Livestock Research for Rural Development 23 (10) 2011 | Guide for preparation of papers | LRRD Newsletter | Citation of this paper |
Biochar increased root development but did not affect yield of the above-ground biomass. The NM increased maize foliage growth three-fold and root development two-fold. Effluent increased maize foliage growth by 70% and root weight by 100%. There were cumulative effects of each of the interventions with the combination of biochar, NM and effluent supporting more than ten-fold increases in weights of maize foliage and roots compared with the control treatment of no intervention.
Key words: Amelioration, biotest, EM, gasification, local resources, rice bran sugar cane juice, yogurt
The use of a culture of beneficial micro-organisms to improve soil fertility was pioneered by a Japanese horticulturalist and agriculturist Dr Higa, Professor at the University of Ryukyus, in Japan. He named the culture “Effective Microorganisms – EM” describing it as a cocktail of beneficial bacteria that could be used for soil remediation. Higa’s findings were published in a book (Higa 1991a) and have served as the basis of a wide range of EM-based products that are sold commercially in many countries. Surprisingly, there appear to be few (if any!) published papers describing experiments in which EM have been used. Most references to EM are in presentations at scientific meetings (eg: Higa 1991b; Higa and Parr 1994). It is difficult to find information, neither on the exact composition of the various forms of EM that apparently are being used, nor on the ways to prepare them. A typical description of one commercial product is that it contains “five families of micro-organisms: lactic acid bacteria, yeasts, actinomyces, photosynthetic bacteria and fungi”.
Biochar: None (NB) or 2% of soil (B)
Effluent: With (E) or without (NE)
Native micro-organisms: With (M) or None (N)
Polyethylene bags (17 * 23 cm; capacity 1.5 liters) were filled with 1 kg of soil to which had been added 2% (by weight) of biochar (Photos 1 and 2). Maize seeds (n=3) were planted in each bag. After germination 1 or 2 plants were eliminated leaving only 1 maize plant as the experimental unit.
Photo 1. Biochar and soil before mixing. |
Photo 2. Biochar and soil after mixing. |
Soils
The fertile soil (SC) was taken from the upper 10 cm layer in the coffee plantation, which was shaded with Guamo (Inga edulis) trees (Photo 3). The sub-soil (SS) was from an area in which the top 1m of top-soil had been removed (Photo4).
Photo 3. Soil being taken from the coffee plantation shaded with Guamo trees. |
Photo 4. Sub-soil |
Natural microorganisms (NM)
Fertile soil (30 kg), taken in equal quantities from the top 10 cm layer in the
coffee plantation of the farm (Photo 4) and in the bamboo grove (Photo 5), was
mixed with 25 kg of rice bran and 2 kg of biochar A separate liquid
fraction was prepared from sugar.cane juice (12 litres) mixed with 1 litre of
goat milk yogurt and 10 litres of effluent from a biodigester charged with pig
manure. The solid and liquid fractions were then mixed together with an
additional 5 liters of biodigester effluent to ensure an appropriate texture of
the medium (not too wet nor too dry) and finally placed in a sealed 200 litre
PVC drum and left to ferment anaerobically.
Photo 5. Bamboo grove |
At the time of initiating the experiment (the mother culture was then 16 months old) the NM extract was prepared by suspending 3 kg of stock culture in 3 kg of water, mixing manually and then filtering through cloth to obtain a dark-colored liquid.
The NM was applied in quantities of 50 ml/bag at the time of planting the maize and again 10 days later. However, it was observed that the maize germination was irregular, especially in the NM treatments. All maize plants were then removed and new seeds planted 10 days after the second application of NM.
The effluent came from a continuous flow biodigester charged with manure from pigs fed a diet of sugar cane juice, rice bran, minerals and ensiled Taro leaves and stems (Rodriguz and Preston (2009). It contained 700 mg N per litre with 420 mg NH3-N/litre. The effluent was diluted with equal parts of water before application at intervals of 10 days in quantities to give the equivalent of 50 kg N/ha over the 50 days of the experiment..
