Transplastomic plants for innovations in agriculture. A review

Abstract

Food production has to be significantly increased in order to feed the fast growing global population estimated to be 9.1 billion by 2050. The Green Revolution and the development of advanced plant breeding tools have led to a significant increase in agricultural production since the 1960s. However, hundreds of millions of humans are still undernourished, while the area of total arable land is close to its maximum utilization and may even decrease due to climate change, urbanization, and pollution. All these issues necessitate a second Green Revolution, in which biotechnological engineering of economically and nutritionally important traits should be critically and carefully considered. Since the early 1990s, possible applications of plastid transformation in higher plants have been constantly developed. These represent viable alternatives to existing nuclear transgenic technologies, especially due to the better transgene containment of transplastomic plants. Here, we present an overview of plastid engineering techniques and their applications to improve crop quality and productivity under adverse growth conditions. These applications include (1) transplastomic plants producing insecticidal, antibacterial, and antifungal compounds. These plants are therefore resistant to pests and require less pesticides. (2) Transplastomic plants resistant to cold, drought, salt, chemical, and oxidative stress. Some pollution tolerant plants could even be used for phytoremediation. (3) Transplastomic plants having higher productivity as a result of improved photosynthesis. (4) Transplastomic plants with enhanced mineral, micronutrient, and macronutrient contents. We also evaluate field trials, biosafety issues, and public concerns on transplastomic plants. Nevertheless, the transplastomic technology is still unavailable for most staple crops, including cereals. Transplastomic plants have not been commercialized so far, but if this crop limitation were overcome, they could contribute to sustainable development in agriculture.

Drought stress and carbon assimilation in a warming climate: Reversible and irreversible impacts

“…The response of different genotypes of the same crop species to drought or heat periods may vary in wide range (Vassileva et al, 2009(Vassileva et al, , 2011(Vassileva et al, , 2012Erice et al, 2010Erice et al, , 2011Yin et al, 2010 ;Parry et al, 2011;Prior et al, 2011;Cao et al, 2014 ;Habash et al, 2014;Topbjerg et al, 2014;Acuna-Galinda et al, 2015 ;Lopes et al, 2015;Wani et al, 2015;Wehner et al, 2015). This is the basis for breeding of crop varieties with a better performance under abiotic stresses.…”

Cost of agronomic biofortification of wheat with zinc in China

“…However, more than half of wheat plantation is in Zn-deficient soils and the Zn concentration in wheat grain is generally too low to supply sufficient Zn nutrition for human health (Alloway 2008;Cakmak 2008). Therefore, more attention has been paid to the improvement of human Zn intake by biofortification of wheat grain with Zn (Schroeder et al 2013;Wheeler and von Braun 2013;Myers et al 2014;Wani et al 2015). The genetic biofortification via breeding Zn-enriched wheat varieties represents a long-term strategy with important advantages.…”

Production of dengue virus envelope protein domain III-based antigens in tobacco chloroplasts using inducible and constitutive expression systems

“…The fusion protein approach indicates a way to avoid unbalanced immune responses continuously reported for tetravalent formulations consisting of stoichiometrically mixed monovalent vaccines (Capeding et al 2014;Hadinegoro et al 2015;Villar et al 2015). Furthermore, the transformation of the plastid genome represents a promising possibility for the high-level, cost-effective, clean and safe expression of therapeutically relevant proteins in commercial applications (Wani et al 2015). A theoretical technoeconomic case study showed that plants can be highly competitive production platforms for biopharmaceuticals (Tuse et al 2014).…”