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Genus Momordica (Cucurbitaceae) has wide range of distribution
in India and in South Asia. Western Ghats, one of the megadiversity
hostspots, hold a rich treasure of diversity in Momordica. L., it comprises
M. charantia var. muricata, M. charantia var. charantia, M. dioica and
M. sahyadrica (Joseph & Antony, 2008). M.cymbalaria Fenzl. is a
species, which occurs in Indian state of Karnataka and Andhra Pradesh.
Sweet gourd (M. cochinchinensis Spreng.) is an indigenous species of
South - East Asia and belongs to Cochinchina region of northern
Vietnam. Also grown in China, the species is a popular vegetable of
Assam in India (Shadeque & Baruah, 1984). M. balsamina, referred to
balsam apple, balsam- pear or African pumpkin, is common in Namibia,
Botswana, Swaziland and South Africa and is widely distributed in
tropical Africa, Asia, Arabia, India and Australia (Thakur et al., 2009).
Spinegourd (Momordica dioica Roxb. ex Willd.) of Cucurbitaceae
is a perennial dioecious climber with tuberous roots. Taxon Momordica
dioica Roxb. ex willd., has been verified by U.S. Dept. of Agriculture as
member of family Cucurbitaceae, subfamily
Cucurbitoideae, tribe
Joliffieae and subtribe Thladianthinae as updated on 28 th May, 2009.
Genus name Momordica could perhaps refer to sculptured seed or uneven
appearance of fruit, which look as if they have been bitten. Latin Mordeo
means, to bite, but this explanation is doubtful (Jackson, 1990).The plant
commonly known as ‘Kakora’ in Gwalior Chambal Division of M.P., is
supposed to have originated in Indo- Malayan region (Rashid, 1976 &
Singh, 1990). In India it is distributed widely from Himalayas to Southern
peninsula and amongst other parts of Indian subcontinent including
Pakistan, Bangladesh, Myanmar and Sri Lanka, growing wild and mostly
cultivated for its fruit which is used as a vegetable (Sastri, 1962; Singh et
al., 2009). The fruit is oval with soft spines. Aerial part of the plant dies
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at the beginning of winter. Plant perennates through sprouting of tubers at
the onset of monsoon. Late arrival or failure of monsoon causes a serious
threat for the sprouting and survival of the plant and creates a big
production loss. The species is cultivated by vegetative propagation
method from underground tuberous roots. Propagation by cuttings is not a
common practice. Seed germination is difficult due to hard seed coat and
seed dormancy, posing a serious problem for uniform and early seed
germination. Spinegourd or “Kakora” is a popular vegetable in Gwalior –
Chambal division of the state of Madhya Pradesh in India. The fruit is
collected by tribal people and other inhabitants from the forest. It is also
cultivated by local farmers. A large quantity of the fruit is exported to
Delhi, Agra, Gwalior and other urban area of the country. Some quantity
is also sold in the local markets. Thus constituting an important cash crop
for Gwalior-Chambal and generating an annual yield of around one crore
in Indian currency for the area (self survey), the plant is of great
economic and commercial value for the local area.
Perusal of literature shows that there is hardly any study pertaining
to the eco-physiology, growth, development and nutritional qualities of
the plant. Study related to growth and development of commercially
important M.dioica will, therefore, be of high value and may infuse better
cultivation practices to obtain a better yield. Since such attempt seems to
lack so far, hence the study has been undertaken.
Momordica dioica, a plant of great medicinal values, is used for the
treatment of eye diseases, poisoning, bleeding piles, urinary, bowel
problems and as an expectorant. Juice of root is stimulant, astringent and
antiseptic (Kirthikar & Basu, 1981). Plant is also used in fever (Satyavati
et al., 1987). Fruits, leaves and tubers are used in India as a folk medicine
in diabetes (Sadyojatha et al., 1996). Its wild relative gac fruit
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(Momordica cochinchinensis Spreng) is a good source of macronutrients
as well as calcium and phosphorus and yields 523 KJ of energy per 100
g of edible portion of gac fruit (Vien,1995) . Gac fruit pulp, seed
membrane and oil show high bioavailability of lycopene and B-carotene
along fatty acids (Aoki et al., 2002). A thirty day supplementation trial in
Vietnam found that daily consumption of gac fruit significantly improved
plasma- levels of retinal, alpha and beta – carotenes and lycopene in preschool children (Vuong, 2000; Burke et al., 2005). Shreedhar et al.
(2001) have found the aqueous and ethanol extracts from the root of
Momordica dioica most effective in causing significant abortifacient
activity in female rats, the extracts showed moderate estrogenic activity.