The biochar was the residue after gasification of sugar cane bagasse in a downdraft gasifier (ANKUR Ltd, India). It contained 35% ash and 65% carbon with a pH of 9.0 (Rodriguez and Preston 2010). It was mixed with the selected soil at the level of 2% prior to filling the plastic bags.
The maize was harvested 50 days after planting. The height was measured from the base of the bag to the top of the highest leaf. The whole plant was removed from the bag, soil was removed from the roots, and roots and above ground biomass were weighed. The length of the longest root was also measured.
The data were analyzed using the general linear model option of the ANOVA program in the Minitab software (2000). Sources of variation were: treatments, biochar, effluent, NM, soil and the interactions biochar*effluent, biochar*NM, NM* effluent and error.
Results for individual treatments and main effects are shown in Tables 1 and 2 and Figures 1 and 2. Relevant interactions are in Figures 3 and 4. Figures 5 and 6 show the cumulative effects of biochar, native micro-organisms (NM) and biodigestor effluent on above-ground biomass and root growth of maize planted in fertile soils or in sub-soil.
Biochar increased root development but did not affect yield of the above-ground biomass (Table 1). The reason for the lack of effect on maize foliage yield may have been the low level used (2% of the soil) as in most contemporary experiments (Rodriguez et al 2009; Sisomphone et al 2011; Sokchea et al 2011) the minimum level used was 4% of the weight of the soil. The NM had a major effect on maize foliage growth (a three-fold increase) and on root development (a two-fold increase in root weight). Application of effluent increased maize foliage growth by 70% and root weight by 100%.
Table 1. Mean values for main effects of biochar, natural micro-organisms (NM) and biodigester effluent on height, on weight of above-ground biomass, on length and on weight of roots |
||||
Height, cm |
Above-ground biomass, g |
Root, cm |
Root, g |
|
Biochar |
|
|
|
|
With |
76.2 |
31.3 |
50.6 |
28.5 |
Without |
79.5 |
28.9 |
29.2 |
14.4 |
P |
0.75 |
0.73 |
0.003 |
0.02 |
Soil type |
|
|
|
|
SC |
78.3 |
33.3 |
41.0 |
23.3 |
SS |
77.4 |
26.9 |
38.8 |
19.6 |
P |
0.93 |
0.31 |
0.73 |
0.48 |
NM |
|
|
|
|
With |
95.1 |
45.4 |
45.8 |
29.4 |
Without |
60.6 |
14.8 |
34.0 |
13.5 |
P |
0.001 |
0.001 |
0.062 |
0.005 |
Effluent |
|
|
|
|
With |
87.7 |
37.7 |
44.5 |
27.5 |
Without |
68.0 |
22.5 |
35.3 |
15.4 |
P |
0.08 |
0.05 |
0.21 |
0.05 |
SEM |
7.10 |
4.73 |
4.70 |
3.88 |
There were cumulative effects of each of the interventions (Table 2 and Figures 5 and 6) with the combination of biochar, NM and effluent supporting more than ten-fold increases in weights of maize foliage and roots.
