James Gerik* 1 ,Sadikshya Dangi 1,2 , and Husein Ajwa 2 1 USDA-ARS; 2 University of California-Davis; 3
James Gerik*1,Sadikshya Dangi1,2, and Husein Ajwa2
1USDA-ARS; 2University of California-Davis; 3
Calla Lily Approximately 300 acres of Calla are planted in the
spring each year.
The crop cycle last approximately 18 months and the crop goes dormant during the winter.
Bulbs (rhizomes) are harvested at the end of the crop cycle and flowers may be cut during the second summer.
All acreage is fumigated before planting (QPS exemption).
Objectives Past experiments have shown that calla lily can be
successfully grown using alternative fumigants. These have included combinations of chloropicrin (Pic), 1, 3-dichloropropene (1, 3-D), and potassium metam (K-Pam). An experiment is being conducted to determine the lowest effective rates that these chemicals can be successfully used to grow this crop.
Treatments The plots were approximately 500 feet long and
consisted of raised beds 72 inches wide.
The main plots were fumigated with either InLine (1, 3-D 60.8%, Pic 33.3%) or Pic-Clor 60 EC (Pic 56.7 %, 1, 3-D 37.1%) or left untreated.
Both fumigants were applied at three rates: 20, 17, and 14 gallons per acre.
Treatments One week after the initial fumigation the sub-plots
were fumigated with one of four rates of K-Pam: 0, 28 34, or 40 gallons per acre.
All fumigants were applied through five drip irrigation tapes on the surface of the beds beneath virtually impermeable film.
0
500
1000
1500
2000
2500
3000
3500
4000
control IL-14 IL-17 IL-20 PC-14 PC-17 PC-20
Fumigation Treatment
Fusarium oxysporum CFU/g
0
28
34
40
K-
0
200
400
600
800
1000
1200
control IL-14 IL-17 IL-20 PC-14 PC-17 PC-20
Fumigation Treatment
Pythium spp. CFU/g
0
28
34
40
K-Pam
0
20
40
60
80
100
120
140
control IL-14 IL-17 IL-20 PC-14 PC-17 PC-20
Nu
mb
er
/ I
m b
ed
le
ng
th
Fumigation Treatment
Stand Count
0
28
34
40
K-Pam
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
control IL-14 IL-17 IL-20 PC-14 PC-17 PC-20
Dis
ea
se R
ati
ng
(0
-5)
Fumigation Treatment
Disease Rating 7/21/2012
0
28
34
40
K-Pam
Control
InLine 14
InLine 17
InLine 20
PicClor 14
PicClor 17
PicClor 20
Conclusions The populations of F. oxysporum were not significantly
reduced at any rates of the primary fumigants.
The fumigants did a much better job in reducing populations of Pythium spp. compared to F. oxysporum; we have observed this before in past experiments when using these fumigants.
Conclusions The stand of calla lily was not affected by the soil
treatments.
Disease control was better with InLine compared to Pic-Clor.
Disease control improved with the higher K-Pam treatments
The trial will continue until the end of 2012 when the bulbs will be harvested and disease incidence and yield results collected.
Thanks to the Pacific Area-Wide Methyl Bromide Alternative Program for Funding for the Last Five Years.