Article Type: Research Article Article Citation: Herry Z. Kotta, W.I. I. Mella, Suwari, and Paulus Bhuja. (2020).
PROVISION OF CHERT AS A SOURCE OF SILICONE (SI) FOR THE GROWTH AND YIELD OF
RICE (ORYAMMONIUM SULFATE SATIVA L.) TO SUPPORT A SUSTAINABLE CULTIVATION
SYSTEM. International Journal of Research -GRANTHAALAYAH, 8(12), 110-120. https://doi.org/10.29121/granthaalayah.v8.i12.2020.2637 Received Date: 03 November 2020
Accepted Date: 22 December 2020
Keywords: Chert Silicon Rice Nitrogen
Fertilizer Alkaline Soil Non-Alkaline Soil
A combination of silicon and macro nutrients has been proven to increase rice yield above the average of macro nutrient alone. Chert can contain up to 98% of silicon. Rice field in Timor can be alkaline or non-alkaline in nature. The solubility of SiO2 tends to be higher under acidic soil condition. The use of nitrogen fertilizer can reduce the acidity and hence may increase silicon availability. This research in designed to study the effect of the use of chert powder in combination with urea and ammonium sulfate on rice growth and yield. The study was a pot experiment laid-out based on complete randomized design with nine treatments and three replications. The treatments were control, chert powder 55 kg/ha, chert powder110 kg/ha, urea 100 kg/ha; ammonium sulfate 200 kg/ha, urea 100 kg/ha + chert powder 55 kg/ha, urea 100 kg/ha + chert powder 110 kg/ha, ammonium sulfate 200 kg/ha + chert powder 55 kg/ha, and ammonium sulfate 200 kg/ha + chert powder110 kg/ha. Results showed no significant difference in rice plant height and tillers among the treatments. Beside treatment effect, there was an indication of effect of factors other than treatment effects especially on the non-alkaline pots. It was suspected that the additional effect might be due to the presence of allelophatic substances. Therefore, it is suggested to have a future study on a combined effect of allelophatic substance and treatments assigned to this study to observe such an effect on rice growth and yield.
1. INTRODUCTION1.1. BACKGROUNDAccording to Makarim (2003), the Si content in paddy fields in general tends to be
negative, because the paddy soil continuously releases Si to maintain rice
plant growth but Si input is very little or even non-existent. According to Makarim (2003), every year every hectare of wetland will
lose 995 kg of SiO2, because it is absorbed by rice plants, while
the input for SiO2 comes from fertilizers of 100 kg/ha, from compost
140 kg/ha, and from irrigation 291 kg/ha. Lack of silica nutrients will result
in unproductive land and rice plants not growing optimally. Rice plants lack silica, their leaves droop,
their root absorption of nutrients is not good, rice plants are susceptible to
disease and pests, translocation of photosynthesis results is less efficient,
root oxidizing power decreases, thereby reducing rice plant resistance to Fe,
Al and Mn poisoning (Makarim et al., 2007; Ma and Yamaji, 2008). With sufficient silica, it will reduce the
use of phosphate and urea fertilizers by more than 50% of the standard dose;
neutralizing soil pH which generally tends to be acidic due to urea and
pesticides; reduce the rate of transpiration (evaporation) so that it is
efficient in using water and is more resistant to drought. Makarim (2003) states that for optimal rice fields (irrigated rice fields)
silica nutrition is formulated to contain 20-22% SiO2; P2O5
10-12%; and the dose of administration is 200 kg / ha. For other rice fields
such as rainfed lowland, dry land and tidal swampland, the silica nutrient
formulation contains 24-26% SiO2; P2O5 10-12%;
with a dose of 200 kg / ha. The benefits of the element silicon (Si) in
plant growth have not been given much attention, either by experts, governments
or farmers. Without Silica, plants can still grow. But actually, the function
of nutrients that are usually available in the form of SiO2 (silica)
is important for Gramineae plants, especially rice and sugarcane (Tisdale, et
al., 1985; Mengel and Kirby, 1987; Makarim et al., 2007). Silica plays a role in the formation of plant
cell walls, strengthening plant growth so that it grows upright and can capture
sunlight for optimal photosynthesis. In addition, Silica also strengthens the
resistance of stems and leaves against pests and diseases and acts as a
counterweight to other nutrients, such as phosphates and trace elements which
are toxic. Silicon
