It is concluded from a review of the literature that plant cell culture itself generates genetic variability (somaclonal variation). Extensive examples are discussed of such variation in culture subclones and in regenerated plants (somaclones). A number of possible mechanisms for the origin of this phenomenon are considered. It is argued that this variation already is proving to be of significance for plant improvement. In particular the phenomenon may be employed to enhance the exchange required in sexual hybrids for the introgression of desirable alien genes into a crop species. It may also be used to generate variants of a commercial cultivar in high frequency without hybridizing to other genotypes.

Somaclonal variation — a novel source of variability from cell cultures for plant improvement

When exposed to stressful conditions, plants accumulate an array of metabolites, particularly amino acids. Amino acids have traditionally been considered as precursors to and constituents of proteins, and play an important role in plant metabolism and development. A large body of data suggests a positive correlation between proline accumulation and plant stress. Proline, an amino acid, plays a highly beneficial role in plants exposed to various stress conditions. Besides acting as an excellent osmolyte, proline plays three major roles during stress, i.e., as a metal chelator, an antioxidative defense molecule and a signaling molecule. Review of the literature indicates that a stressful environment results in an overproduction of proline in plants which in turn imparts stress tolerance by maintaining cell turgor or osmotic balance; stabilizing membranes thereby preventing electrolyte leakage; and bringing concentrations of reactive oxygen species (ROS) within normal ranges, thus preventing oxidative burst ...

https://www.tandfonline.com/doi/pdf/10.4161/psb.21949

Role of proline under changing environments: a review.

According to the invention, there is provided an inbred corn plant designated 89AHD12. This invention thus relates to the plants, seeds and tissue cultures of the inbred corn plant 89AHD12, and to methods for producing a corn plant produced by crossing the inbred corn plant 89AHD12 with itself or with another corn plant, such as another inbred. This invention further relates to corn seeds and plants produced by crossing the inbred plant 89AHD12 with another corn plant, such as another inbred, and to crosses with related species. This invention further relates to the inbred and hybrid genetic complements of the inbred corn plant 89AHD12, and also to the SSR and genetic isozyme typing profiles of inbred corn plant 89AHD12.

Inbred corn plant 89AHD12 and seeds thereof

An inbred corn line, designated LH283BtMON810, is disclosed. The invention relates to the seeds of inbred corn line LH283BtMON810, to the plants of inbred corn line LH283BtMON810 and to methods for producing a corn plant, either inbred or hybrid, by crossing the inbred line LH283BtMON810 with itself or another corn line. The invention further relates to methods for producing a corn plant containing in its genetic material one or more transgenes and to the transgenic plants produced by that method and to methods for producing other inbred corn lines derived from the inbred LH283BtMON810.

Inbred corn line LH283BtMON810

Transformants of maize inbred A188 were efficiently produced from immature embryos cocultivated with Agrobacterium tumefaciens that carried "super-binary" vectors. Frequencies of transformation (independent transgenic plants/embryos) were between 5% and 30%. Almost all transformants were normal in morphology, and more than 70% were fertile. Stable integration, expression, and inheritance of the transgenes were confirmed by molecular and genetic analysis. Between one and three copies of the transgenes were integrated with little rearrangement, and the boundaries of T-DNA were similar to those in transgenic dicotyledons and rice. F1 hybrids between A188 and five other inbreds were transformed at low frequencies.

High efficiency transformation of maize (Zea mays L.) mediated by Agrobacterium tumefaciens

Health risk caused by Cd containing food is concerned worldwide. Interaction between Mn and Cd has been widely studied in normal hydroponic solution with high ion activities, e.g., the study on sharing of transporter Natural Resistance-Associated Macrophage Protein 5 (OsNRAMP5) between Mn and Cd in rice. However, interaction of Mn and Cd in crops like rice and spinach at field ion activity level is still unknown. Thus, ethyleneglycoltetraacetate (EGTA)-buffered solution experiment was conducted in this work to explore the effect of Mn on the uptake and accumulation of Cd and other mineral elements in rice and spinach. In rice, antagonism of Mn and Cd was only observed in roots at deficient and toxic levels of external Mn2+ activities. Compared with those at Mn2+ sufficiency (pMn2+ 6.7-5.3), average root Cd elevated significantly by 1.85-3.05 times at Mn2+ deficiency (pMn2+ 8.2), while decreased by 1.57-2.59 times at Mn2+ toxicity (pMn2+ 4.8). The antagonism between Mn and K/Mg in rice shoots might be caused by their common role in physiological processes in plants. Antagonism of Mn/Ni in spinach in this work was consistent with their shared transporters in dicots as reported. Results about the antagonism of root Cd/Mn at Mn2+ deficiency suggested that sufficiently available Mn2+ is significant to reduce Cd uptake in rice under field level of ion activity, while it was not for spinach since the change of tissue Cd was insignificant with the increase of Mn2+ activity from deficiency to toxicity. This article is protected by copyright. All rights reserved.

C. E. Green

Papers

Effects of Mn2+ on Cd Accumulation and Ionome in Rice and Spinach.