EFFECT OF INCORPORATION OF SUGARCANE TRASH ON CANE PRODUCTIVITY AND SOIL FERTILITY

Transcription

1 s.b: Jadhav EFFECT OF INCORPORATION OF SUGARCANE TRASH ON CANE PRODUCTIVITY AND SOIL FERTILITY 1 S. B. Jadhav Agricultural Science Technology Vasantdada Sugar Institute, Pune, Maharashtra (India) ABSTRACT Field experiments studying the effect of incorporating sugarcane trash in the soil on its fertility as well as on cane productivity were conducted at the Sugarcane Research Station, Padegaon (Maharashtra, India) from Incorporation of chopped or unchopped sugarcane trash in the soil supplemented with 8 kg urea, 10 kg single superphosphate and 1 kg cellulosedecomposing fungal culture per ton of trash increased cane yield by 12.8 tlha over the control. Chopped and unchopped trash gave similar results with respect to cane yield and growth parameters. Organic carbon content in the soil improved from 0.66 to 0.74 % with the incorporation of trash. Similar trends were noticed for available NPK, thereby enhancing the availability of nutrients. Keywords: Sugarcane, trash management, organic manures, cane yield, soil fertility, India. INTRODUCTION Maharashtra is a major sugar-producing state of India; however, declining cane yield in most of its areas over the last few years is causing concern among cane growers. The average cane yield, which was approx. 90 tlha in the season decreased to about 81 t/ha in (Anon. 1993). Inadequate use of organic manures is one of the main causes of declining cane yield and soil fertility. Furthermore, most farmers cannot afford to use expensive inorganic fertilizers to meet the nutf-ient requirements of the cane crop. On the other hand, with the development and release of high-yielding cane varieties, disposal of residues (e.g., trash) is becoming a serious problem in intensive sugarcane cultivation. This leafy residue discarded at the time of harvest is from 8-10 tlha and contains 4.65% koisture, 0.40% nitrogen, 0.13 % phosphorus and 0.60'%-~otash and &0&46% organic carbon. The 4.5 million t of cane trash generated every year in Maharashtra is generally disposed of by burning in the fields; thus a potential source of OM (nutrient) is,thus lost. The nutrients and OM present in trash can be recycled in the soil either by cornposting or direct incorporation into the soil (Gaur 1986, Shinde et a1 1984b). This not only increases the yield of the first crop but also leaves the soil more fertile after the harvest. There is immense potential for increasing cane production by improving the supply of plant nutrients through the incorporation of trash in the soil. In view of the huge quantities of cane trash available locally, it was decided to ' investigate this waste material as a source of OM for increasing cane productivity and soil fertility, as well as prevent its wasteful disposal. MATERIALS AND METHODS Field experiments were aimed at studying the effect of incorporating trash in the field on cane production and soil fertility. The experiments were conducted for three consecutive crop seasons ( at the Sugarcane Research Station, Padegaon. The experimental treatments were replicated three times in a randomized block design. Gross and net plot sizes were 7.20 x 7.50 m and 4.80 x 5.50 m, resp. Treatments were as follows: T, = Chopped trash Q 2.5 tlha T, = Unchopped 5.0 tlha T, = Chopped trash Q 5.0 tlha T, = Unchopped trash 67.5 tlha T, = Chopped trash Q 7.5 tlha T, = Farm yard manure 5 tlha) T, = Unchopped 2.5 tlha T, = Check (no trash) All treahnknts except T, and T, included urea (8 kglt of trash), single superphosphate (10 kglt of trash) and decomposing culture (1 kglt of trash). The field was laid out into ridges and furrows with a row spacing of 1.20 m for cane planting. Chopped and unchopped trash was placed evenly in the furrows as per treatment; and then the required quantity of urea, single superphosphate (SSP) and decomposing cultures were spread over the trash for hastening the composting process and also for enhancing microbial activity in the soil. The trash was then covered with soil by convesting the ridges into furrows with a ridger. One month after irrigating the furrows, CO 740 was planted at a rate 104

