Effects of Organized Soil Cultivation on Yield and Quality of Tomato in Greenhouse

Effects of Organized Soil Cultivation on Yield and Quality of Tomato in Greenhouse Zhi-bin Zhang and Chao-xing He Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences Zhongguancun South Street 12, Beijing 100081 China Keywords: Greenhouse, tomato, organized soil, agricultural waste, fruit yield, quality Abstract Organized soil cultivation is a kind of culture that mixed by decomposed agricultural waste such as corn stalk, wheat straw, mushroom residue or saw dust, decomposed manure and soil in definite ratio. In this experiment, 10 treatments of organized soil mixture were conducted to cultivate tomato in greenhouse. The results showed that the yield and quality of tomato in most of organized soil treatments were increased than soil control. The better formulas of organized soil mixture for greenhouse tomato had been selected as T2, T6 and T8, which were made from organic manure and soil, corn straw and sawdust or mushroom residue according the ratio of 1:2:1. In these treatments, the yield of tomato increased 24% more than that of soil control, the quality of tomato fruit also increased. INTRODUCTION Organic food and vegetable market increased quickly in the world since 1980s, organic cultivation techniques were important for organic food production (Xi and Qin, 2002). In Mainland China, the total area for vegetable production was 17.4 million ha in 2003 including 1.8 million ha protected vegetable cultivation. China was affluent in varies agricultural waste such as wheat straw, maize stalk and rice straw etc. About 600 million tons crop straw produced every year, but only 30% of the straw were utilized. Most of straws were burnt which not only caused serious air pollution, but also made natural resources wasted. How to make use of the agricultural waste becomes a very important problem in China. Recent years, experiments on mixing decomposed straw with organic manure for vegetables cultivation in greenhouse had been done, and some results had been reported (He et al., 2004, Qi et al., 2003). Organized soil cultivation is to use agricultural waste such as corn stalk, wheat straw, mushroom residue or saw dust and decomposed manure mixed with soil in definite ratio to cultivate vegetables. This technique can not only efficiently decrease disease ratio of vegetable root, but also prevent the pollution of chemical fertilizer leak to groundwater in soil cultivation. The technique can use the agricultural wastes to produce the organic food with low cost, which also can save water and improving soil structure. In this paper, the effects of different organized soil mixtures on the tomato yield and quality were studied in greenhouse. Optimized formulas of organized soil for greenhouse tomato were put forward. MATERIALS AND METHODS Organized soil cultivation experiment was carried in plastic multi-greenhouse in Institute of vegetables and flowers, Chinese Academy of Agricultural Sciences (Beijing, China) from 2001 to 2002. Brick groove cultivation was introduced. The width of groove was 0.48m, the height of groove was 0.2m, and the groove length for each plot was 2.0m. At the bottom of groove, plastic films were spread to insulate organized soil mixtures from the ground. The organized soil mixtures were made of difference crop straw with decomposed manure. The crop straw should be crushed and decomposed. Each cube meter mixture appended 10kg poultry manures, 0.25kg CO(NH 2 ) 2 and 1kg Ca(H 2 PO 4 ) 2 H 2 O, then mixed evenly to load into the groove before transplanting. 10 treatments of organized soil mixtures were designed as follows (v/v): T1. 25% manure + 75% wheat straw;t2. 25 %manure + 75% saw dust;t3. 25% manure + 75% Proc. IC on Greensys Eds.: G. van Straten et al. Acta Hort. 691, ISHS 2005 305

