Seed potato physiological age and crop establishment

Transcription

1 Seed potato physiological age and crop establishment Juliano Oliveira, Derrick Moot, Hamish Brown Acknowledgements: Lincoln University, Plant & Food Research and Potatoes New Zealand

2 Note: This presentation was made by Prof. Derrick Moot on 6 Nov 2014 in Alexandra at the New Zealand Agronomy Society Annual Conference. It is associated with the following scientific publication: Oliveira, J.S., Moot, D.J. and Brown, H.E Seed potato physiological age and crop establishment. Agronomy New Zealand, 44, XXX-XXX.

3

4 Physiological age Duration Temperature

5 Desiccation Planting

6 Canterbury Temperature (ºC) Haulm desiccation Planting date Haulm dessication Planting date Cool store 0 Feb Apr Jun Aug Oct Date

7 Importance for growers and industry Storage strategies prior to planting Potato processors Potato growers Yield

8 Importance for growers and industry Storage strategies prior to planting Potato processors Potato growers Nº of stems per seed potato Crop establishment

9 Importance for growers and industry Storage strategies prior to planting Potato processors Potato growers

10 Objectives 1. Decouple chronological and thermal effects on physiological ageing. 2. Assess the impact of different storage regimes on crop establishment. 3. Assess the possibility of manipulating the number of stems emerged (potato size).

11 Materials and Methods Cultivars Bondi ( French fry ) High yields Tubers too large for processing < 150 mm Fraser ( Crisps ) Low yield Resistant to cold sweetening < 300 g

12 Experimental design 2 cultivars 4 combinations of storage temperatures 6 planting dates 4 replicates

13 May Jul Sep Nov Jan Mar Storage Regime HL LH ML L Time (days) Code H1L1 H2L1 H3L1 H4L1 H5L1 H6L1 L1H1 L2H1 L3H1 L4H1 L5H1 L6H1 M1L1 M2L1 M3L1 M4L1 M5L1 M6L1 L2 L3 L4 L5 L6 L Cd 1440 Cd 1998 Cd 2502 Cd 3060 Cd 3600 Cd 846 Cd 738 Cd 684 Cd 738 Cd 720 Cd 774 Cd 378 Cd 600 Cd 786 Cd 954 Cd 1140 Cd 1320 Cd 180 Cd 180 Cd 180 Cd 180 Cd 180 Cd 180 Cd H = 20 C M = 8 C L = 2 C

14 Planting date Time (days) Aug 80 Oct Jan 234 HL LH ML L Code H1L1 H2L1 H3L1 H4L1 H5L1 H6L1 L1H1 L2H1 L3H1 L4H1 L5H1 L6H1 M1L1 M2L1 M3L1 M4L1 M5L1 M6L1 L2 L3 L4 L5 L6 L7 May Jul Sep Nov Jan Mar

15 All spouts removed prior to planting

16 At each sowing: Potatoes were grown at 20 C in the dark for ~4 weeks then harvested

17 Time of emergence (days) Cultivar Treatment Planting dates 7/8/2012 7/9/2012 5/10/2012 5/11/2012 5/12/2012 7/1/2013 HL NIL Bondi L LH ML Mean HL NIL Fraser L LH ML Mean Cultivar P<0.02 Temperature treatments ns Planting date P<0.02

18 Time of emergence (days) Effect of cultivar: Bondi emerged about 2 days earlier than Fraser Effect of planting date: Later planting dates = Earlier emergence No emergence for the tubers which accumulated 3600 Cd during storage (HL) Temperature: Storage temperature had no effect on potato emergence

19 Number of stems emerged Bondi At the commercial sowing date stem number was unaffected by storage regime ( Cd) Fraser At the commercial sowing date stem number was able to be manipulated by pre-planting storage conditions No. above-ground stems/tuber 'Bondi' HL LH ML L 'Fraser' 0 Aug Sep Oct Nov Dec Jan Feb Aug Sep Oct Nov Dec Jan Feb Planting date Planting date

20 Number of nodes formed (Development) Why was there no effect of storage regime on node number at the October sowing? Cd Nodes aboveground / stem 'Bondi' HL LH ML L Aug Sep Oct Nov Dec Jan Feb Aug Sep Oct Nov Dec Jan Feb Planting date 'Fraser' Planting date

21 Number of stems emerged Why didn t the tubers stored for 3600 Cd emerge? No. above-ground stems/tuber 'Bondi' HL LH ML L Chronological age 'Fraser' 0 Aug Sep Oct Nov Dec Jan Feb Aug Sep Oct Nov Dec Jan Feb Planting date Planting date

22 Number of stems emerged 3600 Cd seed After storage (pre-sprout removal) After harvest (4 weeks after planting)

23 Shoot DM after 4 weeks (Growth) Average shoot DM (g) 'Bondi' HL LH ML L 'Fraser' Warmer temperatures = More shoot DM 0 Aug Sep Oct Nov Dec Jan Feb Aug Sep Oct Nov Dec Jan Feb Planting date Planting date

24 Conclusions High storability plasticity was found for the two main crops. Bondi 2400 Cd Fraser 1500 Cd The number of stems emerged per seed can be manipulated during storage. Bondi = Chronologically Fraser = Chronologically and Thermally Electricity Electricity No need to use refrigerated storage. Electricity Electricity Electricit