for rice plants generally comes from various sources such as irrigation water,
soil, fertilizers (organic and inorganic) (Ma and Takhashi, 2002; Rao and Susmitha,
2017). In addition, many experiments by experts use silicate rock (Pereira, et
al. al. 2004; Rao and Susmitha, 2017) and even silica
gel is also used to provide Si for rice plants (Ma and Takahashi, 2002). Ma and Takahashi (2002) calculated that in Japan, rice plants
receive a supply of SiO2 per ha of 300 kg (the amount of irrigation
water for rice is 14000 tons per ha and the SiO2 content in
irrigation water is 21.6 ppm). Soil in Timor, which is formed from weathering of limestone (marl
and raised coral), has a high SiO2 content, as stated by Mella and Mermut (2010) that the
SiO2 content in Alfisol soil and Mollisol soil formed on the raised reefs of Timor Island is
as big 42.6 ± 3.3% (w / w) and 45.8 ± 3.5% (w / w), respectively. Sources of Si from rocks/minerals containing SiO2 that
have been tested for rice are silicate clay and schists (Pereira, et al. 2004)
and silica powder (Rao and Susmitha, 2017), and
silica gel (Ma and Takahasi, 2002). Rao and Susmitha (2017) use silica powder (99% purity) at a dose of
100 kg per ha to fertilize rice and they find that silica powder can be used as
an ingredient in providing Si for rice plants. Ma and Takhashi
(2002) suggest that silica gel containing very high SiO2 can
dissolve in the soil to provide Si for rice plants. However, Pereira, et al.
(2004) also stated that schist and silicate clay did not contribute to
providing Si for rice plants. According to Ma and Takahasi (2002), the
amount of available Si in the soil depends on the parent material that forms
the soil. Soil derived from volcanic ash containing 28.2 mg available Si per
100 g of soil; while soil derived from Si granite rocks is available in the
soil as much as 5.5 mg per 100 g of soil. Silicon for plants can also come from compost. The Si content in
organic fertilizers depends on the type of compost material. Compost which
consists of materials containing high Si such as grass-hay will contain more Si
than compost made from legume crop residues (Mengel
and Kirby, 1987; Tisdale et al., 1985). This is because rice absorbs more Si
than legumes (soybean) (Mengel and Kirby, 1987). In
an experiment cited by these two experts, it was suggested that giving Si at
the same dose of 162 mg Si per L caused rice plants to absorb 124 g of Si while
soybean absorbed only 4 g. According to Ma and Takhashi
(2002), rice straw contains up to 20% Si. Chert is a fine-grained, hard, compact silicaan
rock formed by silt-sized quartz crystals (micro-quartz) and chalcedony, a form
of silica made of radiating fibers several tens to hundreds of micrometers in
length. It is usually dark gray,
blue, black, or dark brown and is mainly found in the form of nodules in
sedimentary rocks such as limestone or limestone. Since the Stone
Age, chert has been used to make weapons and tools such as swords, arrowheads,
knives, axes, etc. This mineral is a sedimentary rock deposited
in the deep sea (abyssal), which is based on the micro-fossil content of
Radiolaria (Wakita, et al 1996) showing that this
unit is of upper limestone age, while red limestone is sedimentation of
limestone plankton that may accumulate in local elevated parts. local. Generally, chert beds are composed of
residues of silica-producing organisms such as diatoms and radiolaria. These
deposits result from sedimentation, compaction and recrystallization
(lithification) of organic silica sludge that accumulates on the deep ocean
floor. This organic silica mud accumulates together under plangtonic zones of radiolaria
and diatoms while living on the surface of water with warm temperatures. When
these organisms die, the shells of these organisms are slowly deposited on the deep-sea
floor where they accumulate which are still separated from each other. These
materials are deposited far from the land arc to the ocean floor, when the
terrigenous sediment supply is low, and in the deepest part of the abyssal
plain there is a limit called the carbonate compensation depth (CCD),
where the accumulation of calcareous materials cannot form. This is
because one of the properties of water is cold water will bind more CO2 than
warm water. On the seabed, there is a clear boundary where the lower CO2 content is
higher. Below this limit, the CO2 content is very
