5. VERMI TECHNOLOGY

5.1 Introduction

Vermitechnology is an important aspect of biotechnology involving the use

of earthworms for processing various types of organic waste into valuable resources

(Lekshmi and Ebenezer, 2011). It is the latest biotechnology which helps in giving

bio-fertilizers in the terms of vermicompost, for agricultural uses and a high quality

protein (earthworm biomass) for supplementing the nutritional energy needs of

animals, at a faster rate. Vermicompost, specifically earthworm casts, are the final

product of vermicomposting. It is an aerobic, bio-oxidation and stabilization of non-

haemophilic process of organic waste decomposition that depends upon earthworms

to fragments, mix and promotes microbial activity (Gunadi; et al., 2002).

Vermicomposting facilities are reported to be already in commercial operation in

Japan, Canada, USA and is also being efficiently practiced in Philippines and in Asia.

Ghosh (2004) reported that vermicomposting at commercial level was started at

Ontario (Canada) only in 1970 and is now processing about 75 tones of refuse per

week.

Vermicomposting as a principle originates from the fact that earthworms in

the process of feeding fragment the substrate thereby increasing its surface area for

further microbial colonization (Chan and Griffiths, 1988). During this process, the

important plant nutrients such as nitrogen, potassium, phosphorus and calcium present

in the feed material are converted through microbial action into forms that are much

more soluble and available to the plants than those in the parent substrate (Ndegwa,

2001). Earthworms are active feeders on organic waste and while utilizing only a

small portion for their body synthesis, they excrete a large part of these consumed

waste material in a half digested form. Since the intestine of earthworms harbour wide

range of microorganisms, enzymes, hormones, etc., these half digested substrate

decomposes rapidly and is transformed into a form of vermicompost with in a short

time (Lavelle, 1988).

This process takes place in the mesosphilic temperature range (35 – 400C).

Earthworms prepare organic manures, through their characteristic functions of

breaking up organic matter and combines it with soil particles. The final product is a

stabilized, well humified, organic fertilizer, with adhesive effects for the soil and

stimulator for plant growth and most suitable for agricultural application. The action

of earthworms in this process is both physical/mechanical and biochemical. Physical

participation in degrading organic substrate results in fragmentation, thereby

increasing the surface area of action turnover and aeration. Biochemical changes in

the degradation of organic matter are carried out through enzymatic digestion, and of

organic and inorganic materials. About 5 – 10 percent of ingested materials is

absorbed into the tissue for their growth and metabolic activity and rest is excreted as

vermicast. The vermicast is mixed with mucus secretion of the gut wall and of the

microbes and transformed into vermicompost (Edwards and Lofty 1972). The

decomposition process continues even after the release of the cast by the

establishment of microorganisms. The studies on the effects of vermicomposting on

one components of organic waste showed that vermicompost enhances degree of

polymerization of humid substances along with a decrease of ammonium N and an

increase of nitrogen (Cegarra, et al., 1992).

The key role of earthworms in decomposing the waste materials and

improving soil fertility is well known since long. (Darwin 1981; Kale et al., 1982)

and the term given to the conversion of biodegradable matter by earthworms into

vermicast. These droppings are high in nutritive value with many micronutrients like

Mn, Fe, Mo, B, Cu, Zn etc. in addition to growth regulators. They are converted into

soluble forms, that can be readily available to crop plants. (Ndegwa and Thompson,

2001; Gajalakshmi and Abbasi, 2004; Benitez et al., 2005 and Suthar, 2006).

Moreover it is rich in several microflora like Azospirillum, Actinomycetes,

Phosphobacillus etc. which multiplies faster through the digestive system of

earthworm (Hussain et al., 2011). It is mixed with the soil and made liquid fertilizer

(Sharma 1997). It influences the physicochemical as well as the biological properties

of soil which in turn improve the fertility (Kadam et al., 2007). Vermicomposting is

an innovative, relatively new alternative technology that makes an eco friendly

environment (Manaf et al., 2009)

Vermicompost looks peat like material with high porosity, aeration, drainage,

water holding capacity and microbial activity (Edwards, 1998; Atiyeh, 2000 d). It

contains most important nutrients in available forms such as nitrates, phosphates,

exchangeable calcium, soluble potassium etc. and has large particulate surface area

that provides man sites for microbial activity and for the strong retention of nutrients.

The plant growth influencing materials i.e. auxins, cytokinins, humid substances etc.,

produced by microorganisms have been reported from vermicompost (Muscolo et al.,

1999; and Selvakumar et al., 2009).

The nutrient status of vermicompost produced with different organic waste is;

organic carbon 9.15 to 17.98 %, total nitrogen 0.5 to 1.5 %, available phosphorus 0.1

to 0.3 % available potassium 0.15, calcium and magnesium 22.70 to 70 mg/100g,

copper 2 to 9.3ppm, zinc 5.7 to 11.5ppm and available sulphur, 128 to 548ppm

(Kale, et al., 1992). Several researchers have compared vermicasts with the

surrounding soils and reported their results (Lavelle, 1978).

Vermiompost is rich in microbial diversity, population, and activity (Subler, et

al., 1998) and vermicast contains enzymes such as proteases, amylases, lipase,

cellulose and chitinase which continue to disintegrate organic matter even after they

have been ejected. The chemical analysis of casts shows 2 times the available

magnesium, 5 times the available nitrogen, 7 times the available phosphorus and 11

times the available potassium compared to the surrounding soil. The vermicompost is

considered as an excellent product that has reduced the level of contaminants and

tends to hold more nutrients over a longer period without impacting the environment.

Being rich in macro and micro-nutrients, the vermicompost, has been found as

an ideal organic manure enhancing biomass production of a number of crops

(Vasudevan, 1997; Hidalgo, 1999). The importance of vermicompost in agriculture,

horticulture, waste management and soil conservation has been reviewed by many

workers (Riggle, and Holmes, 1994; 1995; Kaviraj, 2003).

The growth of plants with vermicompost, influenced the reduction of

bioavailable form of heavy metals and elimination of pathogens (Riggle, 1994).

Vermitechnology stimulates the growth of tea and enhance the soil quality which was

practiced in association with Parry Agro Ltd., in India involving inoculation of

earthworms in trenches with organic inputs in between tea plantations, thereby

increasing the production between 75 and 240% (Kanojia et al., 2001). Earthworms

ingest large amount of soil and are therefore exposed to heavy metals through their

intestine as well as through the skin, therefore concentration of heavy metals from the

soil enter their body (Morgan, 1999). Earthworms may serve as bioindicators of soil

contaminated with pesticides (Saint Denis, 1999), and heavy metals (Spurgeon, 1999

a). Lead, cadmium, zinc and copper are accumulated and, under some environmental

conditions, bioconcentrated in earthworms (Cortet, et al., 1999).

