STUDIES ON EFFECT OF PLANT GROWTH  REGULATORS ON GROWTH, FLOWERING,  SEED YIELD AND QUALITY IN ZINNIA  (Zinnia elegans Jacq.)

ILAVARA BRAHMANI

STUDIES ON EFFECT OF PLANT GROWTH REGULATORS ON GROWTH, FLOWERING, SEED YIELD AND QUALITY IN ZINNIA (Zinnia elegans Jacq.)

Date

2019-08-06

Authors

ILAVARA BRAHMANI

Publisher

COLLEGE OF HORTICULTURE, VENKATARAMANNAGUDEM, W. G. Dist – 534 101 ANDHRA PRADESH

Abstract

The present investigation entitled “Studies on effect of plant growth regulators on growth, flowering, seed yield and quality in zinnia (Zinnia elegans Jacq.)” was conducted at College of Horticulture, Venkataramannagudem, West Godavari district of Andhra Pradesh during 2018-2019. The experiment was laid out in factorial randomized block design (FRBD) with 3 replications comprising 21 treatment combinations which include first factor with three levels of varieties (Lilliput, Gaint California, Dahlia flowered double mix) and second factor with seven levels of growth regulators (Water spray, GA3 @ 100 and 200ppm, NAA @ 50 and 100ppm, Triacontanol 50 and 100ppm). Based on the results obtained from the experiment showed significant differences among the varieties, growth regulators and their interactions on all the parameters. The cv. Gaint California sprayed with GA3 @ 200 ppm was considered as best treatment combination based on the several positive results recorded on vegetative parameters like Plant height, number of branches plant-1 , plant spread, number of leaves plant-1 , leaf area plant-1 , internodal length, total chlorophyll content and dry weight of plant. From the investigation conducted, it can be concluded that the treatment combination cv. Gaint California sprayed with GA3 @ 200 ppm showed significant influence on physiological parameters, phenological stages like days taken to emergence of first flower bud, opening of first flower bud, 50% flowering, 100% flowering, first harvest of the flowers and flower quality parameters like flower diameter, flower stalk length, longevity of flower on plant. The same treatment combination was found best with respect to flower yield parameters like number of flowers plant-1 , plot-1 , number pickings plant-1, flower yield plant -1 , plot-1 and seed parameters like days taken to seed setting, seed yield flower-1 , plant-1 . Whereas cv. Lilliput plants sprayed with water was recorded minimum values regarding all the vegetative, floral and seed yield parameters. Based on the results from the second experiment, regarding seed quality parameters like germination percentage, seedling length, seedling vigour index cv. Gaint California sprayed with GA3 @ 200 ppm was found to be best treatment than other treatments, whereas cv. Lilliput plants sprayed with water was recorded minimum values regarding seed quality parameters. It may be recommended that cv. Gaint California sprayed with GA3 @ 200 ppm is considered to be the best treatment combination for commercial cultivation of zinnia as a cut flower and garden purpose by the supply of good quality seeds under the existing coastal climatic conditions of Andhra Pradesh. Zinnia flower production can be popularized among the floriculture farmers for continous production of flowers along with major flowers to generate income throughout the year.

Description

1. Studies on effect of different spacings and sowing dates on growth and yield of zinnia need to be conducted. 2. The effect of growth inhibitor chemicals alone or along with the growth promoting hormones has to be studied for the better landscape performance. 3. The influence of seasonal variations in different cultivars of zinnia can be studied. 4. The influence of bio fertilizers at different doses can be studied.