Sugarcane
selection for resistance to glufosinate herbicide
Kanyawatana Sirivechapan.
Kasetsart University,
Bangkok, 10900.
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Glufosinate resistance in
sugarcane was developed by whole plant and cell culture selection. Fifteen of sugarcane clones were
planted in the field according to a factorial design in RCB to compare the
different genotypes and four levels of glufosinate application (0, 0.50, 1.00,
and 1.50kg ai/ha). The effects of
glufosinate on the physiological response to crop visual injury, plant height,
fresh weight and dry weight were measured. The degree of tolerance was evaluated at 5, 10, and 14 days
after application. It was
demonstrated that KPS 96-8-5, U-thong 3 and KPS 96-16-07 tended to tolerate the
herbicide at 1.00 kg ai/ha, while K 8-42 and K 10-69 were the most susceptible
clones. Cell culture selection was
attempted using callus culture and suspension culture induced from young tight
furled leaves of the three tolerant sugarcane clones. The callus and suspension cells were cultured on MS-modified
medium. Using a stepwise selection
with increasing concentration of glufosinate at 10-8 –10-5
M, the cell from KPS 96-8-5 resist to 10-5 M glufosinate was
obtained through cell suspension culture.
It was referred to as 10-5 M glufosinate-resistant sugarcane
cell; this indicates the resistant index of resistant cell was 4,750 fold more
resistant than normal cell. The
resistant cell was used for biochemical mechanism studies, glutamine synthesis
(GS) activity assay and ammonia accumulation. Activity of GS enzyme of the resistant cell was about 2.33
fold higher than that of the normal cell at 25 hours after treatment (HAT). At 25 HAT, the ammonia accumulation of resistant cell was
lower than that of normal by about 4.4 fold. Furthermore, the 10-5 M glufosinate-resistant
sugarcane cell had no cross-resistance to other herbicides such as glyphosate,
imazethapyr and primisulfuron.
Glufosinate resistance