Auswahl der wissenschaftlichen Literatur zum Thema „Wheat Drought resistance“

Selection for drought tolerance typically involves evaluating genotypes for either high yield potential or stable performance under drought stress. In order to select drought tolerant varieties of bread wheat an experiment was conducted in a randomized complete block design (RCBD) with two replications during the growing season 2014-2018. Eight drought tolerance indices including stress tolerance index (STI), geometric mean productivity (GMP), mean productivity index (MP), stress susceptibility index (SSI), tolerance index (TOL), yield index (YI), yield stability index (YSI) and drought resistance index (DI) were calculated and adjusted based on grain yield under drought years (Ys) and favorable years (Yp). Result of study showed significant positive correlation between grain yield in the stress condition (Ys) with indicators STI, GMP, TOL, MP, and DI, accordingly they are discriminating drought tolerant genotypes at the same manner. Wheat varieties Darkhan-172, Darkhan-72, Altaiskaya-325, Altaiskaya-70, Darkhan-181 has a high yield potential. Genotypes Darkhan-160, Arvin, Darkhan-144 most droughts tolerant and can be use in wheat breeding for improving drought resistance. Зусах зөөлөн буудайн сортуудыг ган тэсвэрийнүнэлэмжээр үнэлсэн дүнгээс Судалгаагаар манай оронд өргөн тариалагдаж байгаа өөрийн орны селекцээр гаргасан болон гадаадын нийт 20 сортонд ган тэсвэрийн индекс:стресс тэсвэрийн индекс (SТI), тэсвэрийн индекс (TOL),стресс мэдрэмжийн индекс (SSI), ган тэсвэрийн индекс (DI)-ээрүнэлгээ өгсөн. Зусах зөөлөн буудайн ургац ба ган тэсвэрийн индексүүдийн хооронд эерэг нягт хамааралыг тогтоосон. Чийгийн хангамж сайтай жилд потенциаль ургацаар буудайн эртийн болцтой Дархан-172, дунд-эртийн болцтой Дархан-72, Алтайская-325, Алтайская-70, дунд оройн болцтой Дархан-181 сортууд шалгарсан ба эдгээр сортуудыг селекцид хагас эрчимжсэн сорт гаргахад ашиглаж болно. Ган тэсвэр өндөртэй сортыг бий болгоходселекцид эртийн болцтой Дархан-160, дунд-эртийн болцтой Арвин, дунд оройн болцтой Дархан-144 сортуудыг эх материалаар ашиглаж болно. Зусах буудайн Дархан-144 сорт нь гадаад орчны нөхцөлд дасан зохицох чадвар сайтай сортоор шалгарав. Түлхүүр үг: болц,сорт, ургац, стресс, индекс

Scarcity of water has been a serious agricultural hindrance to crop productivity since antiquity. Drought-stressed loss in wheat yield likely exceeds losses from all other causes, since both the severity and duration of the stress are censorious. Here, we have reviewed the effects of drought stress on the morphological, physiological, and biochemical attributes along with the growth impacts, water relations, and photosynthesis impacts in wheat. This review also illustrates the mechanism of drought resistance in wheat. Historical drought years in Nepal have been identified and the yield losses were assessed. Wheat encounters a variety of morphological, physiological, biochemical responses at cellular and molecular levels towards prevailing water stress, thus making it a complex phenomenon. Drought stress affects leaf size, stems elongation and root proliferation, imbalance plant-water relations and decline water-use efficiency. Different types of physiological research are ongoing to find out the changes occurs in the wheat plant as a result of drought stress. Morphological changes can be looked through two ways: changes in root system and changes in shoot system such as effects on height, leaf senescence, flowering, and so on. Physiological changes involve changes in cell growth pattern, chlorophyll contents, photosynthetic disturbances, plant-water relations, etc. Biochemical changes occur in different chemical, biomolecules, and enzymes. Plants portray several mechanisms to withstand drought stress which can be classified as Drought escape, Drought avoidance, and Drought tolerance. Selection of wheat genotype that can tolerate water scarcity would be suitable for the breeding program aiming to development of drought tolerant variety under water limited regions.

