Improvement of nutritional value of crops is one of the main goals of plant biotechnology.These studies are extremely important for sorghum-a unique drought-tolerant cereal crop that is of special importance for sustainable grain production in the arid regions.The major cause of relatively low nutritive value of sorghum grain is the resistance of one of its seed storage proteins, γ-kafirin, to protease digestion.Using Agrobacteriummediated genetic transformation, we have obtained transgenic sorghum plants harboring a genetic construct for RNA interference (RNAi) silencing of the γ-kafirin gene.In T 1 generation, transgenic plants with modified endosperm texture were found.These plants had lowered level of the 28-kDa γ-kafirin protein and kafirin oligomers, which are formed by natural kafirin polymerization.In vitro protein digestibility analysis showed that the amount of undigested protein in transgenic plants was reduced by 2.9-3.2times, in comparison with the original line, the digestibility index reached 85-88% (60% in the original line).HPLC analysis showed that total amino acid content in transgenic plants was reduced, while the lysine proportion was increased by 1.6-1.7 times.PCR analysis confirmed inheritance of the genetic construct up to T 4 generation.
Earth today is experiencing visible climate changes, the one battle for which the humans are still not prepared enough to win. Existing economic, social, and cultural discrepancies between developing and developed countries are a constant obstacle for the “way forward,” and the decisions about environment, food, and education brought today will influence our children tomorrow. This book is intended for those who still believe that our greatest strength is actually our curiosity. Basic research scientists worldwide are constantly struggling to obtain enough, mostly public, funds to provide sound foundations for innovations in all aspects of life; however, the pressure to publish first occasionally neglects the fact that every creative idea needs a considerable amount of time to be realized, often with negative results. Although the criticism in science is always welcomed, whether it comes from the fellow scientists or from the public voice, due to the lack of understanding, the complicated problems we are trying to solve become even more difficult. For example, if tomorrow the bacterium Xylella fastidiosa, outlined by Alyson Abbott in Nature (8 June 2017) as a huge problem for the olive groves in Southern Italy, spread to the rest of Europe, the only measure would be to uproot the contaminated plants. Although the infection could have been stopped/decelerated years ago, environmentalists challenged scientific findings and fight against contaminated olive plants uprooting. Italy has already allocated more than 5 million euros for the containment measures and will be forced to increase the funding in the future. We should ask ourselves, “Could we rely on science to find a more creative solution?”
Development of vascular tissue is a remarkable example of intercellular communication and coordinated development involving hormonal signaling and tissue polarity. Thus far, studies on vascular patterning and regeneration have been conducted mainly in trees—woody plants—with a well-developed layer of vascular cambium and secondary tissues. Trees are difficult to use as genetic models, i.e., due to long generation time, unstable environmental conditions, and lack of available mutants and transgenic lines. Therefore, the use of the main genetic model plant Arabidopsis thaliana (L.) Heynh., with a wealth of available marker and transgenic lines, provides a unique opportunity to address molecular mechanism of vascular tissue formation and regeneration. With specific treatments, the tiny weed Arabidopsis can serve as a model to understand the growth of mighty trees and interconnect a tree physiology with molecular genetics and cell biology of Arabidopsis.
Plant small RNAs (sRNAs) are pivotal regulators of gene expression, which are crucial in maintaining genome integrity and flexibility during development, abiotic and biotic stress responses. Current evidence suggests that sRNAs might be inherent to the sophisticated plant innate immune system battling bacteria. However, the role of sRNAs during anti ‐ fungal plant defences is less clear. Therefore, this chapter investigates the sRNA‐mediated plant antifungal responses against the hemibiotrophic fungi Colletotrichum higginsianum and Colletotrichum graminicola in their respective compatible hosts Arabidopsis thaliana and Zea mays. A phenotypic and metabolomic analysis of A. thaliana sRNA mutants in response to C. higginsianum infection was performed, showing a hormonal and meta‐ bolic imbalance during fungal infection in these plants. To find whether fungal-induced sRNA could directly regulate defence genes in an agricultural important plant model, the expression of maize miRNAs in response to C. graminicola leaf and root infections was investigated. The results revealed the tissue-specific local and systemic adaptation of the miRNA transcriptome, where only a few miRNAs were targeting defence pathways. The general picture presented here points towards a role of sRNAs as fine-tuners of genetic and metabolomic defence response layers. This chapter also further discusses the poten ‐ tial of utilizing sRNA-based fungal control strategies.
