Morphological Characterization of Weedy Rice Populations from Different Regions of Asia

Abstract

Weedy rice produces a low number of grains per plant and is considered undesirable in cultivated rice fields. It spreads rapidly because of its high phenotypic plasticity and seed shattering. We used the RID14 marker to identify the genotypes governing red and white pericarp color in weedy rice. We then evaluated 18 characters of 199 weedy rice accessions (5 rice-growing regions in Asia) and 24 of cultivated rice as control, and analyzed them using coefficients of variation, principal component analysis, and cluster analysis. Our results showed that weedy rice accessions and cultivated rice populations from different regions of Asia were significantly different in one or more of their morphological characteristics. Weedy rice significantly differed from cultivated rice in plant height at vegetative growth phase, and in pericarp color and seed shattering during the reproductive growth phase. According to principal component analysis, weedy rice populations were significantly separated from cultivated rice in North China, Korea, Southeast Asia, Korea, and South China. We used principal component analysis and cluster analysis to categorize weedy rice populations into 3 main groups: Group 1 from Korea and Northern China; group 2 from Southern China and Southeast Asia; and group 3 from Eastern China. This study established an index for morphological characteristics of weedy rice to facilitate its identification the fields, which are expected to provide a theoretical basis for weedy rice infestation control in Asia.

Morphological variation, distribution and relationship of weedy rice (Oryza sativa L.) in Peninsular Malaysia

“…Most morphological traits of weedy rice in this study showed an intermediate form between wild and cultivated rice (Figure 5), which is in line with other reports (Rathore, Singh, Kumar, & Chauhan, 2016; Sudianto et al, 2016; Zainuddin, Azmi, & Othman, 2010; Zhang et al, 2017). This also suggests that wild Oryza and elite cultivars genetically contribute to the complexity of Malaysian weedy rice (Song et al, 2014; Sudianto et al, 2016).…”

The New Is Old: Novel Germination Strategy Evolved From Standing Genetic Variation in Weedy Rice

“…Genomic sequencing and genetic diversity analyses have shown that the weedy rice populations from northeastern China are strongly associated with japonica rice cultivars and those from eastern China with indica rice cultivars, suggesting the independent feralization events occurred with distinct cultivated progenitors in different regions (Cao et al, 2006 ; Qiu et al, 2017 ). In addition to genetic divergence, morphological variations in hull color, awn length and color, grain length/width ratio, etc., have also been reported within and among populations (Zhang et al, 2017 ). Nevertheless, a notable feature that is shared by the weedy rice from eastern and northeastern China is that their seeds do not have primary dormancy.…”

Review: Potensi Weedy Rice (Oryza sativa F. Spontanea) untuk Menjawab Tantangan Penyediaan Sumber Gen Penting dalam Perakitan Tanaman Tangguh Iklim

“…Ciri morfologi dari weedy rice sangat berfariasi dari berbagai negara, di Malaysia mayoritas aksesi weedy rice berwarna coklat dan berbulu (Sudianto et al, 2016), warna pericarp aksesi weedy rice di Asia (Asia tenggara, Korea, China) bervariasi yaitu ada yang berwarna putih, coklat cerah, coklat spot, coklat, dan merah. Dari total aksesi 36, terdapat 11 berpericarp putih, 2 coklat dan 23 merah (Zhang et al, 2017).…”