Study in the Use of Organic Mulch and Varieties on Production Cabbage (Brassica oleraceae L.) at Different Altitude

This study aims to assess the effect of various types and varieties of organic mulch on the quantity and quality of cabbage plants (Brassica oleraceae L.) at various altitudes. This research using Random Design Group (RDG) arranged as factorial by 2 factors. The first factor is testing four varieties of cabbage: V1 (KK-Cross), V2 (Grand 11), V3 (Silvia), V4 (Talents). The second factor is testing a variety of organic mulch: M0 (without mulch), M1 (rice straw mulch), M2 (rice husk mulch). The results showed that the KK Cross varieties have crop weight (1226.11 g) or 49 tons haa -1 heavier than other varieties at an altitude of 110 meters above sea level. At an altitude of 400 meters above sea level Grand 11 Varieties resulted in crop weight (1125.00 g) or 45 ton ha -1 is heavier than other varieties. Furthermore, at an altitude of 1350 meters above sea level Grand 11 varieties produce crop weight (1055.56 g) or 42.2 tons ha -1 heavier than other varieties. 3). Rice straw mulch is better at producing crop volume (985.25 ml) than other organic mulch treatment at an altitude of 110 meters above sea level. At an altitude of 400 above sea level rice husk mulch is better (831.83 ml) in producing the crop volume and at an altitude of 1350 meters above sea level treatment without mulch is better (984.83 ml) in volume produces of crop compared to other treatments 4). Indicators of crispy on cabbage planted at an altitude of 110 meters above sea level is the Talent without mulch and mulch varieties of rice husks and varieties Grand 11 mulched straw and rice husks. At an altitude of 400 meters above sea level the crispy indicators are on the variety KK Cross with straw rice mulch. At an altitude of 1350 meters above sea level crispy indicators contained in all varieties that were given rice straw mulch and KK Cross varieties with rice husk mulch.


INTRODUCTION
Various studies of food consumption in general revealed that the consumption of vegetables and fruit per capita income has greater income elasticity than the food consumption of carbohydrates and the elasticity values are greater in households with higher income levels. That is, the economic development which has led to an increase in household income will lead to an increase in consumption per capita which is higher in vegetable varieties and fruit compared to carbohydrate foods.
The Increased per capita consumption is expected to be faster in urban areas than rural areas because the income elasticity of fruit and vegetable consumption tends to be higher in urban areas. This trend may occur because the income of the urban population is greater than the villagers and changing consumption patterns associated with social dynamics such an understanding of the nutrients in general are better in the city area.
That fact becomes initial data to be used as a benchmark in the development of cabbage commodity. This is corroborated by the results of the analysis of the World Bank in 1991, the demand for vegetables in Indonesia is projected to increase by 5 percent per year between 1998 and 2010. Cabbage plays an important role in the food industry of the country, because it can be processed into a variety of dishes from street food stalls to five star hotels.
The data of cabbage production in Central Sulawesi region in 2010 was 3.752 ton, in 2011 was 4,001 tons, in 2012 was 1,139 tons and in 2013 was decreased to 871 tons. Entering the year of 2014,the production rose to 8.510 tons (Central Bureau of Statistics and the Directorate General of Horticulture, 2014). The figure shows that the potential of this type of cabbage vegetable is still relatively high, it can be seen from the marketing distribution of cabbage from Palu can be marketed inter-islands such as to Kalimantan.
The figure shows that the potential of this type of cabbage is still relatively high, it can be seen from the high demand of this kind of vegetables from the sea food restaurants that spread in urban areas to the countryside. Besides, these kinds of vegetables are chosen by the inter-island traders as business commodities that possess high demand.

Design of Experiments and Technical Implementation
Research using Random Group of Factorial pattern with 2 treatment factors, the first treatment is testing four varieties of cabbage: V1 (KK-Cross), V2 (Grand 11), V3 (Silvia), V4 (Talents). The second factor is the straw mulch treatment with levels: M0 (without mulch), M1 (rice straw mulch), M2 (rice husk mulch). The overall combination is 12 treatments with the total number of plots is 36 sample plots at each research site.
Data obtained during the observations were subsequently analyzed by analysis of variance and if there is a difference between the treatments then continued by Honestly Significant Difference Test (HSD) 5%. Table 1 show that the interaction between rice straw mulch and KK Cross varieties at altitude of 110 m above sea level produced the highest number of leaves (4.78). At an altitude of 400m above sea level the grand 11 varieties which was given rice husk mulch have the highest number of leaves (5.44) compared to other treatments. While at an altitude of 1350m above sea level, the variety of Talenta without mulch produced the highest number of leaves (4.67) compared to other treatments. The condition indicated that cabbage grown in lowland require micro climate conditions around the plants not to be overheat. Because it is known that at that age, the plants are still in the vegetative phase characterized by the formation of vegetative organs.