2 Agriculture: Agronomy of 25,000 three-eye budded setts per ha in the Adsali season (July-Aug.). The recommended doses of fertilizer (400 + kg N, 170 kg P20, and 170 kg K20/ha) were applied uniformly in all the plots. Nitrogen was applied in four splits; P and K, two splits. The mixed decomposing fungal culture consisting of five cellulolytic organisms (viz., Aspergillus awarnori, Penicillium chrysogenum, Trichoderma viride, Trichurus spiralis and Chaetorniurn abuense) was used for.quick decomposition of trash. Observations on germination and tillering were recorded during the growth phase; while data on height, girth, millable cane, yield and quality of cane with commercial cane sugar (CCS) were recorded at harvest. Cane samples were taken at random for the quality study. The soil samples collected before planting and at harvest were analyzed for organic carbon, total N, available P and K content by standard methods (Black et a1 1965). The microbial popwon of all treatments was estimated by soil ation and Warcup's soil plate methods (Warcup, 1950). Data were pooled for three years (Tables 1-4). RESULTS AND DISCUSSION The pooled data for three crop seasons show that cane and CCS, microbial population and nutrient levels are influenced sigtllticantly by the incorporation of trash in the soil. The data in Table 1 reveal that the incorporation of trash at 7.5 th-both chopped and unchopped-increased cane yield significantly from 141 to 154 tlha and 152 tlha, resp. Sirmlarly, the CCS increased by 22.2 % and 14.6 % with chopped and unchopped trash, resp., over the control. The chopped trash at all rates produced marginally higher yield and CCS than unchopped trash, ranging from and tlha, resp., over the control. The application of 5 t FYMIha yielded 9.2 tlha more cane than the control. Similar trends were observed for the growth parameters; viz., germination, tillering ratio, millable cane and cane girth (Table 2). Thus the incorporation of cane trash in the field along with urea, SSP and decomposing cultures enhanced crop growth as reflected in improved cane productivity. The initial CIN ratio (120: 1) of trash was lowered to less than 20: 1 after trash decomposition in the soil. Similar results with various crops were also reported by Bhardwaj & Gaur 1985, Rasal et a1 1987, Jadhav et a and Shinde et a1 1984a. Variation with respect to juice quahty, Brix, sucrose and purity was not simcant nor was there any adverse effect on juice quality due to incorporating trash in the field (Jadhav et al 1985, Rasal et a1 1987). Table 3 shows that the microbial population increased significantly, particularly wit6 the addition of 7.5 tlha chopped and unchopped trash along with urea, SSP and decomposing cultures at earthing up and at harvest. It was observed that the microbial population increased at earthing up atid at harvest due to improved biological activities in the soil when incorporating trash. OM supplemented with N and P further enhanced the microbial population. Similar results were obtained by Parkhe & Shinde 1981, Gaur & Mukherjee, 1980 and Rasal et al 1988, Soil analyses data initially and after harvest (Table 4) show that ph and EC values were lower due to trash incorporation. Organic carbon content in the soil improved with increasing (up to 0.74%) levels of trash. Nitrogen and P are essential for growth and effectiveness of the decomposing fungi (Subba Rao 1984). Therefore the addition of urea, SSP and decomposing cultures must have lmteiied the process of decomposition and made nutrients from trash readily available to the crop. It was also observed that the availability of N (up to 249 kglha) and P (up to 46 kglha) iu the soil increased considerably with the incorporation of trash over the control (no trash). This indicated that the addibon of OM to the soil could modify its reaction, enhance the availability of nutrients (Rasal et a1 1986, 1989) and ultimately increase crop productivity and soil fertility. CONCLUSIONS Incorporation of chopped or unchopped trash in the field at 7.5 tlha with 8 kg urea, 10 kg SSP and 1 kg decomposing culture per ton of trash before planting not only increased cane yield but also built up soil properties and microbial activities, which favorably influenced cane productivity and soil fertility.

3 Table 1. Effect of trash incorporation on cane and CCS yield (tlha). Sr Pooled mean Increase smx control No. Treatments Yield CCS Yield CCS Yield CC Yield CCS Yield CCS 1 Chopped 2.5 t/ha Chopped 5.0 t/ha Chopped 7.5 t/ha Unchopped 2.5 t/ha Unchopped 5.0 t/ha Unchopped 7.5 t/ha FYM@ 5.0 t h Check (no trash) SE +_ LSD at 5%

4 Table 2. Effect of incorporating trash on growth parameters and juice quality. Millable Germination Tillering Millable Cane girth cane Brix Sucrose Purity Treatments % Ratio caneslha (cm) ht. (cm) % % % TI T T T TS T T, At earthing wtage I At harvesting stage microbial I Treatment Azoto- Actino- P-solubilizin~ Azoto- Actino- P-solubilizing population