The increased content of K in vermicompost can be attributed largely to gut

transit process (Basker et al., 1993). The action of earthworm Eisenia fetida with

beneficial microorganisms worked upon the substrates and brings the nutrient value

more. But due to the combustion of carbon during respiration (Edwards and Lofty,

1977), the C:N ratio reduced statistically, which is one of the indications of the

biodegradation. The earthworm effect on leaf litter indicate the interplay between

chemical composition of leaf litter and earthworm activity. Earthworm contributed

relatively more to the breakdown of leaves which had a high C:N ratio, lignin and

polyphenol The nitrogen content of vermin compost prepared from water hyacinth

remains high and suitable for the use of agricultural purpose (Lohani 2005).

The organic matter needed for vermicomposting can be obtained from aquatic

weeds which were freely available in freshwater ponds. Vermicomposts produced

with duckweed were characterized by large amounts of dry mass, including organic

carbon and ash. However, these vermicomposts still included less ash than the ones

produced with manure (Gasior et al., 1998) and household organic wastes (Kostecka

et al., 1999), sewage sludge, tannery waste + straw (Mazur et al., 2000), duckweed +

sewage sludge 1:1 (Kaniuczak et al., 2001). In a biological sewage treatment plant,

duckweed acts as a natural sewage treating factor by absorbing nutrients, mainly

nitrogen and phosphorus (Kostecka and Kaniuczak, 2008). The body fluid and excreta

secreted by earthworm (e.g. mucus, high concentration of organic matter, ammonium

and urea) promote microbial growth in vermicomposting. Composting of aquatic

weed biomass was also used for the purpose of vermicomposting with an aid of

Eisenia fetida which is a surface feeding earthworm commonly known as red worm is

very active and potentially useful for management of all types of waste (Tsakamot

and Watanabe, 1977). As described in numerous publications (Baran et al., 1996;

Atiyeh 2000b; Gasior et al., 1998; Zablocki and Kiepas-Kokot 1998; Mazur et al.,

2000; Bury et al., 2001; Kalembasa 2001 Kaniuczak et al., 2001 and Anitha 2002,

the nutrient value of vermicompost is significantly influenced by the origin, type and

proportions of the (mixed) organic wastes utilized.

In the present study a bio-technological approach on aquatic weeds (ie. Trapa

natans, Hygrophila auriculata, Utricularia gibba, Jussiaea repens, Azolla pinnata,

Salvinia molesta, Ceratopteris, thalictroides and Marsilea minuta) using

vermicomposting technique by Eisenia fetida was undertaken and Vigna mungo was

grown in different combination of prepared vermicompost which produced valuable

information.

5.2. Materials and Methods

The selected aquatic macrophytes (Control – T0, Trapa natans-T1, Hygrophila

auriculata – T2, Utricularia gibba - T3, Jussiaea repens – T4, Azolla pinnata - T5,

Salvinia molesta – T6, Ceratopteris thalictroides – T7, Marsilea minuta – T8) were

collected from the experimental perennial ponds of Kanyakumari District and dried

cow dung was also collected. Since the quantity of Azolla pinnata collected was not

sufficient for vermicomposting, it was cultured by sheet method in the Botany

department garden. The earthworm, Eisenia fetida was purchased from Vivekananda

Kendra, Kanyakumari. Earthworms belonged to Phylum-Annelida, Class –

Chaetopoda and Order – Oligochaetae. It occupied a unique position in animal

Kingdom (Sharma, 2003).

Experimental plant : Vigna mungo (L.) Hopper

Systematic position

Class : Dicotyledonae

Sub Class : Polypetalae

Series : Calyciflorae

Order : Rosales

Family : Leguminoseae

Sub – Family : Fabaceae

Genus : Vigna

Species : mungo

Habit : Annual herb, cultivated in Kanyakumari District

Infloresence : Raceme.

Flower : Br. Brl, %, K(5), C(2+2+1), A (9) +1, G(1)

Colour : Bright yellow

Pollination : Self – pollination

Fruit : Legume

Seed : Non-endospermous and with high protein

contents.

Vermibin preparation

Eighteen empty cement tank of size 60cm x 30cm x 30cm were used for the

present experimental work. They were filled with gravel to about 5cms and then with

sand to about 3cms. All the tanks were kept in shade avoiding direct sunlight and

predators like ants, birds, snakes, rats etc. The dried cow dung and water drained

Trapa natans were weighed equally in 2:2 ratios and kept ¾ of the first tank. In the

second tank the above raw materials were prepared in 3:1 ratio. In this way sixteen

tanks were filled with the respective aquatic weeds in 3:1 and 2:2 ratios. The

remaining two empty tanks were filled with cow dung and sand in 3:1 and 2:2 ratios

(without aquatic weeds) as control. The materials took nearly 30 – 40 days for

complete decomposition and gets cooled. After that 100 earthworms (Eisenia fetida )

were introduced in each of the tank including control tanks and the lids were closed

partially. Water was sprinkled every day to maintain the optimum moisture level.

When the compost turns dark brown sweet smelling granules watering was stopped

and on the 45th day the vermicompost is ready for harvesting. (Estherrani et al., 2007;

Uma and Malathi, 2009).

Vermicompost harvesting

The prepared vermicompost (3:1 and 2:2 ratio) from the different experimental

tanks looks dark brown and granular in nature. Alongwith the control vermicompost,

they were used for the experimental works.

Chemical analysis of Vermicompost

From the prepared vermicompost 200 grams were collected from each ratios

and analysed in the laboratory for total nitrogen following Kjeldahl digestion and

distillation method (Bremmer and Mulvancy, 1982). The total available phosphorus

was determined by calorimetric method. (Bansal and Kapoor, 2000). Using flame

Photometer total potassium in the vermicompost samples were determined. The

electrical conductivity and pH were determined by the method of Gary et al., (2006). Zinc,

100xsownseedsofNumber

germinatedseedsofNumberratenGerminatio =

Copper and iron concentrations were also analysed by Atomic Absorption

Spectrophotometry (AAS).

Purchase of Seeds and germination studies

Vigna mungo (L.) Hepper was selected to observe the growth and yield

responses the seeds were purchased from Agriculture College, Coimbatore for the

present experimental works. They were surface sterlized with 0.1% mercuric chloride

solution to make them aseptic and washed with distilled water.