Number of leaves
Solo Samosir and Ambo Ala (2002) suggests the young plants that grow well can develop roots more quickly to absorb nutrients available in the soil before the soil washed away or fixed. Sufficient supply of nutrients from the roots to the top of the plant can support the growth of the plant canopy. Plant canopy that grow faster can cover the ground earlier and directly influent in reducing water evaporation from the soil. Gunasekera G.P. research results, (2006) explains that the early growth of cabbage is supported by a lower temperature because it will accelerate the rate of formation of the canopy, the interception of radiation and increase transpiration produces high dry material. Soil moisture surface layer is better preserved can increase nutrient uptake by plant roots. The above mentioned conditions supported with rice straw mulching brindle arranged between the crop rows double rows system. Rice straw mulch in this way is relatively thicker and denser so that its influence in conserving ground water and suppress weeds is greater.

0,77
Note : The number that accompanied by letter is similar to the similar rows are not significantly different at HSD 5% Test.

Leaf Area Index
Leaf area index is a picture of the leaf surface area ratio of land occupied by crops growing. The growth rates of the plants are affected by the rate of net assimilation and leaf area index. The net assimilation rate is high and optimum leaf area index can improve plant growth. Increased leaf area in the absorption of CO2 for photosynthesis is supported by the structure of the leaves are ideal even in conditions of environmental stress is the ability of plants to adapt in order to remain sustainable (Gardner, et al., 1991). According to June (2003), Leaf is one of the most important organs of the plant. Leaves are the place for the photosynthesis process to draw up the plant dry materials. Table 2 shows that the widest leaf area index for KK Cross varieties which were given rice straw mulch at an altitude of 110 m above sea level has relation to the number of leaves. This is consistent with Gomies et al. (2012) result research that the leaf area index is closely related to the number of leaves. Leaf is the main organ that functions in photosynthesis because the leaves have pigments that play a role in absorbing the sunlight. The energy of the Sunlight needed for the process plant growth and development of plants. The sunlight received by the leaves in large quantities will provide more leaves formation compared to the leaves that received fewer sunlight.   Note : The number that accompanied by letter is similar to the similar rows are not significantly different at HSD 5% Test.

NAR and CGR
The highest Value of net assimilation rate (Table 3) is on an altitude of 110m above sea level on a variety of Talenta by using rice straw mulch and the lowest is at an altitude of 400m above sea level on a variety of Talenta by using rice husk mulch. It is suspected that the rice straw mulch at altitude of 110m above sea level have not been able to suppress a high temperature around the plant, causing the respiration rate is high compared to the Talenta variety of other treatments. By contrast, in an altitude of 400m above sea level Talenta which were given rice husk mulch would have a low net assimilation value rate, it means that the response varieties of Talenta by using rice husk mulch is low in utilizing the temperature around the plant. The growth rate of the plant is the plant's ability to produce dry ingredients result of assimilation per unit area per unit time (g cm -2 day -1 ). The growth rate of the plants running at maximum speed when the temperature is at the optimum conditions (suitable), if other factors are not to be limiting (Jumin, 2002).
The result of the research (Table 4) showed that the varieties of KK Cross which were given rice straw mulch and planted at an altitude of 110m above sea level, contributes a higher value on the growth rate of plants compared to other treatments. This indicates that rice husk mulch around the plant was able to maintain a good temperature for plant growth of KK Cross cabbage varieties grown at an altitude of 110m above sea level. The results of research of Nkansah et al (2003) explains that mulching with organic materials rice husk able to maintain soil temperature and humidity around the plant compared to controls in tomato plants. Soil temperature and humidity suitable for KK Cross cabbage as shown by some researchers that the KK-Cross planted in climates between 18.6 -26,9 0 C can have weight up to 2,52 kg crop -1 (Nathoo, et al., 1998). The results of this research is also supported by the high net assimilation rate in KK Cross with rice straw mulch and rice husks mulch are no different from the varieties of Talenta at an altitude of 110 m above sea level. 3,7x10 -5 b 5,3x10 -5 c 4,0x10 -5 bc 3,4x10 -5 ab 3,3x10 -5 ab 3,5x10 -5 ab 3,1x10 -5 ab 3,4x10 -5 ab 3,3x10 -5 ab 2,5x10 -5 a 3,2x10 -5 ab 2,9x10 -5 ab 1,0x10 -5 400 m Above sea level Without Mulch Rice straw mulch Rice husk mulch 2,3x10 -5 a 2,4x10 -5 a 2,4x10 -5 a 2,5x10 -5 a 3,1x10 -5 ab 3,6x10 -5 b 2,6x10 -5 a 2,8x10 -5 ab 2,8x10 -5 ab 2,5x10 -5 a 2,7x10 -5 a 2,8x10 -5 ab 8,0x10 -5

