Trends in Biosciences 8(6), Print : ISSN 0974-8431, 1435-1438, 2015 Studies on Floral Biology of Tuberose (Polianthes tuberosa) P. RANCHANA AND M. KANNAN Department of Floriculture and Landscaping, Tamil Nadu Agricultural University Coimbatore- 641 003 email: [email protected] ABSTRACT price to France, Italy and other countries (Anon, Knowledge of anthesis and the mode of pollination of 1994). There are only a few ornamental varieties a crop is a must for successful hybridization. of tuberose are known viz.,Calcutta Single, Calcutta Polianthes tuberosa Linn. is an important bulbous Double, Hyderabad Single, Hyderabad Double, ornamental crop, widely cultivated for cut flower, loose Kahikuchi Single, Mexican Single, Navsari Local, flower and extraction of essential crop but the floral Pearl Double, Phule Rajani, Prajwal, Pune Single, biology was poorly documented. Hence, an attempt was Shringar, Suvasini, Vaibhav and Variegated Single made to study the floral biology of ten commercially (Sharge, 1976 and Kuang et al., 2001). Single type important tuberose genotypes for its successful is also used for production of essential oil, but yield improvement in breeding studies and the findings are is less. Hence there is a need to develop a specific presented in this communication. variety for higher yield and essential oil purpose. To fulfil this objective research project entitled Key words Tuberose, flowers, single types, pollen “Development of F1 hybrids in tuberose (Polianthes tuberosa Linn.) for higher flower, concrete yield Flowers are one of the most important and and resistance to nematode” has been taken up in unique gift of nature. They are the adornments of TNAU, Coimbatore. In the same context flower the world with their valuable aesthetic, biology of all the planted genotypes have been environmental, economic and medicinal properties. investigated and presented here. The cut flowers like rose, carnation, gladiolus, MATERIALS AND METHODS tuberose, chrysanthemum, etc have commonly and frequently demanded in both the local as well as The material used for the study was 10 single international market. Among them, tuberose and five double type genotypes. Bulbs of the (Polianthes tuberosa) is one of the most important genotypes were planted at 45 x 20 cm spacing. All cut flower. It is an ornamental bulbous plant, native the plants were grown under uniform cultural of Mexico and belongs to family Amaryllidaceae. conditions. Observations were recorded for days Ornamental plants have prime importance in to first floret opening, floret diameter, hundred maintaining ecological balance and checking flower weight, bud colour, floret colour, row of pollution in surroundings. About 45% of world petals, no. of petals per floret, no. of pistils, no. of trade in floriculture products goes to cut flower. anthers, length of the anther, length of the pistil, In India, it occupies a prime position in the filament length, anthesis time, stigma receptivity floriculture industry. Waxy white flowering spikes and anther dehiscence. of single as well as double flower tuberose impregnate the atmosphere with their sweet RESULTS AND DISCUSSION fragrance and longer keeping quality of flower The studies on floral biology viz., flower spikes (Sadhu and Bose, 1973 ; Benschop, 1993) morphology, pollination behavior and barriers in and are in great demand for making floral pollination of any crop is very important for crop arrangement and bouquets in major cities of India. improvement. Tuberose is a cross pollinated crop It is widely grown as specimen for exhibition and and the fundamental information viz., anthesis, cut flower. It is extensively cultivated on a large stigma receptivity, pollen viability and fertility etc., scale in Tamil Nadu, Karnataka, West Bengal and are much needed for programming crop Maharastra. To a lesser extent it is also grown in improvement through hybridization. Observations Andhra Pradesh, Haryana, Delhi, Uttar Pradesh and on various parameters are presented in Table 1 and Punjab. Its essential oil is exported at an attractive 2. The flower morphology of tuberose genotypes 1436 Table 1. Floral biology of tuberose genotypes (single) S. No. Genotypes (Single) Calcutta Hyderabad