Management strategies for fertigation of sweet cherry Denise Neilsen and Gerry Neilsen Summerland Research and Development Centre, Summerland, BC, Canada V0H 1Z0 MCAREC Sweet Cherry Symposium, Feb. 4 th, 2016 Dalles, OR, USA
Changes in production systems sweet cherry Mazzard, F12/1 rootstock, 6m x 6m Gisela 5,6 rootstock, 1.2-2.5m x 4-5m
Root length (km/m 2 ) Tree fruits have very small but efficient root systems Root length density at crop maturity 14 12 10 8 6 4 2 Min Max 0 Apple Kiwifruit Peach Pear Sweet (from Buwalda 1993) Cherry Length of root per area of soil surface (cm/cm 2 ) 10,000 1000 100 10 herbaceous grasses herbaceous Non-grasses woody plants 1 tree fruits
Increasing tree density gives more water & nutrient management options
Why use fertigation Compact root systems and micro-irrigation offer good opportunities for controlled application of nutrients Precision nutrition can reduce inputs and improve fruit quality In irrigated production systems - water management controls nutrient availability
Fertilizer Sources Can use most N sources except Pressure solutions or anhydrous ammonia since they raise water ph and precipitate calcium. Cannot use calcium nitrate with phosphates or sulfates. Can use KCl, KNO 3, K 2 SO 4. Chelates of micronutrients: Zn, Fe, Mn.
Avoid these Combinations! Phosphates and calcium (unless ph < 4). Mg added to Ca or ammonia unless acidic. Ammonium thiosulfate in acid or basic solutions. Urea Sulfuric Acid and UAN. Micronutrients and phosphates unless: At least 45% polyphosphate, micros are chelated or the solution is acidic. Commercial MAP and DAP in a solution. If in doubt do a compatibility test outside of irrigation system!!
Nitrogen very mobile in soil and water allows flexibility in application but difficult to control
Nitrogen when to apply?
Sources of N for growth N removed in fruit and pruning? N stored in leaves N withdrawn from leaves N remobilized for new growth Internal N cycling N stored in woody tissue N removed in pruning
Leaf N (%dw) Contribution of winter storage N and C to tree performance in sweet cherry 4 3 2 1 N2 N1 Harvest Lapins/Gisela5 Leaf strip (Sept 15) N withdrawal to storage 0 Jul Aug Sep Oct 2004
Fruit number Yield (kg/tree) Contribution of winter storage N + C to production in sweet cherry 3000 2500 Lapins/Gisela5 Fruit Number Yield 2005 2006 2005 2006 25 20 leaf stripping decreased fruit number & yield 2000 1500 1000 500 15 10 5 fruit bud development/set highly dependent on stored N + C 0 no yes no yes no yes no yes 0 Leaf stripping Leaf stripping in Fall 2004
Fruit number Yield (kg/tree) Contribution of winter storage N + C to production in sweet cherry 3000 2500 Lapins/Gisela5 Fruit Number Yield 2005 2006 2005 2006 25 20 leaf stripping decreased fruit number & yield 2000 1500 1000 500 15 10 5 fruit bud development/set highly dependent on stored N + C 0 no yes no yes no yes no yes 0 Leaf stripping Leaf stripping in Fall 2004
sap flow ml/cm 2 TCSA Timing of sap flow in the spring 200 Sap flow 150 100 side green green tip tight cluster open cluster first white first full bloom 50 0 80 85 90 95 100 105 110 115 120 Day of the year Sap flow Sap flow water uptake starts around first white in sweet cherry Likely determines onset of rapid N uptake Granier type thermal dissipation probe
Nitrogen - How much?