Table 2. Mean values for individual treatments for cumulative effects of biochar, native micro-organisms (NM) and biodigester effluent on height, on weight of above-ground biomass, and on length and weight of roots |
||||
|
Height, cm |
Above-ground |
Root, cm |
Root, g |
Fertile soil | ||||
No additives |
41.5 |
6.0 |
5.5 |
3.5 |
Bioc |
69.7 |
19.0 |
56.3 |
17.3 |
Bioc+NM |
90.0 |
32.0 |
39.0 |
38.0 |
Bioc+NM+Efl |
69.7 |
46.3 |
51.7 |
31.7 |
Efl |
71.0 |
14.0 |
39.0 |
17.0 |
NM |
87.0 |
37.5 |
29.5 |
10.5 |
Efl+NM |
106 |
57.3 |
43.8 |
29.0 |
Sub-soil | ||||
No additives |
39.0 |
2.3 |
12.8 |
2.5 |
Bioc |
39.3 |
7.0 |
34.0 |
8.3 |
Bioc+NM |
89.3 |
26.3 |
56.3 |
25.3 |
Bioc+NM+Efl |
93.5 |
55.0 |
52.5 |
45.5 |
Efl |
77.7 |
15.0 |
26.0 |
9.7 |
NM |
96.7 |
40.3 |
38.7 |
19.0 |
Efl+NM |
112 |
53.0 |
37.0 |
21.0 |
SEM |
19.8 |
13.7 |
12.1 |
11.5 |
Prob |
0.2 |
0.07 |
0.13 |
0.3 |
Figure 1. Effects of NM and biochar on above-ground biomass of maize |
Figure 2. Effects of NM on above-ground biomass of maize grown in fertile soil and sub-soil |
Figure 3. Effects of NM and biochar on root weight of maize |
Figure 4. Effects of NM on root weight of maize grown in fertile soil and sub-soil |
Figure 5. Effects of biochar alone, or with NM, or with NM and effluent, on above-ground growth of maize |
Figure 6. Effects of biochar alone, or with NM, or with NM and effluent, on root growth of maize |
At this stage of the research, carried out under practical farm conditions, it was not possible to identify the possible reasons for the dramatic effect of the NM on maize yield, as on the farm there were neither facilities for identification of the micro-organisms nor for analyses of the chemical composition of the final product.
The main objective was to develop a simple method for preparing the culture of NM using resources available on the farm., so that the technology could be made available to other small scale farmers practicing the integrated use of local resources for production of food and energy (effluent is a byproduct of food consumption by the pigs and the family; biochar is a byproduct of renewable energy production from sugar cane bagasse and forage trees; and the NM uses products/byproducts of several of the farm activities).
Future research will attempt to quantify the effect of the different components used in this first attempt at the production of a ”home-grown” culture of native micro-organisms.
The authors are pleased to acknowledge the .help received in: (i) establishing the experiment which was done during a training course at the farm for “young researchers” from CIPAV; and (ii) harvesting the maize and recording the results which was done as part of the training course for small-holder farmers from the Choco region of Colombia.
Boonchan Chantaprasarn and Preston T R 2004 Measuring fertility of soils by the bio-test method. Livestock Research for Rural Development. Vol. 16, Art. No. 78. http://www.lrrd.org/lrrd16/10/chan16078.htm
Higa T and Parr J 1994 Beneficial and Effective Microorganisms for a Sustainable Agriculture and Environment.. Atami, Japan: International Nature Farming Research Center. pp. 7. http://emproducts.co.uk/downloads/EM.pdf.
Minitab 2000 Minitab Reference Manual, Release 13.31 for Windows. Minitab Inc., USA.
Rodríguez L, Salazar P and Preston T R 2009 Effect of biochar and biodigester effluent on growth of maize in acid soils. Livestock Research for Rural Development. Volume 21, Article #110. http://www.lrrd.org/lrrd21/7/rodr21110.htm
Rodríguez L and Preston T R 2010 Gasification of fibrous crop residues and live stock production; essential elements in establishing carbon-negative farming systems. Livestock Research for Rural Development. Volume 22, Article #10. http://www.lrrd.org/lrrd22/1/rodr22010.htm
Rodríguez Lylian 2009 Integrated Farming Systems for Food and Energy in a Warming, Resource-depleting World. PhD Thesis Humboldt-University, Berlin. http://edoc.hu-berlin.de/dissertationen/rodriguez-lylian-2010-10-12/PDF/rodriguez.pdf
Sokchea H and Preston T R 2011 Growth of maize in acid soil amended with biochar, derived from gasifier reactor and gasifier stove, with or without organic fertilizer (biodigester effluent). Livestock Research for Rural Development. Volume 23, Article #69. http://www.lrrd.org/lrrd23/4/sokc23069.htm
Southavong S and Preston T R 2011 Growth of rice in acid soils amended with biochar from gasifier or TLUD stove, derived from rice husks, with or without biodigester effluent. Livestock Research for Rural Development. Volume 23, Article #32. http://www.lrrd.org/lrrd23/2/siso23032.htm
Received 9 September 2011; Accepted 20 September 2011; Published 10 October 2011