Salt stress causes significant reductions in rice production worldwide; thus, improving salt tolerance is a promising approach to meet the increasing food demand. Wild rice germplasm is considered a valuable genetic resource for improving rice cultivars. However, information regarding the improvement of salt tolerance in cultivated rice using wild rice genes is limited. In this study, we identified a salt-tolerant line Dongxiang/Ningjing 15 (DJ15) under salt-stress field conditions from the population of a salt tolerant Dongxiang wild rice × a cultivated rice variety Ningjing16 (NJ16). Genomic resequencing analysis of NJ16, DJ15 and Dongxiang wild rice revealed that the introgressed genomic fragments were unevenly distributed over the 12 chromosomes (Chr.) and mainly identified on Chr. 6, 7, 10, and 11. Using quantitative trait locus (QTL) mapping, we found 9 QTL for salt tolerance (qST) at the seedling stage located on Chr. 1, 3, 4, 5, 6, 8, and 10. In addition, sequence variant analysis within the QTL regions demonstrated that SKC1/HKT8/HKT1;5 and HAK6 transporters along with numerous transcriptional factors were the candidate genes for the salt tolerant QTL. The DJ15/Koshihikari recombinant inbred lines that contained both qST1.2 and qST6, two QTL with the highest effect for salt tolerance, were more tolerant than the parental lines under salt-stress field conditions. Furthermore, the qST6 near-isogenic lines with IR29 background were more tolerant than IR29, indicating that qST1.2 and qST6 could improve salt tolerance in rice. Overall, our study indicates that wild rice genes could markedly improve the salt tolerance of cultivated rice.

A total of 75 male mice were allotted to five groups of 15 each in a completely randomized experimental design to study the effects of probiotics, inorganic selenium, and selenium-enriched probiotics on male fertility in hyperlipidemic status. The mice in group 1 were fed a normal basal diet and served as negative control. The mice in group 2 were fed a high fat diet and served as positive control. The mice in groups 3, 4, and 5 were fed the high fat diet supplemented with probiotics, inorganic selenium, and selenium-enriched probiotics, respectively. The high fat diet was composed of 15% lard, 1% cholesterol, 0.3% cholic acid, and 83.7% basal diet. Over 90% of the selenium in the selenium-enriched probiotics was present in forms of organic selenium. After the mice were fed these diets for 75 days, serumal total cholesterol, triglycerides, low density lipoprotein, high density lipoprotein, and testosterone levels, plus sperm index (count, motility and abnormalities), penis length, and weight and histopathology of testes were measured. The results showed that in the mice fed the high fat diet were significant (P < 0.01) elevations of serumal total cholesterol, triglycerides and low density lipoprotein, and decreases of high density lipoprotein. The high fat diet caused a decline in serumal testosterone level, reduced semen quality, and atrophy and degeneration of seminiferous tubules. No effects on penis length or relative weight of testis were observed. Supplementation of probiotics, inorganic selenium, or selenium-enriched probiotics to the high fat diet significantly alleviated (P < 0.05) the adverse effects of hyperlipidemia by reducing testicular tissue injury, increasing serumal testosterone level, and improving sperm indexes. It was concluded that hyperlipidemia had significant adverse effects on male fertility, which could be ameliorated at various degrees by feeding the diets supplemented with probiotics, inorganic selenium, or selenium-enriched probiotics. Selenium-enriched probiotics or inorganic selenium supplementation gave better results than probiotics supplementation and may be used to improve animal and human male fertility compromised by hyperlipidemia or obesity.

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Tocochromanol, or vitamin E, plays a crucial role in human and animal nutrition and is synthesized only by photosynthetic organisms. γ-Tocopherol methyltransferase (γ-TMT), one of the key enzymes in the tocopherol biosynthetic pathway in plants, converts γ, δ-tocopherols into α-, β-tocopherols. Tocopherol content was investigated in 15 soybean cultivars and GmTMT2 was isolated from five varieties based on tocopherol content. GmTMT2a was expressed in E. coli and the purified protein effectively converted γ-tocopherol into α-tocopherol in vitro. Overexpression of GmTMT2a enhanced α-tocopherol content 4-6-fold in transgenic Arabidopsis, and α-tocopherol content increased 3-4.5-fold in transgenic maize seed, which correlated with the accumulation of GmTMT2a. Transgenic corn that is α-tocopherol-rich may be beneficial for animal health and growth.

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