Engineering homoeologs provide a fine scale for quantitative traits in polyploid.

Numerous staple crops exhibit polyploidy and are difficult to genetically modify. However, recent advances in genome sequencing and editing have enabled polyploid genome engineering. The hexaploid black nightshade species Solanum nigrum has immense potential as a beneficial food supplement. We assembled its genome at the scaffold level. After functional annotations, we identified homoeologous gene sets, with similar sequence and expression profiles, based on comparative analyses of orthologous genes with close diploid relatives Solanum americanum and S. lycopersicum. Using CRISPR-Cas9-mediated mutagenesis, we generated various mutation combinations in homoeologous genes. Multiple mutants showed quantitative phenotypic changes based on the genotype, resulting in a broad-spectrum effect on the quantitative traits of hexaploid S. nigrum. Furthermore, we successfully improved the fruit productivity of Boranong, an orphan cultivar of S. nigrum suggesting that engineering homoeologous genes could be useful for agricultural improvement of polyploid crops.

Newly Discovered Alleles of the Tomato Antiflorigen Gene SELF PRUNING Provide a Range of Plant Compactness and Yield.

In tomato cultivation, a rare natural mutation in the flowering repressor antiflorigen gene SELF-PRUNING (sp-classic) induces precocious shoot termination and is the foundation in determinate tomato breeding for open field production. Heterozygous single flower truss (sft) mutants in the florigen SFT gene in the background of sp-classic provide a heterosis-like effect by delaying shoot termination, suggesting the subtle suppression of determinacy by genetic modification of the florigen-antiflorigen balance could improve yield. Here, we isolated three new sp alleles from the tomato germplasm that show modified determinate growth compared to sp-classic, including one allele that mimics the effect of sft heterozygosity. Two deletion alleles eliminated functional transcripts and showed similar shoot termination, determinate growth, and yields as sp-classic. In contrast, amino acid substitution allele sp-5732 showed semi-determinate growth with more leaves and sympodial shoots on all shoots. This translated to greater yield compared to the other stronger alleles by up to 42%. Transcriptome profiling of axillary (sympodial) shoot meristems (SYM) from sp-classic and wild type plants revealed six mis-regulated genes related to the floral transition, which were used as biomarkers to show that the maturation of SYMs in the weaker sp-5732 genotype is delayed compared to sp-classic, consistent with delayed shoot termination and semi-determinate growth. Assessing sp allele frequencies from over 500 accessions indicated that one of the strong sp alleles (sp-2798) arose in early breeding cultivars but was not selected. The newly discovered sp alleles are potentially valuable resources to quantitatively manipulate shoot growth and yield in determinate breeding programs, with sp-5732 providing an opportunity to develop semi-determinate field varieties with higher yields.

Narrow lpa1 Metaxylems Enhance Drought Tolerance and Optimize Water Use for Grain Filling in Dwarf Rice.

Rice cultivation needs extensive amounts of water. Moreover, increased frequency of droughts and water scarcity has become a global concern for rice cultivation. Hence, optimization of water use is crucial for sustainable agriculture. Here, we characterized Loose Plant Architecture 1 (LPA1) in vasculature development, water transport, drought resistance, and grain yield. We performed genetic combination of lpa1 with semi-dwarf mutant to offer the optimum rice architecture for more efficient water use. LPA1 expressed in pre-vascular cells of leaf primordia regulates genes associated with carbohydrate metabolism and cell enlargement. Thus, it plays a role in metaxylem enlargement of the aerial organs. Narrow metaxylem of lpa1 exhibit leaves curling on sunny day and convey drought tolerance but reduce grain yield in mature plants. However, the genetic combination of lpa1 with semi-dwarf mutant (dep1-ko or d2) offer optimal water supply and drought resistance without impacting grain-filling rates. Our results show that water use, and transports can be genetically controlled by optimizing metaxylem vessel size and plant height, which may be utilized for enhancing drought tolerance and offers the potential solution to face the more frequent harsh climate condition in the future.

Binding, Antioxidant and Anti-proliferative Properties of Bioactive Compounds of Sweet Paprika (Capsicum annuum L.).