510 seeds were selected and placed in 51 sterilized petridishes (10 seeds in

each petridish) using filler papers. From the prepared vermicompost 1% solution was

made separately and added in each petridish with respect to the ratios 3:1 and 2:2. A

control was maintained only with water. All the setups were in triplicates and kept in

the laboratory to observe the germination percentage on the third day using the

following formula.

Seedling Vigour Index

On the seventh day from each set of germinated seedlings in different ratios

the mean seedling vigour index was calculated in centimeters using the method of

Abdul – Baki and Anderson (1973).

S.V.I. = Mean seedling length in cms x Germination.

Fresh and dry weights

From each setups in different ratios and in control mean seedlings (3 plants)

fresh weight and dry weights were taken using a electronic balance and a hot air oven

and recorded.

100xplant/weightDry

plant/yieldSeedH.I =

Bio-chemical analysis

On the 7th

day total chlorophyll, carotenoid (Arnon, 1949), protein (Lowry et

al., 1951), carbohydrate (Mac Creedy et al., 1950) and lipids (Bligh and Dyer, 1959)

were analysed.

Pot Experiements

Eighteen earthern pots of equal size were selected and filled separately with

3:1 and 2:2 ratios of prepared vermicompost along with sterilized garden soil. (3/4 of

garden soil + ¼ vermicompost). After ten days each of the pot was planted with

seven days old seedlings from the petridishes with respect to the ratios and labelled.

They were kept in triplicates under direct sunlight. Growth characters (21st and 35

st

day) were measured in each ratios of vermicompost applied pots and the mean values

were noted. Bio-chemical analysis like total chlorophyll, carotenoid, carbohydrate,

protein and lipid contents were estimated on the 21st day and 35th day also with

reference to the previous method.

Reproductive studies

Reproductive characters such as number of days required to produce flowers,

number of flowers/plant, number of pods/plant, mean length of pods, number of

seeds/pod, average weight of 100 seeds from each set of experimental plants were

reported and represented in plates, tables and figures respectively.

Harvest Index ( Donald, 1962)

Harvest index (%) was observed using the method of Donald (1962).

Bio Chemical analysis of seeds

Mature seeds were collected from each experimental pots. The influence of

different vermicompost prepared using aquatic weeds in 3:1 and 2:2 ratios on seed

carbohydrate, protein and lipid contents were estimated.

Statistical Analysis

The data obtained from the experimental studies were subjected to mean,

standard deviation and two way ANOVA (Zar, 1974) and the significant level

(P < 0.05) was documented.

5.3 Result

The selected aquatic weeds Trapa natans, Hygrophila auriculata, Utricularia

gibba, Jussiaea repens, Azolla pinnata, Salvinia molesta, Ceratopteris thalictroides

and Marsilea minuta were used for vermicomposting and their chemical characters

like pH, EC, nitrogen, phosphorous potassium, zinc, copper and iron contents in

3:1 and 2:2 ratios were analyzed and the results are given in the followings.

Chemical Composition of Vermicompost

pH

The PH value of the vermicompost in 3:1 ratio ranged from a minimum of 6.7

in Utricularia gibba (T3) used vermicompost to the maximum of 7.4 in T8 plants.

(Marsilea minuta) . But in 2:2 ratio of vermicompost the pH value was

6.4 (Salvinia molesta) in T6 plants and a high value of 7.3 in T1, T5 and

T8 plant. (Trapa, Azolla and Marsilea). In control the values were 7.2 and 7.3,

(3:1 and 2:2 ratios) respectively (Table 5).

Electrical conductivity (EC.ds/m)

The electrical conductivity of the vermicompost remained low (0.93 ds/m) in

3:1 ratio (Trapa natans) and high in Azolla prinnata (1.19 ds/m) used vermicompost.

Whereas control showed 0.73 and 0.90 ds/m of electrical conductance. In 2:2 ratio

of vermicompost T5 plants showed maximum (1.32 ds/m) electrical conductivity.

(Table 5)

Statistical analysis on two way ANOVA (Table 5.11) reported a significant

influence between different vermicompost of aquatic weeds on electrical conductivity

(F= 7.8596; P <0.05).

Micronutrients

The micronutrients of the prepared vermicompost from the selected aquatic

weeds showed higher percentages of nitrogen, phosphorus and potassium (Table 5).

In control vermicompost (3:1) the nitrogen concentration was minimum of 7.5%

whereas it was maximum (14.2%) in Azolla pinnata (T5) used vermicompost. In 2:2

ratio also it showed 14.6% of nitrogen as higher percentage than control. Statistical

analysis on two way ANOVA (Table 5.12) revealed a significant deviation between

ratios (F = 7.6100; P < 0.05) and between different vermicompost (F = 8.7081;

P < 0.05).

The phosphorous content of the vermicompost was analyzed and the results

are shown in Table 5. Among the several aquatic weeds used for vermicomposting in

both the ratios the vermicompost prepared with Azolla pinnata (T5 plants) showed

maximum of 29.4 and 31.3% of phosphorous content than control vermicompost.

Among the eight type of vermicompost prepared, Utricularia gibba (21.5%)

and Salvinia molesta (21.4%) possess minimum percentage of phosphorus in 3:1 and

2:2 ratios.

The potassium concentration among the vermicompost in different ratios

showed minimum of 9.3 and 8.2% in control and maximum of 15.3 and 16.3% of

potassium in the vermicompost of T5 treatment. (Table 5 ). Analysis of two way

ANOVA (Table 5.13) revealed a significant deviation between ratios and between

different vermicompost (F= 8.0446 ; 3.79701 ; P < 0.05).

Elements like zinc, copper and iron contents of the vermicompost were

analyzed and the values are presented in Table 5. The highest value of

138.2 and 147.2 ppm of zinc was observed as maximum concentration in the

Azolla (T5) used vericompost than control (T0). A high value of 41.5, 42.6 ppm

(3:1 and 2.2 ratios) of copper, 873.3 and 894.3 ppm of iron contents were also

observed in Azolla pinnata used vermicompost (T5) against the low values in control

vermicompost. Two way analysis of variance test showed a significant influence

between different vermicompost (F= 23.7162; P < 0.05) alone.

103

Legumes/pulses are considered to be a very important group of plant stuffs

particularly in the developing world, as a cheap source of protein, dietary fibre,

Oligosaccharides, phytochemicals and minerals (Soris et al., 2010). Present study is

carried out in Vigna mungo to find out the yield responses of vermicompost prepared

from eight selected aquatic weeds in two ratios (3:1 and 2:2).

