MSc

The present investigation on the Evaluation of aquatic plants for water
gardening was carried out in the Department of Pomology and Floriculture,
College of Horticulture, Vellanikkara, Thrissur during the period 2006 – 2008
with the objectives of evaluating the aquatic plants suitable for water gardening
and standardizing the growing media for three species of water liliy, viz.,
Nymphaea rubra, N. alba and N. stellata.
Survey was conducted across Thrissur, Kozhikode and Palakkad districts
and 42 aquatic plants were collected. Evaluation of the collected aquatic plants
revealed that, wide variation existed in the vegetative and floral characters. Based
on their growth habit these plants were classified into deep water aquatics,
shallow water aquatics, submerged or oxygenator plants, floating plants, marginal
plants and bog plants. Twenty two aquatic plants suitable for water gardening at
different levels were identified.
Angelonia salicariaefolia, Crinum viviparum and Limnocharis flava were
found suitable to be grown as bog plants. The marginal areas of the water gardens
can be planted with Ipomoea aquatica and Hygroriza aristata etc. Aponogeton
monostachyon, Nymphaea alba, Nymphoides indica and Nymphoides peltata are
suitable for deep water areas. In shallow water areas Nelumbo nucifera can be
used. Azolla pinnata, Lemna minor, Eichhornia crassipes, Pistia stratiotes and
Trapa natans could be used as free floating plants. Utricularia australis, Najas
minor, Limnophila indica, Cabomba caroliniana, Ceratophyllum demersum,
Elodea canadensis and Hygrophila difformis can be grown as submerged plants.
They can also be used as aquarium plants.
Studies on three Nymphaea spp. revealed that Nymphaea stellata was
superior to the other two in all the vegetative parameters, except leaf length and
leaf longevity which were higher in Nymphaea rubra. Early flowering and
maximum flower production were also observed in Nymphaea stellata in which
the duration from bud emergence to complete flower opening was the minimum.
Length of the bud, flower size and longevity of flower were found to be the
maximum in Nymphaea rubra.
Among the media combinations studied, M1 [sand + clay (1:2)] was
superior over others with respect to all vegetative parameters, except leaf length,
which was maximum in M2 [sand + soil +clay (1:1:1)]. When the floral characters
were studied it was found that M2 [sand + soil +clay (1:1:1)] was superior to the
other media combinations. M3 [coir pith +soil + clay (1:1:1)] produced the
maximum number of propagules.
The study on the interaction effect of Nymphaea spp. and media revealed
that Nymphaea rubra in M2 [sand + soil +clay (1:1:1)] recorded the maximum
leaf length, leaf breadth, leaf area, pedicel length, bud length and flower spread. In
Nymphaea stellata, M1 [sand + clay (1:2)] recorded maximum petiole length and
M2 [sand + soil +clay (1:1:1)] recorded maximum flower production. In
Nymphaea rubra the time for complete unfurling of leaf and leaf longevity was
maximum in M3 [coir pith +soil + clay (1:1:1)] but, the flower longevity were
maximum in M4 [coir pith +clay (1:2)].