corn stalk;t4. 25% manure + 75% mushroom residue;t5. 25% manure + 50% corn stalk + 25% wheat straw;t6. 25% manure +50% corn stalk + 25% saw dust;t7. 25% manure + 50% corn stalk + 25% peat;t8. 25% manure + 50% corn stalk + 25% mushroom residue;t9. 25% manure + 50% corn stalk + 25% vermiculite T10. 37.5% manure + 50% corn stalk + 12.5% wheat straw ash. Soil and soilless substrate controls were used as follows: CK1. 25% manure + 37.5% peat + 37.5% vermiculite;ck2. 25% manure + 75% soil;ck3. 50% manure + 50% soil; CK4. 75% manure + 25% soil. Manure was air-dry mixture of 80% organic fertilizer and 20% soil (v/v). Tomato (Lycopersicon esculentum Mill) cultivars were Zhongza No. 9. The seeds were germinated in Jan. 16 th, and transplanted in March 18 th. The row spacing of plant is 0.4m and interplant spacing is 0.28m. Drip irrigation system was used above organized soil surface. The first top-dressing is used as follow ratio (v/v) 75%dry poultry dung +25%compound fertilizer (N15%, P 2 O 5 15%, K 2 O 15%), which was carried out in April 15 th and once every 30 days (each slots 1kg). The growth point of plants was removed when tomato grew eight trusses fruit and the experiment was terminated on 2 nd August. The yield and fruit quality of tomato were investigated. Height and stem diameter of plant were measured in first flowers stage and last harvest stage. The bulk density of organized soil mixture was measured with cutting ring method. General porosity was calculated according to reference (Liu, 2001). PH value of mixture was determined by using Model LEIZ -3C PH Meter. Electrical conductivity and salinity of organized soil mixture were measured with HANNA salinity Meter (made in Portugal). Organic materials content was measured by potassium dichromate method. Soluble total sugar content in fruit was measured with the anthracenone method. VC content of tomato was tested with Phosphomolybdate Photoelectric Colorimetry. Single fruit weight, yield and blossom end rot (BER) were calculated with chosen ten plants from each plot. RESULTS Physical and Chemical Properties of Main Organic Materials The analyzed results showed in table 1. All organic materials were weak alkaline with PH >7.0 except peat. Based on bulk density of materials, all organic materials belong to light substrates. The favorable porosity of substrates would be useful for plant to absorb nutrition and develop root system. All substrates are with 0.02~0.56 range of large porosity/small porosity, which indicated that they all had better water-holding characters. The salinity of manure and wheat straw ash is above 1.4 g/l, much higher than any other materials, so the ratio of them should be lower in organized soil mixture. Organic material contents were above 80% in every agricultural waste, so agricultural wastes would provide fine physical structure for root growth. Effects on the Plant Growth The increments of tomato plant height were showed in Fig.1. Most of organized soil treatments have more plant height increments than soil controls (CK2, CK3, CK4). T2 and T9 treatments had the most increment, T1 and T8 had the least, similar to soil controls. The stem diameter changes among treatments were also different (Fig. 2). The increment of T2 was the largest, and T1 was the least. Most of organized soil treatments had more stem diameter increments than soil controls (CK2,CK3,CK4). It seemed that organic materials was beneficial to root growth, so it was necessary to make use of reasonable organic material and to made up of suitable organized soil mixtures. Effects on Tomato Yield There were obvious differences between different treatments on tomato yield (Table 2). The yields of treatments T2, T6, T8, T9 had significantly higher than soil controls because of increase single fruit weight. Their yield near to the yield of soilless 306