5 S.B. Jadhav Table 4. Effect of trash incorporation on soil properties at harvest.' Organic EC carbon Available nutrients &g/h& Treatments ph (pmhoslcm) (%) N P,O, K,O T, T T T T T T T, Initial analysis 'Initial CIN ratio of trash was 120: 1, which after decomposition decreased to < 20: 1 REFERENCES Anon. (1993). Ann. rept. on sugarcane crop. Sugarcane Research Sta., Padegaon, MPKV, Rahuri, 84 p. Bhardwaj, K.K.R. & Gaur, A.C. (1985). Recycling of organic wastes. ICAR Pub., New Delhi. pp Black, C.A. : Evans, D.D. ; White, J.L. ; Ensrninger, L.E. & Clark, F.E. (1965). Methods of soil analysis, Part 11. Agronomy 9, ASA Inc. Madison, WI. Gaur, A.C. (1986). Recent trends in recycling of crop residues. J. Maharashtra Agric. Univ. 1 l(2): Gaur, A.C. & Mukherjee, D. (1980). Recycling of organic matter through mulch on crop yield and its effects on chemical and microbiological properties. Plant and Soil 56(2): Jadhav, S.K.; Jadhav, J.J & Jadhav, S.B. (1985). Effect of sugarcane trash incorporation on yield of cane (Co 740). 35th DSTA:A63-A68. Parkhe, D.D. & Shinde P.A. (1981). Recycling of sugarcane trash-i. Direct incorporazion into field soil. J. Maharashtra Agric. Univ. 6(3): Rasal, P.H; Kalbhor, H.B. & Patil, P.L. (1988). Effect of cellulolytic and phosphate solubilizing fungi on chickpea growth. J. Indian Soc. Soil Sci. 36: Rasal, P.H. ; Shingte, V.V. & Patil, P.L. (1986). A study on the incorporation of sugarcane trash on the nodulation and yield of Gram. J. Maharashtra Agric. Univ. 11(3): Rasal, P.H.; Shingte, V.V. & Patil, P.L. (1987). A study on direct incorporation of sugarcane trash on yield of sugarcane. J. Environ. Biol. 8(4): Rasal, P.H.; Shingte, V.V. & Pati1,P.L. (1989). Effects of sugarcane trash on crop yields and soil properties. J. Maharashtra Agric. Univ. 14(1): Shinde, P.S.; Jangale, G.D.; Bangar, S.G.; Shingte, V.V. & Patil, P.L. (1984a). Influence of incorporation of sugarcane trash on yield of wheat and gram. Maharashtra Sugar 10(2): Shinde, P.B.; Jangale, G.D.; Shingte, V.V. & Patil, P.L. (1984b). Recycling of cane trash in sugarcane production. Ind. Sugar 34(9): Subba Rao, N.S. (1984). Biofertilizers in agriculture. Oxford & IBH Pub. Co., New Delhi, 186 p. Warcup, J.H. (1950). The soil plate method for isolation of fungi from the soil. Nature 166:

6 EFECTO DE LA JNCORPORACI~N DE LOS RESIDUOS SOBRE LA PRODUCTIVIDAD DE LA C ~ Y A FERTILIDAD DEL SUELO S.B. Jadhav Agricultural Science Technology Vasantdada Sugar Institute, Pure, Maharashtra (India) Agriculture: Agronomy RESUMEN Experimentos dirigidos a estudiar el efecto de la incorporacidn de 10s residuos de cafh sobre la fertilidad y producci6n heron realizados entre 1887 y 1990 en la estacibn de experimentos en Padegaon (Maharastra, India). La incorporacidn de residuos picados y enteros aportaron a1 suelo 8 kglha de urea, 10kgIha de superfosfato simple y 1 kglha de material celular descompuesto por cada tonelada de residuos y se awnent6 la producci6n de cafia en 12.8 tlha. Los residuos picados y enteros produjeron efectos sirnilares sobre el desarrollo y producci6n de la cab. El contenido de carbon0 organico en el suelo se increment6 de 0.66 a 0.74% con la incorporaci6n de 10s residuos. Tendencia similar se obtuvo con el nitr6gen0, f6sforo y potasio disponible.