title: Optimum harvest maturity for Leymus chinensis seed.
abstract: Timely harvest is critical to achieve maximum seed viability and vigour in agricultural production. However, little information exists concerning how to reap the best quality seeds of Leymus chinensis, which is the dominant and most promising grass species in the Songnen Grassland of Northern China. The objective of this study was to investigate and evaluate possible quality indices of the seeds at different days after peak anthesis. Seed quality at different development stages was assessed by the colours of the seed and lemmas, seed weight, moisture content, electrical conductivity of seed leachate and germination indices. Two consecutive years of experimental results showed that the maximum seed quality was recorded at 39 days after peak anthesis. At this date, the colours of the seed and lemmas reached heavy brown and yellow, respectively. The seed weight was highest and the moisture content and the electrical conductivity of seed leachate were lowest. In addition, the seed also reached its maximum germination percentage and energy at this stage, determined using a standard germination test (SGT) and accelerated ageing test (AAT). Thus, Leymus chinensis can be harvested at 39 days after peak anthesis based on the changes in parameters. Colour identification can be used as an additional indicator to provide a more rapid and reliable measure of optimum seed maturity; approximately 10 days after the colour of the lemmas reached yellow and the colour of the seed reached heavy brown, the seed of this species was suitable for harvest.
authors.affiliation: Alkali Soil Natural Environmental Science Center, Northeast Forestry University/Key Laboratory of Saline-Alkali Vegetation Ecology Restoration in Oil Field, Ministry of Education, Harbin 150040, China Key Laboratory of Vegetation Ecology of Ministry of Education, Institute of Grassland Science, Northeast Normal University, Changchun 130024, China.
authors.forename: Jixiang
authors.initials: J
authors.lastname: Lin
authors.affiliation: Alkali Soil Natural Environmental Science Center, Northeast Forestry University/Key Laboratory of Saline-Alkali Vegetation Ecology Restoration in Oil Field, Ministry of Education, Harbin 150040, China.
authors.forename: Yingnan
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Alkali Soil Natural Environmental Science Center, Northeast Forestry University/Key Laboratory of Saline-Alkali Vegetation Ecology Restoration in Oil Field, Ministry of Education, Harbin 150040, China.
authors.forename: Mingming
authors.initials: M
authors.lastname: Qi
authors.affiliation: Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130012, China.
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Li
authors.affiliation: Alkali Soil Natural Environmental Science Center, Northeast Forestry University/Key Laboratory of Saline-Alkali Vegetation Ecology Restoration in Oil Field, Ministry of Education, Harbin 150040, China.
authors.forename: Chunxue
authors.initials: C
authors.lastname: Yang
authors.affiliation: Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
authors.forename: Yongcui
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Key Laboratory of Vegetation Ecology of Ministry of Education, Institute of Grassland Science, Northeast Normal University, Changchun 130024, China mucs821@gmail.com.
authors.forename: Chunsheng
authors.identifier: http://orcid.org/0000-0002-3577-7405
authors.initials: C
authors.lastname: Mu
keywords: Leymus chinensis; Seed colour; Seed quality; Timely harvest; Weight