high as a result, the carbonate-containing organisms will dissolve in the CCD
so that they will not settle because they never reach the ocean
floor. This carbonate compensation depth is located about
2,500 meters or 2.5 kilometers below sea level. Above the carbonate
compensation depth, about 2,000 meters, there is an area called
the lysocline. Here, some of the
carbonate has started to partially dissolve. Some chert layers do not
necessarily come from organic matter. It could be from silica
precipitation that comes from the same magma chamber in the underwater basaltic
(pillow lava) which experiences precipitation along with chert layers. Based on the results of research conducted by
the Mining and Energy Office of South-Central Timor Regency in 2003, in the
area of South Mollo District, it was
stated that chert extracted materials were exposed in the Fatumnasi,
Tune, Tunua, Ajaobaki, Netpala, Bosen, Eonbesi, Bonleu, Besana, Fatukoko, Binaus, Biloto and Oinlasi with total
volume: 1,907,812,500.00 (m3), with SiO2 levels ranging
from 63 - 98%. Until the research proposal was submitted, the chert mining
material was only used for pavement. Factors
influencing the availability of Si in soil dissolution are pH and mineral type
(Mengel and
Kirby, 1987; Tisdale et al., 1985). Available silicon (available form Si (OH)4,
silicic acid) is present in the soil at a very wide pH range between 2 and 9.
However, Si availability is also influenced by the content of Al and Fe oxides
in the soil. Soils with Al oxide content have higher available Si than soil
containing Fe oxide. Therefore, acid soils tend to have more available Si than
alkaline soils and applying lime will reduce the absorption of Si by plants (Mengel and Kirby, 1987). Nitrogen oxidation has long been recognized as a process that
causes the release of H+ ions and therefore lowers pH (Brady and
Weil, 2002). When nitrogen fertilizers such as urea or ammonium sulfate break
down in the soil, it will produce NH4+ ions (available
form for plants) which, if the soil conditions are well aerated, these ions
will immediately undergo oxidation and produce nitrate ions (NO3-,
which is also the available form). This process will produce H + ions which contribute
to increasing soil acidity (decreasing soil pH). The use of urea and ammonium sulfate
fertilizers does increase rice yields; however, the N element can cause rice
plants to be susceptible to abiotic stresses such as lying down and drought as
well as biotic stresses such as attack by pest organisms and disease causes.
Thus, giving chert powder as a source of Si and nitrogen fertilizers (urea and
ammonium sulfate) is expected to provide information on mutually beneficial
effects on rice growth and yield. Decreasing soil pH through dissolving urea and
ammonium sulfate fertilizers affects soil pH to different degrees. The decrease
in soil pH will be greater by dissolving ammonium sulfate than urea because the
acidity index of urea is lower than the acidity index of ammonium sulfate (Fageria et al., 2010; Singh, 2010). The equivalent acidity
of urea and ammonium sulfate are 80-84 and 110, respectively. Although Si is the second most abundant element in the earth's crust and of course in the soil and almost all types of soil minerals, its availability is highly dependent on the root environment, for example soil pH and soil mineral types such as the presence of iron oxide and aluminum oxide minerals (Tisdale, et al. 1985; Mengel and Kirkby, 1987). Silicon will be available in higher concentrations in an acidic environment than an alkaline environment. Lime application will reduce the Si concentration in the soil solution (Mengel and Kirby, 1987). On the other hand, giving compounds or elements that acidify the soil will increase the solubility and at the same time the availability of Si in the soil. Urea and ammonium sulfate fertilizers are inorganic fertilizers that have moderate and high soil acidification levels, respectively (http://agropedia.iitk.ac.in/content/acidity-and-basicity-fertilizers; downloaded 27 March 2020 https://www.blinc.com/role-nitrogen-fertilizer-soil-ph; downloaded March 25, 2020). It has long been known that nitrogen oxidation from nitrogen fertilizers such as urea or ammonium sulfate is one of the processes that causes an increase in the concentration of H+ ions in the soil solution (causing a decrease in pH) (Brady and Weil, 2002). However, giving nitrogen fertilizers such as urea or ammonium sulfate in balance with fertilizers containing other nutrients such as Si will improve soil health and quality (Singh, 2018). 1.2. HYPOTHESISThis research is