Germination Studies

Germination studies on Vigna mungo was carried out in different ratios of

vermicompost prepared from various aquatic weeds. A wide fluctuation in their

germination percentage on the third day was observed and the results are shown in

Fig. 5.1. The germination resulted 100% in 2.2 ratio (T5) and maximum of 90% in

3:1 ratio of T5 (Azolla pinnala) treatment plants. Whereas control showed 50 and

60% of germination rates in which vermicompost was prepared without aquatic

weeds.

Seedling Vigour Index (SVI)

On the seventh day the seedlings growth was measured and vigour index was

calculated. They are presented in Fig 5.2. It was maximum of 1469.9 and 1863 in

(T5) plants treated with vermicompost of 3:1 and 2:2 ratio than control (T0) plants.

Among the experimental plants used for vermicomposting T8 (Marsilea minuta)

showed minimum seedling vigour index. (538.8-3:1 and 731 – 2:2).

Fresh Weight and Dry Weights

Fresh and dry weights of seven days old seedling were weighed and the mean

values obtained are shown in Fig 5.3. In 3:1 ratio of vermicompost the mean fresh

weight of 0.69 and dry weight of 0.39 gram was observed as maximum in T5 plants.

104

Whereas control plants showed minimum fresh and dry weights (0.38 ± 0.02 and

0.13 ± 0.07). In 2:2 ratio of vermicompost also in T5 treatments the fresh and dry

weights were high.

Morphologial Studies

Growth rates were measured on the 21st day in all the potted plants enriched

with different ratios of vermicompost. Shoot length reached maximum mean value

of 25.7 and 26.4 cm than control in 3:1 and 2:2 ratio of vermicompost (T5) applied

Vigna mungo plants (Table 5.1). On the 35th day growth rates showed variations in

their shoot length (Plates 7-12). In 3:1 ratio the growth rate reached maximum mean

values of 30.7 cm in T5 plants and in 2:2 ratio the growth rate was 31.5 cm as

maximum. In both the ratios of vermicompost applied plants control showed a mean

value of 21 and 20.8 cm respectively (Table 5.1).

Statistical analysis on growth rates in 35th day by two way ANOVA

(Table 5.3) revealed a significant influence of vermicompost between ratios and

treatments. ( F=15.928; 152.51, P < 0.05).

Bio – Chemical Analysis

The bio–chemical analysis on the total chlorophyll content of seedlings in

different ratios of vermicompost applied plant was estimated and the mean values are

shown in Fig 5.4. It was maximum of 1.52 mg/ml, 2.48 mg/ml and 3.5 mg/ml

respectively in T5 treatment of 3:1 ratio and 1.77 mg/g, 2.9 mg/g and 4.23 mg/g in

2:2 ratio of vermicompost applied Vigna mungo plants on the 7th, 21st and 35th days.

In control plants the values observed were minimum of 1.1, 1.77 and 2.63 mg/ml in

the respective ratios.

105

Statistical analysis of two way ANOVA ( Table 5.4) of chlorophyll content on

the 35th

day revealed a significant influence between different ratios and treatments

( F=13.544; 9-84; P < 0.05).

Carotenoid concentration of the leaf tissue was estimated on the 7th

, 21st and

35th

day using standard methods and the results are shown in Fig. 5.5. It was

minimum of 0.246, 0.413 and 0.582 mg/g respectively in the 3:1 ratio of control

plants. The maximum concentration was observed in T5 treatments with 0.337, 0.598

and 0.688 mg/g respectively in 3:1 ratio but in the 2:2 ratio of vermicompost applied

plants the carotenoid contents were higher in the leaves of T5 treatment plants

than control as 0.35, 0.60 and 0.69 mg/g respectively on the 7th, 21st and 35th day

plants (Fig .5.5).

The bio-chemical analysis on protein content from the 7th

, 21st and 35

th days

were estimated and the mean values are presented in Fig. 5.6. In 3:1 ratio of

vermicompost in Vigna mungo the highest amount of protein was (5.30, 7.40 and

9.50 mg/g) observed on the 7th, 21st and 35th day plants. Likewise the amount of

proteins were also maximum in the 2:2 ratio as 5.40, 7.70 and 9.80 mg/g respectively

in the T5 treatment plant. Control plants produced a minimum mean value of 4.20,

5.40 and 7.60 mg/g protein concentrations in their leaves. In 2:2 ratio of

vermicompost applied Vigna mungo also minimum amount of protein contents were

observed (4.0, 4.90 and 7.20 mg/g) in control.

Statistical analysis of two way ANOVA (Table.5.6) revealed a significant

influence of vermicompost between treatments (F = 10.4707; P < 0.05) and between

ratios (F = 6.896; 27.560; P < 0.05) on protein content.

106

The amount of carbohydrate from the 7th

, 21st and 35

th day plants were

estimated and the mean values are shown in Fig ….. It was noted minimum of 2.04,

4.15 and 6.03 mg/g of carbohydrate content in 3:1 ratio of control plant. Whereas

among the various aquatic weeds used for vermicomposting, Azolla used treatment

(T5) produced maximum of 4.82, 6.74 and 8.71 mg/g of carbohydrate content in the

respective days. In 2:2 ratio of vermicompost applied Vigna mungo the maximum

rate of 5.25, 6.84 and 9.0 mg/g of carbohydrate was observed against the minimum of

2.02, 4.09 and 6.0 mg/g respectively in control. (Fig . 5.7).

Statistical analysis of two way ANOVA on carbohydrate content (Table 5.7)

reported a significant deviation between ratios and treatments.(F=19.899; 133.85;

P<0.05).

Reproductive Studies (From 38 – 63 days)

Reproductive character such as flowering days, number of flowers/plant,

number of pods/plant, mean length of pods, mean number of seeds/plant etc were

studied in each treatment and the results are shown in Table 5.2.

Flowering

Flowers were was dark yellow in colour and the blooming days varied in each

treatment and started from the 37th

day onwards. In 3:1 ratio of vermicompost applied

plants flowering was earlier (38 ± 1) in T5 treatment than control (43 ± 1.0). In 2:2

ratio of vermicompost applied plants the flowering days started from 37 to 41 days

and in T5 treatment earlier flowering was observed (37th day). Whereas control plants

produced flowers from the 42nd day onwards (Table 5.8 ). Maximum number (25.33

107

± 3.06 and 34.32 ± 2.07) of flowers were noticed in the T5 treatment which were

applied with 3:1 and 2:2 ratios of vermicompost.

