Part V. Utilizability of compost/ Vermicompost

Transcription

1 Part V Utilizability of compost/ Vermicompost

2 Assessment of impact of vermicast generated from reactors fed with water hyacinth neem leaves on plant growth Whereas vermicast generated from animal dung is universally believed to be beneficial to soil and plants, there are no reports giving evidence that the same may be true of vermicasts generated from other sources. During the efforts to involve villagers in vermicomposting (described in Part V of the thesis and also in Gajalakshmi and Abbasi, 2002), several farmers expressed reservations about using water hyacinth vermicast as fertilizer, conveying the fear that the vermicast may be harmful to the plants. Hence, in order to assess whether such apprehensions are reasonable, we have conducted two types of experiments; (a) Qualitative studies were done on vegetable plants at the kitchen garden of five farmers. (b) Controlled experiments were conducted on an ornamental flowering plant. This study is detailed in chapter 16 and is due to appear in Bioresource Technology. Chapter 17 deals with neem leaf litter. n recent years, neem has attracted global attention due to its potential as a source of natural drugs as also environment-friendly pesticides (Agarwal, 1996). With this in view, neem leaves were explored as a substrate for generating vermicompost. The use of the neem vermicompost as fertilizer-cum-pesticide was also explored with respect to its impact on the growth of a common vegetable plant. The study is due to be published in Environmental Technology.

3 References Agarwal,A., What's in a neern? Down to Earth 14 {20), Gajalakshrni, S., and Abbasi, S.A., Effect of the application of water hyacinth cornposuverrnicornpost on the growth and flowering of Crossandra undulaefolia, and on several vegetables. Bioresource Technology, in press.

4 Chapter 16 Effect of the application of water hyacinth compostlvermicompost on the growth and flowering of Crossandra undulaefolia, and on several vegetables* S. Gajalakshmi and S.A. Abbasi Centre for Pollution Control & Energy Technology Pondicherry University, Kalapet, Pondicherry , NDA Abstract The impact of the application of compost~vermicompost obtained from water hyacinth (Eichhornia crassipes, Mart. Solms) on plants was assessed in terms of growth and flowering of the angiosperm crossandra (Crossandra undulaefolia) Overall nine morphological, size, and yield attributes were studied in crossandra saplings raised on water hyacinth compost or vermicompost as compared to the untreated saplings. The studies reveal that application of vermicompost led to statistically significant improvement in the growth and flowering of crossandra compared to the untreated plants. The impact of compost was also beneficial but a little less distinct than the positive impact of vermicompost. Qualitative studies were simultaneously conducted in five kitchen gardens owned by farmers near Pondicherry. n three of these locations water hyacinth vermicompost was applied - and no other fertilizer - for months to different species of vegetables. Water hyacinth compost was similarly applied in another two locations. n all the locations no adverse effect on any of the plant species was observed. We believe these studies would help in dispelling the apprehension of farmers that compost vermicompost obtained form a pernicious weed like water hyacinth may have deleterious effect on other plants. * Pre-print of the paper due to be published in Bioresource Technology

5 1, ntroduction We have been studying various aspects of composting and vermicomposting of water hyacinth with emphasis on developing more efficient, hence more economically attractive, systems for the utilization of water hyacinth than available hitherto (Gajalakshmi et al 2001 a, b, c). We have also made attempts to attract marginal farmers towards utilizing water hyacinth in this manner (Rajalingam 2001). During such attempts apprehensions were raised by the farmers that compost or vermicompost obtained from water hyacinth -which is a pernicious weed, widely perceived as a scourge of farmers - may be harmful to the plant growth. The fear was widespread and threatened to saboutage the author's attempts of developing a method of utilizing water hyacinth beneficial to the farmers. Hence, in order to decide whether such apprehensions are reasonable we have conducted two types of experiments: Qualitative studies were done at the kitchen gardens of five farmers. n each location - 4 m2 plots were marked out and the following common vegetables were planted : lady's finger (Hibiscus esculentus), brinjal (Solanurn melongena), cluster bean (Cyamopsis tetragonoloba), chilli (Capsicum annum), and tomato (Lycopersicon esculentum). Three of the plots were treated with water hyacinth vermicompost and two of the plots with equal quantity of water hyacinth compost. As these were qualitative studies basically to see whether the water hyacinth compost vermicompost discourages plant growth, no controls of unfertilized plots were studied. Controlled experiments with and without fertilization with the water hyacinth compost vermicompost were conducted on the saplings of Crossandra unduleefolia, an angiosperm and a free-branching perennial herb ( Pandey, 1982 ). t is an ornamental plant, and is marketed as such. Crossandra is often grown to beautify kitchen gardens as it is small in size and sports attractive flowers. This species was chosen for the study for three reasons: it is well established in the area where the authors work; it is fast growing; and it flowers early and profusely.