Drought represents the most devastating abiotic stress factor worldwide. It severely limits plant growth and development as well as agricultural characteristics including the final yield. The aim of this review is to summarise recent results of the breeding of barley (Hordeum vulgare) and wheat (Triticum aestivum; T. durum) for improved resistance to drought stress. First, drought-associated terms and definitions are outlined and plant strategies to cope with drought are presented. A brief overview of plant physiological mechanisms involved in water uptake and release is provided. Photosynthesis-related parameters (CO₂ availability and associated features such as ribulose-1,5-bisphosphate carboxylase/oxygenase activity, ¹³C discrimination activity, water use efficiency) are discussed due to the crucial role of plant leaf stomata in both photosynthesis and water management. The second part describes the present state of research on drought resistance-associated traits in barley and wheat. Different strategies of plant water management aimed at maximising the final yield under various types of drought stress are discussed. Possibilities of the detection, identification and characterization of quantitative trait loci (QTLs) in barley and wheat germplasm are discussed and the future approaches to breeding for enhanced drought resistance as a complex physiological and agronomical trait are outlined.

Drought is a widespread abiotic stress that has a detrimental effect on both yield and quality of wheat. Discovery and utilisation of drought-resistant gene resources from wheat-related species may help to mitigate effects of drought and decrease yield loss. In this study, we used a comparative proteome approach to identify potential drought-resistance proteins from a wheat (Triticum aestivum L.)–Haynaldia villosa (L.) Schur 6VS/6AL translocation line. Drought experiments showed that introgression of the H. villosa 6VS chromosome short arm into common wheat cultivar Yangmai 5 through 6VS/6AL translocation led to better drought resistance. Two-dimensional difference gel electrophoresis (2D-DIGE) identified 99 differentially accumulated protein (DAP) spots in the wheat–H. villosa 6VS/6AL translocation line, 42 of which were specifically present or showed a significantly upregulated accumulation. Of these, 20 DAPs representing 19 unique proteins in the wheat–H. villosa 6VS/6AL translocation line were upregulated under drought stress. These proteins were mainly involved in defence–stress, energy metabolism, carbon metabolism, nitrogen metabolism, and protein metabolism or folding. Protein–protein interaction analysis of key DAPs displayed a complex interaction network that synergistically regulated drought response. Dynamic transcriptional expression analysis revealed the differential expression of six key DAP genes involved in drought-stress response in the protein–protein interaction network. Our results indicated that H. villosa may have gene resources for wheat drought-resistance improvement.

Drought is one of the main disasters affecting wheat production. As a new type of plant hormone, SLs can effectively regulate the drought resistance of plants. However, so far, there are few studies on its effects on the growth and development of wheat. Aiming at the above situation, this study used foliar spraying to study its effects on the drought resistance metabolism of wheat under different concentration conditions. The results showed that exogenous SLs could not only improve root structure and promote root growth, but also increase the activities of enzymes such as SOD, POD and CAT in leaves, reduce the content of MDA, increase the content of Proline, and then improve the growth of plants. Water content, promote the improvement of photosynthetic pigments, and ensure the effective process of plant water and energy metabolism, thereby improving the drought resistance level of wheat at seedling stage. This study not only provides a theoretical basis for the application of SLs in wheat drought resistance, but also provides some technical support for its field cultivation in wheat.