Number of Pods

The number of pods in the different treatments of vermicompost applied

Vigna mungo was observed and the results are shown in Fig. 5.8 and 5.92; Plate 13 and

14. The pod production reached maximum mean number (28 ± 2.0 and 33.0 ± 2.9) in T5

treatment of the two ratios of vermicompost used plants than control (17.33 ± 3.06

and 19.30 ± 3.10).

Pod Length

The pod length of Vigna mungo varied in each treatment from a minimum

length of 3.6 ± 0.10 cm to a maximum of 6.2 ± 0.18 cm in 3:1 ratio of T5 treatment

plants. In 2:2 ratio a low length of 3.5 ± 0.10 cm was observed in T0 treatment

against a high length of 6.4 ± 0.12 cm in T5 treatment plants.

Seeds/Pod

The total number (mean ± SD) of seeds /pod was counted and shown in Table

5.2. The number ranged from a minimum mean value of 5 ± 1 in control to a

maximum of 6.33 ± 0.58 in 3:1 ratio ( T5) and from a minimum of 5.0 ± 1.0 in control

to a maximum of 7.00 ± 0.1 in 2:2 ratio of vermicompost applied Vigna mungo plants.

Seeds / Plant

In all the different vermicompost applied Vigna mungo plants the total number

of seeds produced / per plant was collected and the results are shown in Table 5.2. It

was noticed a minimum of 69.66 ± 17.62 seeds in control plant against a maximum of

108

200.33 ± 21.39 seeds in 3:1 ratio and 61 ± 14.74 in control plants against 204 ± 24.00

seeds of 2:2 ratio in the vermicompost of Azolla applied plants.

Harvest of Seeds

From each set of experimental plants 100 seeds were collected from the

first harvest and their average weight was observed and shown in Fig . 5.12. It was a

minimum of 4.08 ± 0.18 and 4.14 ± 0.04 grams in control (3:1 and 2:2 ratios). A

mean weight of 5.18 ± 0.12 and 5.21 ± 0.03 grams in T5 treatment of the seeds were

noticed in the two ratios of the vermicompost applied Vigna mungo plants.

Harvest Index

Harvest index (%) was calculated from each set and shown in Fig. 5.13. In

the verimcompost applied Vigna mungo harvest index was maximum of 40.96% and

42.46% in 3:1 and 2:2 ratio respectively than control (26.18 and 26.27%).

Bio–chemical analysis of the mature dry seed were harvested and the amount

of carbohydrate, protein and lipid contents were estimated and shown in Fig . 5.13.

Seed Protein

In 3:1 ratio of vermicompost applied Vigna mungo the seeds protein

(mean ± SD) was high in T5 treatment as 117.0 mg/g whereas in control 85.87 mg/g

was observed. It occurs in the descending order as T5 > T6 > T8 > T2 > T7 > T4 > T3 > T1

respectively. In 2:2 ratio an increasing trend was observed as To < T3 < T1 < T7 < T4

< T8 < T6 < T5 respectively. The minimum of 87.1 mg/g was observed in control

against the maximum of 117 mg/g in the T5 treatment (Fig. 5.1 and 5.11).

Two way Analysis of variance test (Table 5.8) between different ratios of

vermicompost and treatments revealed a significant influence (F = 19.20; 42.09; P < 0.05).

Seed Carbohydrate

The total carbohydrate content (mean ± SD) of the seeds obtained from

different treatment were analyzed and the results on their mean values are shown in

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Fig 5.10 and 5.11. In 3:1 and 2:2 ratios of vermicompost in different treatments given

to Vigna mungo plants a maximum of 27.45 and 28.33 mg/g of carbohydrate contents

were observed as maximum concentration and a minimum of 15.09 and 16.03 mg/g

was noticed in the seeds of control plants.

Statistical analysis of two way ANOVA (Table 5.9) between different ratios of

vermicompost and treatments showed a significant influence at P < 0.05 level

(F=14.36 and 34.43; P < 0.05).

Lipid Content

The lipid content of the seeds were estimated using standard procedure and the

results are shown in Fig . 5.10 and 5.11. It revealed higher concentration in T5

treatment as 8.97 and 10.05 mg/g of 3:1 and 2:2 ratio of vermicompost applied Vigna

mungo. In control treatments 4.19 and 4.12 mg/g of lipid contents were recorded as

minimum concentrations.

Analysis of two way ANOVA (Table 5.10) test showed statistically significant

influence of different ratios and treatments on lipid content of the seeds [F= 21.50;

33.93; P < 0.05].

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5.4 Discussion

Long term application of inorganic fertilizers like ammonium sulfate and

sulfur coated urea has led to soil acidification (Ma et al., 1990), decreases soil

stability, (Estevez et al., 1996), aeration (Sharma, 2003) and earthworm population

(Edwards and Bohlen, 1996). Vermicomposting is an important aspect of

biotechnology involving the use of earthworm for processing various type of wastes

into valuable resource. Thus vermicompost is used successfully to clear the

environment, (Lal et al., 2003) improve the soil texture, porosity and aeration

(Kannan, et al., 2011). It increases total and available nitrogen, phosphorous,

potassium, micronutrients, microbial population, enzyme activities and growth

regulators which produce beneficial effect on the growth of a variety of plants.

(Chaoui et al., 2003 and Deng et al., 2004). In general vermicompost was prepared

utilizing organic waste, sugar mill waste, (Parthasarathi et al., 2008), leaf litter

(Shanthi and Kurian, 2010), agro-industrial waste (Khan et al., 2009), cow dung

(Hatti et al., 2010), domestic waste (Estherrani et al., 2007) and bio-gas slurry

(Vijaya, 2010). Several aquatic macrophytes were also utilized in vermicomposting.

Members like Eichhornia crassipes, Lemna minor, Typha angustata, Pistia stratiotes,

Nymphaea stellata, Hydrilla verticillata etc. were used for vermicomposting with the

help of Eisenia fetida and Perionyx excavatus earthworms (Kostecke and Blazej,

2000; Sannigrahi 2009). In the present study among the 55 weeds observed (Table 1)

eight dominant weeds of the experimental ponds (Trapa natans, Hygrophila

auriculata,Ceratopteris thallictroides, Utricularia gibba, Jussiaea repens, Azolla

pinnata, Salvinia molesta and Marsilea minuta) were choosen for vermicomposting

with Eisenia fetida earthworms in 3:1 and 2:2 ratios. The results observed on

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vermicompost showed a rich chemical constituents (Table 5) in their physical and

chemical characters.

pH of the vermicompost

The pH value of the vermicompost ranged from a minimum of 6.4 in Salvinia

molesta to a maximum of 7.4 in Marsilea minuta used vermicompost. Similar

findings were made by Kitturmath et al. (2007), Alikhan et al. (2009) and Nath et al.