based on the hypothesis that: 1)
Plant growth is
better in the treatment of fertilizer and chert powder than the treatment
without fertilizer. 2)
Plant growth will
be better in the combination treatment of urea fertilizer, ammonium sulfate
fertilizer with chert powder than contro and
fertilizer and chert individually. 1.3. OBJECTIVES1) Knowing the effect/response to growth and yield of rice plants that are given and not given chert as a source of silica and without urea fertilizer, as an effort to support a sustainable rice cultivation system. 2) Determined the effect of giving chert as a source of silica combined with urea fertilizer for growth and yield of rice plants. 2. RESEARCH METHODSThis study was a pot experiment arranged in a complete randomized design with nine treatments and three replications. Two kinds of soils were utilized namely alkaline and non-alkaline rice soils. The treatments were control, chert powder 55 kg/ha, chert powder110 kg/ha, urea 100 kg/ha; ammonium sulfate 200 kg/ha, urea 100 kg/ha + chert powder 55 kg/ha, urea 100 kg/ha + chert powder 110 kg/ha, ammonium sulfate 200 kg/ha +chert powder 55 kg/ha, and ammonium sulfate 200 kg/ha + chert powder110 kg/ha. Rice variety used was Situ Bagendit, a variety that can be grown in a dry-land or in an inundated soil. Plant growth components were studied were plant height, number of tillers, lodging, number of panicles per plant, nmber of grain per panicle, total seed weight per pot. Chert rock was extracted from Tobu in South Central Timor and Nunpene of North Central Timor. The chert rock was ground to pass a 500-mesh filter. Nitrogen fertilizer applied were urea and ammonium sulfate. The chert is crushed to pass through a 500-mesh sieve and given to the soil before planting. The nitrogen fertilizers were split into three equal dosage and applied consecutively at planting, vegetative fast growth stage, and at early generative stage. The chemical properties of the soils are presented in the following. Table 1: Chemical properties of soils utilized in this study.
Analysis of variance was performed at a 5% level of significance. 3. RESULTS AND DISCUSSIONSPlant growth in the form of plant height and number of tillers measured every two weeks after planting are presented for alkaline and non-alkaline soils. 3.1. ALAKALINE
SOIL
Plant height Observation of
plant growth every two weeks showed an increase in plant height for all
treatments (Figures 4.1 and 4.2). The figure below shows that the average plant
height at two weeks after planting was 20-25 cm. Whereas, in the last
observation all plants from all treatments showed a height of about 50-60 cm.
From the first observation to the last observation, plant height did not appear
to differ between treatments. When compared with the description of this rice
variety (Var Situ Bagendit), the plant height at two
months after planting is below the height of the description (description
height 99-105 cm, http://bpatp.litbang.pertanian.go.id/ind/). Plant height
according to the variety description is usually the height of the plant that is
treated with technology and a good growing environment. This research is a
potted study that uses a plastic bucket planting container which greatly limits
the growth of plant roots because the amount of soil that can be trampled by
the roots is limited by the bucket wall. The foregoing may
be the reason for the absence of differences in plant height. The variance checks
on plant height (Table 4.1) shows that the treatment did not show a significant
effect on plant height in the last observation. Thus, the plants either fertilized
or not fertilized, plants that were given chert or not given chert powder, all
had plant heights that were not significantly different at α = 0.05 with a
coefficient of variability (CV) of only 8%.
Figure
1: Plant height at each
observation (once every two weeks) Note: K =
control; R1 chert powder 55 kg/ha; R2 of chert powder 110 kg/ha;U = Urea 100 kg/ha;Z = ammonium sulfate 200 kg/ha.UR1 = Urea 100 kg/ha +
chert powder 55 kg/ha;UR2 = Urea 100 kg/ha + chert powder 110 kg/ha;ZR1 =
ammonium sulfate 200 kg/ha + chert powder 55 kg/ha;ZR2 = ammonium sulfate 200
kg/ha + chert powder 110 kg/ha.
