Presence of the HPPD Inhibitor Sensitive 1 Gene and ALSS653N Mutation in Weedy Oryza sativa Sensitive to Benzobicyclon.

Chad Brabham,Jason K Norsworthy,Fidel González-Torralva

doi:10.3390/plants9111576

Chad Brabham, Jason K Norsworthy + Show 1 more

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https://doi.org/10.3390/plants9111576

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Abstract

Benzobicyclon has shown varying results in controlling weedy rice, including those with imidazolinone (IMI) resistance. Tolerance to benzobicyclon in cultivated japonica rice, but not indica or aus-like cultivars, is conferred by a fully functional HPPD Inhibitor Sensitive 1 (HIS1) gene. Herein, a diagnostic Kompetitive Allele Specific PCR (KASP) assay was developed to predict the HIS1 genotype of weedy rice plants from 37 accessions and correlated to their response to benzobicyclon in the field. Two-thirds of the 693 weedy rice plants screened were tolerant to benzobicyclon (371 g ai ha−1, SC formulation) at 30 days after treatment (DAT). Thirty-four percent of plants were homozygous for the HIS1 allele and 98% of these plants exhibited field tolerance. However, the his1 genotype did not always correlate with field data. Only 52% of his1 plants were considered sensitive, indicating that the single nucleotide polymorphisms (SNPs) chosen in the KASP assay are not a reliable tool in predicting his1 homozygous plants. In an additional experiment, 86% of the 344 plants with at least one copy of the ALSS653N trait harbored a HIS1 allele, suggesting fields infested with IMI herbicide-resistant weedy rice are unlikely to be controlled with benzobicyclon.

Highlights

In rice (Oryza sativa L.) fields worldwide, weedy rice is a troublesome weed that can cause economic losses by reducing grain yield and/or grain quality [1,2]
Only out of the accessions tested had similar tolerant in the field experiment and, on a plant level, 98% of all homozygous hydroxyphenylpyruvate dioxygenase (HPPD) Inhibitor Sensitive 1 (HIS1) plants classifications. These results indicate that the single nucleotide polymorphisms (SNPs) chosen in the Kompetitive Allele Specific PCR (KASP) assay are not a reliable tool in were biologically tolerant to benzobicyclon
We have linked the susceptibility of those weedy rice accessions to benzobicyclon

Summary

Introduction

In rice (Oryza sativa L.) fields worldwide, weedy rice is a troublesome weed that can cause economic losses by reducing grain yield and/or grain quality [1,2]. Season-long interference of weedy rice at 2 or 40 plants m−2 was found to reduce the grain yield of different cultivars by 7 to 19% and 61 to 87%, respectively [3,4]. Weedy rice and cultivated rice are the same species, and selective chemical control of weedy rice in cultivated rice is extremely difficult. Cultural practices such as crop rotation, stale seedbed, water seedings, or transplanting instead of direct-seeding are some of the methods used around the world to deter weedy rice infestations [5].

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