(2009). The vermicompost prepared using Typha angustata showed a pH value of

6.17 and Pistia stratiotes with pH 6.07 (Sanigrahi, 2009). The duckweed (Lemna

minor) vermicompost showed lower pH value than those of manure vermicomposts

(Coster et al., 1998) and household organic waste (Kostecka et al., 1999; Garg and

Kaushik, 2004). Pig vermicompost with and other wastes used vermicompost showed

the pH value of 5.3 (Nogales et al., 1999). The lower pH was attributed to the

mineralization of nitrogen and orthophosphate bio-conversion into intermediate

species of organic acids (Ndegwa et al., 2000). Excess water leads to anaerobic

conditions which in turn lower the pH and create acidic condition. The higher pH

value reported from bio-gas slurry used vermicompost was ranged from 7 to 7.5. The

mean pH of water hyacinth used vermicompost was 7.7 (Shrestha and Tamrakar,

2010) and municipal solid waste used vermicompost showed a pH of 8.6 (Kasthuri et

al., 2011). Estherani et al. (2007) observed a pH value of 7.8 in leaf litter used

vermicompost. Food waste vermicompost and compost had the pH which ranged

between 6.8 to 8.1. (Atiyeh et al., 2000). The present observation of pH in the

prepared vermicompost showed a close link with the above findings and the pH range

between 6-7 seems to promote the availability of plant nutrients (Edwards and

Bohlen, 1996; Gunadi and Edwards 2003).

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Electrical Condutvitity (EC)

Electrical conductivity of the prepared vermicompost of the present

investigation was lower in control (0.73 ds/m) and higher as 1.32 ds/m in Azolla used

vermicompost (Table 5). The decreased EC could be due to the increased

permeability leading to leaching of salts. (Parthasarathi et al., 2008). Similar to the

present observation increased value of EC was reported by Kasthuri et al. (2011) and

Nath et al. (2009). The electrical conductivity of different agro-industrial waste (coir-

waste) ranged from 0.76 ds/m to 1.15 ds/m. (Kitturmath et al., 2007). The main cause

of increased EC might be due to the loss of weight of organic matter and release of

different mineral salts in available form (Kaviraj and Sharma; 2003 and Wang et al.,

2007).

Micronutrients of the vermicompost

Nitrogen

Micronutrients are essential elements and for the compatible agriculture use the total

level of nitrogen content should be less than 0.6% (Zueconi and Bertold, 1991);

Parthasarathi and Renganathan, 1999). Nitrogen is the basic constituent of protein,

nucleic acid, vitamins and other organic molecules. In the present observation the

nitrogen content ranged from a minimum of 7.5% (control) to the maximum of

14.2%, (3:1 ratio) and (2:2 ratio) 14.6% in the vermicompost of Azolla pinnata

(Table 5). Wong et al, (1997) observed high amount of nitrogen and phosphorus in

fresh duckweed plants than sewage sludge used vermicompost (Bury et al., 2001).

Animal, agro and kitchen wastes used vermicompost showed an increased nitrogen

content which ranged between 8.0 ± 0.06 and 26.9 ± 0.08 in the vermbed because of

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mineralization of organic matter (Hand et al., 1988). Eisenia fetida in cowdung slurry

increased the nitrate nitrogen content and losses of organic carbon might be

responsible for nitrogen addition in the form of mucus, nitrogenous excretory

substances, growth stimulatory hormones and enzymes from the gut of earthworms.

(Tripathi and Bhardwai, 2004). Water hyacinth showed 1.36% of nitrogen (Hoflmann

et al.,, 2004). Depending upon the chemical composition of aquatic weeds and the

turbidity of water bodies in which they grow the quality of vermicompost differs.

(Anon, 1976). Kannan et al. (2011) reported higher amount of nitrogen content,

which is two times greater than cowdung when he used black gram pod, waste and

cowdung for vermicomposting preparation. The higher rates of vermicompost in the

present investigation is in accordance with the observation of Vasanthi and

Kumaraswamy (1999). It was mainly due to the release of nitrogenous products of

earthworm metabolism through the cast and mucoproteins as evidenced by

Padmavathiamma et al. (2008).

The nutrient composition and physico-chemical parameters of vermicompost

are subjected to the activity of earthworms in their food substances (Zanin et al.,

1988; Shrestha and Tamrakar, 2010). While mineralization of waste is accelerated by

passing the ingested food through the gut of earthworms (Julka 2001), thus stabilizing

the NPK contents (Karmegum and Daniel, 2000) to plants in available form. In the

present investigation the phosphorus content of the vermicompost in 3:1 ratio of

different aquatic weeds ranged from 19.2% (control) to 29.4% and from 20%

(control) to 31.3% in 2:2 ratio of Azolla used vermicompost. The high of phosphorus

in the vermicompost of Agro-industrial waste and paper waste sludge after worm

activity showed an increase of 25% in total phosphorus which was mainly due to the

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microorganisms present in the casts (Satchell and Martin, 1984) and the reports are in

line with the present observation. It was also proved by Graff (1981) that addition of

earthworms in the soil enriches the phosphorus content. Sarojini et al. (2009)

observed higher percentages of phosphorus content which was mainly due to the

addition of more cowdung during vermicomposting with nutrients for better quality.

Potassium concentration in all the prepared vermicompost was analysed and

the results are shown in Table 5. The values ranged from a minimum of 8.2% in

control (2:2 ratio) to the maximum of 16.3% in Azolla (T5) used vermicompost. In

municipal solid waste, Eichhonia crassipes, leaf litters used vermicomposts the

percentage contribution of potassium was low (Kasthuri et al., 2011 and Estherrani,

2007). In Agro-industrial waste used vermicompost 35% of potassium was noticed.

(Kitturmath et al., 2007; Chakrabarty et al., 2009) have reported higher content of

Potassium in the sewage sledge used vermicompost. Kaviraj and Sharma (2003)

observed that the total potassium was increased upto 16% by Eisenia fetida and 5%

by Lampita maturitii during vermicomposting. Suther (2007 and 2007a) suggested

that earthworm processed waste material contained high concentration of

exchangeable K due to its enhanced microbial activity during vermicomposting

process which consequently increased the rate of mineralization. Moreover in the

present observation, statistical analysis on two way ANOVA test revealed the

significant influence of various aquatic weeds on vermicomposting at P < 0.05 level.

