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Determining and improving drought-tolerant cultivars is a major goal of plant breeding to face climate change. The productivity of faba bean in Egypt is affected by abiotic stresses, especially drought stress. This study evaluated eight Egyptian faba bean cultivars for drought tolerance under three soil water regimes consisting of well-watered (100% field capacity), moderate drought stress (50% field capacity), and severe drought stress (25% field capacity) regimes in pots under greenhouse conditions using biochemical, physiochemical, and molecular parameters. The cultivars Nubariya 1, Nubariya 3, and Giza 716 showed the highest proline content values under 50% field capacity conditions, with 4.94, 4.39, and 4.26 mmol/g fresh weights, respectively. On the other hand, the cultivars Sakha 1, Sakha 4, Nubariya 1, and Nubariya 3 exhibited the highest proline contents (7.8, 7.53, 6.17, and 6.25, respectively) under 25% field capacity treatment. The molecular profiling was conducted using SCoT and SRAP approaches. Fresh leaves were utilized to extract the DNA, and ten primers for SRAP and six for SCoT were used in the PCR procedures. SCoT and SRAP-PCR generated 72 loci, of which, 55 were polymorphic, and 17 were monomorphic. SCoT and SRAP each had 48 and 24 total loci, respectively. The average polymorphism (%) values achieved via SCoT and SRAP were 70.93% and 80%, respectively. Based on the molecular profiles, the cluster analysis identified three clusters. The first cluster comprised Giza 716 cultivars; the second cluster included Sakha 1, Sakha 3, Sakha 4, and Akba 3300 cultivars; the third cluster comprised two cultivars Nubariya 1 and Nubariya3. According to the study’s findings, Sakha 1, Sakha 4, Nubariya 1, and Nubariya 3 are remarkable parents for developing drought-tolerant faba bean genotypes. Additionally, this study concluded that SRAP and SCoT markers recreated trustworthy banding profiles to evaluate the genetic polymorphism among faba bean cultivars, which are regarded as the cornerstone for genetic improvements in crops.

Nanotechnology is a great and promising future science for pressing global climate change solutions and increasing the global population through its various uses. This chapter conversed the implementation of nanotechnology in various environmental, medical and agricultural fields. In addition, it discussed the application of various nanoparticle biosynthesis as fertilizers in multiple forms including soaking, foliar fertilization and soil fertilization. Then explained in more detail the effectiveness of NPs such as (nano silicon, zinc oxide NPs, titanium dioxide NPs, silver NPs) on crop growth, phenological and physiological development under abiotic stress. Also, this chapter highlights the Mechanism of NPs uptake and accumulation in crops. Therefore, nanotechnology offers an effective application to reduce pollution, management of soil nutrients and achieve sustainable development.

The necessity of novel technologies to address the long-standing and worsened status of food security and sustainable agriculture is out of the question. Of the most recent promising approaches to alleviate constraints of the increasing occurrence of biotic and abiotic stressors on crop plants in the climate change era is nanobiotechnology involving potent methodologies with a large spectrum of applications covering both biotechnology and agriculture. Versatility of nanotechnology has made possible the establishment of quite a few biosensors that allow not only plant signaling biomolecules to communicate and actuate visually electronic monitoring devices to assess health status in real-time but also facilitates the allocation of resources. These include water and agrochemicals efficiency prior to the occurrence of water-deficit, salinity, extreme temperatures as well as phytopathogen-associated stress in order to maximize crop productivity and, consequently economical gains. Being new to the field of agriculture, achievements may not be commonly accessible worldwide. However, significant steps have been taken and reports are accumulating in relation to the development of nano biosensors for real-time monitoring. Particularly, using genetically encoded sensors that facilitate and accelerate the progress in this field by markedly improving current understanding of communications in stressed plants at the cellular level, the deciphering of which has been the purpose of plenty of recent biological studies. Nevertheless, a significant amount of research is required to optimize the application of nanomaterials to enhance feasibility of sustainable agriculture. This chapter aimed to summarize the most recent approaches to develop nano biosensors to bring worldwide food security into reality as the consequences of climate change become more tangible.

