Methods to Promote Germination of Dormant Setaria viridis Seeds

Acta horticulturae, 2018

The expansion of the kiwifruit industry in South Africa has led to increasing demand in the new improved species, Actinidia arguta and Actinidia chinensis, with smaller and sweeter fruits than the commonly grown Actinidia deliciosa. Seed dormancy had been an obstacle in the successful seedling establishment of the two Actinidia species thus, the effect of gibberellic acid (GA3) and cold stratification (CS) on in vivo seed germination was studied. In the GA3 experiment, non-stratified seeds were imbibed in dH2O (control) and GA3 solutions (500, 1000, 2000 and 2500 ppm) for 24 h at ambient temperature. For the CS experiment, seeds of both species were stratified on moist filter paper at 4°C for 14, 28, 42 and 56 days, while seeds kept at ambient temperature served as a control. Seeds from different GA3 and CS treatments were sown in seedling trays filled with moistened vermiculite and kept under controlled conditions. Data on seedling performance variables, namely, germination percentage (GP), mean germination time (MGT), germination rate (GR) and germination index (GI) were subjected to ANOVA and then lines of the best fit. Imbibing kiwifruit seeds for 24 h in solutions of different GA3 concentrations resulted in no germination of A. arguta seeds and a very poor germination (1%) of A. chinensis seeds. In the cold stratified seeds, treatment effects were significant (p≤0.05) in A. chinensis, except for A. arguta seeds. In A. chinensis, the optimum CS duration and performance values were 37 days and 16% for GP, 34 and 15 days for MGT, 33 days and 0.04 seedling day-1 for GR and 39 days and 0.13 seedling day-1 for GI, respectively. Results of this study suggested that GA3 had no positive effect, whereas CS had a promising effect on in vivo seed germination in both Actinidia species.

The architecture of a plant affects its ability to compete for light and to respond to environmental stresses, thus affecting overall fitness and productivity. Two components of architecture, branching and height, were studied in 182 F 7 recombinant inbred lines (RILs) at the vegetative, flowering and mature developmental stages in the panicoid C 4 model grass system, Setaria. The RIL population was derived from a cross between domesticated S. italica (foxtail millet) and its wild relative S. viridis (green foxtail). In both field and greenhouse trials the wild parent was taller initially, started branching earlier, and flowered earlier, while the domesticated parent was shorter initially, but flowered later, producing a robust tall plant architecture with more nodes and leaves on the main culm and few or no branches. Biomass was highly correlated with height of the plant and number of nodes on the main culm, and generally showed a negative relationship with branch number. However, several of the RILs with the highest biomass in both trials were significantly more branched than the domesticated parent of the cross. Quantitative trait loci (QTL) analyses indicate that both height and branching are controlled by multiple genetic regions, often with QTL for both traits colocalizing in the same genomic regions. Genomic positions of several QTL colocalize with QTL in syntenic regions in other species and contain genes known to control branching and height in sorghum, maize, and switchgrass. Included in these is the ortholog of the rice SD-1 semi-dwarfing gene, which underlies one of the major Setaria height QTL. Understanding the relationships between height and branching patterns in Setaria, and their genetic control, is an important step to gaining a comprehensive knowledge of the development and genetic regulation of panicoid grass architecture.

2016

Setaria viridis (green foxtail) is a C4 annual grass species in the same subfamily as maize and sorghum. It is a widespread weed, and its small size, rapid life cycle, large seed production, and sequenced genome make the species a useful model crop for cereal and biofuel grasses . We are interested in the genetic regulation of growth and branching in this species and have produced mutants that are affected in these traits. Because growth varies over the lifetime of the plant, we are using measurements at multiple time-points to understand how variation in growth leads to different morphologies at maturity.

