Mapping and Screening of Candidate Gene Regulating the Biomass Yield of Sorghum (Sorghum bicolor L.).

Biomass yield is one of the important traits of sorghum, which is greatly affected by leaf morphology. In this study, a lobed-leaf mutant (sblob) was screened and identified, and its F2 inbred segregating line was constructed. Subsequently, MutMap and whole-genome sequencing were employed to identify the candidate gene (sblob1), the locus of which is Sobic.003G010300. Pfam and homologous analysis indicated that sblob1 encodes a Cytochrome P450 protein and plays a crucial role in the plant serotonin/melatonin biosynthesis pathway. Structural and functional changes in the sblob1 protein were elucidated. Hormone measurements revealed that sblob1 regulates both leaf morphology and sorghum biomass through regulation of the melatonin metabolic pathway. These findings provide valuable insights for further research and the enhancement of breeding programs, emphasizing the potential to optimize biomass yield in sorghum cultivation.

Expression of Foreign Genes Demonstrates the Effectiveness of Pollen-Mediated Transformation in Zea mays.

Plant genetic transformation has arguably been the core of plant improvement in recent decades. Efforts have been made to develop in planta transformation systems due to the limitations present in the tissue-culture-based methods. Herein, we report an improved in planta transformation system, and provide the evidence of reporter gene expression in pollen tube, embryos and stable transgenicity of the plants following pollen-mediated plant transformation with optimized sonication treatment of pollen. The results showed that the aeration at 4°C treatment of pollen grains in sucrose prior to sonication significantly improved the pollen viability leading to improved kernel set and transformation efficiency. Scanning electron microscopy observation revealed that the removal of operculum covering pollen pore by ultrasonication might be one of the reasons for the pollen grains to become competent for transformation. Evidences have shown that the eGfp gene was expressed in the pollen tube and embryos, and the Cry1Ac gene was detected in the subsequent T1 and T2 progenies, suggesting the successful transfer of the foreign genes to the recipient plants. The Southern blot analysis of Cry1Ac gene in T2 progenies and PCR-identified Apr gene segregation in T2 seedlings confirmed the stable inheritance of the transgene. The outcome illustrated that the pollen-mediated genetic transformation system can be widely applied in the plant improvement programs with apparent advantages over tissue-culture-based transformation methods.

Effects of dietary transgenic poplar leaf pellets on performance and tissues in rabbits.

BACKGROUND: Various studies have been conducted to evaluate the effect of Bt crops on animals. Insect-resistant bioassays have revealed that the chitinase-BmkIT combination could be used as a new pest-resistant gene source and might be a complementary alien gene source to the Bt toxin gene. So it is necessary to assay the effects of chitinase-BmkIT plants on animals. RESULTS: Forty 40-day old New Zealand White Rabbits (Oryctolagus cuniculus) were fed for 60 consecutive days with formulated feed containing dehydrated poplar (Populus cathayana Rehd) leaves harbouring chitinase-BmkIT gene combination or untransformed counterparts, and the potential toxicological effects of transgenic leaves on rabbits were explored. The results of the growth study revealed no significant differences for daily weight gain, feed intake and feed conversion ratio where they were 101.6%, 99.2% and 97.8% of the treatment compared to the control, respectively. No obvious pathological change was observed in the small intestine, stomach, spleen, kidney, lung, heart, bladder, pancreas, prostate and ovary. Electron microscopy observations of liver cells and renal cells showed they were both normal in the two groups. No feed-derived chitinase, BmkIT and NPTII genes were found in small intestine, blood, or leg muscle samples although they were detected in the formulated feed. CONCLUSION: We conclude that the processed poplar leaves with foreign chitinase-BmkIT genes had no obviously harmful effects on rabbits.