One of the common features of the Mediterranean climate in North Africa is the uncertainty of rainfall immediately after wheat (Triticum durum Desf) emerges. Relatively little work has been done to compare the drought resistance of spring durum wheat cultivars under early-season drought stress. There is a limited insight into the physiological basis of spring durum wheat drought resistance in rainfed Mediterranean regions. Field experiments were conducted in 1995 and 1996 growing seasons, and a greenhouse experiment was conducted in 1996 to examine differences in some physiological characters among six spring durum wheat cultivars in response to different durations of early-season drought, and rewatering; and to determine the relationships of these characters to drought resistance. Six spring durum wheat cultivars were evaluated under four water regimes. Water regime treatments were: a well-irrigated treatment; and three water deficit treatments imposed during the period from emergence through either the onset of tillering, mid-tillering or the end of tillering. Cultivars differed widely in their response to early season water stress. Under drought stress conditions, grain yield, aboveground dry matter yield, water use efficiency for the grain (WUEg) and for the total dry matter (WUEdm) were strongly positively associated with net CO2 uptake:transpiration ratio (A/E), and osmoregulation capacity. It is concluded that drought-induced changes in A, A/E, stomatal resistance, and osmotic adjustment are possible key control points in determining the drought-resistance of a cultivar. Furthermore, there is a substantial degree of intraspecific variation for the above mentioned physiological attributes to explore as a selection tool. Selection for high osmoregulation capacity and high A/E ratio would seem to be a justifiable means of improving total dry matter and grain yield under conditions of early-season water stress. Key words: Wheat, Triticum durum Desf., physiological attributes, early-season drought

Drought is one of the most harmful environmental factors that adversely affect the growth of economically important crops and global food security. Its prevalence is increasing worldwide as a result of global warming and about one-third of the world land area is prone to drought. Droughts are also common in Pakistan that affects the agriculture. Wheat is the most important cereal crop in all over the world, but in Pakistan its yield is much lower than other countries. So, under this scenario there is a need to develop environment friendly approaches to mitigate the effects of drought stress for sustainable agricultural productivity. Use of organic matter can enhance soil moisture holding capacity and allow penetration of plant roots to access soil moisture and nutrients for higher crop yield. So, it is important to keep soil organic matter at reasonable levels to preserve the healthy soil. Cow dung manure and press mud both are good source of organic matter that can enhance nutrients and water holding capacity of soil. Silicon application can also improve the plant resistance to water deficiency under drought. Hence, the combine application of organic and inorganic amendments may be considered a practical approach to stimulate the growth and biomass of wheat crop under drought stress.

The relevance of drought and salinity stress under Mediterranean conditions is reviewed and prospects for crop improvement against these constraints are discussed. Field trials under severe drought in Syria highlighted the importance of earliness to ensure satisfactory yields. Peduncle length and frost tolerance were also important attributes. Under more favourable conditions in Sicily, the yield components per se (number of spikes, number of kernels and kernel weight) had greater influence on genotype performance. At both locations of evaluation high yields were attained through different architectures of traits. Durum wheat genetic resources proved very variable. Genotypes were identified which could be used as donors of adaptive characters in breeding programmes. The CERES-Wheat growth model was used for the two locations, using historical weather data and two genotypes of known adaptation to the region. Early heading was a positive attribute, particularly in Syria. At both sites, lengthening of the grain filling period resulted in higher yields. Three sowing dates were simulated. "Early" sowing (1 November) had the highest simulated yield in both environments, suggesting a possible agronomic means to improve yields under stress. Simulated yields were in most cases within 15% of measured values when a comparison was possible. The ability to adjust osmotically was sought in seedlings artificially exposed to drought stress during early development. One entry appeared to possess this feature. However, another genotype, of known tolerance under real conditions, did not show this ability. Therefore, osmotic adjustment during early stages of ontogeny does not seem unequivocally able to identify the best genotypes under drought. Salt tolerance of durum wheat genetic resources was assessed measuring early growth under controlled environment. The data indicated that the results may be somewhat experiment-specific when using different growing techniques such as hydroponics and sand-culture. Finding tolerant tetraploid entries in terms of plant survival and ion uptake seemed difficult. However, variability existed and some entries, less susceptible than others, were noted. They could be used for breeding. For instance, they could be valuable recipient for the introgression of identified resistance mechanisms from other taxa.

