Early flowering and rapid grain filling determine early maturity and escape from harvesting in weedy rice

Abstract

Early maturity is an essential factor determining the persistence of weedy rice by contributing to the escape of its seed from being harvested with the rice crop. Both early flowering and shorter grain-filling stages determine early maturity, and flowering is more plastic than grain filling. © 2017 Society of Chemical Industry.

Contrasting patterns of variation in weedy traits and unique crop features in divergent populations of US weedy rice (Oryza sativa sp.) in Arkansas and California

“…Panicle length (cm) 10 Awn length (cm) 11 Grain length (mm) 12 Grain width (mm) 13 Culm diameter (cm) 14 Tillage practice 15…”

“…Being conspecific with cultivated rice makes control of weedy rice difficult because morphological and physiological traits are shared with the crop. Some weeds successfully outcompete the crop or escape management or removal at harvest; for example, enhanced photosynthesis of weedy rice at the seedling stage, early flowering and rapid grain filling determine early maturity and allow competitive dominance of weedy genotypes over cultivated rice . Other weeds adapt to a managed ecosystem with consistent artificial selection through phenotypic mimicry of the cultivated plant .…”

“…Some weeds successfully outcompete the crop or escape management or removal at harvest; for example, enhanced photosynthesis of weedy rice at the seedling stage, early flowering and rapid grain filling determine early maturity and allow competitive dominance of weedy genotypes over cultivated rice. [12][13][14] Other weeds adapt to a managed ecosystem with consistent artificial selection through phenotypic mimicry of the cultivated plant. 15,16 Weedy traits from wild relatives, such as dark hull color, seed shattering, dormancy, pericarp pigmentation and other traits have been implicated in weed success, 6,17,18 but little is known about patterns of morphological, physiological and genetic variation underlying weeds de-domesticated from (and co-occurring with) crop relatives.…”

Integrative hormone and transcriptome analyses underline the role of abscisic acid in seed shattering of weedy rice

“…It competes for nutrients, water, sunlight and other resources with cultivated rice and consequently affects crop production [3,4]. Thus, for example, in China, weedy rice can reduce rice crop yield by 10 % -50 %, and consequently cause serious economic loss [5]. Furthermore, it has many morphological and physiological traits related to weediness, and is strongly characterized by its high seed shattering rate [6,7].…”

The within-field and between-field dispersal of weedy rice by combine harvesters

“…In agro-ecosystems, many forms of human activity can contribute to weed dispersal; weed seeds can be spread with manure used as fertilizer (Dastgheib 1989;Pleasant and Schlather 1994), irrigation water (Dastgheib 1989), and by machinery during soil tillage and harvesting operations (Wiles and Brodahlb 2004). Weedy rice normally disperses its seed by gravity under non disturbed conditions in absence of particular dispersal structures in the seed and by having a relatively large mass (Zhao et al 2017); the wide-range and long-distance dispersal of weedy rice seed by water, wind, and animals is also limited. Previous studies indicated that weed species such as Panicum miliaceum (Mccanny and Cavers 1988), Lolium rigidum (Blanco-Moreno et al 2003), and Avena fatua (Shirtliffe and Entz 2005) could be dispersed widely within a field by combine harvesters during harvesting.…”