Study carried out by Kameswara rao et al.(2003) revealed that the oral
treatment with aqueous extract of Momordica cymbalaria fruit (0.5 g/
kg) for 6 weeks showed a significant antihyperglycemic as well as
antihyper-lipidemic effects in the alloxan – induced diabetic rats.
Thakur et al. (2009) have studied the medicinal and neutraceutical importance of Momordica balsamina, a wild relative of
Momordica dioica. This plant is used as a traditional folk medicine in
many countries. The leaves, fruits and bark of plant contain resins,
alkaloids, flavonoids, glycosides, steroids, terpenes, cardiac glycosides,
saponins having anti-HIV, anti- plasmodial, shigellocidal, anti- diarrheal ,
antiseptic, antibacterial, antiviral, anti-inflammatory, anti-microbial,
hypoglycemic, antioxidant, analgesic and hepato-protective properties.
They have reported that therapeutic agent Momordin of this plant is
capable of inhibition of the growth of the HIV and other viruses. Leaves
of this plant are also important source of the nutrients having 17 amino
acids with adequate minerals like potassium, magnesium, phosphorus,
3
calcium,
zinc,
manganese
and
iron.
Plant
can
be
used
for
biopharmaceutical and neutraceutical purposes.
Antihyperglycemic activity of chloroform, ethylacetate and alcohol
extracts of Momordica dioica fruits has been studied by Thirupathi et al.
(2006) in alloxan-induced rats. Phytochemical screening showed positive
test for CHCl3 extract, steroids and /or triterpenoids and their glycosides
for ethyl acetate and ethyl alcohol. The ethyl acetate and ethanol extract
have shown significant anti- diabetic activity at a dose of 200 mg/kg.
Their study revealed potential antidiabetic activity. Whereas roots of
Momordica cymbalaria, a wild relative of Momordica dioica, have
shown antiovulatory and abortifacient potential in ethanolic extract in
rats, in a study carried out by Koneri et al. (2006). In their study, female
Wister albino rats (150-200 g) with at least three regular estrous cycles
were administered with ethanolic extracts of roots of M. cymbalaria at
the two doses 250 and 500 mg /kg orally for 15days.The animals were
sacrificed on 16th day. One ovary was subjected to histopathological
studies and other for biochemical studies. Abortifacient study was done in
another set of three groups of animals. Extract at doses of 250 and 500
mg /kg were administered orally through gastric gavages from the day 6
to the day 15 of the pregnancy. Animals were lapartomised in 19 th day of
pregnancy. Highly significant
(P<0.01)
decrease in the duration of
estrous cycle and metaestrous phase and increase in pro-estrous phase
was seen , but diestrous phase was unchanged in both 250 and 500 mg
treated groups when compared to untreated group. Study revealed that
ethanolic extract at both doses (250 mg and 500 mg /kg) showed
significant antiovulatory activity. It is abortifacient at 500 mg/kg, but not
at 250 mg/kg.
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Jain et al. (2008) have studied the hepatoprotective activity of
ethanolic and aqueous extracts of Momordica dioica Roxb ex willd. In
this study leaves were evaluated against CCl4 - induced hepatic damage in
rats. The extracts at dose of 200mg/ kg were administered orally once
daily. The substantially elevated serum enzymatic levels of serum
glutamate oxaloacetate transaminase (AST), serum glutamate pyruvate
transaminase (ALT), serum alkaline phosphatase (SALP) and total
bilirubin were restored towards normalization significantly by the
extracts. Silymarin was taken as standard reference and exhibited
significant hepatoprotective activity against CCl4 -induced hapatotoxicity
in rats. Again Jain et al. (2009) have studied the effect of ethanolic
extract of the fruits of Momordica dioica for its protective and curative
properties against gentamycin- induced acute renal injury in albino rats of
both sexes. Gentamycin intoxicated group showed significant increase in
blood urea (69.48 ± 4.34mg/dl) and serum creatinine (3.017 +
0.208mg/dl) from normal levels (33.72 + 1.92 and 0.818 + 0.073mg/dl) in
control group. In the preventive regimen, the extract at dose levels of 200
mg/kg showed significant reduction in the elevated blood urea (47.93 +
2.46mg/dl) and serum creatinine (2.067 + 0.1745mg/dl) respectively. This
treatment was found effective in normalizing the histopathological
change compared to the intoxicated rats.
