REDUCED TILLAGE SYSTEMS FOR HEAVY COASTAL CLAY SOILS IN THE GUYANA SUGAR INDUSTRY

Transcription

1 REDUCED TILLAGE SYSTEMS FOR HEAVY COASTAL CLAY SOILS IN THE GUYANA SUGAR INDUSTRY N.W. Friday, H.B. Davis, A.D. Dey, A. Simon and P. Mc Farlane Guyana Sugar Corporation Inc.

2 BACKGROUND In Guyana sugar cane is cultivated along the coastal plain on flat lands with levels varying between 0.3 m below to a maximum of 2.1 m above mean sea level Soils have high clay contents, are difficult to cultivate and require several passes of the implement to produce a suitable seed bed In addition, a significant proportion of these soils have swelling and high water retention properties, which can further curtail land preparation activities and extend the re-entry entry time of machines into fields following a rainfall event (Davis et. al. 2005).

3 BACKGROUND CONT D In Guysuco tillage is usually consists of several passes with a plough and/or harrow over the entire bed width These approaches to tillage can be costly, and time consuming. They also involve significant soil manipulation that can increase susceptibility to erosion Wide cambered beds have facilitated mechanization in harvesting and husbandry operations and have permitted application of reduced tillage activities.

4 BACKGROUND CONT D The Paraplow developed by Howard (with the NCAE Silsoe) in the 1980 s s became the primary tillage tool in Guyana and demonstrated its propensity to loosen compacted clay soil (Dey, et al., 1997) For this reason the principle of the angled sub-soil soil implement became the basis of the design of locally fabricated reduced tillage implements in Guysuco One such device, the Rut Repairer consists of a combination of components to perform cultivation, soil loosening and scarifying, all in a single pass.

5 PRIMARY OBJECTIVE Further evaluate minimum/reduced tillage operations as a standard land management practice in Guysuco using mainly locally fabricated implements

6 SECONDARY OBJECTIVES Evaluate the impact of reduced tillage systems on sugarcane growth and yields soil physical properties and plant root development the productivity indices of machines performing the various tillage systems The impact on the performance of various cane varieties planted in single or double row culture (2007 trial)

7 METHODOLOGY(2004 trials) Two trials were established at Le Ressouvenir,, La Bonne Intention estate The 1 st trial was established at LR 29 and 31 1 st crop The 2 nd trial was established at LR 11 to 27 2 nd crop Both trials were conducted on Whittaker series soil (Tropic Fluvaquent), mapping unit 37 (FAO, 1967; Smith, 1983) The varieties D89138 and DB7869 (standard) were planted in the two trials respectively Both trials were severely affected by floods in January 2005 and 2006 to the extent that the first trial was heavily supplied and the second replanted in March 2005.

8 Sequence of operations 1 st trial Tillage system No Tillage Strip Tillage Strip Tillage Full-width Tillage Sequence of operation 1. Plant slot formation 1. Disc harrow 2. Spring tine 3. Plant slot formation 1. Paratill implement 2. Plant slot formation 1. Paraplow 2. Tandem harrow 3. Spring tine 4. Plant slot formation

9 Sequence of operations 2 nd trial Tillage system Sequence of operation Zero or No tillage Strip tillage (cane row) Strip tillage (inter-row) Full-width Tillage Full-width Tillage 1. Plant slot formation 1. Paratill implement 2. Strip harrow 3. Plant slot formation 1. Paratill implement 2. Strip harrow 3. Spring tine 4. Plant slot formation 1. Paraplow 2. Tandem harrow 3. Spring tine 4. Plant slot formation 1. Disc plough by 32 harrow 3. Spring tine 4. Plant slot formation

10 METHODOLOGY (2007) The trial was established at LR st crop Rains curtailed all mechanical operations and as such a number of fields had to be planted manually only 1 replicate of the trial design was achieved Data collection and evaluation were done from a single replication comprising three fields, each with one tillage system, namely full-width tillage, strip tillage or no tillage Superimposed in the full-width and strip tillage systems respectively are two row-planting methods (single or double), while the no tillage field comprised only single-row planting

11 Four different cane varieties were further superimposed in each row-planting method. Primary tillage in full-width was done with the paraplow In reduced tillage, operations were restricted to the cane lines -primary operation was achieved with two paraplow shanks placed 50cm apart on the paraplow tool bar.

12 Sequence of operations 3 rd trial Tillage system Implement/ description Sequence of operations No tillage none Plant slot formation Strip tillage Paraplow with 2 para tines 50 cm apart 1. Para plough 2. Strip harrow Full-width tillage Paraplow with 3 para tines 90 cm apart 1. Para plough 2. Harrow 3. Spring tine

13 2-6 Disturbed area

14 Tractor wheels Cane plant Disturbed area

15 Dual-row planting activities Manual laying of tops Furrow opening Covering of canes

16 ROW PLANTING METHODS Single-row planting Double-row planting

17 Howard Paraplow Rut Repairer

18 Specifications of Rut Repairer Description Details No.of discs 4 No.of para-tines 4 shanks slanted at 45 0 Para-tines depth of 30 cm work No. of spring-tines Overall width Working width Weight Power requirement Productivity 12 coiled shanks 3.0 m 1.8 m 1315 kg 120 Horse power 0.8 ha/hr

19 Reduced tillage with Rut Repairer

20 STRIP HARROW Modified and fabricated at ARC, Guysuco

21 RESULTS & DISCUSSION (Plant root volume g/l 1st trial) Tillage system 3 Months postplanting (0 60 cm) Post 1R (0 15 cm) No tillage Strip tillage with harrow Strip tillage with Rut Repairer Full-width tillage with paraplow

22 Soil dry bulk density 1st trial Tillage system (0 30 cm) 3 Months postplanting (30 60) Post 1R (0 15) No tillage Strip tillage with harrow Strip tillage with Rut Repairer Full-width tillage with paraplow

23 Soil resistance (MPa) 9 weeks post planting 1st trial Tillage system (0 30 cm depth) (30 60 cm depth) No tillage Strip tillage with harrow Strip tillage with Rut Repairer Full-width tillage with paraplow

24 Cane yields (T/Ha) 1 st trial Tillage system Plant 1R cycle 2R cycle No tillage Strip tillage with harrow Strip tillage with Rut Repairer Full-width tillage with paraplow Prob % CV

25 Cane yields (T/Ha) 2 nd trial Tillage system Plant cycle 1 R cycle No tillage Strip tillage with Rut Repairer in the cane row Strip tillage with Rut Repairer in the inter-row Full-width tillage with paraplow Full-width tillage with disc plough Prob % CV

26 Soil resistance & dry bulk density 3 rd trial (9 mts) Tillage system Soil Resistance (MPa) Soil dry bulk density (g/cm 3 ) Full-width Strip Zero

27 Stalk population per 1 metre-row 3 rd trial (9 months) Full-width tillage Strip tillage No tillage Variety Single row Double row Single row Double row Single row D DB D DB Mean

28 Equipment productivity - Tillage Activity Description Rate (hrs/ha) Full width tillage Para plough, harrow, & cultivate 3.4 Reduced tillage Strip para tine & strip harrow 1.92

29 CONCLUSIONS Results obtained are consistent with those of earlier studies - no adverse effects of reduced tillage on soil physical properties or cane yields Reduced tillage showed a reduction in operational costs for land preparation Row-planting method did not impact significantly on the stalk population in any of the tillage systems

30 Thank you!