Abiotic stresses severely affect plant growth, development, production and quality. These stresses are the main reason for decreased productivity worldwide accompanied by an increasing human population. This necessitates developing novel solutions to achieve sustainability and overcome these problems. Recently, a new era has begun to emerge, the era of nanotechnology. It improved the ability crops to deal with abiotic stress and primary or secondary metabolic function. The present chapter provides insight on the relationship between abiotic stresses and nanotechnology together with nanofertilizers, their characteristics/roles as well as their comparison with conventional fertilizers. Moreover, this chapter not only highlights the interaction between NPs and plants on several growth stages, but also the importance of nanotechnology in the purification of irrigation water, the effect of different nanoparticles on crops cultivated under abiotic stress with their possible toxicity impact on plants.

Beetroot, table beet, red beet or garden beet (Beta vulgaris ssp. vulgaris var. conditiva Alefeld) is a cross-pollinated crop that belongs to the family Chenopodiaceae. It is one of the most essential and economical cultivated vegetables. Globally, beetroot is used for food products, pickles, salads and juice rather than for sugar production. Also, edible sugar can be extracted from the root. Gene banks have conserved a wide variety of genetic resources from beetroot including wild species. There are several species with various chromosome numbers. Beta harbors significant diversity based on geographic regions and morphological features. Introgression of novel alleles by crossing different genetic resources for the beetroot e.g. crossing common varieties with locally developed varieties increases genetic diversity and pre-selects for useful traits. It is necessary to ensure ample natural variation in phenotypes. The key goals of breeders and geneticists are to improve beetroot for different desirable traits including tolerance to biotic and abiotic stress, quality and yield characteristics. Applying modern genetic tools to improve conventional breeding programs can further the achievement of these goals. This chapter provides an overview and limitations of the beetroot germplasm biodiversity and conservation, objectives and stages of beetroot breeding programs and conventional breeding methods. Additionally, it addresses modern methods of plant breeding, including marker-assisted breeding and genetic engineering.

Evolution has long enabled plants with an adjusted response and tolerance mechanisms in the time facing drought, salinity, extreme temperatures, excessive light, and heavy metals collectively known as abiotic stress, with an accelerated incidence in climate change era owing to a rapid rise in global temperature, which has triggered a domino effect that recent studies announced its destructive influence on agricultural products. These circumstances have exposed crops to an unprecedented level of multi stress that involves a plethora of complicated morphological, physiological and molecular responses as well as survival strategies. The changes assist plants to improve water relations, regulation over oxidative stress and osmotic adjustment and induction of genes that are directly or indirectly initiate networks of signaling to organizational readiness for an arms race in plants against stress-generated harmful products. Its intertwined nature has been the subject of plenty of biological studies to reach a reliable realization of these processes, since this is the safe approach to inject this understanding into selection and breeding programs to create superior cultivars that make a human capacity to provide food to an ever-increasing population on the earth.

In their life cycle, plants face a range of environmental stresses such as heat, cold, drought, salinity, etc., which greatly affects the performance of the plant and is one of the key factors in the distribution of plant species. Plants use special mechanisms to withstand these stresses. When plants are exposed to stress, the information is transmitted by the signal transduction pathway, and eventually, the response to these signals leads to physiological and biochemical changes in the plants. Usually, one type of stress is accompanied or followed by other stresses. For example, heat stress is followed by drought stress due to physical loss of water, and cold stress is followed by drought stress due to the physiological inaccessibility of water. Due to the large number of environmental hazards that the plant faces at a particular time, abiotic stress signaling is a very complex phenomenon. Plants have tools to avoid and deal with these stressors. On the one hand, they can produce inductive and appropriate responses that lead to a specific desired change for which special stress conditions are specialized. On the other hand, there is a significant overlap between the components of abiotic stress signaling and the starting points in which the pathways for stress signaling are coordinated. In this chapter summarized, how abiotic stresses in plants can be tolerated.