Cardioprotective effect of Momordica cymbalaria holds medicinal
value and is used traditionally for the treatment of various disorders
including the cardioprotective potential in a study carried out by Raju et
al. (2008). In this study pre-treatment with ethanolic extract of M.
cymbalaria at 250 and 500 mg/ kg prevented the elevation of serum
marker enzymes, lactate dehydrogenase (LDH), creatinine kinase – MB
fraction (CK – MB), Asparate transaminase (AST), alanine transaminase
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(ALT), Alkaline phosphatase (ALP) and oxidative stress marker like
lipid peroxidase (LPO) , catalase
and superoxide dismutase in
isoproterenol – induced myocardial injury in rats.
Plant (M. dioica) has also been tested for its antiulcer activity
(VijayKumar et al., 2011). In their study, hydro-alcohol extract of
M.dioica fruit at the dose of100, 200 and 400 mg / kg Body weight, was
administered orally twice daily for 5-days for the prevention of pylorus
ligation-induced ulcers. A significant reduction in lesion – index was
observed in ulcer – induced animals pre-treated with extracts at different
doses when compared with ulcerated rats. A significant decrease occurred
in the level of H+ - K+ ATPase, volume of gastric juice and acid output.
Gastric wall mucosa and pH increased significantly. These results showed
antiulcer properties, augmenting the gastric defense mechanisms in rats.
Apart from ethno-botanical, medicinal and nutritive value of
Momordica dioica, several workers has studied the various aspects of this
and related genera. Rodriguez et al. (1976) have studied the caroteniod
pigment changes in ripening Momordica charantia fruits. They have
observed number of carotenoids increased from 5 in immature fruit to 6 at
the mature green and 14 at partly ripe to ripe stage. Phytochemical
investigations, carried out by Ghosh et al. (1981) and Ali and Srivastava
(1998) revealed the presence of traces of alkaloids and ascorbic acid in
the fruits. Lectins,  - sitosterol, saponin glycosides, triterpenes of ursolic
acid hederagenin, oleanolic acid,  -spiranosterol, stearic acid gypsogenin
and the presence of momordica -ursenol was also observed.
Ali et al. (1991) have studied the germination and propagation
techniques of Kakora (Momordica dioica Roxb). They observed the seed
germination at 300C but not at 200 or 250C when the seed coat was
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removed. There was no effect of gbberallic acid (GA3) on the germination
of intact seeds. Tuberous roots have no dormancy. Application of silver
nitrate (AgN03) at a concentration of 300 – 600 mgl-1 to the female plant
was effective in inducing bisexual flowers. Pollen viability of these
bisexual flowers was as high and effective as that of normal male flowers.
These pollens were found effective in producing fruits and seeds in
female flowers of the same, as well as of different plants. And the most of
the floral parts of bisexual flowers were bigger than those of the male and
female flowers.
Organogenesis in teaselgourd (Momordica dioica Roxb.) has been
studied by the Nabi et al. (2002). In their study they took four types of
explants namely node, shoot tip, leaf and cotyledon. The cotyledon
showed best performance in tissue culture conditions. Highest number of
multiple and tallest shoots were obtained on MS medium fortified with
1.0 mg/ l BAP and 0.1 mg/ 1 NAA. For rooting half strength MS
supplemented with IBA proved to be better than IAA. Although on half
strength of MS supplemented with IAA, tallest shoots were observed.
Morphological and physiological variation in 29 accessions of
Kakora (Momordica dioica Roxb.) and one wild relative (Momordica
cochinchinensis Spreng.) collected from different agroecological zones of
Bangladesh have been studied for 29 morpho-physiological characters by
Rasul et al. (2004). In this study, they have observed considerable
variations in the genotypes in which dissimilarity ranged from 4.6 to 58.6.
Cluster analysis based on this variation primarily classified M.dioica and
M. chochinchinensis into two groups and formed five clusters, in which
one cluster contained 24 M.dioica accessions. No relationship was found
between genetic divergence and geographical distribution of the
accessions, indicating no regional gene pool clustering.
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Gosh (2005) has studied the mechanism of monocorpic senescence
of Momordica dioica based on source – sink regulation by reproductive
organs. In his study he has observed higher average chlorophyll levels in
male plants than the female plants, whereas female plants show higher
degree of senescence than monoecious plants. Male plants showed less
senescence than female and monoecious plants.