6 Whereas the first set of experiments were qualitative, the second set aimed to quantify the impact of water hyacinth compost vermicompost. 2. Methods 2.1. General All quantities mentioned below represent dry (oven dried at 105'C to constant) weights unless otherwise stated. Water hyacinth was composted and vermicomposted as detailed earlier ( Gajalakshmi et al, 2002 ) Controlled experiments with C.undulaefolia Ten day old saplings of C.undulaefolia (height 7.4 * 0.8 cm), raised in the nursery of Pondicherry University, were transplanted in 8 litre cement pots. Three sets of 15 pots each were employed for this purpose. The first set had 4 kg soil mixed with 2 kg water hyacinth compost; the second set had 4 kg soil blended with 2 kg vermicornpost, and the third set, to serve as controls had only 6 kg soil. All pots were uniformly irrigated once a day. The plants were observed daily for plant height, number of leaves, root length, days to first flowering, number of flowers, and length of the inflorescence. Plant biomass, root : shoot ratio (by weight), and harvest index - were studied on the 90h and the 180'~ day of the experiment by sacrificing 5 randomly picked samples from each set on both occasions. The harvest index (hi) was defined as : hi = total flower biomass (g) X 100 total plant biomass (g) Qualitative studies in the kitchen gardens At five households located across three villages near Pondicherry, - 4 m2 plots were marked in the respective kitchen gardens. n three of the plots 2 kg vermicompost and in two of the plots an equal quantity of compost were applied. Five species of vegetables, one in each plot, with - 20 plants m2 were planted : lady's finger (Hibiscus esculentus), brinjal (Solanum melongena), cluster bean (Cyamopsis tetragonoloba), chilli (Capsicum annum), and tomato (Lycopersicon

7 esculentum). All the plots were irrigated whenever the rest of the kitchen garden was irrigated -which was normally once a day Tests of significance The significance of enhancement (E) or suppression (S) in the performance of the crossandra plants grown in compost vermicompost treated pots compared to the controls was assured by Student's t test. For each of the nine parameters used to assess the performance, statistical significance or othenrvise of the difference was assessed in terms of the confidence level (%) associated with the change. The tests were performed with software SMART (Arya and Abbasi,2001) based on the standard procedure of the Student's t test (Levin,l990). 3. Results and discussion The findings from the experiments with crossandra are summarized in Table 1. The pots containing soil amended with water hyacinth compost had crossandra plants achieving significantly better height, larger number of leaves, more favorable shoot : root ratio, greater biomass per unit time and larger length of inflorescence. n terms of root length, quicker onset of flowering and harvest index, too, the treated plants on an average performed better than the controls but the enhancement was not statistically significant. The positive impact was more pronounced in plants treated with vermicompost; indeed in respect of all the nine parameters there was statistically significant (at, 95% confidence level) enhancement in performance. Of particular interest is the enhancement in the flower yield and harvest index by vermicompost as these attributes directly enhance the benefits from the cultivation of crossandra. Observations on the five kitchen gardens also revealed total absence of any harmful effect of compost vermicompost. Rather, the farmer's view was that the vegetables grew better than normal on the treated plots. We may mention that as the success of these experiments became common knowledge in the villages where we are working, there has been a spurt in the utilization of water hyacinth through composting and vermicomposting.

8 Table 1 Effect of the application of water hyacinth compost vermicompost on the growth of Crossandra ( Cmssandm undulaefolia ) Attribute n control n pots treated with compost Enhancement (E) or Enhancement(E)or n pots treated suppression (S) in suppression(s)in with compost treated pots vermicompost treated vermicompost compared to controls. pots compared to controls. at confidence level at confidence level Number of leaves 90" day " day Total dry weight gorn day 180" day 17.76i iO i i f *1.42 E 90% E 98% E 95% E 98%

9 Table 1 continued. Days to first flowering 45i5.10 i Number of flowers per plant 90~ day 11.4i om day 19.4i3.01 inflorescence