Figure 2: Plant height at last observation Note: K =
control; R1 chert powder 55 kg/ha; R2 of chert powder 110 kg/ha; U = Urea
100 kg/ha; Z = ammonium sulfate 200 kg/ha. UR1 = Urea 100 kg/ha + chert powder
55 kg/ha; UR2 = Urea 100 kg/ha + chert powder 110 kg/ha; ZR1 = ammonium sulfate
200 kg/ha + chert powder 55 kg/ha; ZR2 = ammonium sulfate 200 kg/ha + chert
powder 110 kg/ha. Table
1: Check the height variance of the last crop
Number
of tillers Like plant height, the number of tillers on alkaline soils also shows an increase over time. However, the number of tillers increased very slightly at each observation. When transferring seedlings, plants from all the treatments planted were only one tiller. In the second observation, almost all of the treatments had grown tillers except for treatment R2 and UR2(Figure 4.3).
Figure 3: Number of tillers per pengamtan. Note: K =
control; R1 chert powder 55 kg/ha; R2 of chert powder 110 kg/ha; U = Urea
100 kg/ha; Z = ammonium sulfate 200 kg/ha. UR1 = Urea 100 kg/ha + chert powder
55 kg/ha; UR2 = Urea 100 kg/ha + chert powder 110 kg/ha; ZR1 = ammonium sulfate
200 kg/ha + chert powder 55 kg/ha; ZR2 = ammonium sulfate 200 kg/ha + chert
powder 110 kg/ha. Planting before flowering, plants from all treatments already had different numbers of tillers. The question is the control treatment and UR1 has a higher number of tillers compared to the number of tillers in other treatments (Figure 4.4). The number of tillers in these two treatments was 14 while in the other treatments, the number of tillers ranged from 6 to 10. However, statistically, the difference in the number of tillers was not significant at α = 5%. It also has a small coefficient of variability (CV) of 4.52% (Table 4.2). Figure 4: The number of tillers at the last observation Table2: Check for a variety of tillers at the last observation
3.2. NON-ALKALINE
SOIL
Plant
height Plant height at planting for all treatments was the same. However,
after two weeks after planting, the height of the plants appeared to be
visually different. This difference was not that big and all the plants
were between 18 cm to 20 cm in height. Observing the following weeks,
all plants experienced an increase in plant height until the last observation,
plant height ranged from 30 cm to 55 cm. As only in alkaline soils, plant
growth is also hampered by limited growth in plants. However, an
interesting thing that happens on non-alkaline soils is that the plants are much
shorter than the height of the plants on alkaline soils. This may
be caused by the effects of a l lelopati on
a non-alkaline soil. The non-alkaline soil used in this experiment comes
from paddy soil which has not been planted with rice for a long time so that
when the soil was taken for this experiment, the land was overgrown with thick
and dense grass. Note: In the last few years, the rice field area from
which the experimental land is based has not had enough water to cultivate the
entire rice field there. Allelopati is difined as chemical substances
produced by the roots, stems, leaves, flowers, fruits, seeds and even
a plant which can inhibit the growth or even toxic to other plants
(Putnam and Tang (1986). All types of plants have the ability to produce allelopati. Type grass -Grass (Poaceae)
has the ability to produce this chemical According to Sánchez-Moreiras (2003), Poaceae has
target vegetation types from various families and not the least the target is
also from P. oaceae species. Therefore,
most likely, inadequate growth. of the rice plants in this
experiment in non-alkaline soils due to the presence of allelopathy. The presence of allelopathy also affects various soil properties such as phenolic acids affecting pH, electrical conductivity, availability of potassium (K+), and dissolved chloride (Cl), as well as the nitrification process (Kruse et la., 2000).
Figure 5: Plant height at different observations made every two weeks after planting Note: K =
control; R1 chert powder 55 kg/ha; R2 of chert powder 110 kg/ha; U = Urea
100 kg/ha; Z = ammonium sulfate 200 kg/ha. UR1 = Urea 100 kg/ha + chert powder
55 kg/ha; UR2 = Urea 100 kg/ha + chert powder 110 kg/ha; ZR1 = ammonium sulfate
200 kg/ha + chert powder 55 kg/ha; ZR2 = ammonium sulfate 200 kg/ha + chert
powder 110 kg/ha. The last observation on plant height also ranges from about 30 for plant treated with urea 100 kg/ha+ chert powder 110 kg/haand the tallest (52 cm) was in treatmentR1 (chert powder 55 kg/ha). Although there is a tendency for differences in the height of rice plants from various treatments, however, statistically, all of these plant height differences are not in a significant degree of 5% difference with a low coefficient of diversity (CV = 13%) as shown in the variance fingerprint table below. (Table 3).