Botanical Journal of the Linnean Society, 2019

Setaria viridis, a genetic model for C4 monocots, has potential to provide information of relevance for plant biotechnology, contributing to an understanding of how genetic engineering can affect phenotype and agricultural production. The BBCH growth scale for the A10.1 accession of S. viridis consists of a detailed phenotypic analysis process, based on defined growth stages. Measurements of morphological attributes complementing the scale were also made, supporting the identification of growth and development stages. Phenotypic stages were grouped into three major stages of development: vegetative (BBCH 0 to 4), reproductive (BBCH 5 to 8) and senescence (BBCH 9). Observation and interpretation of the growth and development data of accessions A10.1 and Ast-1 showed that the former presents phenotypic homogeneity, which makes it suitable for the construction of the BBCH-scale and improves our understanding of the phenology of this model plant. This methodological framework facilitate...

Rangeland Ecology & Management, 2012

Smoke or heat from fire can act as a cue that affects seed germination. We examined germination responses of 10 plant species (six forbs, two shrubs, two grasses) native to the southern High Plains in the United States, to smoke, heat, and their interaction in a laboratory experiment. Smoke treatments were applied by soaking seeds in 1:5, 1:10, or 1:100 (v/v) Regen 2000H smoke solution for 20 h. Heat treatments were applied by placing seeds in an oven at 50uC or 80uC for 5 min. Nine species responded to smoke, heat, or both. Results showed that smoke can enhance, inhibit, or not affect seed germination. Germination capacities of Gutierrezia sarothrae (Pursh) Britton & Rusby and Astragalus crassicarpus Nutt. were promoted by 1:5 and 1:100 dilutions of smoke water, respectively; Coreopsis tinctoria Nutt., G. sarothrae, Salvia reflexa Hornem., Digitaria ciliaris (Retz.) Koeler, and Panicum virgatum L. were inhibited by high and/or moderate concentrations of smoke water either in germination percentage or in mean germination time. Germination percentage of Solanum elaeagnifolium Cav. increased following an 80uC heat treatment. Interaction effects between smoke and heat on germination also were detected. Smoke and heat treatments might be useful as management tools for promoting or suppressing specific target species of shortgrass prairie communities in future habitat management. El ahumado o calor del fuego puede actu ´a como agente que afecta la germinacio ´n de semillas. En un experimento de laboratorio, examinamos la respuesta de diez especies nativas (seis hierbas, dos arbustos, y dos pastos) de las Planicies del Sur de los Estados Unidos al ahumado, calor y las interacciones. En los tratamientos de ahumado se remojaron semillas con la solucio ´n de ahumado Regen 2000H en 1:5, 1:10, o 1:100 (v/v) por 20 horas. Los tratamientos de calor se aplicaron poniendo semillas en un horno a 50uC o 80uC por 5 minutos. Nueve especies respondieron al ahumado, calor, o ambos. Los resultados mostraron que el ahumado podrı ´a mejorar, inhibir o no afectar la germinacio ´n. Las capacidades de germinacio ´n de la Gutierrezia sarothrae (Pursh) Britton & Rusby y Astragalus crassicarpus Nutt. fueron estimuladas por la dilucio ´n de 1:5 y 1:100 ahumador agua, respectivamente; Coreopsis tinctoria Nutt., G. sarothrae, Salvia reflexa Hornem., Digitaria ciliaris (Retz.) Koeler, y Panicum virgatum L. fueron inhibidas por alto y/o moderada concentracio ´n de ahumador agua en ambos porcetaje de germinacio ´n o en tiempo promedio de germinacio ´n. El porcentaje de germinacio ´n de Solanum elaeagnifolium Cav. aaumento despue´s del tratamiento de calor a 80uC. Se detectaron efectos de interacciones entre ahumado y calor en la germinacio ´n. Los tratamiento de ahumado y calor podrı ´an ser u ´tiles como herramientas de manejo para promover o suprimir especies claves especificas de las comnidades de las praderas de pastos cortos en futuros manejos de ha ´bitat.