N removal in cherry fruit Cv/rootstock N inputs kg/ha Spacing (m) Age (yr) N removal kg/ha Skeena/Gi6 42 2x4 5 ~30 Cristalina/Gi6 42 2x4 7 ~45 Lapins/Gi5 30 4x4.5 12 ~20 *Skeena/Gi6 50 1.5x4 4 ~20 *Skeena/Gi5 50 1.5x4 4 ~20 *Skeena/Gi3 50 1.5x4 4 ~11 *UFO
Nitrogen too much of a good thing? Lapins/Gi5 experiment Fertigation treatments N (8 weeks daily post full bloom) 1. Low (42 ppm) ~63 kg/ha 2. Medium (84 ppm) ~126 kg/ha 3. High (168 ppm) ~ 254 kg/ha
TCSA (cm 2 ) Yield (kg/tree) Tree growth- Lapins/Gisela 5 200 150 100 50 a Low N Medium N High N a b 50 45 40 35 30 25 20 15 10 5 0 **** *** Low N Medium N High N 2000 2001 2002 2003 2004 2005 Very high N decreased tree growth and yield Neilsen et al. 2007. HortScience 42
Fruit size-lapins/gisela 5 N rate 2000 2001 2002 2003 2004 2005 g/fruit Low 12.6 11.0 10.0 11.2 9.7 14.9 Medium 12.0 10.0 9.0 9.9 10.1 14.4 High 12.3 9.6 9.0 8.5 9.4 13.8 ns * * ** ns ** N Rate: Low ~ 63 kg/ha; Medium ~126 kg/ha; High ~ 254 kg/ha Neilsen et al. 2007. HortScience 42
55 cm How precise can we be? Measurement of water and nutrient leaching using PCAPs (wick samplers) 75 cm Drip emitter M/S 25 cm 50 cm Surface of PCAP sampler box
N loss (g/tree) Water loss (L/tree) Neilsen et al. 2002 HortTechnology 12 Water and N drainage reduced by irrigation scheduling in Gala/M.9 200 100 0 4 3 2 1 0 b a Scheduled to meet ET Unscheduled (fixed rate) b a fertigation period b a May June July Aug. Sept. Oct-May May b a water losses high under unscheduled irrigation during periods of low ET water and N losses related during fertigation period irrigation scheduling keeps N in the root zone
Summary N Good N management depends on increasing N availability by Retention of N in root zone using good water management practice Timing applications to demand post bloom for root uptake and fall foliar N to augment winter storage Cherry and apple trees can require relatively small N inputs
Phosphorus and potassium Much less mobile than N Spatially targeted applications required
Phosphorus effects on sweet cherry Fertigated P (20g P as 10-34-0) Increased cumulative yield over 3 years Increased fruit size 1 year in 3 Increased stem pull force 2 years in 3 Reduced soluble solids 2 years in 3
Summary P Mobility and availability of P can be improved by fertigation immediately after bloom P availability can also be increased by the use of organic amendments and mulches P applications increased yield and fruit quality in several apple and sweet cherry cultivars
Fruit K (mg/100g FW) Leaf K (%) Leaf and fruit K - Lapins/Gisela 5 3 2 1 0 250 200 150 ** *** * ** *** LEAF ** *** **** **** FRUIT **** **** K fertigation (microsprinkler) did not affect leaf or fruit K conc. (data not shown) Leaf and fruit K reduced under drip irrigation, likely due to soil K leaching and restricted roots 100 2000 2001 2002 2003 2004 2005 Drip Microsprinkler Neilsen et al. 2007. HortScience 42
Summary K Coarse textured soils under drip irrigation can develop K deficiency Mobility and availability of K can be improved by fertigating K in a number of different formulations K applications under conditions where soils are approaching deficiency do not increase susceptibility to bitter pit in apples
Leaf B (ppm) Leaf B concentration in apple in response to application method 140 120 100 80 60 40 20 Gala Fuji Fiesta Spartan No B applied a b c d a a b b B sprayed 0.336 g B/tree/year a b a b B fertigated a b a b 0.175 g B/tree/year a b c b a b c b 0 1992 1993 1994 1995 1996 1997 1998 Year 30
NC-140 Sweet Cherry Project - Nutrition Nutrient Form Application duration Application rate (g/tree) N 15.5-0-0 Daily 6 weeks after bloom 16.5g N/tree 27.5 kgn/ha P 10-34-0 One day after bloom 20g P + 13.5g N/tree 33 kgp + 22.5 kgn/ha K 0-0-60 Daily for 6 weeks starting 4 weeks after bloom B Solubor (20.3% B) Daily for 6 weeks starting 4 weeks after bloom 20g K /tree 33 kg K/ha 0.17gB/tree 0.28 kg/ha
Thank you