This chapter is focused on the achievements and future prospects of cotton breeding and related biotechnology. Traditional plant breeding has been utilized for the development of pure-line selection for high yielding cotton genotypes in segregating generations through the pedigree method. Selection criteria include boll number plant−1, boll mass, sympodial branches and ginning outturn percentage. Plant breeder efforts have been fruitful in releasing cotton cultivars with high yield potential and superior lint quality traits. Traditional breeding efforts resulted in the increase of seed cotton yield and fiber length. The calculated increase in the yield potential was 1.34 kg ha−1 year−1. However, further genetic gains due to selection for high-yield potential reached a plateau in the last two decades and the recent increase in yield was due to better cotton husbandry techniques. Cotton ideotypes specifically for various agronomic and environmental conditions may be developed. Moreover, utilization of wild relatives for the introgression of disease resistance and abiotic stress tolerance is proposed through traditional plant breeding along with molecular markers to reduce linkage drags due to wild relatives. These high yielding cultivars with superior agronomic and adaptability traits may be further used for the development of transgenics. Genome editing technique such as CRISPR/Cas (clustered regularly interspaced short palindromic repeats: associated protein) is one of the emerging technologies to knock out genes or SNP (single nucleotide polymorphism) substitution at specific site with future prospects for the development of disease resistant crop cultivars.

Date palm is one of the oldest cultivated plants, grown in the arid and semiarid regions of the world. The date fruit serves as a vital worldwide component of the human diet and a staple food for millions of people. Unfortunately, various abiotic and biotic stresses along with agronomic constraints are hindering date productivity. Those date cultivars adapted to stress conditions have low fruit production. Conventional breeding, depending on crosses and backcrosses, is a time-consuming process. The applied research carried out on date palm is limited, still there is enormous potential to improve date palm breeding methods. Advanced biotechnology creates unparalleled opportunities to develop new varieties with quality fruit, increased fruit yield and resistance to pests and pathogens. It also minimizes the application of potentially-harmful fungicides and pesticides and increases crop productivity. This chapter provides current and innovative information about date palm progress in terms of distribution, production, marketing strategy, current achievements, limitations and challenges facing date palm breeding. It also focuses on recent advances in tissue culture, genetic transformation and molecular breeding to improve the productivity and quality of the date.

Date palm is one of the major crops growing in regions where abiotic stress conditions are extreme. Abiotic stress affects plant growth, development, physiology, and biochemical processes. This chapter describes a protocol to evaluate the response of date palm cultures to abiotic stresses. Tolerance to salinity stress is assessed using calcium chloride (CaCl2), potassium chloride (KCl), and sodium chloride (NaCl) at 11.96, 12.06, and 9.45 g/L, respectively (equivalent to 0.8 MPa osmotic potential), with different exposure durations (1-12 days). Polyethylene glycol (PEG 8000) is tested at 0-30% (w/v) to assess tolerance to drought stress. Techniques are described to define the effects of these stress agents on the growth of callus and cell suspension cultures, water content, proline accumulation, and Na+ and K+ content ratio, in addition to the technique used for determining the median lethal dose (LD50) for PEG (29.5%) and NaCl (11.54 g/L). This protocol will be useful for future studies of in vitro selection of tolerant cell lines.