(CK1), but the cost was greatly reduced than CK1. So organized soil mixtures with corn stalk, organic fertilizer, sawdust and mushroom residue had notable yield increase effect. They could entirely substitute the traditional irreproducible substrate materials, such as peat and vermiculite. The yield of treatments T4, T5 and T7 were similar to that of soil controls. The yield of treatments T1, T3 and T10 were much lower than soil controls because the lower single fruit weight. It might be the bulk ratio of wheat straw, or corn stalk in mixture exceeded 50%, the bulk densities of mixture was too puff or too high salinity to plant growth. Blossom end rot (BER) of fruit in T4, T8, CK4 and CK3 were much higher than others. These mixtures with high salinity organic matters such as manure or mushroom residue, which made plant roots difficult to absorb water from substrates and induced the occurrence of BER disease. Effect on Fruits Quality of Tomato The organized soil cultivation can obviously improve fruit quality. Table 3 showed that lycopene contents of tomato in most organized soil treatments were much higher than that in soil control (CK2). The highest lycopene content of tomato was in the CK1. The soluble solids content of tomato in T2, T6 and T8 were higher than that in controls. The reducing sugar contents of tomato in T2, T3, T8 and CK3 were higher than that in others. The crude protein contents in T2, T8 and CK1 were the highest. The VC contents of tomato in T2, T4, T6, T10, CK3 and CK2 were higher than others. In summarize, the integrate quality of tomato in treatments of T2, T6, T8, T10 and CK3 were better than others. The suitable organized soil mixtures could produce higher quality of tomato. The high quality in T10 and CK3 might attribute to the higher salinity. Physical and Chemical Properties Alterations of Organized Soil Mixtures All organized soil mixtures appeared weak alkaline before planting (Table 4). Soil Controls had stronger alkaline with ph >8, and their ratio of large porosity to small porosity were significantly lower than any other organized soil mixtures. Organic material contents declined after planting for all treatments. Although organic material content of organized soil mixtures decreased more than that in soil, they had higher organic materials content than soil controls after planting. The bulk densities of the composed of manure and soil were 0.95~1.16g/cm 3. The organized soil mixtures were in the scope of 0.28~0.56g/cm 3. The bulk density of all treatments increased during cultivation, but bulk density of organized soil treatments increased 4 times more than soil controls because it might be decomposition of organic materials by microbe. The salinity of organized soil mixtures was lower than soil. The salinity of all the treatments reduced during growth, the salinity of soil decreased to 34.2%. Total porosity of all treatments declined during planting, which may due to the sediment effect by irrigation and gravity. DISCUSSION It was suggested that the best physical property of organized soil mixtures were as follows: bulk density about 0.5g/cm 3, PH 6.8, total porosity about 60%, large porosity/small porosity was about 0.5, conductivity ratio about 2.0ms cm -1 (Liu, 2001;Duan et al., 2002;Roe et al.,1997). The bulk density, total porosity and salinity of soil controls were all out of the suitable range, so the tomato growth and yield in soils seemed worse than that in organized soil mixtures. The T2, T6 and T8 indicated that their physical properties were more near to the suitable physical structure with the stable physical properties, which in favor of root development. T2 treatment had the best yield and quality because it had the similar physical properties to soilless control (CK1). The yields of the treatments T1, T10 and soil controls were very low, which might result from high PH, high salinity or dramatically physical structure alteration. The most economic formula of organized soil in these treatments might be T8, which consisted of manure, corn stalk and mushroom residue with ratio of 1:2:1. 307