Induction of octoploids in Kakora (Momordica dioica Roxb.) by
chromosome doubling through seed and multiple shoot treatments has
been studied by Yasuhiro et al. (2006). Seed treatments with 0.2, 0.4%
colchicines or 0.003% amiprophosmethyl were effective to double the
chromosomes, 0.4% colchicines was most effective. Amiprophosmethyl
treatment brought octoploid plants with high rate of seed germination. In
the same study multiple shoot treatments with 0.05% colchicines for12
and 24 hours and 0.1% colchicine for 24 hours also brought octoploid
plants. Leaf and guard cell size were bigger in these octoploids than
tetraploids, however, leaf shape index (Leaf length/ leaf width) was lower
in octoploids, when compared to tetraploids.
Joseph and Antony (2008) have done the ethnobotanical
investigations in the genus Momordica L. in Southern – Western Ghats of
India. They have studied the medicinal, cosmetic, culinary as food and
other uses of Momordica charantia var. muricata, M. charantia
var.charantia, M. dioica and M.sahyadrica. They have also studied the
vernacular names in local dialects, taboos and religious beliefs related to
their domestication and folk taxonomy in greater detail. In another study,
Joseph and Antony (2007) have studied the genetic erosion in genus
Momordica L. in south- peninsular India. They have found in this study
that the wild species of Momordica are subjected to varied types of
threats affecting their survival in India, especially in Peninsular India.
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They have used a numerical model for quantifying threat of genetic
erosion. Habitat loss and fragmentation brought about by population
pressure and developmental activities, poor distribution and low
population density of Momordica species coupled with inadequate in situ
conservation efforts are the major factors attributed to the severe-threats,
affecting their long term survival in the forest. Again, Joseph and Antony
(2008) have reported the occurrence of a new species Momordica
sahyadrica endemic to Western Ghats of India. Material of this species
was formerly placed under Momordica dioica, but it appeared distinct
from Momordica dioica in various morphological and ecological features.
Joseph et al. (2009) have studied the tuber morphology,
germination behavior and propagation efficiency in three Momordica
species in India. They have investigated that the tuber morphology of
Momordica dioica and M. sahyadrica is different from that of M.
subangulata ssp. Renigera, Momordica dioica and M. sahyadrica
develop taproot tuber with shoot sprout only at the caudex region,
whereas in M. subangulata ssp. renigera has both the taproot and
adventitious tubers with shoot sprout all over the tuber surface. Tubers of
M.dioica and M. sahyadrica are perennating, whereas in M. subangulata
ssp. renigera they serve as both perennating and propagation structures.
Momordica dioica and M.sahyadrica had prolonged tuber dormancy of 45 months, whereas M. subangulata ssp. renigera had short dormancy
period of about 2 months.
Growth characteristics including propagation methods, best time of
planting, productivity and the economics of cultivation of Momordica
dioica have been studied by Singh et al. (2009). In their experiment, they
collected 18 genotypes from various naturally growing forest areas. These
were planted during the month of July – August (2006). Growth and yield
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attributes and their co-relations were studied. High average yield 606 g/
plant and 649 g/plant were recovered in AA1/ 60-1 and AA1/S-4
genotypes respectively. Their study again reveals that this crop can also
be cultivated in the plains and urban areas where tropical and subtropical conditions prevail.
Pollen cryopreservation feasibilities in M.dioica and M. sahyadrica
have been studied by Rajsekharan et al. (2010). They have recovered
viable pollen grains after cryogenic storage in various proportions in
different Momordica species. There was a variable response to the
germination of cryopreserved pollen in Momordica species. Study can be
useful in establishing pollen cryobanks for Momordica species,
conserving nuclear genetic variations and maintaining genetically diverse
stock
Cytomorphological and molecular characterization of F1 hybrid
between Momordica dioica and Momordica subangulata sub sp. renigera
have been studied by Bharathi et al. (2011).They produced hybrids
between these two species, through bagging and hand pollination. These
F1 hybrids showed vigorous growth habit but less fertility. Meiotic and
mitotic
chromosome
behavior
along
with
randomly
amplified
polymorphic DNA (RAPD) analysis confirmed the interchanges of
genetic characters in new hybrids. These hybrids exhibited vigorous
foliage with intermediate flower characters, compared to parental species.
Self pollination and back crossing of F1 plants to either parent confirmed
the presence of both the male and female sterility. Time of anthesis (early
morning) was similar to that of pollen parent, whereas the size of leaf,
flower pedicel and plant growth were intermediate when compared to
parents. Somatic chromosome analysis revealed 2n =28 in M. dioica
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(female plant) and 2n =56 in M. subangulata ssp. renigera (male plant)
and in F1 hybrid 2n = 42 was observed.
An efficient protocol for regeneration of encapsulated shoot-tip
explants of spinegourd has been developed by Thiruvengadam et al.
