30 research outputs found
Oospore shedding in Sargassum wightii (Greville) J. Agardh and Turbinana conoides (J. Agardh) Kuetzing at different environmental factors
Experiments were conducted with the receptacles of reproductive plants of Sargmsum wight;;
(Greville) 1. Agardh and Tllrbinaria conoides (1. Agardh) KuelZing to study the effect of
different environmental factor.; on the oospore output. The ability to liberate spores and the
quantity of spores shed in these two brown algae varied under the environmental factors
tested. In general, submerged condition of plants, long day condition at low illuminance,
seawater of 30 to 40%. salinity and 25 to 35'C temperature were found to be suitable for
maximum shedding of oosporcs in these two algin yield ing plants
Studies on sporulation in some commercially important marine algae of Mandapam coast
Marine algae are macroscopIC plants constituting an important
marine living renewable resource. They are used as human food, livestock
feed and fertilizer for land plants in many parts of the world besides having
the prime importance of being the only source for the production of agar,
carrageenan and alginates. These phytochemicals are extensively used in
various industries such as food , confectionery, textile, pharmaceutical,
cosmetics, dairy, liquor, canning, paint, varnish, paper etc. mostly as
gelling, stabilising and thickening agents and have an estimated billion
dollar global market (Zilinskas and Lundin, 1993). A summary of sources,
chemical composition, properties and important applications of these
phytochemicals given by Nambisan (1998) is presented in Table 1.
The commercial exploitation of seaweeds is going on since 1966 and
the export of economically important seaweeds such as Gelidiella,
Gracilaria and Sargassum was banned by the Govt. of India in 1975 as agar
and algin industries were started in India by 1970. In recent years many
industries producing these phytochemicals have come up in India but as yet
the production do not meet the demand. The annual demands of raw
materials by Indian seaweed based industries are 2000 tonnes and 12,000
tonnes (dry weight) of agarophytes and alginophytes respectively. Annually,
about 60 tonnes of agar and 500 tonnes of alginates are produced. In India
carrageenan is not yet produced. However its demand is nearly 200 tonnes
per year. Since the indigenous production of agar and alginates is unable
to meet the increasing demand, India is importing about 10-12 tonnes of
pharmaceutical grade agar, 35 tonnes of algi nates and 140 tonnes of
carrageenan costing foreign exchange of about Rs.10 crores (Zaidi et al.,
1999) This is mainly due to the paucity of raw materials particularly agar
yielding seaweeds
Sporulation in Gracilaria crassa Harvey ex. J.Agasdh at different environmental factors
Effect of environmental factors such as exposure to air and desiccation, salinity,
temperature, light and photoperiod on tetra spore shedding in the red alga Gracilaria crassa
was studied under laboratory condition. In the tetrasporic thalli exposed to air in shade and
sun for different durations, maximum quantity of spores were liberated from the thalli in
submerged condition in control experiment. Spore output was observed at salinity ranging
from 10 to 40% with peak output at 30%. Spore discharge was found at temperature ranging
from 20 to 40' C with maximum quantity of spore liberation at 25OC. Spore shedding was
recorded at light intensity ranging from 10 to 100 p Em2S-I with peak discharge at
20 p Em4S-I. Maximum spore release occurred in long day condition at 12 : 12 LD cycle
A new species of Heterospio (Annelida, Longosomatidae) from the Indian Ocean
Knowledge about the taxonomy and distribution of the monogeneric polychaete family
Longosomatidae Hartman, 1944 is limited in all parts of the world. A new species of the genus
Heterospio Ehlers, 1874 (Annelida, Longosomatidae) is described from the Indian Ocean. Heterospio
indica sp. nov. is mainly characterised by the conspicuous fl attening of the distal half of capillary chaetae
located in anterior elongated segments. Several body characters of high taxonomic relevance in the
genus are examined under the SEM and discussed. The 18S SSU rDNA and COI genes were sequenced
and represent the fi rst sequencing of a species of Heterospio, and the sequences have been deposited in
