço do tipo pompom (Dendranthema grandiflorum (Ramat.) S. Kitamura) cv. White Polaris. Estabeleceu-se como ponto de colheita o momento em que as hastes apresentavam três inflorescências apicais com as pétalas externas em ângulo de 45° em relação à horizontal. Durante o ensaio em laboratório, as hastes, colhidas em estufa de produção comercial, após totalmente imersas em água de torneira, à sombra, durante três horas, foram cortadas sob água na base do caule entre 50 e 60 cm. As hastes foram distribuídas nos diferentes tratamentos de "pulsing" durante 24 horas, com luz contínua de 1.500 lux, 60 a 90% de umidade relativa do ar e temperatura ambiente de 25 ± 2°C. No primeiro experimento, testou-se a eficiência de 8-hidroxiquinolina (8-HQ) e tiabendazole (TBZ) como germicidas de manutenção da qualidade na solução de "pulsing"; testaram-se, também, dois reguladores de crescimento, a saber: ácido giberélico (GA3), 6-benzilaminopurina (6-BA) ou a mistura dos dois, com o objetivo de preservar a cor e a turgidez da folhagem. Os melhores resultados foram com 8-HQ (0,69 mol/m³) e GA3 (0,058 mo1/m³). No segundo experimento, avaliaram-se os seguintes inibidores de etileno: tiossulfato de prata (STS), nitrato de prata (AgNO3) e cloreto de cobalto (COC1(2)). A melhor resposta foi obtida com AgNO3 (2,9 e 4,4 mo1/m³).

Determinação do ponto de colheita e indução à abertura floral do crisântemo cultivar White Polaris em diferentes concentrações de sacarose

Realizou-se pesquisa objetivando determinar o melhor entre quatro pontos de colheita da haste floral de crisântemos de maço do tipo pompom cv. White Polaris a concentração mais adequada de sacarose para tratamento de "pulsing" dessas hastes: estas foram colhidas em estufa de produção comercial, nos pontos preestabelecidos e transportadas para laboratório, onde foram totalmente imersas em água de torneira, à sombra, durante três horas. Selecionaram-se as hastes pela uniformidade do seu desenvolvimento e cortaram-nas sob água na base do caule, entre 50 e 60 cm, e identificadas, o que permitiu avaliar as mudanças morfológicas associadas às inflorescências individuais. As hastes foram distribuídas e mantidas nos diferentes tratamentos de "pulsing" durante 24 horas, à luz branca contínua de 1.500 lux, 60 a 90% de umidade relativa do ar e temperatura ambiente de 25 ± 2°C. Após o tratamento de "pulsing", as hastes foram transferidas para água destilada, permanecendo por 10 horas sob luz branca contínua, nas mesmas condições de laboratório citadas. A vida floral em vaso começou a ser avaliada na instalação do experimento, após o tratamento de "pulsing", e terminou quando as folhas e pétalas perderam a turgescência e o valor decorativo. As hastes colhidas em estádio de botão (25 e 50% de abertura das inflorescências apicais) não alcançaram o ponto de abertura adequado em nenhuma das seis concentrações de sacarose (0 a 146,07 mol/m³); as concentrações de 116,9 146,1 mol/m³, porém, estimularam, em geral, a abertura de botões. Os pontos de colheita 1 e 2 (100 e 75% de abertura das inflorescências apicais respectivamente) apresentaram bons resultados em todas as concentrações de sacarose.

Effects of irrigation frequency on root formation and shoot growth of spray chrysanthemum cuttings in small jute plugs

Small plugs of organic, fibrous material (jute) were used as a propagation medium for spray chrysanthemum cuttings instead of the more conventional, pre-fertilized compressed peat blocks. A complete nutrient solution was supplied to the jute plugs by means of ebb-and-flow irrigation. Four different irrigation frequencies (IF) were compared, i.e. 96, 24, 6 and 1 day −1. During the root initiation stage, the irrigation treatments had little effect on the cuttings. Once a new root system had been generated, a strong positive correlation between IF and growth was observed. Shoots of rapidly growing cuttings contained relatively high levels of nutrients and low non-structural carbohydrate levels and had a high turgor. These results demonstrate that during propagation from cuttings, growth may be limited by the availability of water and minerals. In the case of chrysanthemum cuttings in small jute plugs, factors limiting growth can be overcome by frequent irrigation with a complete nutrient solution.

Influence of Leaf Nitrogen on Leafminer Damage and Yield of Spray Chrysanthemum

Abstract Damage by leafminer [Liriomyza trifolii (Burgess)], increased linearly as leaf nitrogen increased from 2.2% to 4.0% in spring and fall plantings of Chrysanthemum x morifolium Ramat. ‘Manatee Yellow Iceberg’. The number of marketable stems was related quadratically to leaf nitrogen with maximum yields estimated to occur at 3.6% at harvest.