Figure 6: Plant height in the last observation. Note: K = control; R1 chert powder 55
kg/ha; R2 of chert powder 110 kg/ha; U = Urea 100 kg/ha; Z = ammonium
sulfate 200 kg/ha. UR1 = Urea 100 kg/ha + chert powder 55 kg/ha; UR2 = Urea 100
kg/ha + chert powder 110 kg/ha; ZR1 = ammonium sulfate 200 kg/ha + chert powder
55 kg/ha; ZR2 = ammonium sulfate 200 kg/ha + chert powder 110 kg/ha. Table
3: Check for variance in plant height at the last observation
Number
of tillers The number of tillers / seedlings of rice plants planted in non-alkaline soil is one seed per pot. Generally, this experimental plant begins to produce new tillers at weeks 2 to 4 after planting. However, the UR1 treatment (Urea 100 kg / ha + chert powder 55 kg / ha) the number of tillers remained one until the last observation. This may be caused by chemical resistance due to the presence of allelopathy of the field grass that grows on the soil used as a non-alkaline growing medium (as described in section 4.2.1 above. At the end of the planting, there is a difference in the number of tillers. rice in all treatments It was seen that the R2 and U treatments had more tillers than the other treatments It was also seen that there was a grouping of the number of tillers in the last observation, namely the R2 and U groups in one group and K, UR2, ZR1, ZR2, and Z.
Figure7: The number of tillers with
different treatments was observed every two weeks after planting Note: K =
control; R1 chert powder 55 kg/ha; R2 of chert powder 110 kg/ha; U = Urea
100 kg/ha; Z = ammonium sulfate 200 kg / ha. UR1 = Urea 100 kg/ha + chert
powder 55 kg/ha; UR2 = Urea 100 kg/ha + chert powder 110 kg/ha; ZR1 = ammonium
sulfate 200 kg/ha + chert powder 55 kg/ha; ZR2 = ammonium sulfate 200 kg/ha +
chert powder 110 kg/ha. Although there appeared to be differences in the number of tillers between treatments, especially in the last observation (Figure 4.8), the analysis of variance of number of tillers as shown in Table 4, all these differences were not statistically significant at the 5% difference. Even this absence of significant difference needs attention because it turns out that the coefficient of variance is quite high, namely 66%. This may again be due to the inhibition of plant growth on these non-alkaline soils, which stem from the possibility of chemical compounds that are allelopathic in nature produced by thick and dense field grass in the paddy soil where the experimental soil was taken.
Figure 8: The number of rice tillers in the
last observation from various fertilization treatments Note: K = control; R1 chert powder 55
kg/ha; R2 of chert powder 110 kg/ha; U = Urea 100 kg/ha; Z = ammonium
sulfate 200 kg/ha. UR1 = Urea 100 kg/ha + chert powder 55 kg/ha; UR2 = Urea 100
kg/ha + chert powder 110 kg/ha; ZR1 = ammonium sulfate 200 kg/ha + chert powder
55 kg/ha; ZR2 = ammonium sulfate 200 kg/ha + chert powder 110 kg/ha. Table
4: Investigate the various effects of treatment on
the number of tillers in the last observation
4. CONCLUSIONThe results and discussion led to the following conclusions: The application of fertilizer and chert powder in various doses did not affect the growth of rice plants grown on alkaline or non-alkaline soils. The growth of rice plants on alkaline soils was actually better than that of non-alkaline soils, which is probably due to the allelopathic effect of non-alkaline soils. 5. SUGGESTIONWith the difference in plant growth on alkaline and non-alkaline soils which are not caused by differences in treatment but possibly due to the presence of allelopathic compounds, it is suggested for allelopathic research on non-alkaline soils used in this experiment, especially to assess the impact of allelopathy and the combination with the treatment tested on soil properties and growth of rice plants. SOURCES OF FUNDINGThis research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. CONFLICT OF INTERESTThe author have declared that no competing interests exist. ACKNOWLEDGMENTNone. REFERENCES [1] Brady, N.C. and R.R. Weil. 2002.
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