Wild rice (Zizania spp.), an aquatic grass belonging to the subfamily Gramineae, has a high economic value. Zizania provides food (such as grains and vegetables), a habitat for wild animals, and paper-making pulps, possesses certain medicinal values, and helps control water eutrophication. Zizania is an ideal resource for expanding and enriching a rice breeding gene bank to naturally preserve valuable characteristics lost during domestication. With the Z. latifolia and Z. palustris genomes completely sequenced, fundamental achievements have been made toward understanding the origin and domestication, as well as the genetic basis of important agronomic traits of this genus, substantially accelerating the domestication of this wild plant. The present review summarizes the research results on the edible history, economic value, domestication, breeding, omics research, and important genes of Z. latifolia and Z. palustris over the past decades. These findings broaden the collective understanding of Zizania domestication and breeding, furthering human domestication, improvement, and long-term sustainability of wild plant cultivation.

BackgroundThe implementation of the Millennium Forestry Plan was accompanied by growth discomfort exhibiting varying degrees of symptoms in some coniferous forests after the rainy season.HypothesisHigh soil water content affects the underground root growth and distribution characteristics of conifers, and the above-ground parts show corresponding variability. To determine the factors contributing to the significant growth disparities among the three conifers in Xiong’an New Area after the rainy season, we conducted a study investigating the growth characteristics of conifers. This study involved analyzing the external morphology of the plants, assessing leaf pigment content, measuring the root morphological index and root vigor, as well as respiratory characteristics, to evaluate the growth attributes of their root systems in a high soil moisture environment.MethodsIn the “Millennium Forest” area of Xiong’an New Area, we selected three coniferous trees, Pinus tabuliformis, Pinus bungeana and Pinus armandii, and set up three standard sample plots for each conifer. The conifers were classified into 3 levels according to their growth performance (vigorous or suppressed), leaf condition (color change, wilting or not) and relevant grading criteria.Results(1) The growth of the three conifers displayed discernible differences in external morphology. Moreover, a decrease in growth condition corresponded to a reduction in crown size, ground diameter, diameter at breast height, leaf length, and new growths. (2) The root biomass, length, surface area, and root volume of conifers growing N class were significantly reduced than those of L class conifers. Conifers with a higher proportion of root systems in the 40-60 cm soil layer experienced more severe stress. (3) The significant decline in root respiration and vigor among all three conifer growth classes (M and N) suggested that the root system was undergoing anoxic stress, particularly at a soil depth of 40-60 cm where root respiration and vigor were notably reduced. (4) The persistent anoxic stress created by long-term exposure to high soil moisture content primarily impacted P. armandii to a greater extent than P. tabuliformis and P. bungeana. Additionally, the transporting and absorbing root ratios varied among conifers with differing growth conditions. The long-term high moisture environment also caused partial death of absorbing roots, which played a key role in the observed differences in growth. (5) As the soil depth increases, the soil water content increases accordingly. Plants with more root distribution in the deeper soil layers grow worse than those distributed in the top soil layers. Soil water content is related to aeration, root distribution, growth and growth of above-ground parts. The variability of root distribution and growth led to the differentiation of the growth of the above-ground part of the plant in terms of external morphology, which inhibited the overall plant growth. The results of the study provide a theoretical basis for the cultivation and management of three conifers in high soil moisture environments.

DnaJs are the common molecular chaperone proteins with strong structural and functional diversity. In recent years, only several DnaJ family members have been found to be able to regulate leaf color, and it remains to be explored whether there are other potential members that also regulate this character. Here, we identified 88 putative DnaJ proteins from Catalpa bungei, and classified them into four types according to their domain. Gene-structure analysis revealed that each member of CbuDnaJ family had same or similar exon-intron structure. Chromosome mapping and collinearity analysis showed that tandem and fragment duplication occurred in the process of evolution. Promoter analyses suggested that CbuDnaJs might be involved in a variety of biological processes. The expression levels of DnaJ family members in different color leaves of Maiyuanjinqiu were respectively extracted from the differential transcriptome. Among these, CbuDnaJ49 was the largest differentially expressed gene between the green and yellow sectors. Ectopic overexpression of CbuDnaJ49 in tobacco showed that the positive transgenic seedlings exhibited albino leaves, and the contents of chlorophyll and carotenoid were significantly reduced compared with those of wild type. The results suggested that CbuDnaJ49 played an important role in regulating leaf color. This study not only identified a novel gene of DnaJ family members regulating leaf color, but also provided new germplasm for landscaping.

