Understanding the Plant Aphid Interaction: A Review

The interaction between plant-aphid is phenomenal and complex. Aphids possess efficient mouthparts which feed on plant sap intensively. Adaptation to host plants and successful feeding is achieved through the strategic ability of aphids to reproduce sexually and asexually (parthenogenesis). Aphid infestation damages the plant in diverse ways and induces plant defense. Though plant elicit direct and indirect defense to resist aphid feeding, the effectiveness of plant resistance depends largely on the aphid infestation rate and quality of the host plant. To control aphid infestation and plant damage, dependency on insecticides is undesirable due to insecticidal resistance of aphids and environmental pollution. The approach towards the development of the genetically engineered crops which are aphid resistant can be the considerable potential to aphid control..

Erroneous Belief that Digestive Stability Predicts Allergenicity May Lead to Greater Risk for Novel Food Proteins

There continues to be an erroneous belief that allergens (especially food allergens) are more resistant to gastrointestinal digestion than non-allergens. Government regulations based on this erroneous belief may result in technology developers altering the amino acid sequences of digestively stable native proteins to create digestively unstable modified versions for expression in genetically engineered crops. However, an investigation where a known stable allergen was modified to make it more digestible eliminated the protein’s ability to tolerize against allergy in a mouse model, which is consistent with the dual allergen exposure hypothesis. Thus, the false belief that digestive stability increases the allergenic risk of novel food proteins (e.g., such as expressed in genetically engineered crops) could, in some cases, lead to introduction of digestively unstable modified protein versions with greater sensitization risk. However, it is noteworthy that developers have historically been very effective at preventing allergens from being introduced into crops based on the other components of the weight-of-evidence assessment of allergenic risk such that no newly expressed protein in any commercialized genetically engineered crop has ever been documented to cause allergy in anyone.

ROLE OF CRISPR TO IMPROVE ABIOTIC STRESS TOLERANCE IN CROP PLANTS

The study for genetic variation in plant genomes for a variety of crops, as well as developments of genome editing techniques, have made it possible to cultivate for about any desired trait. Zinc finger enzymes; have made strides in genome-editing. Molecular biologists can now more specifically target every gene using transcription activator-like effector nucleases and ZFNs. These methods, on the other hand, are expensive and time-consuming because they involve complex procedures. Referring to various genome editing techniques, CRISPR/Cas9 genetic modification is simple to construct and clone and the Cas9 could be used with different guide RNAs controlling different genes. Following solid evidence demonstrations using the main CRISPR-Cas9 unit in field crops, multiple updated Cas9 cassettes are often used in plant species to improve target precision and reduce off target cleavage. Nmcas9, Sacas9, as well as Stcas9 are a few examples. Furthermore, Cas9 enzymes are readily available from a variety of sources. Bacteria that had never been discovered before has found solutions available to improve specificity and efficacy of gene editing techniques. The choices are summarized in this analysis to plant's experiment to develop crops using CRISPR/Cas9 technology; the tolerance of biotic & abiotic stress may be improved. These strategies will lead to the growth of non-genetically engineered crops with the target phenotype, which will further improve yield capacity under biotic & abiotic stress environments.

History of safe exposure and bioinformatic assessment of phosphomannose-isomerase (PMI) for allergenic risk

Newly expressed proteins in genetically engineered crops are evaluated for potential cross reactivity to known allergens as part of their safety assessment. This assessment uses a weight-of-evidence approach. Two key components of this allergenicity assessment include any history of safe human exposure to the protein and/or the source organism from which it was originally derived, and bioinformatic analysis identifying amino acid sequence relatedness to known allergens. Phosphomannose-isomerase (PMI) has been expressed in commercialized genetically engineered (GE) crops as a selectable marker since 2010 with no known reports of allergy, which supports a history of safe exposure, and GE events expressing the PMI protein have been approved globally based on expert safety analysis. Bioinformatic analyses identified an eight-amino-acid contiguous match between PMI and a frog parvalbumin allergen (CAC83047.1). While short amino acid matches have been shown to be a poor predictor of allergen cross reactivity, most regulatory bodies require such matches be assessed in support of the allergenicity risk assessment. Here, this match is shown to be of negligible risk of conferring cross reactivity with known allergens.

The climate benefits of yield increases in genetically engineered crops

The benefits of genetically engineered (GE) crops are systematically underestimated because previous studies did not incorporate the reduction in greenhouse gas (GHG) emissions associated with yield increases. We estimate this impact using the carbon opportunity cost of land use. Our results suggest that the GHG emissions reductions from the yield increases in GE crops are substantial and should be included in future analyses.