biocontrol of damping-off disease (sclerotium rolfsii sacc.) using ...

INTERNATIONAL JOURNAL Of ACADEMIC RESEARCH Vol. 3. No. 6. November, 2011, I Part
2.1. Propagation Actinomycetes and VAM
Actinomycetes obtained from collection Prof. Dr. Ir. Ika Rochdjatun Sastrahidayat (Mycology Laboratory
Faculty of Agriculture, Malang UB) first duplicated and regenerated by planting on PDA medium (Potato Dextrose
Jelly) new. Then they were incubated for five days. Furthermore, Actinomycetes culture is transferred in a medium
oatmeal-sand (OS). Oatmel-sand is a mixture of oatmeal with soil medium sand (1:1), and each distilled with 35 g
water and then add as many as 20 ml. Then insert all of it in glass bottles, covered with aluminum foil and then
sterilized in an autoclave for ± 3 hours. Actinomycetes pure cultures of PDA and taken by as many as five pieces of
cork borer (Ø 5 cm disk) that is then inserted into the OS which is a cold media. Actinomycetes inoculum was
incubated at room temperature for approximately two weeks. After two weeks, the inoculum Actinomycetes can
already be used.
VAM Propagation is done by using the media of maize were planted in plastic pots. Mycorrhizal spores will
breed as many as 1-2 spores that inoculate (2 cm below where the seed has been planted). Inoculated spores
placed in a paper cone made from tissue paper to avoid the leaking spores into the deeper part. Furthermore, corn
seeds covered with soil as high as 3 cm and the treatment done. After 45 dap (days after planting), the media has
been can be plant for corn and can be use for the manufacture of tablets VAM. Each tablet weighs 2 grams
mycorrhizal with mycorrhizal spore content of 50-10.
2.2. Actinomycetes and VAM inoculation on Soybean Seed
For soybean seeds that will get actinomycetes treatment, planted first before inoculated with actinomycetes
by soaking the seeds in a suspension of actinomycetes for four hours. Seeds that have been soaked then readied
to be planted in the field. VAM inoculation was conducted by simultaneously plant with soybean seeds of each
planting hole, planted with two seeds of soybean and two tablets of VAM.
2.3. Variable Observations
The variable be observed are include the rate of damping-off and infection rate (r) damping-off pathogens.
The attack level calculated by counting the number of plants that divided by the population of sick plants in each
treatment, and this observation is conducted every six days.
Growth of the plants that is included of plant height at the sample by measuring from the base of the stem to
the canopy height in clumps every six days. The plant samples used were 13 plants per plot. The variable is the
number of pods (pod fill and empty pods), pod weight, seed weight and weight of 100 seeds from each treatment.
Observations of plant crops such as seed weight after going through the drying process is done by drying the
beans on the drying tub for 3-7 days, this depends on the quality and quantity of sunlight.
Variety of microbes in rhizosfer calculated at each soil sampling. According to Waluyo [7] Microbial
population of each soil sample (grams) can be calculated using the following formula:
P = 푀 x 1
10⁻⁴
Description:
P = Population diversity of microbes per gram of soil
M = Number of colonies per petri dish
3. RESULTS AND DISCUSSION
3.1. Percentage of the death due to the Attack Plant Pathogen Sclerotium rolfsii
The results indicates the percentage of the deaths due to S. rolfsii soybean, and on Ratai varieties were not
significantly different at the plant ages 9, 15 and 21 dap, whereas plants at the age of 27, 33, 39 and 45 dap
showed significantly different results between the treatment of RAM (Ratai Actinomycetes + VAM) with RK (Ratai
Control). While are did not differ significantly Wilis variety of plants at the age of 9, 21, 27, 33, 39 (dap), whereas at
the age of 15 dap showed significantly different results. The mean percentage of plant mortality due to S. rolfsii on
soybean plants variety Ratai and Willis presented in Table 1.
Table 1. Percentage of death plant due to S. rolfsii on Ratai and Willis soybean plants varieties
Variety Treatment
9
Percentage of plant deaths (%) in the Age of Plants (dap)
15 21 27 33 39 45
Ratai
Actinomycetes + VAM
Control
0,00 a
0,00 a
0,76 a
1,36 a
4,85 a
6,82 a
6,67 a
9,24 b
6,67 a
9,47 b
6,67 a
9,85 b
6,67 a
9,85 b
Wilis
Actinomycetes + VAM
Control
0,15 a
0,15 a
0,30 a
1,67 b
4,92 a
7,42 a
6,44 a
9,32 a
6,89 a
10,30 a
6,89 a
10,38 a
6,89 a
10,38 a
Description: figures that accompanied the same letter in same column are not significantly different at test level of 95% t
From Table 1 can be seen that at first observation (7 dap) no difference in the percentage of plant death
caused by the attack of S. rolfsii among variety treated and non treated, each have a percentage of plant mortality
was 0%. Pathogen attack began to appear at 15 days after palanting, the number of dead plants on the not
controlled plot more than the controlled one. As the plants age, the percentage of deaths in the control plants
continued to grow and stop at 45 days after planting while the addition of death plant percentage on treatment
plants stopped after planting Ratai AM 27 dap.
B a k u , A z e r b a i j a n | 115