During tomato growth, the large porosity/small porosity of all the treatments increased, so the water retention of all treatment decreased. The organic material content also decreased, whereas the bulk density of organized soil increased during cultivation. If reused organized soil for vegetable cultivation, it was necessary to loosen organized soil and replenish organic material for increase proportion of small porosity and organic content. Organized soil mixtures might have many positive effects to growth and yield of tomato. Jiang (1998) had reported that tomato cultivation with organic substrate of peat: vermiculite = 4:6 could increase reducing sugar and Vc content and reduce organic acid content compared with nutrition fluid cultivation. Study on organic matter of reed residue as substrate also showed that quality such as contents of soluble solids, soluble sugar and VC in tomato fruit could improved compared with rockwool culture(guo and Li,2000). In this experiment results also showed that content of soluble solids and lycopene had increased more in organized soil cultivation than soilless control, but the cost of organized soils was much lower than the cost of soilless substrate. When the volume ratio of wheat straw, or corn stalk in organized soil mixtures exceeded 50% such as in T1,T3, the bulk density of organized soils was so low that the plant was difficult to absorb nutrient. The high salinity of soil controls might have negative effects to plant growth. Organized soil cultivation was a cheap organic vegetable cultivation technique; it can make the best use of the agricultural waste such as straw, stalk, manure and soil. It achieved the aim of low-cost organic vegetable production, natural resource use and environment protection together. During planting, the components of organized soil mixtures were changing with the time owing to the decomposition of organic materials and manures. The organized soil mixtures could continually release nutrient, the released quantity was changeable in different cultivation conditions (Jiang et al.,1996; Raviv et al., 1998; De Bootdt et al., 1972). How to maintain relatively steady chemical and physical properties including the water and nutrient application method in the organized soil cultivation were still need to research in future. The best mixtures of organized soil were also need to study. ACKNOWLEDGEMENTS Thanks to Minister of Sciences and Technology of China for financial assistance (National high technology research projects No. 2004 AA247010 and 2002 AA243031). Literature Cited De Bootdt, M. and Verdonck, O. 1972. The physical properties of the substrates in horticulture. Acta Hort. 26:37-44. Duan Chongxiang, Yu Xiangchang and Cui Xigang. 2002. Study on organic culture media in greenhouse. Journal of Chinese Agricultural engineering. 18:193-196. Gao Xinhao, He Chaoxing and Zhang Zhibin et al. 2004. Study to the effects of different organized soil on Cole growth in greenhouse. Northern Horticulture. (1):46-47. Guo Shirong and Li Shijun. 2000. A study on the technique of vegetable soilless culture with organic. Jounal of Shenyang Agricultural University. 31(1):89-92. Jiang Weijie, Zheng Guanghua and Bai Gangyi. 1996. The technique of organic ecotype soilless culture and its nutrient physiological basis. Acta Horticulture Sinica. 23 :139-144. Jiang Weijie. 1998. Application of some agricultural wastes as peat replacement in soilless culture. Journal of Chinese Agricultural engineering, 12(Supplement):177-180. Liu Shizhe. 2001. Modern Practically Soilless Cultivation Techniques. China Agricultural Press, Beijing. Qi Weiqiang, He Chaoxing and Zhang Zhibin et al. 2003. Preliminary study to the effects of stalk organic composite on tomato growth in greenhouse. Shaanxi Agricultural Science. (6):3-5. Raviv, Reuvenni and Zaidman. 1998. Improved medium for organic transplants. Biological-Agriculture-and Horticulture.16:53-64. 308

