Indian J. Hort. 67(2), June 2010: 255-259 Impact of certain chemicals on vase-life of different cultivars of China aster and gladioli A.K. Tiwari*, B.D. Bhuj and S.K. Mishra V.C.S.G. College of Horticulture, G.B. Pant Univ. of Agriculture & Technology, Bharsar, Pauri Garhwal 246 123 ABSTRACT Two set of experiments were carried out to investigate the effect of vase solution made of different chemicals on vase-life and quality of cut flowers of gladiolus and China aster cultivars. Out of the four vase solutions applied, the treatment with 200 ppm citric acid, 200 ppm AgNO 3 , 5% sucrose and 0.02% Tween-20 was observed to be the best followed by 200 ppm citric acid, 200ppm CoNO 3 , 5% sucrose and 0.02% Tween-20, resulting in the longest vase-life and maximum weight gain at third day and total solution uptake. Correlation revealed that floret diameter had a strong positive correlation with loss in weight of vase solution up to ninth day, total weight loss of vase solution, floret opening per cent and vase-life in various cultivars of both crops. Key words: Preservatives, vase solution, vase-life, China aster, gladioli. INTRODUCTION Gladiolus is an important florist crop popular as cut flower in the domestic and international market. The spikes are highly perishable and need to send market immediately after harvest. China aster is one of the most popular of all garden annuals grown throughout the world. The vase-life of China aster cut flowers is in general more other than that of other annuals grown for cut flowers. Post harvest treatments are aimed at preferentially encouraging the process under quality traits, including flower size, flower opening, shape, colour and longevity. Use of floral preservatives at all stages of flower handling and marketing is known to improve the flower quality, longevity and better consumer acceptability. According to concentration and time of application, preservative solutions may be classified into three groups viz., pulsing solution, vase solution and bud opening solution (Bhattacharjee, 2). Vase solutions are meant to hold flowers continuously till the termination of their vase-life. The main constituents of floral preservatives are water, sugar and biocides. Besides mineral nutrients, acidifying agents, anti-ethylene compounds and growth regulators are also used in floral preservatives. It has been shown that antimicrobial compounds in the vase solution prolong the vase-life. Singh et al. (8) conducted trial on various biocides in vase solution and found that biocides effectively controlled bacterial growth but did not increase vase-life appreciably. Their efficacy increased only when used along with sucrose. Prolonging the vase-life depends on water balance and retardation of senescence which can be achieved by the use of sucrose and certain chemicals (Beura and Singh, 1). Since, ethylene plays critical roles in flower senescence; it is desirable to inhibit the ethylene action. The inhibitors used for such action are CO 2 , silver ions and cyclic olefins (Nowak, 6). Although, the involvement of plant growth hormones in senescence process of flowers has been thoroughly investigated, however, the actual mechanism of action still is not clear (Bhattacharjee, 2). Therefore, present investigation was planned to study the relative impact of certain chemicals on vase-life of different cultivars of China aster and gladioli. MATERIALS AND METHODS The two cultivars of gladiolus (White Friendship and Nova Lux) and two cultivars of China aster (Kamini and Shashank) were used for this investigation. The flowers were harvested in the afternoon using sharp knives. Gladiolus spikes were cut when basal floret just showed colour whereas, China aster flowers were cut at paint brush stage and immediately put in the bucket containing cold water. The basal portion of stems was re-cut at 2 cm from the point of previous cut. Selected three cut flowers of all cultivars were put in the each graduated conical flask having 4% sucrose, 200 ppm citric acid, 0.02% Tween-20 plus 200 ppm of various chemical compounds like AgNO 3 , CoNO 3 , ABA and 2,4-D. Distilled water with 4% sugar, 200 ppm citric acid and 0.02% Tween-20 was treated as control. The treatments were replicated five times in completely randomized design at ambient temperature of 21-22°C coupled with 80% humidity. The fresh weight and changes in weight of each flower was recorded using digital analytical balance. Observations were recorded *Corresponding author’s E-mail: drajaitiwari_7@rediffmail.com