High operational costs of greenhouse production in hot and humid climate condition due to the initial investments on structure, equipment, and energy necessitate practicing advanced techniques for more efficient use of available resources. This chapter describes design and concepts of an adaptive management framework for evaluating and adjusting optimality degrees and comfort ratios of microclimate parameters, as well as predicting the expected yield in greenhouse cultivation of tomato. A systematic approach is presented for automatic data collection and processing with the objective to produce knowledge-based information in achieving optimum microclimate for high-quality and high-yield tomato. Applications of relevant computer models are demonstrated through case-study examples for use in an iterative way to simulate and compare different scenarios. The presented framework can contribute to future studies for providing best management decisions such as site selection, optimum growing season, scheduling efficiencies, energy management with different climate control systems, and risk assessments associated with each task.
The nature of Hd3a protein in rice and its ortholog FT in Arabidopsis as a florigen has been proposed. However, molecular mechanism of its function still remains to be investigated. Therefore, it is important to search their interaction partners to better understand their signaling in flowering. As a long-distance signal that moves along leaf cells and the vascular system of leaves and stem and exerts its action in apical buds, it is important to determine the possible mediators of such common responses activated by Hd3a. To search Hd3a interactor, yeast two-hybrid screening have performed by using a cDNA library. A wide range of Hd3a interacting proteins involved in signaling were identified, including GF14c, OsKANADI and the BRI1 kinase domain interacting protein 116b (BIP116b). To reveal its function, Hd3a recruits different protein in plant developmental stage. It is possible that Hd3a and its partner(s) may form a platform for cross-talk between signal transduction pathways. Another homolog of Hd3a in many plants was identified and sugessted that Hd3a/FT has versatile role in plant development. This role depend on its partner and interaction to achieve its function. Our understanding in floral transition in rice would make for better crop management in future.
In plant breeding programs, one of the oldest methods is mutation breeding. Currently, mutation breeding has became popular among the breeders and scientists again with its use in plant biotechnology and due to some restrictions on the other techniques such as hybridization, cross breeding, and transgenic plants. Physical mutagens (X-rays, UV light, neutrons-alpha-beta particles, fast and thermal neutrons, especially gamma rays) are used more widely than chemical (ethyl methanesulfonate [EMS]) ones to artificially induce mutations (mutagenesis). However, among the physical mutagens, gamma-rays are widely used. During the irradiation of the seeds with ionizing radiation to generate mutants with desirable traits, reactive oxygen species (ROS) or free radicals can generate in cells. Although, these radicals/species generally can be very dangerous for the cell compartments, they can take an important role as a signal molecule activation of genes of antioxidant enzymes and proline, which are defense systems against these radicals in plant cells. In this chapter, usability of gamma-irradiation to provide the permanent gene expression of antioxidant enzymes and proline through the production of reactive oxygen species (ROS) is discussed.
World population is increasing day by day and at the same time agriculture is threatened due to natural resource degradation and climate change. Production stability, agricultural productivity, income and food security is negatively affected by changing climate. Therefore, agriculture must change according to present situation for meeting the need of food security and also withstanding under changing climatic situation. Projected estimates based on food consumption pattern and population growth show that agriculture production will require enhancing by 65% to meet the need of burgeoning population by 2050. Agriculture is a prominent source as well as a sink of greenhouse gases (GHGs). So there is a need to modify agricultural practices in a more sustainable way to overcome these problems. Developing climate‐resilient agriculture is thus crucial to achieving future food security and climate change goals. It helps the agricultural system to resist damage and recover quickly by adaptation and mitigation strategies. Mitigation strategies reduce the contribution of agriculture system to greenhouse gas emission, and adaptation strategies provide agriculture production under changing scenarios. This chapter explains different mitigation and adaptation strategies, including farming practices and engineering approaches.