The vermicompost prepared from organic waste has been analysed and

showed 120.5 ppm of nitrogen, 18.39 ppm of phosphorus and 50.90 ppm of potassium

(Uma and Malathi, 2009). Fredrickson et al. (2007) also observed higher NPK values

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and these parameter depends on the characteristics of each process. Jackson, (1973)

reported that the availability of higher nutrients and good medium for multiplication

of microbes may increase the NPK content of the vermicompost and it is evidenced in

the present study with different feeding material. Researchers like Lohani (2005).

Rakshit et al. (2008) and Ansari (2009) has reported the efficiency of vermicompost

prepared from aquatic weeds had produced valuable nutrient rich manure.

In the present study zinc, copper and iron concentrations were analyzed from

the vermicompost of different aquatic weeds and the reports are presented in the Table 5.

The zinc content of the vermicompost was minimum of 110 ppm and 112.1 ppm

respectively in control with the maximum of 139.9 ppm in Jussieae repens (3:1 ratio)

and 147.2 ppm in Azolla pinnata (2:2 ratio). Higher levels of zinc was observed in all

the remaining vermicompost also (Table 5). The present findings are in agreement

with the reports of Jeyabal and Kuppusamy (1997). Vermicompost of paddy straw

and groundnut shell showed 245.2 ppm of zinc concentration. Kitturmath et al.

(2007), Suther, 2007; Kostecka and Kaniuezak (2008) observed that Duckweed with

cow dung mixed vermicompost contained more zinc, copper, nickel, chromium,

cadmium and lead. It was found with less iron and magnesium contents.

Copper forms an essential component of enzymes like phenolases and

tyrorinase. It helps to maintain the carbohydrate-nitrogen balance. In the present

observation the observed values ranged from 22.7 ppm (T1) to 42.6 ppm (T5). Similar

findings were reported by Kitturmath et al. (2007).

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Similar to copper, the iron concentration of the present investigation in the

different vermicompost showed variations (Table 5). Control showed 664.3 ppm of

iron content as minimum and maximum of 894.3 ppm was noticed in T5 treatment.

The present finding corroborate with the results of Muthukumarasamy (1997).

Several researches reported the nutrient composition of vermicompost varied in their

micronutrient levels depending upon the waste materials used during the feeding

process of earthworms and its effect is favourable to crop plants (Suther, 2006; Paola

and Ceppi, 2008). Selvakumar et al. (2009) observed lower concentrations of Cu, Fe,

Pb and Zn in the vermicompost prepared with Azadiracta indica and Parthenium

hysterophorus leaves.

In general vermicompost prepared from animal dung is universally believed to

be beneficial to soil and plants and there are few reports giving evidence that the same

may be true of vermicompost generated from other sources. To explore this area

present work is carried out in the impact of eight aquatic weed vermicompost (T1 –

T8) on Vigna mungo. Plants like Abelmoschus esculentum, Solanum melongena,

Cyamopsis tetragonaloba, Crossandra undulufolra were treated with water hyacinth

vermicompost (Gajalakshmi and Abbasi, 2004). As pulses are high in nutrient levels

present work is carried out to apply the vermicompost prepared from the selected

eight aquatic weeds in 3:1 and 2:2 ratios to Vigna mungo a common pulse used by the

people of Kanyakumari district. It is an economically important annual summer crop

termed commonly as ‘black gram’. It occupies the third position and a highly priced

pulse of India and it is native to Central Asia. (Gaur and Gaur, 2010; Hussain, 2011).

The seeds are rich in protein, potassium, sodium, calcium, phosphorus and vitamins

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along with medicinal properties like curing diabeties, nervous and digestive disorders

and rhomatic afflictions.

Application of vermicompost in the present study accelerates maximum

percentage and earlier germination in T5 ( Azolla pinnata) plants than control (T0).

All the seed germinated earlier on the third day than control and the results are shown

in Fig 5.1. Previous reports on Cucurbita pepo (Mary, 2007) and Sorghum bicolor

(Johnsy, 2005) when treated with Azolla extracts have shown earlier and maximum

parentage of germination. Chauhan et al. (2010) also pointed out the effects of

vermicompost on faster germination of Pisum seeds. Nithya and Thangaraj (2010)

noticed in Chenopodium album, when applied with vermicompost maximum

percentage of germination was noticed though the time taken was little more. In

general germination improves the nutritive value of cereals and legumes and

minimize the level of utilizable nutrients. During the process metabolic enzymes are

activated ( Onwuka et al., 2009; Maneemegalai and Nandakumar, 2011).

Seedling vigour index of Vigna mungo on the 7th day was studied in all the

treatments and shown in Fig 5.2 which revealed maximum SVI was reported in T5

treatment than control. Similar observations were noticed in Phaseolus aureus when

supplemented with bio-compost (Alikhan et al., 2009).

Morphological growth rate of seedlongs grown in different (3:1 and 2:2 ratios)

vermicomposts were observed on the 7th, 21st and 35th day after germination. Shoot

length reached maximum in the T5 treatment plants than the remaining treatments. It

was a mean value of 30.7 ± 0.14 and 31.5 ± 0.12 cms on the 35th day. The use of

Azolla pinnata was beneficial to the crops by its growth stimulating compounds

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produced by the endosymbiotic cyanobacteria which was released in the soil by

living cells or lysis or after death. Better vegetative growth was reported earlier by

the application of Azolla to rice plant. In the present investigation Azolla was used

in vermitechnology which increased the shoot growth similar to the vermicompost

prepared from other sources. Seedling growth with vermicompost was characterized

by better performance in terms of growth rate and final weight. Sivakumar et al.

(2008) reported 100% of germination, increased shoot length of Vigna radiata which

was applied with vermicompost prepared in combination with Neem leaves,

Parthenium and cow dung. In a horticultural crop (Marigold) application of 10%,

20% and 100% pig waste used vermicompost, fresh, and dry weight increased than

compost.