Kahikuchi Mexican Navsari Phule Rajani Prajwal Pune Single Shringar Varieg- SE (D) CD Single Single Single Single Local ated (0.5) Single Days to first floret 101.23 101.05 99.01 98.02 101.03 98.21 98.01 99.04 99.01 101.05 2.31 5.64 opening (days) Floret diameter (cm) 4.65 4.72 4.81 4.76 4.63 4.75 4.89 4.73 4.71 4.64 0.26 0.58 Bud length 6.32 6.25 6.46 6.31 6.31 6.37 6.45 6.12 6.36 6.35 0.23 0.48 (cm) Hundred flower 115.18 117.78 117.42 118.31 117.32 118.21 170.31 118.21 117.42 117.32 2.62 5.31 weight (g) Bud colour green green green colour with green green green colour with green colour with green green green dark pink tinch at slight pink tinch at dark pink tinch at 8 Trends (6), in Biosciences 2015 the tip of the the tip of the floret the tip of the floret floret Floret colour White White White White White White White slight pink White White White tinch at the tip of the floret Row of petals 1 1 1 1 1 1 1 1 1 1 1 Number of petals per 6 6 6 6 6 6 6 6 6 6 6 floret (nos.) Number of pistils 1 1 1 1 1 1 1 1 1 1 1 (nos.) Length of the stamen 1.12 1.15 1.21 1.22 1.21 1.11 1.12 1.16 1.21 1.12 0.09 0.19 (cm) Length of the pistil 3.83 3.43 3.45 3.62 3.43 2.62 3.59 3.53 3.67 3.13 0.18 0.37 (cm) Filament length (cm) 3.12 3.11 3.09 3.12 3.15 2.11 3.12 3.13 3.13 2.98 1.11 2.34 Anthesis time 3.45 to 4.50 3.45 to 4.50 p.m 3.45 to 4.50 p.m 3.45 to 4.50 3.45 to 4.50 3.45 to 4.50 p.m 3.45 to 4.50 p.m 3.45 to 4.50 3.45 to 3.45 to 3.45 to p.m p.m p.m p.m 4.50 p.m 4.50 p.m 4.50 p.m Stigma receptivity three days after three days after three days after three days three days three days after three days after three days three days three days three days anthesis anthesis anthesis after anthesis after anthesis anthesis after anthesis after after after anthesis anthesis anthesis anthesis Anther dehiscence 5.45 pm to 5.45 pm to 7.30 5.45 pm to 7.30 5.45 pm to 5.45 pm to 5.45 pm to 7.30 pm 5.45 pm to 7.30 5.45 pm to 5.45 pm to 5.45 pm to 5.45 pm to 7.30 pm pm pm 7.30 pm 7.30 pm pm 7.30 pm 7.30 pm 7.30 pm 7.30 pm RANCHANA and M. KANNAN et al., Studies on Floral Biology of Tuberose (Polianthes tuberosa) 1437 Table 2. Floral biology of tuberose genotypes (double) S.No. Genotypes (Double) Calcutta Hyderabad Pearl Suvasini Vaibhav SE(D) CD Double Double Double (0.5) Days to first floret 107.76 108.21 106.32 104.56 105.63 1.34 3.21 opening (days) Floret diameter (cm) 5.34 5.08 5.23 5.78 5.67 0.24 0.49 Bud length (cm) 7.06 7.32 7.29 7.56 7.41 0.16 0.37 Hundred flower 267.73 265.42 269.87 272.20 271.98 1.75 4.32 weight (g) Bud colour green Green green green colour with dark green colour with pink tinch at the tip of dark green tinch at the floret the tip of the floret Floret colour White White White white with slight pink White White tich at the tip of the floret Row of petals 3-4 3-4 3-4 3-4 3-4 3-4 Number of petals per 13 - 14 13 - 14 13 - 14 13 - 14 13 - 14 13 - 14 floret (nos.) Number of pistils 1 1 1 1 1 1 (nos.) Number of anthers - - - - - - (nos.) Length of the stamen - - - - - - (cm) Length of the pistil - - - - - - (cm) Filament length (cm) - - - - - - Anthesis time 3.45 to 33.45 to 3.45 to 3.45 to 5.30 p.m 3.45 to 5.30 p.m 3.45 to 5.30 p.m 5.30 p.m 5.30 p.m 5.30 p.m Stigma receptivity - - - - - - - Anther dehiscence - - - - - - - showed that there were six, long radiating anthers genotypes (both single and double types) was (1.11 to 1.16 cm) and the pistils (2.62 to 3.83 cm) between 3.45 to 5.30 pm and it increased gradually, in single genotypes. The stamens contain profuse reaching the peak at 6.30 pm beyond which no yellow pollen. The pistil possessed three celled flowers opened. This is in agreement with the ovary which formed an ellipsoidal capsule. The findings of Uma, 1990 who stated that the period individual flower weighed 2.52 g. This was in of bud opening in tuberose was between 5.30 p.m. accordance with the results reported by Shen, et to 6.30 p.m. and maximum mean percentage of al., 1987 and Uma, 1990. Number of days taken anther dehiscence in tuberose genotypes (single) for appearance of first flower from planting varies was observed between 3.45 to 5.30 pm and the from 98 to 101 days in single types and it varies stigma receptivity was assessed by carrying out from 103 to 105 days in double types.