Several studies have expressed concerns about the effects of gene flow from transgenic herbicide-resistant crops to their wild relatives, but no major problems have been observed. This review describes a case study in which what has been feared in transgenics regarding gene flow has actually changed biodiversity and people's lives. Nontransgenic imidazolinone-resistant rice (IMI-rice) cultivars increased the rice grain yield by 50% in southern Brazil. This increase was beneficial for life quality of the farmers and also improved the regional economy. However, weedy rice resistant to imidazolinone herbicides started to evolve three years after the first use of IMI-rice cultivars. Population genetic studies indicate that the herbicide-resistant weedy rice was mainly originated from gene flow from resistant cultivars and distributed by seed migration. The problems related with herbicide-resistant weedy rice increased the production costs of rice that forced farmers to sell or rent their land. Gene flow from cultivated rice to weedy rice has proven to be a large agricultural, economic, and social constraint in the use of herbicide-resistant technologies in rice. This problem must be taken into account for the development of new transgenic or nontransgenic rice technologies.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4947146PMC
http://dx.doi.org/10.1111/eva.12387DOI Listing

Publication Analysis

Top Keywords

weedy rice
20
gene flow
16
rice
12
rice weedy
8
imi-rice cultivars
8
herbicide-resistant weedy
8
weedy
5
evolutionary social
4
social consequences
4
consequences introgression
4

Similar Publications

In order to improve both resistance to lepidopteran pests and resistance to the herbicide imazethapyr in mainstay varieties of the Huang-Huai rice region, Sanming dominant genic male sterile (S-DGMS) rice was used as a platform to facilitate the pyramiding of functional genes and the replacement of the genomic background. Twelve novel lines were developed, each carrying a crystal toxin gene conferring resistance to lepidopteran pests and the allele conferring resistance to herbicide imazethapyr in the background of a mainstay variety. The genomic background of the 12 novel lines was examined using 48 specified molecular markers, and each line carried less than two polymorphic markers relative to the corresponding mainstay variety.

View Article and Find Full Text PDF

To explore the internal factors related to the strong growth and competitive ability of weedy rice during the seedling period, we collected two biotypes of Japonica weedy rice from Northeast China, four biotypes of Indica weedy rice from Eastern China and Southern China, and two biotypes of cultivated rice, Zhendao-8 (ZD-8) and Shanyou-63 (SY-63), which were used as controls in a pot experiment. Under homogeneous garden planting conditions, we measured the vascular bundle size (VBS), vascular bundle number (VBN), leaf thickness (LT), air cavity size (ACS), stomatal size (SS), stomatal density (SD), net photosynthetic rate (Pn) and stomatal conductance (Gs) of the weedy and cultivated rice biotypes. A comprehensive analysis was performed to explore the correlation between the seedling leaf structure and the photosynthetic indices of the biotypes.

View Article and Find Full Text PDF
Article Synopsis
  • Weedy rice, a close relative of cultivated rice, infests fields globally and reduces crop yields, prompting US farmers to adopt herbicide-resistant (HR) rice varieties to combat this issue.
  • The introduction of HR and hybrid rice cultivars changed the dynamics of crop-weed hybridization, allowing for adaptive introgression and altering selective pressures.
  • A study analyzing 178 weedy rice samples showed geographical shifts and genetic mechanisms in response to herbicide selection, revealing the adaptation of weedy rice through diverse genetic pathways.
View Article and Find Full Text PDF

-cinnamoyltyramine (NTCT) has been identified from an allelopathic Vietnamese rice accession OM 5930. This study employed bioassays to analyze NTCT's effects on shoot and root growth of multiple test and weed species. NTCT demonstrated potent inhibitory effects on cress, lettuce, canola, palmer amaranth, timothy, barnyardgrass, red sprangletop, and weedy rice, with increasing concentrations leading to substantial reductions in growth in all species.

View Article and Find Full Text PDF

Bifunctional Phenylalanine/Tyrosine Ammonia-Lyase (PTAL) Enhances Lignin Biosynthesis: Implications in Carbon Fixation in Plants by Genetic Engineering.

Biology (Basel)

September 2024

Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, Department of Ecology and Evolutionary Biology, Fudan University, Songhu Road 2005, Shanghai 200438, China.

Lignin is a key metabolite for terrestrial plants. Two types of aromatic amino acids, phenylalanine (Phe) and tyrosine (Tyr), serve as the precursors for lignin biosynthesis. In most plant species, Phe is deaminated by Phe ammonia-lyase (PAL) to initiate lignin biosynthesis, but in grass species, Phe and Tyr are deaminated by Phe/Tyr ammonia-lyase (PTAL).

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!