Here we report that a synthesised form of a naturally occurring chemical (a butenolide, 3-methyl-2H-furo[2,3-c]pyran-2-one) found in smoke can stimulate seedling emergence of the economically important weed species Avena fatua L. (Poaceae), Arctotheca calendula (L.) Levyns (Asteraceae), Brassica tournefortii Gouan (Brassicaceae), and Raphanus raphanistrum L. (Brassicaceae) under field conditions at rates equivalent to 2-20 g/ha a.i. The butenolide also stimulates germination of freshly collected seeds from wild populations of these species, as well as those of Sisymbrium orientale L. (Brassicaceae), Hordeum leporinum Link (Poaceae) and Echium plantagineum L. (Boraginaceae) under laboratory conditions, consistently greater than that of smoke water. Experiments using B. tournefortii seeds collected from several locations across Western Australia and in different growing seasons found that these factors significantly influence the butenolide response, implying a role of the maternal environment in seed germination/dormancy characteristics. This research highlights the potential of butenolide as an agent for broad acre weed control and land restoration.

Crop & Pasture Science

Context Avena sterilis subsp. ludoviciana (wild oats) is one of the major winter weeds of the Northern Grains Region of Australia. The abundance of this weed increased dramatically after the adoption of no-tillage conservation agriculture (NTCA). However, information is lacking on the germination characteristics of the two types of seed (i.e. primary and secondary) that it produces. Aims We aimed to determine the light and temperature requirements for germination and the time to germination of primary and secondary seeds of A. ludoviciana, in order to find ways to manage this weed effectively under NTCA systems. Methods Primary and secondary seeds and caryopses from two southern and two northern biotypes were exposed to a range of temperature and light regimes in the glasshouse, and germination was assessed. Key results All biotypes had ∼25% higher germination from primary than secondary seeds. Removing the hull increased caryopsis germination by ∼70%. The use of a light/dark photop...

Frontiers in Plant Science

Setaria viridis is an emerging model for cereal and bioenergy grasses because of its short stature, rapid life cycle and expanding genetic and genomic toolkits. Its close phylogenetic relationship with economically important crops such as maize and sorghum positions Setaria as an ideal model system for accelerating discovery and characterization of crop genes that control agronomically important traits. The

2020

Part of the Plant Sciences Commons, and the Soil Science Commons This document is available at https://uknowledge.uky.edu/igc/22/1/18 The 22nd International Grassland Congress (Revitalising Grasslands to Sustain Our Communities) took place in Sydney, Australia from September 15 through September 19, 2013. Proceedings Editors: David L. Michalk, Geoffrey D. Millar, Warwick B. Badgery, and Kim M. Broadfoot Publisher: New South Wales Department of Primary Industry, Kite St., Orange New South Wales, Australia

Crop Protection, 2003

High variation in results from Striga hermonthica experiments is common. The cut-root assay for in vitro screening of host and non-host plant cultivars for germination of S. hermonthica is particularly insensitive. In this study, some factors of the cut-root technique that could effect significant variation in germination percentage of a population of S. hermonthica seeds induced by the same crop cultivar were studied. It was found that excised pieces of both root and stem of maize (hybrid var 8338-1), cowpea (var IT81D-994) and soybean (var TGx 1448-2E) stimulated the germination of S. hermonthica seeds. Germination percentages obtained with maize and cowpea stem pieces were significantly higher than those produced by root pieces. Moistening filter paper on which conditioned Striga seeds were subjected to germination stimulants with 5 ml of distilled water resulted in significantly higher germination of the parasite's seeds induced by stimulants from both maize and soybean, than adding 3 ml of water, regardless of the plant part tested. Starting germination stimulant extraction immediately after cutting plant parts gave significantly higher germination percentage of S. hermonthica seeds than starting 3 h later, regardless of crop species and plant part tested. Conditioning S. hermonthica seeds and subsequent extraction of germination stimulant with non-sterile water generally resulted in higher germination percentage of S. hermonthica seeds than with sterile distilled water. These results are discussed and suggestions made about how to reduce variability of results of the cut-root method of in vitro assaying of germination stimulant production by hosts and trap crops of S. hermonthica.