Drought is a major limiting abiotic stress influencing wheat production in many parts of the world. The erratic nature of water deficits makes breeding and selection for drought resistance deficient. In environments with late season drought stress, yield losses are usually associated with kernel abortion or reduction in kernel growth. Remobilization of soluble carbohydrates from the stem has been associated with drought resistance. The objectives of this investigation were i) to asses the role of soluble carbohydrates in the determination of drought resistance, ii) their association with productivity, and iii) to evaluate a rapid technique to identify genotypes with higher capacity of soluble carbohydrate remobilization. Nine winter wheat cultivars differing in their response to drought stress were grown under irrigated and nonirrigated conditions during the grain filling period at the Sherman Branch Experiment Station, Moro. The cultivars were also grown at the Hyslop Crop Science Laboratory, where plots were chemically desiccated with Sodium Chlorate or left untreated. All control and treated plots were evaluated for soluble carbohydrates in two vegetative fractions, stem plus sheath and leaf blades. These values were correlated with the relative reductions in kernel weight and yield observed on the treated plots. Differences among cultivars were observed for the concentration of soluble carbohydrates in the stem and leaf fractions. Time elapsed from anthesis was a major determinant of the variation in carbohydrates concentration observed during grain filling. Stem soluble carbohydrates accumulated to a much greater extent than leaf soluble carbohydrates. The concentration of stem carbohydrates was not related with the reductions caused by chemical desiccation or drought stress. However, potential contributions from stem reserves (ratio between potential spike weight and stem reserves) were marginally associated with drought resistance. Stem soluble carbohydrates were positively associated with productivity, suggesting that stems are not competitive sinks, but temporary storage organs of excess of assimilates. Under chemical desiccation most of the soluble carbohydrates were lost in respiration, and the reductions in kernel weight and yield observed were not correlated with those observed under drought. It was concluded that the technique did not reasonably simulated drought in terms of yield reductions nor carbohydrate remobilization.
Graduation date: 1998

Doctoral fellowship under the Doctoral Program “Agricultural Production Chains – from fork to farm” (PD/00122/2012) provided by the FCTPortuguese Foundation for Science and Technology (PD/BD/ 52543/2014).
O trigo (Triticum spp.) é uma das culturas mais importantes do mundo. A seca é um fator crítico na segurança alimentar mundial, e um dos mais importantes fatores limitantes na produtividade dos cereais. No contexto das alterações climáticas à escala global, esperam-se aumentos da temperatura média e da severidade da seca nas principais regiões produtoras de trigo, pelo que é urgente aumentar a resistência da cultura ao stresse hídrico. A aplicação exógena de microminerais e antioxidantes às plantas, através do pré-tratamento de sementes ou via aplicação foliar, é considerada uma estratégia eficaz para aumentar a resistência ao stresse e o conteúdo nutricional das plantas. Esta tese foca-se principalmente nas consequências do pré-tratamento de sementes e aplicação foliar de zinco (Zn) e ácido ascórbico (AsA) e, secundariamente, nos efeitos da aplicação de ferro (Fe) e piridoxina (Pyr). Neste estudo demonstramos que as cultivares antigas de trigo possuem características que lhes permitam germinar e resistir ao stresse hídrico. Em todo o caso, para atingir os objetivos do trabalho, selecionamos uma cultivar moderna - ‘Jordão’ - com rendimento elevado e estável, e boas características de germinação em vários potenciais hídricos. O pré-tratamento de sementes com Zn induziu inibição do crescimento, instabilidades citogenéticas e alterações na atividade nucleolar, tendo estes efeitos sido exacerbados em condições de stresse hídrico. A combinação de Zn e Fe na solução de pré-tratamento de sementes contribuiu para a redução das anomalias citogenéticas causadas pelo Zn. Esta combinação leva a uma diminuição nas anomalias citogenéticas e a efeitos benéficos a longo prazo, como o melhoramento do afilhamento e do rendimento. O pré-tratamento de sementes com AsA e Pyr também promoveu melhorias a longo prazo, melhorando o crescimento do trigo. Considerando que as alterações climáticas devem alterar a data de sementeira e reduzir o período de crescimento do trigo, esta melhoria pode ser valiosa. Também se demonstrou que o stresse hídrico severo induz a dissipação não regulada de energia, o que produz danos duradouros nos fotossistemas. O pré-tratamento de sementes isolado e / ou acoplados à aplicação foliar de Zn ou AsA foram capazes de melhorar a fotoproteção durante a seca, aumentando a dissipação regulada do excesso de energia e promovendo uma melhor recuperação das plantas de trigo após o alívio do stresse.
