PhD

Experiments were conducted at the Department of Pomology and
Floriculture, College of Horticulture, Vellanikkara, during 1995-1997 to optimize
the shade, nutrients and growth regulators for cut flower production in Anthurium
andreanum var. 'Hawaiian Red'.
The effects of three growth regulators, viz., GA, BA and Ethephon with
two concentration each, 750 ppm and 1500 ppm, in combination with four nutrients,
viz., 1 % fertilizer complex, Hoagland solution, Knop's solution and Ohio solution,
were assessed at four levels of shade, viz., 80, 70, 60 and 50 per cent. Post harvest
studies were also carried out with an objective to prolong the longevity of cut
blooms, following different stage of harvest and giving different pulsing and hold-
ing treatments.
Results revealed that the different levels of shade and growth regulators
significantly influenced all the morphological characters of the plant, viz., height,
spread, number of leaves, leaf area, petiole length, number of branches and suckers.
Plant height was significantly superior under 80 per cent shade
(5.68 cm), 1 per cent fertilizer complex sprays (5.46 cm) and BA 750 ppm sprays
(6.11 cm), were superior individually. The superior treatment combination was 70
per cent shade + Knop's solution + 750 ppm BA (7.60 cm).
The maximum plant spread (EW - 20.13 cm and NS - 19.80 cm) was
under 80 per cent shade. Eighty per cent shade + Ohio solution + 1500 ppm BA
recorded the maximum EW spread (26 cm), while NS spread was maximum

(28.70 cm) in the treatment combination involving 80 per cent shade + 1 per cent
fertilizer complex + 750 ppm BA.
The best values of growth parameters were recorded under 80 per cent
shade and 750 ppm BA, viz., 14.03 and 14.02, respectively, for number of leaves
(9.29 and 10.79 cm, respectively) for petiole length, leaf length (7.76 and 8.33 cm,
respectively), leaf breadth (5.93 cm and 6.49 cm, respectively), index leaf area
(50.75 cm- and 59.60 cm-, respectively). Total leaf area (423.25 cm? and
517.56 cm>, respectively) and LAI (0.43 and 0.51, respectively) were maximum
under 70 per cent shade and BA 750 ppm. The superior combinations for these
parameters were 80 per cent shade + Ohio solution + 750 ppm BA, for highest
number of leaves (26.20); 80 per cent shade + Ohio solution + 1500 ppm BA for
highest petiole length (14.00 cm); 60 per cent shade + Hoagland solution + 750 ppm
BA for maximum leaf length (10.50 cm) and 60 per cent shade + 1 per cent
fertilizer complex + 750 ppm BA for maximum leaf breadth (8.0 cm). The
treatment combination involving 70 per cent shade + 1500 ppm BA with Hoagland
solution was the best for maximum index leaf area (90.90 cm-) while same with 1
per cent fertilizer complex was the best for total leaf area (872.00 cm-) and LAl
(0.89).
Branching started only after 6 months from the commencement of the
experiment. It was one month earlier under 80 per cent and 70 per cent shade levels.
Significantly superior branching was observed under 80 per cent shade (2.29),
fertilizer complex (2.13) and GA 750 ppm (2.37), individually. Treatment
combination involving 80 per cent shade + 1 per cent fertilizer complex + 1500
ppm GA recorded the maximum branching (3.80).

.' .
Sucker production was the best under 80 per cent shade (1.35) and
750 ppm BA (1.35). Treatment combination involving 80 per cent shade + Ohio
solution + 750 ppm BA produced the maximum number of suckers (2.5) per plant.
Growth behaviour with respect to height, number of leaves, leaf area,
number of suckers and branches showed a linear trend. The linear growth rate was
consistent and positive under the treatment combination of 80 per cent shade + Ohio
solution + 750 ppm BA.
Dry matter production was significantly superior under higher shade
intensity and lower concentration of BA. The dry weight ratio of shoot:root was the
highest (2.15) under the treatment combination of 80 per cent shade + Knop's solu-
tion + 750 ppm Ethephon.
Leaf longevity was significantly highest (161 days) in the treatment
combination, 70 per cent shade + 1 per cent fertilizer complex + 750 ppm BA.
Stomatal distribution and size were not influenced significantly by the
treatments. Leaf senescence, though was influenced significantly, no particular
trend was observed.
The aerial root production decreased significantly with decrease in shade
intensity. Primary and secondary roots and root spread were the highest under 80
per cent shade and BA 1500 ppm. Maximum root length was observed under 60 per
cent shade.
Flowering with small stalkless flowers was first observed under 50 per
cent shade with GA 750 ppm, at the age of 8 months. Inflorescence with normal size

were produced at the age of 13 months, first under 80 per cent shade followed by 70
per cent, 60 per cent and 50 per cent. The time taken for various stages of flower
development and the number of inflorescence produced per plant were not
influenced significantly.
Chlorophyll content in leaf was significantly influenced by shade levels.
There was a decrease in chlorophyll content with decrease in intensity of shade.
Eighty per cent shade and 1500 ppm Ethephon was superior with respect to the
content of green pigments. The highest total chlorophyll content was observed in the
treatment combination involving 60 per cent shade + Ohio solution + 750 ppm
Ethephon (8.8 mg g -1 fresh weight). Anthocyanin content was not influenced by any
of the treatments or combinations.
The leaf nutrient content and uptake of nutrients was maximum under 80
per cent shade and BA 750 ppm, individually.
Post harvest studies showed that the right stage of harvest of
inflorescence was when 1/3 flowers were open on the spadix. Inflorescence
harvested at this stage with medium to large size spathe lasted for a longer period
(23.33 days). Among the pulsing treatments, BA 50 ppm for 12 hrs, recorded
maximum vase life (20.00 days).
Among the different holding solutions tried, 8-HQ 30 ppm, BA 20 ppm
and Triadimefon 30 ppm recorded the optimum values of PL W, uptake of vase
solution, change in pH and EC, and recorded late spathe blueing, late spadix
necrosis and high gloss retention. Highest vase life period (27.00 days) was recorded
in 8-HQ 30 ppm (25.00 days) and Triadimefon 30 ppm (25.00 days). Among the


combinations tried, BA 20 ppm + Bavistin 0.1 per cent showed longest vase life
(23.67 days).
Maximum net profit per pot (Rs.204.60) was recorded by the treatment
combination involving 80 per cent shade + Ohio solution + 750 ppm BA.