The scope of this research was to determine the bioactive composition, antioxidant, binding, and anti-proliferative properties of red sweet paprika growing under artificial light. The amounts of carotenoids, chlorophyll, polyphenols, tannins, and flavonoids in red paprika (RP), cultivated in Korea, before and after light treatments under high pressure sodium (HPS) and lighting emitting plasma (LEP) lamps (RPControl, RPHPS, RPLEP), were analyzed in water (W) and ethanolic extracts (Et). Spectroscopic, radical scavenging assays, fluorescence and cytotoxicity measurements were applied. The results of this study showed that total chlorophyll and carotenes were the highest in RPHPS (10.50 ± 1.02 and 33.90 ± 3.26 µg/g dry weight (DW)). The strongest antioxidant capacity (µM TE/g DW) in a 2, 2'-azino-bis (3-ethyl-benzothiazoline-6-sulfonic acid) diammonium salt (ABTS(•+)) assay was in RPControlEt (24.34 ± 2.36), in a ferric-reducing/antioxidant power (FRAP) assay in RPHPSW (27.08 ± 2.4) and in a cupric reducing antioxidant (CUPRAC) in RPLEPW (70.99 ± 7.11). The paprika ethanolic extracts showed lower values in their bioactivity than the water ones. The binding and cytotoxicity abilities of extracted polyphenols correlated with their amounts. LEP treatment is better for plant growth characteristics than other conventional treatments. The investigated paprika samples can be used as a source of antioxidants.

Phytoremediation of Heavy Metals in Contaminated Water and Soil Using Miscanthus sp. Goedae-Uksae 1.

The aim of this study is to characterize the heavy metal phytoremediation potential of Miscanthus sp. Goedae-Uksae 1, a hybrid, perennial, bio-energy crop developed in South Korea. Six different metals (As, Cu, Pb, Ni, Cd, and Zn) were used for the study. The hybrid grass effectively absorbed all the metals from contaminated soil. The maximum removal was observed for As (97.7%), and minimum removal was observed for Zn (42.9%). Similarly, Goedae-Uksae 1 absorbed all the metals from contaminated water except As. Cd, Pb, and Zn were completely (100%) removed from contaminated water samples. Generally, the concentration of metals in roots was several folds higher than in shoots. Initial concentration of metals highly influenced the phytoremediation rate. The results of the bioconcentration factor, translocation factor, and enrichment coefficient tests indicate that Goedae-Uksae 1 could be used for phytoremediation in a marginally contaminated ecosystem.

Bioactive compounds, antioxidant and binding activities and spear yield of Asparagus officinalis L.

The aim of this investigation was to find a proper harvesting period and establishing fern number, which effects the spear yield, bioactive compounds and antioxidant activities of Asparagus officinalis L. Spears were harvested at 2, 4, and 6 weeks after sprouting. Control for comparison was used without harvest. Spears and total yield increased with prolonged spear harvest period. In harvest of 6 weeks long optimum spear yield was the highest and fern numbers were 5 ~ 8. Bioactive compounds (polyphenols, flavonoids, flavanols, tannins and ascorbic acid) and the levels of antioxidant activities by ferric-reducing/antioxidant power (FRAP) and cupric reducing antioxidant capacity (CUPRAC) assays in asparagus ethanol extracts significantly differed in the investigated samples and were the highest at 6 weeks harvest period (P < 0.05). The first and the second segments from the tip significantly increased with the increase of catalase (CAT). It was interesting to investigate in vitro how human serum albumin (HSA) interacts with polyphenols extracted from investigated vegetables. Therefore the functional properties of asparagus were studied by the interaction of polyphenol ethanol extracts with HSA, using 3D- FL. In conclusion, antioxidant status (bioactive compounds, binding and antioxidant activities) improved with the harvesting period and the first segment from spear tip. Appropriate harvesting is effective for higher asparagus yield and its bioactivity.

Antiproliferative activity of Korean wild vegetables on different human tumor cell lines.

This study was conducted to determine the antiproliferative activity of 24 Korean wild vegetables. The methanol extracts of these wild vegetables were used against lung, breast, colon and gastric cancer cells, and the results were assessed by MTT assay. It was found that at the extract concentration of 400 mgL(-1) 14 plants exercised antiproliferative activity over 80% against the lung cancer cells, one plant among six--against breast cancer cells, and two plants among six--against colon cancer cells, respectively. Eighteen wild vegetables had the hyperplasia inhibition activity against gastric cancer cells over 23.6% at all extract concentrations, however, only six plants had the antiproliferative activity over 80% in 600 mgL(-1). It was found that the extracts from Youngia sonchifolia, Synurus deltoides, Syneilesis palmata, and Cephalonoplos segetum, in concentration of 400 mgL(-1) inhibited the hyperplasia of lung cancer cells over 95% and Angelica gigas-both lung and colon cancer cells over 95%. In conclusion, the studied wild vegetables' methanol extracts possess dose dependent antiproliferative properties, based on their bioactive compounds, mainly polyphenols, but some of them as Hypericum ascyron against lung cancer are not effective and even course harm.