Irrigation scheduling and efficient use of water in potato crops

Transcription

1 Research Review Irrigation scheduling and efficient use of water in potato crops Submitted April 1998 M A Stalham, E J Allen & S R Gaze Cambridge University Farm 1999

2 British Potato Council Any reproduction of information from this report requires the prior permission of the British Potato Council. Where permission is granted, acknowledgement that the work arose from a British Potato Council supported research commission should be clearly visible. While this report has been prepared with the best available information, neither the authors nor the British Potato Council can accept any responsibility for inaccuracy or liability for loss, damage or injury from the application of any concept or procedure discussed. Additional copies of this report and a list of other publications can be obtained from: Publications Tel: British Potato Council Fax: Nash Court publications@potato.org.uk John Smith Drive Oxford Business Park South Oxford OX4 2RT Some of our reports, and a list of publications, are also available on the internet at

3 CONTENTS Page Irrigation scheduling and efficient use of water in potato crop 8 Introduction 8 Demand 8 Supply 10 Measuring soil water availability and crop water use. 18 Crop response to water availability 28 Tuber Quality 31 Improvements in scheduling practice 35 Conclusions 40 Summary 41 Acknowledgements 42 References 42 3

4 LIST OF FIGURES Figure Title Page 1 Cumulative measured and potential water use in Desiree (Stalham 9 & Firman, 1991). 2 Effect of compaction on rooting depth and maximum limiting soil 14 moisture deficit in Cara (Stalham & Allen, 1995). 3 Varietal differences in rooting depth (Stalham & Allen, 1994) Varietal effects on rate of leaf appearance (Stalham & Allen, ). 5 Effect of time of sampling after emergence on the proportion of 16 total root length in different horizons in irrigated Cara (Stalham & Allen, 1993) 6 Effect of time of sampling after emergence on the proportion of 17 total water uptake from each horizon in irrigated Cara ( Stalham & Allen, 1993). 7 Modelled and measured soil moisture deficits in Maris Piper 19 (Rosenfeld, 1997). 8 Water extraction pattern of uncompacted Maris Piper (Rosenfeld, ). 9 Water extraction pattern of compacted (10 & 40 cm) Maris Piper 21 (Rosenfeld, 1997). 10 Hourly water uptake at different depths measured using the 22 EnviroSCAN capacitance-type probe in irrigated Saturna (Stalham & Gaze,1997) 11 Proportional contribution of water uptake of different horizons 23 measured by the EnviroSCAN during three periods in irrigated Saturna (Stalham & Gaze, 1997, unpublished). 12 EnviroSCAN and neutron probe soil moisture deficits of a 24 commercial crop of Saturna grown by CA Strawson (Farming) Ltd in Norfolk (Stalham, 1996). 13 Neutron probe soil moisture deficits (0-90 cm) from four sites in a 25 commercial 14 EnviroSCAN soil moisture deficits in four plots of Saturna 26 receiving the same rain and irrigation (Gaze & Stalham, 1997). 15 Irrigation distribution pattern of Wright Rain ST110/350TT, 27 raingun / hosereel combination, nozzle size 25 mm. Target application: 22 mm. Conditions: a) Poor. Time: 14-16:00. Wind: 30 km/hr. b) Good. Time: Wind: <5 km/hr/ Mean of three replicates along direction of gun travel (Stalham, 1990, unpublished) 16 Irrigation distribution pattern of Briggs R50 Boom plus Ocmis 28 R4/100/450. Time: Wind: 25 km/hr. Target application: 8mm (Stalham, 1995, unpublished). 17 Evapotranspiration for potato during June-August 1990 and at CUF. Horizontal lines refer to the maximum daily potential ET that can be sustained at SMD s of 10, 25 and 40mm 18 Modelled soil moisture deficits during June-August 1990 at CUF applying 25 mm every 7 days from 1 June, including and excluding 37 4 British Potato Council

5 rainfall. 19 Modelled soil moisture deficits during June-August 1996 at CUF applying 25 mm every 7 days from 1 June, including and excluding rainfall 20 Modelled soil moisture deficits during June-August 1990 and 1996 at CUF applying 25 mm whenever the SMD reached 40 mm from 1 June, including rainfall. 21 Modelled soil moisture deficits from tuber initiation in 1990 and 1996 at CUF applying 8 mm at an SMD of 10 mm during scab control and 25 mm whenever the SMD reached 40 mm thereafter, including rainfall British Potato Council

6 LIST OF TABLES Table Title Page 1 Effect of textural classification on the available water holding 12 capacities at three different soil water potentials. 2 Maximum depths of root penetration for various cultivars 13 3 Effect of variety on ratio of unirrigated :irrigated tuber yield 29 (Stalham & Allen, 1991). 4 Limiting soil moisture deficit (mm) for leaf growth in two 29 contrasting varieties (Stalham & Allen, 1993). 5 Effect of irrigation regime on fresh weight yield (t/ha) of 30 tubers>10mm for three processing varieties (Gaze & Stalham, 1997). 6 Effect of depth of compaction and irrigation regime on tuber yield 31 (t/ha;rosenfeld, 1997). 7 Effect of irrigation regime on severity of common scab(% surface 32 area infected) in at CUF (Stalham & Firman, 1996). 8 Effect of irrigation on silver scurf severity (% surface area) in Desiree over three years (Firman & Allen, 1993) 33 6 British Potato Council