The Age at Harvest
The types of rice straw mulch and rice husk influence the age at harvest (Table 5) KK Cross and Grand 11 varieties are faster in every research location. This shows that both varieties are able to respond to the range of temperatures that exist around the plant were given rice husk mulch, while the temperature range around the plants by applying the rice straw mulch and rice husk mulch was 26.74 0 C at an altitude of 110m above sea level, 28.28 0 C in an altitude of 400m above sea level and 25.04 0 C at an altitude of 1350 m above sea level. According to Dainello F.J et al (2009), the use of rice husk mulch and rice straw mulch on the cultivation of cabbage in hot climates will support faster crop harvest time than the use of solid and plastic mulch. But even better is rice husk mulch, it is due to the nature of rice husk mulch more nests than rice straw mulch. The soil moisture under the mulch nest is lower than the soil moisture under dense mulch.

7,64
Note : The Number that Accompanied by letter is similar to the similar rows are not significantly different at HSD 5% Test.

The Wet Weight of Crop
Effect of rice straw mulch treatments able to produce the highest crop wet weight and significantly different from those without mulch varieties KK Cross altitude 110 meters above sea level (lowlands) of 1226.67 g equivalent to 49 ton ha -1 exceeds the production the description, but not different rice husk mulch. It is suspected of rice straw mulch able to maintain micro-climatic conditions (soil temperature) so that helps plants absorb nutrients properly. The condition has also been proved by Edyta Koesterna (2014) who found their real effect of rice straw mulch 20 ton ha -1 compared with no straw mulch on the observation of wet weight of broccoli planted at different times. Furthermore, rice husk mulch provides the highest wet weight crop varieties altitude of 400 meters above sea Grand 11 (middle plains) of 1125.00 g equivalent to 45 ton ha -1 and was significantly different from other treatments. These results suggested that the ability of mulch to retain soil temperature and moisture better than rice straw mulch at medium altitude. It can be seen in the field that rice husk mulch cover more equal than rice straw mulch on the experimental plot. Biological research results Erita et al., (2010) found that rice husk mulch real influence on all components of the production of maize crops were planted at an altitude of 500 m above sea level.
Treatment without mulch altitude of 1350 meters above sea level it produces a wet weight of the highest crop varieties Grand 11 amounted to 1055.67 g equivalent to 42 ton ha -1 but not significantly different from other Journal of Natural Sciences Research www.iiste.org ISSN 2224-3186 (Paper) ISSN 2225-0921 (Online) Vol.7, No.4, 2017 46 mulch treatments. This indicates that at high altitude the temperature range in treatment without mulch seen in figure 1 is able to donate the proceeds to the Grand 11 varieties better than the temperature in other mulch treatment. Weight loss wet crop in cold regions, especially at higher elevations have also been raised by Rodriquez (2015) which states that the cabbage plant that grows in the cold temperature will cause a decrease in the wet weight of the crop by 50%.

232,50
Note : The Number that Accompanied by letter is similar to the similar coloum are not significantly different at HSD 5% Test.

The Crop Volume
The highest crop volume (985.25ml) is contained in rice straw mulch treatment at an altitude of 110m above sea level, at an altitude of 400m above sea level the highest crop volume (831ml) is contained in the rice husk mulch treatment and at an altitude of 1350m above sea level the highest crop volume (984, 83 ml) is on treatment without mulch.

The Total of Plant Dry Weight
The high total dry weight of cabbage plants (Table 8) planted at an altitude of 400m above sea level using a mulch of rice husk indicates that the use of mulch can keep the moisture in the soil where plants grow in the lowlands so as to generate a total weight of cabbage plants are high, the main varieties in accordance with the terms grew desired. According to Noorhadi and Sudadi (2003) quoted by Nurheni Vitello and Nurunnajah (2010) the air and soil moisture, the temperature of air and soil plants, and each relating to realize the optimal environmental conditions for plants. As stated by (Wade et al. 1983 andHarith, 2000) that the mulch of rice straw on the soil surface in addition to functioning as an organic material, it can also improve the physical, chemical and biological soil in order to obtain the resistance of nutrients and water, improve soil structure, lowering the temperature of the soil, reducing excessive evaporation, reduce weeds and reduce erosion while straw mulch with its nature that easily weathered thus improving soil fertility.

CONCLUSION
The KK Cross variety has weighs crop of 1226.11g (49 ton ha -1 ) heavier than the other varieties at an altitude of 110m above sea level. At an altitude of 400m above sea level the Grand 11 variety produce weight crop of 1125.00g (45 ton ha -1 ) heavier than the other varieties. Furthermore, at an altitude of 1350m above sea level Grand 11 variety produces weight crop of 1055.56g (42.2 ton ha -1 ) heavier than the other varieties. Rice straw mulch on Grand 11 variety is better (1081.44ml) in producing the volume of crop compared to other treatments.