10 Acknowledgement Authors thank Department of Science and Technology, Government of ndia, New Delhi, for sponsoring the study. References Arya,D.S., and Abbasi, S.A., SMART: A new software package for environmental trend analysis. Journal of the nstitution of Public Health Engineers, New Delhi, 2001, Gajalakshmi, S., Rarnasamy, E.V., Abbasi, S.A., 2001 a. Potential of two epigeic and two anecic earthworm species in vermicompoting water hyacinth. Bioresource Technology 76, Gajalakshmi, S., Ramasamy, E.V., Abbasi, S.A., 2001 b. Verrnicomposting of different forms of water hyacinth by the earthworm Eudrilus eugeniae, Kinberg. Bioresource Technology, in press. Gajalakshmi, S., Ramasamy, E.V., Abbasi, S.A., 2001c. Assessment of sustainable vermiconversion of water hyacinth at different reactor efficiencies employing Eudrilus eugeniae Kinberg, Bioresource Technology, 80, Gajalakshmi, S., Ramasamy, E.V., Abbasi, S.A., 2002 High-rate composting- vermicomposting of water hyacinth (Eichhomia crassipes, Mart. Solms). Bioresource Technology, in press. Levin, R.., Statistics for management. Fourth Edition. Prentice-Hall of ndia, New Delhi. Pandey, B.P., Taxonomy of angiosperms. Fourth edition. S. Chand and Company, New Delhi. Rajalingam, M., Development of know-how and its extension for the composting 1 vermicomposting of water hyacinth and other solid wastes. M.Phi1 thesis, Pondicherry University, Pondicherry.

11 Chapter 17 Effect of the application of neem verrnicornpost on the growth and yield of the vegetable plant, $olanum melongena Linn* S. Gajalakshmi and S.A. Abbasi Centre for Pollution Control & Energy Technology Pondicherry University, Kalapet, Pondicherry , NDA Abstract The impact of the application of vermicompost obtained from neem (Azadimchta indica) on plants was assessed in terms of growth and yield of the brinjal plant Solanum melongena Linn. Morphological, and yield attributes were studied in brinjal saplings treated with neem vermicornpost as compared to the untreated saplings. The studies reveal that application of vermicompost led to statistically significant improvement in the growth and yield of brinjal plants compared to the untreated plants. 1. ntroduction Earlier experiments were conducted to study the effect of composffvermicompost obtained from water hyacinth on the growth and yield of Crossandm unduleefolia, and on several vegetables (Gajalakshmi and Abbasi, 2002). The studies revealed that application of vermicompost led to statistically significant improvement in the growth and flowering of crossandra compared to the untreated plants. The impact of compost was also beneficial but a little less distinct than the positive impact of vermicompost. Qualitative studies were simultaneously conducted in kitchen garden owned by farmers. The farmer's view was that the vegetables grew better than normal on the treated plots. Hence in the present study, attempt was made to conduct quantitative studies on the effect of vermicompost on the growth and yield of plants. Pre-print of the paper due to be published in Environmental Technology 144

12 Brinjal is an erect, herbaceous, perennial plant. The leaves are simple, large and lobed. The flowers are blue in colour. The fruits are large, dark purple berries capped with thick persistent calyx (Varier, 1996). The fruits are used as vegetable. Sometimes the plant is grown for ornamental purpose (Usher, 1984). Since it is a common plant, fast growing and yielding, it is chosen for the study. 2. Methods All quantities mentioned below represent dry (oven dried at 105'C to constant) weights unless otherwise stated. 2.1 Neem vermicompost Neem has attracted global attention due to its potential as a source of natural drugs as also environment friendly pesticides (Agarwal, 1996). Studies were made to explore neem as a substrate for generating vermicompost. Freshly fallen leaves as well as partially dried neem leaves were collected and subjected to composting. Cornposting was done as per the procedure detailed elsewhere (Gajalakshmi et al, 2002). The neem compost was given as feed to the earthworms. The earthworms fed upon the neem compost more voraciously than they did on the mango leaf compost (Gajalakshmi et a/, 2002). The average CN ratio of neem vermicompost was 18.7( an average of 9 determinations). 2.2 Controlled experiments with S. melangina Two plots of 4 m2 area were marked out and 50 brinjal saplings of 10 days old were planted in each plot. One plot was supplemented with neem 1 kg/ m2 and the other plot was lefl untreated. Afler 2 months, the untreated control plot was also supplemented with neem vermicompost at the same rate as the test plot. The plots were uniformly irrigated once a day.