World poverty and hunger are closely related toenvironmental degradation, caused by increasingpopulation pressure and urban expansions, soilerosion, limitation of water resources, gaseouspollution, and massive industrialization.Furthermore, climate changes and extreme weatherpatterns pose new challenges for crop productionand food security. Sustainable agriculture for theproduction of food and fiber, usingenvironmentally-conscious farming practices basedon understanding plant ecological interactions, iscrucial for the preservation of natural resources forfuture generations.This special issue focuses on recent researchprogress on understanding plant interaction withabiotic and biotic stress factors for sustainableagriculture. Plant stresses inflected by salinity,drought, floods, temperature extremes, radiation,and toxic substances deposited in the soil togetherwith diseases and insects attacks, are the majorlimitations of crop cultivation incurring substantialreduction in yield and hence elevate economiclosses to the farmers.Sustainable agriculture is challenged by thelosses in crop genetic diversity. Conservation ofavailable germplasm and the efficient utilization ofgenetic resources are important aspects of currentresearch. In this special issue, Yumurtaci (2015)reviewed the utilization of wild relatives for thedevelopment of abiotic and biotic stress tolerantnew varieties of four major food crops includingwheat, barley, maize and oat.Modern advances in biotechnology offerinnovative approaches for understanding thefundamental mechanisms of abiotic and bioticstress and the development of stress tolerant crops.On this topic, Bakhsh (2015) reviewed currentresearch achievements towards the development ofabiotic stress tolerant crops through geneticengineering. In addition, Ram and Sharma (2015)studied the molecular characterization of TaPase inwheat, a gene known to be involved in plantresponse to stress.Plant diseases represent another major challengefor sustainable agriculture. To illustrate theimportance of integrating genetic engineering in thestrategies to combat plant diseases, Elayabalan etal. (2015) reviewed relevant advances in thedevelopment of banana plants resistant to thebanana bunchy top disease.Moreover, crop plants must adapt to adverseclimatic conditions, particularly those associatedwith the global climatic changes. Stresses due toabiotic stress factors like drought, extremetemperature and salinity and heavy metal toxicityinflect tremendous losses in crop productivity andare considered as major challenging factors forfuture agriculture sustainability. This topic wasaddressed in this special issue in several papers.Ud-Din et al. (2015) addressed drought effect onrice yield in relation to hormonal application.Siddika et al. (2015) studied the response to hightemperature stress of Basella alba, a leaf vegetablecommonly names as vine spinach.On the topic of heavy metal toxicity, Fasahat(2015) reviewed progress made in understandingcadmium toxicity and tolerance in rice. The specialissue also include studies on nutrient uptake fromunder saline conditions in potato (Oustani et al.,2015) and ion content in wild sage (Lantanacamara) treated with mepiquat chloride applicationunder shading (Matsoukis et al., 2015). In additionAjambang et al. (2015) examined the response ofoil palm to defoliation stress. Obviously,understanding abiotic and biotic stress mechanismsis essential for the development of tolerant cropcultivars under the global climate change.ReferencesAjambang, W., S. W. Ardie, H. Volkaert, M.Galdima and S. Sudarsono. 2015. Hugecarbohydrate assimilates delay response tocomplete defoliation stress in oil palm (Elaeisguineensis Jacq.). Emir. J. Food Agric.27(1):126-137.Bakhsh, A. 2015. Genetic engineering of cropplants against abiotic stress: Current

High temperature is recognized to be a major abiotic stress involved in di verse metabolic regulation in plants. However, the regulatory mechanism of high temperature induced polyphenol oxidase (PPO) activity in Basella alba is not clarified. B. alba plants grown in pots were exposed to 45°C for 24, 48 and 72 h periods and the control plants were kept at 30°C. The PPO activity in leaves of plants was up regulated and the effects were more pronounced at 24h of treatment. To clarify the regulatory mechanism of enhancing the effect, plants were treated with 10 mM Na2HAsO4 and exposed to 45oC for the above mentioned periods. Na2HAsO4 along with high temperature causes similar stimulatory effects of PPO activity when compared to respective control. Therefore, both high temperature and arsenic treatment may cause additive stresses and en hance the PPO activity. To further clarify the mechanism of high temperature induced PPO activity, plants were treated with 1 mM Nifedipine, a recognized calcium channel blocker and exposed to 45oC. Treatment with blocker effectively prevented the activity induced by high temperature almost to the control level which shows clearly that high temperature-induced activity is mediated through calcium channel and may affect cellular concentration of calcium. The results suggests that increased PPO activity might be due to oxidative stress and that arsenic and calcium play a critical role in this phenomenon, thereby the plants survive in adverse environment .

The advent of agricultural biotechnology offers new approaches for the genetic improvement of date palm (Phoenix dactylifera L.), an important economic fruit crop in arid regions. In vitro studies were conducted to recover date palm plants exhibiting enhanced tolerance to salinity and drought stress, two major agricultural problems in arid areas. The response of date palm callus cultures to salt stress was investigated by exposing cell suspension and callus cultures to varying concentrations of sodium chloride (NaCl). The reaction of callus to the duration of exposure to NaCl, potassium chloride (KCl) and calcium chloride (CaCl2) was evaluated. Similarly, drought tolerance was assessed in response to varying concentrations of polyethylene glycol (PEG-8000). Significant differences were reported in various parameters measured including callus growth, somatic embryogenesis, proline content and ion distribution. Calli with enhanced tolerance to these selection agents were obtained; however, plant regeneration from these cell lines was not realized. Although the available data provide an insight of the behavior of date palm callus in the presence of salt and drought stress, further research work is required to refine the selection procedures and plant regeneration from the selected tolerant cell lines.