Roe, N.E., Stoffella, P.J. and Graetz, D. 1997. Composts from various municipal solid waste feedstock affect vegetable crops. J. Amer. Soc Hort. Sci. 122:433-437. Xi, Yunguan and Qin Pei. 2002. Organic Agriculture Ecological Engineering. Chemical Industry Press, Beijing. Tables Table 1. Physical and chemical properties of organic materials. Materials PH Bulk density (g/cm 3 ) Salinity (g/l) Total porosity Large/small porosity Total N Total P (mg/kg) Total K Organic content Peat 6.60 0.50 0.23 62 0.06 1.37 1400 0.39 43.6 Vermiculite 8.04 0.42 0.04 68 0.02 0.06 823 1.43 0.53 Corn stalk 7.25 0.12 0.49 60 0.56 1.36 1700 1.17 84.4 Wheat straw 7.86 0.09 0.35 54 0.54 0.85 573 1.31 83.9 Wheat straw ash 9.46 0.24 1.43 75 0.03 0.59 3000 3.50 20.6 Sawdust 7.30 0.28 0.24 84 0.07 0.36 279 0.17 87.8 Mushroom residue 7.11 0.39 0.50 45 0.24 2.21 3900 1.02 82.8 Manure 8.17 0.85 1.48 40 0.06 0.78 4600 0.60 22.2 Table 2. Tomato yield composite and blossom end rot incidence ratio of treatments. Treatment Fruits per plant Average fruit Weight (g) Yield/plant* (kg) Increase ratio Ratio of BER incidences CK1 25.6 149 3.81a 27.5 8.0 T1 23.1 110 2.54e -15.2 8. 0 T2 26.3 145 3.81a 27.4 5.0 T3 22.3 118 2.62de -12.3 3.0 T4 24.8 127 3.14c 4.9 21.0 T5 23.6 124 2.92cde -2.4 4.0 T6 25.8 143 3.70ab 24.0 6.0 T7 22.2 136 3.02cd 1.0 6.0 T8 25.2 143 3.60ab 20.2 12.0 T9 24.1 146 3.51b 17.4 2.0 T10 21.4 120 2.57e -14.0 7.0 CK2 23.3 128 2.99cde 0 4.0 CK3 22.4 121 2.71cde -9.2 28.0 CK4 22.0 123 2.71cde -9.4 22.0 Significant difference under 5% level 309

Table 3. Effects of treatments on nutrient matter contents of tomato fruits. Treatment Reducing sugar Crude protein VC (mg/100g) Soluble solids Lycopene (mg/100g) CK1 3.86 0.89 12.8 5.8 56.4 T1 3.97 0.63 12.1 5.8 34.4 T2 4.55 0.95 16.9 6.4 43.4 T3 4.26 0.71 13.2 5.8 41.3 T4 3.94 0.72 14.1 5.6 37.7 T5 3.87 0.70 13.4 5.6 39.1 T6 3.55 0.65 14.0 6.2 47.0 T7 3.55 0.62 12.2 5.0 43.8 T8 4.03 0.87 13.6 6.0 48.5 T9 3.53 0.62 11.6 5.2 38.2 T10 3.95 0.75 15.0 5.8 47.0 CK2 3.44 0.78 15.5 5.2 34.4 CK3 4.13 0.76 17.1 6.2 44.7 CK4 3.52 0.55 12.6 5.0 42.2 Table 4. Changes of physical properties of different substrates from seeding to harvest. Treatments Large/small porosity Pre Post PH Organic material Bulk density (g/cm 3 ) Salinity (g/l) total porosity Pre Post Pre Post Pre Post Pre Post CK 1 0.55 1.58 7.53 30.8 22.1 0.56 0.93 0.57 0.33 59 36 T 1 0.42 0.55 7.94 68.5 13.7 0.28 0.87 0.63 0.56 50 26 T 2 0.57 0.54 7.52 71.4 36.2 0.42 0.60 0.55 0.46 73 51 T 3 0.44 0.79 7.48 68.9 14.4 0.30 0.92 0.74 0.64 55 45 T 4 0.19 0.95 7.37 67.7 15.9 0.47 0.51 0.75 0.78 50 49 T 5 0.34 0.68 7.63 68.7 15.0 0.30 0.92 0.70 0.44 53 40 T 6 0.31 0.88 7.49 69.7 29.9 0.34 0.86 0.68 0.31 61 32 T 7 0.31 0.68 7.32 58.7 25.0 0.40 0.84 0.67 0.29 55 42 T 8 0.35 1.19 7.45 68.5 22.8 0.37 0.83 0.74 0.61 51 38 T 9 0.30 0.79 7.68 47.9 12.9 0.38 0.84 0.63 0.12 57 33 T 10 0.31 1.87 7.87 53.1 13.4 0.41 0.86 0.74 0.23 54 22 CK 2 0.12 1.42 8.10 7.96 6.65 1.16 1.39 1.30 0.82 31 25 CK 3 0.10 1.42 8.12 12.7 7.21 1.05 1.32 0.98 0.73 41 27 CK 4 0.08 1.08 8.15 17.5 10.8 0.95 1.20 1.43 0.89 40 28 Pre-pre planting; Post-post planting 310

Figurese Plant height increment from flowering to harvest (cm) 180 160 140 120 100 80 60 40 20 0 CK1 T2 T4 T6 T8 T10 CK3 Treatment Fig. 1. Influence of treatments on plant height of tomato. 0, 9 0, 8 Stem diameter increment (cm) 0, 7 0, 6 0, 5 0, 4 0, 3 0, 2 0, 1 0 CK1 T1 T2 T3 T4 T5 T6 T7 T8 T9 T10 CK4 CK3 CK2 Treatment Fig. 2. Influence of treatments on plant stem diameter. 311

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