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Lodging results in severe yield loss and harvest difficulty in wheat production, especially in the drip-irrigation technique dominated wheat system in arid area of North-west China. We assume that our previously developed enlarging lateral space (ELS) drip irrigation pattern benefits plant lodging resistance due to the enlarged border row space (BRS) by narrowing row space (NRS). In a three-year field experiment, we compared spring wheat lodging resistance of the ELS patterns with the conventional drip irrigation pattern of TR4 (one drip tube serves plant rows (TR) of four, with normal row space (RS) of 15 cm, as control). Six ELS patterns included the normal ELS patterns of TR6 and TR8 (expanding TR from four to six and eight, with normal RS of 15 cm), large BRS ELS patterns of TR6L (BRS of 35 cm) and TR8L (BRS of 45 cm) by narrowing RS to 10 cm, and shorter BRS ELS patterns of TR6S and TR8S with BRS of 25 cm and RS of 10 cm. The normal ELS patterns with even RS (TR6 & TR8) (10.82–48.21%) significantly increased lodging rate as compared with TR4 (7.22–42.41%). Reversely, patterns with broadened BRS effectively reduced lodging rate (5.62–39.55% for TR6L & TR8L, 6.18–41.73% for TR6S & TR8S). The much improved lodging resistance of the outermost or the border rows essentially contributed to the much lower lodging rate of the modified ELS patterns. The border plants in the modified ELS patterns performed higher photosynthesis of leaf and lignin content in basal stems, subsequently increased stem pole substantial degree and finally improved stem mechanical properties. In addition, the modified ELS patterns also optimized accumulation and redistribution of dry matter in stems in the outermost rows. Therefore, the modified ELS drip irrigation patterns via NRS which leaved border effects were recommended as low lodging risks approach towards stabilized wheat productivity, of which TR6S was strongly recommended.

Here we document physiological and molecular attributes of three wheat cultivars (ZM9023, YM158 and FM1228) under low light intensity with advanced technologies, including non-standard quantitative technology and quantitative proteomics technology. We found lower dry matter accumulation of YM158 compared with ZM 9023 and FM1228 under low light intensities due to up-regulation of photosynthetic parameters electron transport rate (ETR), Y(II), Fv/Fm, Chl (a + b) of YM158 and down-regulation of Chl a/b. ETR, Y(II) and Fv/Fm significantly decreased between ZM9023 and FM1228. The ETR between PSII and PSI of YM158 increased, while light use efficiency (LUE) of ZM9023 and FM1228 decreased. We found that YM158 had greater propensity to adapt to low light compared with ZM9023, as the former was able to increase photochemical electron transfer rate, enhance photosystem activity, and increase the light energy under low light. This meant that the YM158 flag leaf has stronger regulatory mechanism under low light environment. Through proteomic analysis, we found LHC protein (LHCB1, LHCB4, LHCA2, LHCA3) for YH158 was significantly up-regulated, while the PSII subunit protein of FM1228 and ZM9023 b559 subunit protein were down-regulated. We also documented enhanced light use efficiency (LUE) due to higher light capture pigment protein complex (LHC), photosystem II (PSII), PSI and cytochrome B6F-related proteins, with dry matter accumulation being positively correlated with Fv/Fm, ETR, and ΦPS(II), and negatively correlated with initial fluorescence F0. We suggest that Fv/Fm, ETR, and ΦPS(II) could be considered in shade tolerance screening to facilitate wheat breeding.

Wheat (Triticum aestivum L.), the most widely cultivated crop, is affected by waterlogging that limited the wheat production. Given the incompleteness of its genome annotation, PacBio SMRT plus Illumina short-read sequencing strategy provided an efficient approach to investigate the genetic regulation of waterlogging stress in wheat. A total of 947,505 full-length non-chimetric (FLNC) sequences were obtained with two wheat cultivars (XM55 and YM158) with PacBio sequencing. Of these, 5,309 long-non-coding RNAs, 1,574 fusion genes and 739 transcription factors were identified with the FLNC sequences. These full-length transcripts were derived from 49,368 genes, including 47.28% of the genes annotated in IWGSC RefSeq v1.0 and 40.86% genes encoded two or more isoforms, while 27.31% genes in the genome annotation of IWGSC RefSeq v1.0 were multiple-exon genes encoding two or more isoforms. Meanwhile, the individuals with waterlogging treatments (WL) and control group (CK) were selected for Illumina sequencing. Totally, 6,829 differentially expressed genes (DEGs) were detected from four pairwise comparisons. Notably, 942 DEGs were overlapped in the two comparisons (i.e., XM55-WL vs. YM158-WL and YM158-WL vs. YM158-CK). Undoubtedly, the genes involved in photosynthesis were downregulated after waterlogging treatment in two cultivars. Notably, the genes related to steroid biosynthesis, steroid hormone biosynthesis, and downstream plant hormone signal transduction were significantly upregulated after the waterlogging treatment, and the YM158 variety revealed different genetic regulation patterns compared with XM55. The findings provided valuable insights into unveiling regulation mechanisms of waterlogging stress in wheat at anthesis and contributed to molecular selective breeding of new wheat cultivars in future.