13 The plants were observed daily for the following parameters: plant height, root length, days to first flowering, number of flowers, number of fruits and fruit length. Another set of parameters - total plant biomass, fruit biomass, root- shoot ratio, fertility coefficient, harvest index - were studied on the 3oth, 60h, goth, 120th, and 150'~ day of the experiment by sacrificing 5 randomly picked samples from each set. The harvest index (hi) is defined as hi = total fruit biomass x 100 total plant biomass and the fertility coefficient is defined as number of fruits produced per plant x 100 total number of flowers per plant Tests of significance The significance of enhancement (E) or suppression (S) in the performance of the brinjal plants grown in vermicompost treated plots compared to the controls was assured by Student's t test. For all the parameters used to assess the performance, statistical significance or otherwise of the difference was assessed in terms of the confidence level (%) associated with the change. The tests were performed based on the standard procedure of the Student's t test (Levin, 1990). Results and discussion The findings from the experiments with brinjal are summarised in Table 1. The plot supplemented with neem vermicompost had plants achieving significantly better height, root length, greater biomass per unit time, quicker onset of flowering, and enhancement in fruit yield. n terms of fertility coefficient and harvest index too, in treated plots, there was statistically significant enhancement in performance. With the supplementation of neem vermicompost after 2 months in control plots, there was increase in plant height, root length, total biomass and number of flowers and fruits produced. The difference in the various parameters between treated plants and control

14 Table1 Effect of application of neem vermicompost on the growth and yield of brinjal (Solanurn melongena Linn) Attribute 1. Plant length, cm 30'~ day 60'~ day 90lhday 120thday 150'~ day 2. Root length, cm 30'~ day 60" day 90'~da~ 120h day 150'~ day 3. Shoot-root ratio 3oth day 60'~ day goth day 120'~ day 150'~ day n control plot 21.7 * * * * * i i t r i t i t t i 0.2 plot treated with venicompost 24.1 f f f f k i i i i i r i i t k 0.2 Enhancement (E) or Suppression (S) in vermicompost treated plot compared to control at confidence level E 90 % E >50% E 99% E z98 % E 50 % E 90 % E 80 % E 99 % E >50 % E 50 % i E >50% E 90 % E 98% E >SO% E (50 % 4.Total plant weight, g 3oth day 6oth day 90h day 120'~ day 150'~ day 22.2 i t i t i i t t r i 8.6 E 99 % E 99 % E >50% E >50% E 90 % 1 5. Days first flowering 38.6 i k 2.3 E 99 % i 6. Flowers per plant 3o"day 60' day 90' day 120'~ day 150hday 1.4i t i t t t t i k k2.1 E 99 % E >98% E >90% E ~ 5 0 % E 80% 147

15 .7. Fruit length, cm 1 -? 30lh day 6oth day 90lh day 12dh day 150'~ day 1.7 r i r i t r 0.3 8,7 t t Number of fruits produced 30h day 60h day goth day 120h day 150'~ day 0.2 t i t t t r % 4.8 t % 5.6 r t % 9. Total fruit! weight, g 1 3oth day i 6oth day goih day 120'~ day 150th day 10. Fertility coefficient 1 6oth day goth day 120'~ day 150hday t ,2 t t t k r t r 10.5 E >99 % 45.4 i E 99 % 37.4 t 10.1 >50 % 51.5 t E 50 % 59.3 t 9.4 / E 80 % 46.1f8.4 E 99 % 60.3f9.1 E >80 h 49.9t9.3 1 E >80% 58.8f8.6 i E (50% 59.8f4.3 E (50% 11. Harvest index 1 30" day i 60h day 90" day 120" day 150th day ,O 37.2r r r r f r f f 4.4 E 99 % E 98 % E (50 % E (50 % E (50 % i

16 plants treated with vermicompost after 2 months was not significant statistically. Hence it can be inferred that neem vermicompost has positive impact on plants. References Agarwal,A., What's in a neem? Down to Earth 14 {20), Gajalakshmi, S., and Abbasi, S.A., Effect of the application of water hyacinth compost/vermicompost on the growth and flowering of Crossandra undulaefolia, and on several vegetables. Bioresource Technology, in press. Gajalakshmi, S., Ramasamy, E.V., and Abbasi, S.A., Compostingvermicomposting of leaf litter ensuing from the trees of mango (Mangifera indica). Bioresource Technology, in press. Levin, R.T., Statistics for management. Fourth edition. S.Chand and Company, New Delhi. Usher, G., A Dictionary of plants used by man. CBS Publishers and Distributors, ndia. Varier, P.S.,1996. ndian medicinal plants. A compendium of 500 species Vaidyaratnam. AryaVaidya Sala Kottakal. Orient Longman.