Genetic Engineering and Sustainable Crop Disease Management: Opportunities for Case-by-Case Decision-Making

Abstract

Genetic engineering (GE) offers an expanding array of strategies for enhancing disease resistance of crop plants in sustainable ways, including the potential for reduced pesticide usage. Certain GE applications involve transgenesis, in some cases creating a metabolic pathway novel to the GE crop. In other cases, only cisgenessis is employed. In yet other cases, engineered genetic changes can be so minimal as to be indistinguishable from natural mutations. Thus, GE crops vary substantially and should be evaluated for risks, benefits, and social considerations on a case-by-case basis. Deployment of GE traits should be with an eye towards long-term sustainability; several options are discussed. Selected risks and concerns of GE are also considered, along with genome editing, a technology that greatly expands the capacity of molecular biologists to make more precise and targeted genetic edits. While GE is merely a suite of tools to supplement other breeding techniques, if wisely used, certain GE tools and applications can contribute to sustainability goals.

Antimicrobial Activity of <i>Tithonia diversifolia</i>, <i>Elephantopus scaber</i>, and <i>Kigelia africana</i> Against Plant Pathogens

“…Intensive use and inappropriate dose of these pesticides for the control of plant pathogens may raise harmful impact on the environment and adverse effects on human health [1]. Therefore, it is a challenge in agricultural practices, particularly in disease management that ideally support and contribute to the sustainability of disease management through protecting crop yields, maintaining and improving profitability for crop producers, and reducing the negative environmental impacts of diseases [2]. Alternatively, several techniques to control plant disease have been developing with low negative impact on environment with high efficacy such as the use of biological control agent or natural products that are grouped to biopesticides [3].…”

Identification, Mapping and Pyramiding of Genes/Quantitative Trait Loci (QTLs) for Durable Resistance of Crops to Biotic Stresses

“…Bacteria, viruses, fungi, nematodes, insect pests and weeds are considered to be biotic factors that limit crop production [2][3][4]. For years, chemicals have been used to control biotic damage of crop plants.…”

“…Nowadays, interest in the use of chemicals against biotic stress is decreasing because of its various limitations such as the requirement for more than one chemical application, an investment that is not affordable by most small-scale farmers [5]. Besides, using chemical spray may have adverse effects on human health and the environment, including beneficial organisms and may lead to the development of chemical-resistant pathogen races, insects, and weeds [4,6]. On the other hand, the use of resistant cultivars is currently seen as the best strategy, durable, economical, and environmentally friendly means of biotic stress control [7][8][9].…”

Sustainable Agriculture—Enhancing Environmental Benefits, Food Nutritional Quality and Building Crop Resilience to Abiotic and Biotic Stresses

“…Cultural practices such as crop rotation, alteration of planting date, etc. certainly play a role in pathogen and pest management but the level of control is often inadequate or economically nonviable [68]. For example, to decrease fungicide use in oilseed rape production an effective biological control strategy must be developed for the important soil-borne pathogen Sclerotinia sclerotiorum as the other forms of disease control tactics for this pathogen can be inadequate.…”

“…Traditional breeding strategies for plant resistance to pathogens have successfully mined 'R' (resistance) genes from related plant hosts and incorporated them into high yielding cultivars [68,160]. Research carried out to understand plant-pathogen interactions helped the discovery of plant 'R' genes that contained pathogen attack via 'innate' immunity.…”