Fencing is the most economical method of restoring degraded desert ecosystems, and plays an important role in promoting plant community diversity and productivity, as well as stable ecosystem structure and function. In this study, we selected a typical degraded desert plant community (Reaumuria songorica–Nitraria tangutorum) on the edge of a desert oasis in the Hexi Corridor in northwest China. We then investigated succession in this plant community and corresponding changes in soil physical and chemical characteristics over 10 years of fencing restoration to analyze the mutual feedback mechanisms. The results showed that: 1) The diversity of plant species in the community increased significantly over the study period, especially the number of herbaceous layer species, which increased from four in the early stage to seven in the late stage. The dominant species also changed, with the dominant shrub layer species shifting from N. sphaerocarpa in the early stage to R. songarica in the late stage. The dominant herbaceous layer species changed from the annual herb Suaeda glauca in the early stage to S. glauca and Artemisia scoparia in the middle stage, and ultimately to A. scoparia and Halogeton arachnoideus in the late stage. In the late stage, Zygophyllum mucronatum, H. arachnoideus, and Eragrostis minor began to invade, and the density of perennial herbs also increased significantly (from 0.01 m-2 to 0.17 m-2 for Z. kansuense in year seven). 2) As the duration of fencing increased, the soil organic matter (SOM) and total nitrogen (TN) contents first decreased then increased, whereas the available nitrogen, potassium, and phosphorus contents showed the opposite trend. 3) Changes in community diversity were mainly affected by the nursing effects of the shrub layer, as well as soil physical and chemical properties. That is, fencing significantly increased the vegetation density of the shrub layer, which promoted growth and development of the herbaceous layer. However, community species diversity was positively correlated with SOM and TN. The diversity of the shrub layer was positively correlated with the water content of deep soil, whereas that of the herbaceous layer was positively correlated with SOM, TN, and soil pH. The SOM content in the later stage of fencing was 1.1 times that in the early stage of fencing. Thus, fencing restored the density of the dominant shrub species and significantly increased species diversity, especially in the herb layer. Studying plant community succession and soil environmental factors under long-term fencing restoration is highly significant for understanding community vegetation restoration and ecological environment reconstruction at the edge of desert oases.

DnaJs are the common molecular chaperone proteins with strong structural and functional diversity. In recent years, only several DnaJ family members have been found to be able to regulate leaf color, and it remains to be explored whether there are other potential members that also regulate this character. Here, we identified 88 putative DnaJ proteins from Catalpa bungei, and classified them into four types according to their domain. Gene-structure analysis revealed that each member of CbuDnaJ family had same or similar exon-intron structure. Chromosome mapping and collinearity analysis showed that tandem and fragment duplication occurred in the process of evolution. Promoter analyses suggested that CbuDnaJs might be involved in a variety of biological processes. The expression levels of DnaJ family members in different color leaves of Maiyuanjinqiu were respectively extracted from the differential transcriptome. Among these, CbuDnaJ49 was the largest differentially expressed gene between the green and yellow sectors. Ectopic overexpression of CbuDnaJ49 in tobacco showed that the positive transgenic seedlings exhibited albino leaves, and the contents of chlorophyll and carotenoid were significantly reduced compared with those of wild type. The results suggested that CbuDnaJ49 played an important role in regulating leaf color. This study not only identified a novel gene of DnaJ family members regulating leaf color, but also provided new germplasm for landscaping.

N6-methyladenosine (m6A) is the most abundant internal modification in eukaryotic messenger RNA, and involved in various biological processes in plants. However, the distribution features and functions of mRNA m6A methylation have been poorly explored in woody perennial plants. In this study, a new natural variety with yellow-green leaves, named Maiyuanjinqiu, was screened from the seedlings of Catalpa fargesii. Based on the preliminary experiment, the m6A methylation levels in the leaves of Maiyuanjinqiu were significantly higher than those in C. fargesii. Furthermore, a parallel analysis of m6A-seq and RNA-seq was carried out in different leaf color sectors. The result showed that m6A modification were mostly identified around the 3’-untranslated regions (3’-UTR), which was slightly negatively correlated with the mRNA abundance. KEGG and GO analyses showed that m6A methylation genes were associated with photosynthesis, pigments biosynthesis and metabolism, oxidation-reduction and response to stress, etc. The overall increase of m6A methylation levels in yellow-green leaves might be associated with the decreased the expression of RNA demethylase gene CfALKBH5. The silencing of CfALKBH5 caused a chlorotic phenotype and increased m6A methylation level, which further confirmed our hypothesis. Our results suggested that mRNA m6A methylation could be considered as a vital epigenomic mark and contribute to the natural variations in plants.