(2012). In this study shoot-tip explants excised from in vivo proliferated
shoots were encapsulated in calcium alginate beads. A gelling matrix of
3% sodium alginate and CaCl2.2H2O was found suitable for the formation
of ideal calcium alginate beads. Maximum response (100%) for the
conversion of encapsulated shoot- tip explants
into plantlets was
obtained on 0.7% agar solidified full strength MS medium containing
0.5  M BAP(6–benzyl amino urine). Encapsulated shoot-tips could be
stored at low temperature (40c) up to 10 weeks with a survival frequency
of 50% well developed regenerated plantlets were hardened, acclimatized
and established in the field with 90% survival. The plants grew well
without any detectable variation.
Seed dormancy and germination has been the subject of study for
physiologists, ecologists and crop scientists for a long time. Hilhorst et al.
(1992) have concluded that the abscisic acid plays a pivotal role during
the development of primary dormancy in the seeds, and the gibberellins
are involved in the induction of germination. Both the synthesis and the
response to the hormones are controlled by the natural environmental
factors such as light, temperature and nitrate. Whereas Alboresi et al.
(2005) have emphasized the importance of nitrogen for dormancy and
plant development. According to them, nitrate is a signal molecule
controlling the seed dormancy in Arabidopsis. They have concluded that
a good accumulation of nitrate in mother plant and the seeds, leads to
lower dormancy. Exogenous supply of nitrate on seed germination
reveals that nitrate in contrast to glutamine or potassium chloride clearly
11
stimulated the germination of the dormant seeds in Arabidopsis. They
have also reported nitrate transporter NRT 1.1 (CHL 1) probably
conveying the nitrate signal into seeds.
Dormancy cycle and viability of buried seeds of Papaver rhoeas
have been studied by Cirujeda et al. (2006). In this experiment seeds of
three Spanish Papaver rhoeas population (two resistant to both the
tribenuron – methyl and 2, 4 – D and one susceptible to both herbicides)
were buried at various depths and tested for viability and germination.
Annual dormancy cycle was found similar for each population in 3 years.
Maximum germination occurred in September and December, and no
seed germinated in February and May. Burial depth influenced the
germination. Higher germination was recorded in the seeds, those buried
at 2 or 9 cm. Viability of the buried seeds decreased slowly throughout
the 77 months of experimental period. At the end of this period 53, 72
and 61% viability was recorded for the seeds buried at the 2, 8 and 20 cm.
respectively.
Vermicompost is nowadays very popular fertilizer alternative. But
Ievinsh (2011) have observed the negative effect of solid vermi-compost
and vermicompost extract on seed germination and early seedling
development in vegetable crops. He has studied that the germination
response of vermicompost extract – imbibed seeds was crop species
dependent, though the hypocotyls growth was stimulated by low and
moderate vermicompost extract concentrations. But the radicle growth
was more sensitive to the negative effect of the vermicompost extract. He
Further investigated that both the solid vermicompost and its extract
contain number of active substances of both the phenolic and humic
nature, each with own dose and genotype dependent effect on seed
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germination and early stages of seedling development , especially in pea
and bean.
Hu et al. (2012) have studied the effects of exogenous glucose on
seed germination in wheat seedling under salt stress. In this experiment
the treatments used were 0 and 200 mM NaCl solutions supplemented
with each of four glucose (Glc) concentrations of 0, 0.1, 0.5 and 50 mM.
The results showed that the salt alone significantly inhibited the seed
germination and reduced the seedling growth. Addition of exogenous
glucose in the salt solution attenuated the salt stress effects in a dose–
dependent manner as indicated by enhancement of the growth of radicle.
Glucose addition also showed significant reversal of salt stress in
chlorophyll decay, water loss, dry weight, root length and accumulation
of proline. The glucose-induced salt stress resistance was associated with
enhanced K+ and K+/ Na+ ratio in leaves and activated antioxidant
enzymatic activity, thus decreasing thiobarbituric acid reactive substances
(TBARS & malon-dialdehyde MDA) contents.
Polycyclic aromatic hydrocarbons (PAHs) are one of the persistant
toxic organic pollutants, having a global environmental concern. Seed
germination and early seedling development are the initial handicaps for
the plant establishment in phytoremediation programme. Plant growth
regulators may be potential solutions to these problems. In this regard
Ahammed et al. (2012) have studied the effects of seed treatment with
various concentrations (0.01, 1.0, 100 nM) of epibrassinolide (EBR) in
tomato under graded levels (30, 100, 300  M) of three-ring PAH namely
phenanthrene (PHE) . Delayed and decreased seed germination, reduced
length and fresh weight (FW) of shoot and root were observed following
10 days of PHE exposure in a dose dependent manner. However, seed
treatment with EBR improved the seed germination and increased the
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length and fresh weight of shoot and root. Seed treatment with 1.0nM
EBR was most effective followed by 0.01 nM for the improvement of
germination and seedling growth under the PHE stress in tomato.