Wheat (Triticum spp.) is one of the most important crops worldwide. Drought is a critical factor in world food security and one of the most critical limiting factors for cereal productivity. In the context of global climate change is expected the increase of mean temperature and drought severity in major wheat growing regions, compromising wheat production. Considering the importance of wheat, improving this crop establishment and drought stress resistance is a challenge on a global scale. Exogenously application of microminerals and antioxidants by seed priming or foliar application is considered an effective strategy to enhanced stress resistance and plants nutritional content. This thesis focuses mainly on the consequences of seed priming and foliar application of zinc (Zn) and ascorbic acid (AsA) and, secondary, on the effects of iron (Fe) and pyridoxine (Pyr). We have shown that ancient wheat cultivars, may have key features that allow them to germinate and withstand drought stress. Still, for this study we selected a modern cultivar – ‘Jordão’ – with high and stable yield, and good germination characteristics across water potentials. Zn priming induced early growth inhibition, cytogenetic instabilities and modulated nucleolar activity, being these effects exacerbated under drought stress. The combination of Zn and Fe in the priming solution proven efficient in reducing the cytogenetic anomalies caused by Zn alone. This combination leads to a decrease in cytogenetic anomalies and long-term beneficial effects such as improved tillering and yield. Priming with AsA and Pyr also promoted a long-term improvement by enhancing wheat growth, from joining until heading. Considering that climate change is expected to change sowing time and decrease wheat’s growing season, this improvement might be valuable. We also showed that severe drought stress induces a non-regulated energy dissipation which most likely produced photo-damage and long lasting damaged to the photosystems. Priming alone and/or coupled with the foliar application of either Zn or AsA were able to enhance photoprotection during drought by increasing regulated dissipation of excess energy and promoting a better recovery of wheat plants after stress relief.

Nationalism: Past as Prologue began as a single volume being compiled by Ad Akande, a scholar from South Africa, who proposed it to me as co-author about two years ago. The original idea was to examine how the damaging roots of nationalism have been corroding political systems around the world, and creating dangerous obstacles for necessary international cooperation. Since I (Bruce E. Johansen) has written profusely about climate change (global warming, a.k.a. infrared forcing), I suggested a concerted effort in that direction. This is a worldwide existential threat that affects every living thing on Earth. It often compounds upon itself, so delays in reducing emissions of fossil fuels are shortening the amount of time remaining to eliminate the use of fossil fuels to preserve a livable planet. Nationalism often impedes solutions to this problem (among many others), as nations place their singular needs above the common good. Our initial proposal got around, and abstracts on many subjects arrived. Within a few weeks, we had enough good material for a 100,000-word book. The book then fattened to two moderate volumes and then to four two very hefty tomes. We tried several different titles as good submissions swelled. We also discovered that our best contributors were experts in their fields, which ranged the world. We settled on three stand-alone books:” 1/ nationalism and racial justice. Our first volume grew as the growth of Black Lives Matter following the brutal killing of George Floyd ignited protests over police brutality and other issues during 2020, following the police assassination of Floyd in Minneapolis. It is estimated that more people took part in protests of police brutality during the summer of 2020 than any other series of marches in United States history. This includes upheavals during the 1960s over racial issues and against the war in Southeast Asia (notably Vietnam). We choose a volume on racism because it is one of nationalism’s main motive forces. This volume provides a worldwide array of work on nationalism’s growth in various countries, usually by authors residing in them, or in the United States with ethnic ties to the nation being examined, often recent immigrants to the United States from them. Our roster of contributors comprises a small United Nations of insightful, well-written research and