Response of Mites and Leafminers to Trickle Irrigation Rates in Spray Chrysanthemum Production1

Abstract The numbers of twospotted spider mites (Tetranychus urticae Koch) per unit of leaf area on ‘Manatee Yellow Iceberg’ chrysanthemum (Chrysanthemum X morifolium Ramat.) grown with 13.6, 20.3, 27.1, 33.9, or 40.7 cm of water during the crop cycle were inversely related to amounts of water provided on both of 2 sampling dates. The numbers of mites per leaf were inversely related to amounts of water provided on the first of the 2 sampling dates. There was no significant response of leafmine densities with various amounts of water provided.

ROOT ZONE WARMING OF SPRAY CHRYSANTHEMUMS IN HYDROPONICS

ROOT ZONE WARMING OF SPRAY CHRYSANTHEMUMS IN HYDROPONICS

Spray Chrysanthemum Production with Controlled-release Fertilizer and Trickle Irrigation1

Abstract Various rates, types, and formulations of controlled-release fertilizers were evaluated as potential components in a trickle irrigation production system for spray chrysanthemums (Chrysanthemum morifolium Ramat.). Optimum rates of total-N, with 34 kg N/ha as soluble 6-2.6-5 (N-P-K) and the remainder as 14-6.1-11.6 Osmocote, were estimated to be from 489-501 kg per planted hectare in 2 tests. Other formulations or ratios of Osmocote and urea formaldehyde fertilizers at similar rates did not improve production or were not comparable to Osmocote 14-6.1-11.6 or to the commercial practice of weekly overhead liquid fertilization. A water savings of 70-80% was estimated with the controlled-release fertilizer-trickle irrigation system compared to overhead irrigation, while yields (marketable stems and height) were similar to those produced with overhead-liquid fertilization practices.

Crop Response in a Greenhouse Environmentally Controlled with Air Drawn from a Coal Mine1

Abstract The environment created by ventilating a greenhouse with mine-air was suitable for the production of high quality spray chrysanthemums (Chrysanthemum morifolium Ramat.) and snapdragons (Antirrhinum majus L.) from mid-February through November without any additional energy requirement. The environment created in the greenhouse from December to February was extremely humid and favored botrytis development and physiological problems which reduced crop quality.

Some effects of copper and boron deficiencies on the growth and flowering of chrysanthemum morifolium (cv. hurricane)

AbstractThe effects of copper and boron deficiencies on spray chrysanthemums (cv. Hurricane) have been studied in a peat‐sand substrate. Severe copper deficiency prevented bud initiation and development; the lateral shoots, if present, elongated and produced numerous bracts and leaves. In these respects the deficiency simulated the effects of continuous long day treatment, but differed by causing collapse and death of the lower leaves. Less severe deficiency of copper greatly delayed flowering, reduced the size of the sprays and the numbers of flowers per spray, and rendered much of the crop unsaleable. Boron deficiency caused some quilling of the petals but had relatively little effect on other aspects of growth and flowering in these experiments. Where copper deficiency was not severe, however, omission of boron and copper together affected flowering more than did either deficiency alone. Possible explanations of this interaction are discussed. Analytical data for boron and copper in the foliage are tabulated.

Some responses of Chrysanthemum morifolium (cv.“hurricane”), grown as a year‐round crop in a peat‐sand substrate, to micronutrients and liming

AbstractThe effects of a fritted micronutrient mixture on the growth and flowering of spray chrysanthemums (cv.“Hurricane”) were studied in relation to pH in a peatsand substrate (3:1 by volume). The treatments consisted of three rates of application of a fritted micronutrient mixture (0, 200, 500 g/m3) in factorial combination with four rates of liming (average pH values 4.2, 5.0, 6.3 and 7.1). Five successive crops were grown under conditions, including controlled day‐length, used commercially for year‐round chrysanthemum production.Bud initiation and development were greatly delayed in the absence of micro‐nutrients, particularly at high pH, and some plants failed to flower. The proportion of marketable sprays was decreased by omission of micronutrients (P&lt;0.001) and by liming (P&lt;0.001), and those that were saleable were reduced in size. Omission of micronutrients decreased the numbers of flowers per spray (P&lt;0.001). Plants grown without added micronutrients developed more leaves and bracts on their lateral shoots (P&lt;0.001), particularly at high pH (6.3–7.1); the interaction between lime and micronutrients was significant at P&lt;0.01.Leaf samples were analysed for micronutrient content (B, Fe, Mn, Cu and Zn). Symptoms of boron deficiency (“quilling” of the petals) were recorded and shown to be significantly correlated with the boron content of the leaves (P&lt;0.001). The copper content of plants grown without added micronutrients was well below the published critical level, and this deficiency is considered responsible for many of the effects observed.