Whereas Rehman et al. (2012) have observed the improved growth
and grain yield by seed priming with boron (B) in fine grain aromatic
rice. According to them boron (B) is an important micronutrient required
for rice early seedling growth to the maturity of crop. In their experiment
of priming seeds of fine rice cultivars (Super Basmati and Shaheen
Basmati) were soaked in 0.001 and 0.01% aerated B solutions, while
untreated dry seeds and water soaked (Hydropriming) seeds were taken as
control. Substantial improvement in seedling emergence was noted by
seed priming in 0.001 and 0.01% solutions. Rate of leaf emergence,
elongation and litter appearance were also improved in seedlings raised
from seeds primed in 0.001% B solution in the tested cultivars. At final
harvest all yield contributing parameters were improved by B priming.
Increase in yield was basically due to decreased panicle sterility by B
treatment.
Dong et al. (2012) have studied the thermo-inhibition of lettuce
seed germination. They have also investigated the interaction of nitrate,
abscisic acid (ABA) and gibberellin on seed germination at high
temperatures to understand the mechanism of thermo-inhibition of seed
germination in lettuce (Lactuca sativa L. Jianya “xianteng No.1”). Seed
exhibited notable thermo-inhibition of germination at > 170C in dark and
at > 230C in light. This thermoinhibition of seed germination at 23 or
250C in light was notably decreased by 5 and 10 mM nitrate. The
stimulatory effect was markedly prevented by nitric oxide (NO)
scavenger 2- phenyl 4, 4, 5, 5- tetramethyl imidazol -1 oxyl -3 oxides.
The sensitivity of seed germination to exogenous ABA increased with
14
increasing temperature.
Thermo-inhibition of seed germination was
markedly decreased by fluridone (an inhibitor of ABA biosynthesis) and
GA3, and was increased by diniconazole (an inhibitor of the ABA
catabolizing enzyme ABA 8- hydroxylase) and paclobutrazo (an inhibitor
of GA biosynthetic pathway).
Influence of smoke and heat on seedling emergence from the
germinable soil seed bank of mesic grassland in South Africa has been
studied by Ghebrehiwot et al. (2012). In this study soil seed bank samples
were taken from 0 to 5 cm depth of the topsoil and treated with smoke
water solution, heat and heat with smoke water combine. Subsequent
emergence of seedling was monitored over 90 days. Result showed, total
790 individual, from 11 different plant families. The most abundant plant
family that emerged was Poaceae followed by Asteraceae. Grasses
contributed 18% of the germinable seed bank while nongrass (forbs and
trees) species contributed > 80%. The most abundant grass species that
emerged was Themeda triandra and the most common forb species was
Centella asiatica. And when compared to control, smoke water (SW)
and / or smoke water together with heat (H+SW) treatment resulted in a
1.6 fold increase in mean number of seedling emergence. This treatment
also resulted fourfold to fivefold greater biomass production. Thus the
smoke techniques can be used for the restoration of degraded grasslands
in South Africa and other part of the world.
Soil types, its mechanical and chemical composition along with
available nutrients are the important parameters, affecting the seed
germination, seedling establishment, plant growth and development.
Stephen et al. (2012) have studied the effect of soil physical strength on
root elongation of Eucalyptus todkiana seedlings in mechanically
impeded sandy soils. They have observed that seedling establishment in
15
heavy compact soil is hampered by poor root growth caused by soil
chemical or physical factors.
Researchers have shown their keen interest in recent times, to
substitute the chemical fertilizer with environment-friendly organic
fertilizers. In this regard Aremu et al. (2012) have studied the effect of
smoke water (1:1000, 1:500 and 1:250 dilutions) and vermicompost
leachate (1: 20, 1:10 and 1:5 dilutions)
treatment on the growth of
greenhouse grown bananas. In this experiment, soil drenching (smoke
water and vermicompost leachate and foliar application of smoke water)
was tested on 1- month old tissue cultured banana seedling under green
house conditions. After 3 months, growth parameters such as number,
length of roots and shoots, number of leaves and leaf area and their fresh
and dry weights were analyzed. Vermicompost leachate (1:10 and 1:5
dilutions) significantly increased root length, shoot length, leaf area and
dry weights. Positive effect on rooting is beneficial for acclimatization
and establishment of tissue cultured plantlets.