In Tomato increased growth rate was reported and in Raspberry 1.8

times of increased growth rate was noticed (Atiyehi et al., 2000). Vermicomposting

is comprised with large amount of humic substances, some of the effects

of which on plant growth are similar to those of soil applied with plant growth

regulators (Muscolo et al., 1999). The observed fresh and dry weights of the present

investigation also showed similarity with the earlier reports of Shanthi and Kurian

(2010) in Arachis hypogea plant. The difference in the vegetative growth

was also due to the variation in pH and also by the composition of

nutrients in the vermicompost. In the present study by using different aquatic weeds

the vermicompost was prepared and it stimulate the growth rates of

Vigna mungo and the variation of pH was 6.4 to 7.3. Moreover

nitrogen and phosphate concentration had a great influence on vegetative,

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growth (Kale et al., 1992). Ground nut haulm used vermicompost produced rapid

plant growth as they were rich in nitrogen content (Ansari, 2008).

The total chlorophyll and carotenoid contents were estimated in the 7th, 21st

and 35th

days in 3:1 and 2:2 ratio of vermicompost applied Vigna mungo plants.

Maximum of 3.5 and 4.23 mg/g of chlorophyll contents were noticed in T5 treatment

than control. Uma and Malathi (2009) observed maximum chlorophyll a, b, total

chlorophyll and carotenoid contents in Amaranthus species Atiyeh et al. (2000)

reported, 10-20% application of pig waste used vermicompost on Marigold has

increased the chlorophyll content of leaves. Similar findings were noticed in Vigna

mungo when treated with bio fertilizers (Sivakumar et al., 2009). Statistical analysis

on chlorophyll and carotenoid content of different treatments showed significant

influence of vermicompost (P < 0.05 level).

The observation of protein and carbohydrate content of Vigna mungo showed

maximum level in the vermicompost applied plants than control. But the

vermicompost prepared with Azolla pinnata ( T5 treatment) influence maximum

level of protein (9.80 mg/g) and carbohydrate (8.7 mg/g) in 2:2 ratio of

vermicompost. An increased total carbohydrate content in okra grown with

vermicompost over chemical fertilizer and control (Ismail, 1983). In green gram

Kasthuri et al. (2011) observed an increase of total chlorophyll, carbohydrate, protein

and amino acid contents by the application of vermicompost. In general addition of

vermicompost to soil resulted an increase in the mineral contents like Ca, Mg, P, Mn

and Zn which indirectly influence the growth rates in red clover and Cucumber (Sainz

et al., 1998). For better growth of plants vermicompost application was reported as

an appropriate medium (Nithya and Thangaraj, 2010).

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There are several reports regarding the application of vermicompost on cereals

and pulses that favours vegetative growth, flowering and yield. Vermicompost

obtained form Eichhornia crassipes significantly enhanced the growth rates and

flowering of Crossandra undulaefolia than control treatments (Gajalakshmi and

Abbasi, 2002). Similarly in strawberry application of vermicompost increased plant

growth and yield significantly including an increase upto 35% in leaf area, 37% in

total biomass, 40% flower number and 35% marketable fruit weight (Aracnon et al.,

2004). In pulses Javaid (2009) Sinha et al., (2010) has pointed out that vermicompost

is a superior treatment of enhancing significant positive effect on nodule formation,

flower number and pod production. In the present study earlier flowering (37th

day

onwards) maximum number of flower, pod production, number of seeds etc. were

more in the vermicompost applied (Azolla pinnata) Vigna mungo (Table 5.2). The

present observation coincides with the earlier reports of better growth, yield and

quantity of black gram and Cow Pea when applied with vermicompost of organic

waste along with NPK (Parthasarathi et al., 2008; Kumari and Ushakumari, 2002).

Flower production increased in Petunia when treated with 40% of vermicompost

(Chamani et al., 2008) and in Cow Peas treatment of vermicompost with NPK

influenced the pod production and significantly the yield/hectare (Chauhan et al.,

2010). The growth parameters on Capsicum annum such as shoot and root length of

seedlings, internodel length, number of leaves, yield, earlier germination of seeds

were observed when it was enriched with Azolla extracts added vermicompost. In

the present study number of pods, number of seeds and pod length reached maximum

in T5 treatment. Kumar (2007) observed a mean of 36.53 pods in a legume.

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In the present observation harvest index reached maximum (42.46%) in 2:2

ratio of T5 treatment than control (21.82%) and in Cajanus cajan, Vanaja et al.,

(2010) observed 38.2% of Harvest index. Hussain et al. (2010) reported a maximum

of 35.66% of Harvest Index when Vigna mungo was treated with bio-fertilizers. The

increase in HI was due to its improved pod set and seed yield with the nutritional

enrichment of Azolla used vermicompost. The nutritional values of lipid, carbohydrate

and protein were analyzed from the seeds and shown in Fig 5.11. It was reported that

higher amount of protein, moderate amount of carbohydrate and minimum quantity of

lipid was observed. Maximum amount of protein (Table 5.10 and 5.11) was recorded

in all the treatments and it was maximum (117mg/g) in the vermicompost of T5

treatment which was prepared by 2:2 ratio of Azolla and cowdung.

The nutritional value of black gram seeds also includes crude fibre, calcium,

magnesium, iron, zinc, vitamin A, thiamine, riboflavin, niacin, vitamin B, folate and

ascorbic acid. The pod walls are fed to cattle. Flour from the seed is used as a

substitute for soap; it makes the skin soft and smooth in traditional medicine, the seed

is used for its supportive, cooling and astringent properties. (Soris et al., 2010).

Vermicompost prepared from different aquatic weeds are efficient like other

waste used vermicompost in their physical, chemical and biological characters Azolla

pinnata the free floating aquatic fern have high nutrient value and enclosed the

nitrogen fixing blue green algae (Anabaena) in their leaves. When it was used for

vermicompostiong the nutrient levels of high NPK, organic carbon along with

micronutrients reached maximum level. Eisenia fetida is also a good decomposer

(Karmagam and Daniel, 2000) and helps to produce better vegetative growth, earlier

flowering and high yield in Vigna mungo.

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Aracnon et al. (2006) reported that enhanced availability of plant growth

influencing substances produced by microorganisms in vermicompost were factors

considered to have contributed to increased fruit yield in peppers. These findings

support our observations that vermicompost significantly enhanced the growth of the

plants and also increases the microbial diversity of vermicompost applied soil.

In conclusion the present study reports the utilization of aquatic waste weeds

in vermicomposing and by vermitechnology the unwanted weeds can be managed and

converted into a new, useful, valuable manures. Moreover the vermicompost

prepared from the experimental weeds has been proved as the cheapest source of

nitrogen and applied to other crops also as an ecofriendly biomanure without any

expense and pollution. It also helps to increase the micro flora of the soil and save the

environment from adverse effects.