commentary from Indonesia, New Zealand, Australia, China, India, South Africa, France, Portugal, Estonia, Hungary, Russia, Poland, Kazakhstan, Georgia, and the United States. Volume 2 (this one) describes and analyzes nationalism, by country, around the world, except for the United States; and 3/material directly related to President Donald Trump, and the United States. The first volume is under consideration at the Texas A & M University Press. The other two are under contract to Nova Science Publishers (which includes social sciences). These three volumes may be used individually or as a set. Environmental material is taken up in appropriate places in each of the three books. * * * * * What became the United States of America has been strongly nationalist since the English of present-day Massachusetts and Jamestown first hit North America’s eastern shores. The country propelled itself across North America with the self-serving ideology of “manifest destiny” for four centuries before Donald Trump came along. Anyone who believes that a Trumpian affection for deportation of “illegals” is a new thing ought to take a look at immigration and deportation statistics in Adam Goodman’s The Deportation Machine: America’s Long History of Deporting Immigrants (Princeton University Press, 2020). Between 1920 and 2018, the United States deported 56.3 million people, compared with 51.7 million who were granted legal immigration status during the same dates. Nearly nine of ten deportees were Mexican (Nolan, 2020, 83). This kind of nationalism, has become an assassin of democracy as well as an impediment to solving global problems. Paul Krugman wrote in the New York Times (2019:A-25): that “In their 2018 book, How Democracies Die, the political scientists Steven Levitsky and Daniel Ziblatt documented how this process has played out in many countries, from Vladimir Putin’s Russia, to Recep Erdogan’s Turkey, to Viktor Orban’s Hungary. Add to these India’s Narendra Modi, China’s Xi Jinping, and the United States’ Donald Trump, among others. Bit by bit, the guardrails of democracy have been torn down, as institutions meant to serve the public became tools of ruling parties and self-serving ideologies, weaponized to punish and intimidate opposition parties’ opponents. On paper, these countries are still democracies; in practice, they have become one-party regimes….And it’s happening here [the United States] as we speak. If you are not worried about the future of American democracy, you aren’t paying attention” (Krugmam, 2019, A-25). We are reminded continuously that the late Carl Sagan, one of our most insightful scientific public intellectuals, had an interesting theory about highly developed civilizations. Given the number of stars and planets that must exist in the vast reaches of the universe, he said, there must be other highly developed and organized forms of life. Distance may keep us from making physical contact, but Sagan said that another reason we may never be on speaking terms with another intelligent race is (judging from our own example) could be their penchant for destroying themselves in relatively short order after reaching technological complexity. This book’s chapters, introduction, and conclusion examine the worldwide rise of partisan nationalism and the damage it has wrought on the worldwide pursuit of solutions for issues requiring worldwide scope, such scientific co-operation public health and others, mixing analysis of both. We use both historical description and analysis. This analysis concludes with a description of why we must avoid the isolating nature of nationalism that isolates people and encourages separation if we are to deal with issues of world-wide concern, and to maintain a sustainable, survivable Earth, placing the dominant political movement of our time against the Earth’s existential crises. Our contributors, all experts in their fields, each have assumed responsibility for a country, or two if they are related. This work entwines themes of worldwide concern with the political growth of nationalism because leaders with such a worldview are disinclined to co-operate internationally at a time when nations must find ways to solve common problems, such as the climate crisis. Inability to cooperate at this stage may doom everyone, eventually, to an overheated, stormy future plagued by droughts and deluges portending shortages of food and other essential commodities, meanwhile destroying large coastal urban areas because of rising sea levels. Future historians may look back at our time and wonder why as well as how our world