Recently growth promoting aspect of Ascophyllum nodosum, a
seaweed, and extract on Brassica napus has been studied by Jannin et al.
(2013). In this study the effects of different extracts of brown seaweed
(Ascophyllum nodosum) revealed a significant effect of one of them
(AZAL5) on rapeseeds root (+ 102%) and shoot (+23%) growth.
Stimulation of nitrogen uptake (+21% and +115% in the shoots and roots,
respectively) and assimilation was increased in a similar manner to
growth. Whereas sulfate content (+63% and +133% in shoots and roots,
respectively)
was
more
strongly stimulated
leading
to
sulfate
accumulation. Among the identified genes whose expression was affected
by AZAL5, a plastid division regulator gene, minE was most strongly
affected.
16
Biochemical, molecular and genetic experiments have supported a
central role of sugars in the control of plant metabolism, growth
and
development and have revealed interactions that integrate light, stress
and hormone signaling and co-ordinate carbon and nitrogen metabolism
(Smeekens, 2000). Sugars play a central role in the control of plant
metabolism, growth and development (Coruzzi & Zhou, 2001; Coruzzi &
Bush, 2001; Gazzarrini & Mccourt, 2001). Quirino et al. (2000) have
emphasized that the leaf contents of glucose (Glc) and fructose (Fru)
were shown to increase with leaf age, whereas starch content is
decreased. And a monosaccharide transporter homolog gene, the SEP1
was induced during advance leaf senescence. Developmental stage and
hormones are also vital for senescence. Whereas Ohto et al. (2001) have
reported that floral transition may be controlled positively and negatively,
depending upon sugar concentration, vegetative growth phase and genetic
background by the expression of floral identity genes. Pien et al. (2001)
have investigated a novel marker gene for early leaf development,
indicating the regulation of carbohydrate metabolism with apical
meristem. They have emphasized that sugars can act as morphogens,
providing positional information to the cell cycle machinery and different
developmental programmes, suggesting the involvement of carbohydrate
metabolism in the organogenesis.
Xiao et al. (2000) have studied the role of hexokinase in plant
sugar signaling transduction, growth and development. Their study
reveals a central role of Arabidopsis thaliana hexokinase (AtHXK 1 and
AtHXK 2) in the glucose repressing of photosynthetic genes and early
seedling development. On the basis of the results of the analysis of gene
expression in HXK transgenic plants, there may be three distinct glucose
signal transduction pathways exist in plants. First HXK 1- dependent
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pathway in which gene expression is correlated with AtHXK 1 –
mediated signaling function. Second is glycolysis dependent pathway.
The third is an AtHXK 1 – independent pathway. Investigation of HXK
transgenic Arabidopsis discloses a role of HXK in glucose dependent
growth and senescence. Sugars have been implicated in the control of
plant growth and senescence. Over or under expression of invertases in
transgenic tobacco, tomato and carrot plants could alter sucrose
metabolism, shoot production and senescence.
A genome wide expression profiling study by Mishra et al. (2009)
showed substantial overlap of glc and auxin response pathways
Controlling the root growth and development in Arabidopsis seedlings. In
this study 62% of genes affected by auxin were regulated by glucose
(Glc) and in many instances glucose (Glc) and auxin acted either
antagonistically or synergistically to regulate transcription. While
increased concentration of Glucose induced the genes for auxin
biosynthesis and its transport. A number of auxin regulated genes that did
not respond to glucose alone were modulated by glucose in the presence
of auxin. This includes Aux / IAA and lateral organ boundary (LOB)
gene family members.
The translation of nutrient status to transcriptional regulation
allows the plant to modulate growth both at the whole plant level and
locally, in tissue or cell specific patterns, potentially to co- ordinate
developmental programmes with available carbohydrate as studied by
Ainsworth and Bush (2011). They have studied that in response to sugar
depletion, genes involved in photosynthesis, carbohydrate remobilization
and export and nitrogen metabolism tend to be up regulated. Alternatively
sugar abundance induces typical sink organ activities such as
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carbohydrate import, utilization, storage and starch and anthocyannin
biosynthesis.
Ponnu et al. (2011) have studied the role of Trehalose-6 phosphate,
the precursor of non-reducing disaccharide trehalose as an important
signaling function. Trehalose 6- phosphate signals the availability of
sucrose and then through SnRK1 protein-kinase regulatory system
orchestrates changes in gene expression that enables sucrose to be used in
growth and development. T6P appears also to control qualitative aspects
of growth and development that affect organ formation and function such
as inflorescence, leaf, and tuber and seed development.