GenBankMinisterio de Economía y Competitividad; CGL2014-53332-C5-3-
Not Available
Not AvailableExperiments were conducted with the receptacles of reproductive plants of Sargmsum wight;;
(Greville) 1. Agardh and Tllrbinaria conoides (1. Agardh) KuelZing to study the effect of
different environmental factor.; on the oospore output. The ability to liberate spores and the
quantity of spores shed in these two brown algae varied under the environmental factors
tested. In general, submerged condition of plants, long day condition at low illuminance,
seawater of 30 to 40%. salinity and 25 to 35'C temperature were found to be suitable for
maximum shedding of oosporcs in these two algin yield ing plants.Not Availabl
Not Available
Not AvailableExperiments were conducted with the receptacles of reproductive plants of Sargmsum wight;;
(Greville) 1. Agardh and Tllrbinaria conoides (1. Agardh) KuelZing to study the effect of
different environmental factor.; on the oospore output. The ability to liberate spores and the
quantity of spores shed in these two brown algae varied under the environmental factors
tested. In general, submerged condition of plants, long day condition at low illuminance,
seawater of 30 to 40%. salinity and 25 to 35'C temperature were found to be suitable for
maximum shedding of oosporcs in these two algin yield ing plants.Not Availabl
Not Available
Not AvailableEffect of environmental factors such as exposure to air and desiccation, salinity,
temperature, light and photoperiod on tetra spore shedding in the red alga Gracilaria crassa
was studied under laboratory condition. In the tetrasporic thalli exposed to air in shade and
sun for different durations, maximum quantity of spores were liberated from the thalli in
submerged condition in control experiment. Spore output was observed at salinity ranging
from 10 to 40% with peak output at 30%. Spore discharge was found at temperature ranging
from 20 to 40' C with maximum quantity of spore liberation at 25OC. Spore shedding was
recorded at light intensity ranging from 10 to 100 p Em2S-I with peak discharge at
20 p Em4S-I. Maximum spore release occurred in long day condition at 12 : 12 LD cycle.Not Availabl
A new species of <i>Heterospio</i> (Annelida, Longosomatidae) from the Indian Ocean
Knowledge about the taxonomy and distribution of the monogeneric polychaete family Longosomatidae Hartman, 1944 is limited in all parts of the world. A new species of the genus Heterospio Ehlers, 1874 (Annelida, Longosomatidae) is described from the Indian Ocean. Heterospio indica sp. nov. is mainly characterised by the conspicuous flattening of the distal half of capillary chaetae located in anterior elongated segments. Several body characters of high taxonomic relevance in the genus are examined under the SEM and discussed. The 18S SSU rDNA and COI genes were sequenced and represent the first sequencing of a species of Heterospio, and the sequences have been deposited in GenBank.</p
<span style="font-size:13.0pt;mso-bidi-font-size: 10.0pt" lang="EN-GB">Record of bi-operculate fouling serpulid polychaete, <i style="mso-bidi-font-style:normal">Hydroides operculatus</i> (Treadwell, 1929) from Diu, west coast of India </span>
381-384Present study consists the documentation of
the bi-operculate form of fouling serpulid polychaete,<i style="mso-bidi-font-style:
normal"> Hydroides operculatus Treadwell, 1929 for the first time from India. It is
provided for the first time from India. This variant was found in samples
collected from Diu, North West coast
of India. A perusal of literature indicates that the bi-operculate form is an
advanced ontogenic stage of the polychaete rather than a different taxon. Such
stages are transient and therefore rarely seen in natural populations.
Polychaete species identification is intrinsic to many ecological and
environmental studies. Therefore the present documentation will help prevent
possible taxonomic confusion due to the presence of dual functional opercula
A review on the distribution of Phylum Phoronida from India with recent observations on <em>Phoronis psammophila</em>
1941-1943Phoronida is one of the smallest and least familiar phyla. A brief review on the distribution of Phylum Phoronida from India along with current observations on Phoronis psammophila is presented in this article. The aim of the study is to document the records of phoronids from Indian coast