Carbohydrates modulate the in vitro growth and branching pattern
of olive (Olea europaea L.) microshoots as studied by Leva et al. (2013)
working with single node microcuttings with two opposite axillary buds,
17, 34,or 68 gL-1 sucrose or mannitol was added to the medium as the
primary carbon source. Shoot development was classified into three
categories namely, an outgrowth of the first bud as an explants ( shoot
type A), an outgrowth
of the
second bud (shoot type B) and an
outgrowth of an axillary bud on either an A – or B – type shoot ( shoot
type C). Explants survival, fresh mass production and pattern of shoot
development were influenced by the type and concentration of sugar
used. Mannitol promoted the sprouting and growth of A-, B-, and C-type
shoots more than sucrose. The results demonstrate that the sugar alcohol
plays an important role in the developmental regulation of olive explants.
Mannitol may also protect against detrimental effects associated with in
vitro growth conditions.
Life can not be completed without proteins both in plants as well as
in animals. Proteins play a vital role, structural, enzymatic and as carrier
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in plants. Lin et al. (1996) have studied the role of cryptochrome-1, a
soluble protein mediating blue-light, dependent regulation of plant
growth and development in Arabidopsis. This protein is expressed in both
young seedlings, grown either in dark or under light and in different
organs of the adult plant. According to them, the over expression of
CRY1 resulted in hypersensitivity to blue, UV-A and green light for the
inhibition of hypocotyls elongation responses. Transgenic plants over
expressing CRY-1 also exhibited a dwarf phenotype with reduced size in
every organ. Thus CRY-1 mediated a light dependent process resulting in
general inhibitory affect on plant growth. This protein (CRY1) is a
photoreceptor mediating blue light dependent regulation of gene
expression in addition to its effect on plant growth.
Reinhold et al. (2011) have studied that in Arabidopsis, there occur
B- amylase proteins (BAMs; enzymes usually associated with starch
break down) present in the nucleus rather than targeted to the chloroplast.
They possess brassinozole resistant 1 (BZR1) - type DNA binding
domains also found in transcriptional factors mediating brassinosteroid
(BR) responses.BZR1-BAMs Controls the plant growth and development
through crosstalk
with BR signaling. BZR1 – BAMs may transmit
metabolic signals by binding a ligand in their BAM domain.
Plastid ribosomal proteins (PRPs) have diverse phenotypic effects
in Arabidopsis as studied by Romani et al. (2012). These ribosomal
proteins control the embryo lethality and vitality including photosynthetic
lesions. These proteins PRPs 20-L1,- L4,- L27 and- L 35 are required
for basal ribosomal activity which become crucial at the globular stage
and during the transition from globular to the
heart stage of
embryogenesis. Lack of any of these PRPs leads to alterations in the cell
division patterns and the embryo development ceases prior to heart stage.
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Spinegourd, a highly nutritious vegetable for its fruit, having
antidiabetic properties and plant of other ethnobotanical importance is a
cash crop for the natives of study area. Perusal of literature reveals that
many aspects of the plant are yet to be investigated. This includes the
suitable status of soil nutrients, seed germination, growth and
developmental aspects of the plant with special reference to sugar and
protein status. Study would help in better cultivation and increased
production.
Present piece of work embodies the detailed study of spinegourd
(Momordica dioica Roxb.ex willd.) for its growth and development. The
following lines of study are considered for this work:
1.
Edaphic factors along three study sites namely kutghan,
Chholeshar and Passon will be studied. This includes mechanical
composition and chemical characteristics of the soil.
2.
Seed output and seed weight (lots of 100 seeds) will be determined.
Seed viability will also be studied.
3.
Seed germination studies will be carried out with and without
scarification. Scarification will be done both by physical method
viz. rubbing with sand paper and chemically with dilute acids and
Gibberellic acid (GA3)
4.
Plants will be raised in earthen pots in replicates. Growth
performance of the plants will be studied after soil amendment in
different doses with animal compost, a seaweed manure and
bonemeal.
5.
For growth and developmental studies, leaf area, relative growth,
net assimilation rate and average fruit yield per plant will be
studied.
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6.
Total sugars including the reducing and non- reducing sugars will
be studied in samples of root, shoot and fruit on different stages of
development from the plants raised in the pots.
7.
Protein content will also be determined in the root,
shoot and
fruits on different stages of development in the samples, taken from
the plants raised in the pots.
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