succumbed to isolating nationalism at a time when time was so short for cooperative intervention which is crucial for survival of a sustainable earth. Pride in language and culture is salubrious to individuals’ sense of history and identity. Excess nationalism that prevents international co-operation on harmful worldwide maladies is quite another. As Pope Francis has pointed out: For all of our connectivity due to expansion of social media, ability to communicate can breed contempt as well as mutual trust. “For all our hyper-connectivity,” said Francis, “We witnessed a fragmentation that made it more difficult to resolve problems that affect us all” (Horowitz, 2020, A-12). The pope’s encyclical, titled “Brothers All,” also said: “The forces of myopic, extremist, resentful, and aggressive nationalism are on the rise.” The pope’s document also advocates support for migrants, as well as resistance to nationalist and tribal populism. Francis broadened his critique to the role of market capitalism, as well as nationalism has failed the peoples of the world when they need co-operation and solidarity in the face of the world-wide corona virus pandemic. Humankind needs to unite into “a new sense of the human family [Fratelli Tutti, “Brothers All”], that rejects war at all costs” (Pope, 2020, 6-A). Our journey takes us first to Russia, with the able eye and honed expertise of Richard D. Anderson, Jr. who teaches as UCLA and publishes on the subject of his chapter: “Putin, Russian identity, and Russia’s conduct at home and abroad.” Readers should find Dr. Anderson’s analysis fascinating because Vladimir Putin, the singular leader of Russian foreign and domestic policy these days (and perhaps for the rest of his life, given how malleable Russia’s Constitution has become) may be a short man physically, but has high ambitions. One of these involves restoring the old Russian (and Soviet) empire, which would involve re-subjugating a number of nations that broke off as the old order dissolved about 30 years ago. President (shall we say czar?) Putin also has international ambitions, notably by destabilizing the United States, where election meddling has become a specialty. The sight of Putin and U.S. president Donald Trump, two very rich men (Putin $70-$200 billion; Trump $2.5 billion), nuzzling in friendship would probably set Thomas Jefferson and Vladimir Lenin spinning in their graves. The road of history can take some unanticipated twists and turns. Consider Poland, from which we have an expert native analysis in chapter 2, Bartosz Hlebowicz, who is a Polish anthropologist and journalist. His piece is titled “Lawless and Unjust: How to Quickly Make Your Own Country a Puppet State Run by a Group of Hoodlums – the Hopeless Case of Poland (2015–2020).” When I visited Poland to teach and lecture twice between 2006 and 2008, most people seemed to be walking on air induced by freedom to conduct their own affairs to an unusual degree for a state usually squeezed between nationalists in Germany and Russia. What did the Poles then do in a couple of decades? Read Hlebowicz’ chapter and decide. It certainly isn’t soft-bellied liberalism. In Chapter 3, with Bruce E. Johansen, we visit China’s western provinces, the lands of Tibet as well as the Uighurs and other Muslims in the Xinjiang region, who would most assuredly resent being characterized as being possessed by the Chinese of the Han to the east. As a student of Native American history, I had never before thought of the Tibetans and Uighurs as Native peoples struggling against the Independence-minded peoples of a land that is called an adjunct of China on most of our maps. The random act of sitting next to a young woman on an Air India flight out of Hyderabad, bound for New Delhi taught me that the Tibetans had something to share with the Lakota, the Iroquois, and hundreds of other Native American states and nations in North America. Active resistance to Chinese rule lasted into the mid-nineteenth century, and continues today in a subversive manner, even in song, as I learned in 2018 when I acted as a foreign adjudicator on a Ph.D. dissertation by a Tibetan student at the University of Madras (in what is now in a city called Chennai), in southwestern India on resistance in song during Tibet’s recent history. Tibet is one of very few places on Earth where a young dissident can get shot to death for singing a song that troubles China’s Quest for Lebensraum. The situation in Xinjiang region, where close to a million Muslims have been interned in “reeducation” camps surrounded with brick walls and barbed wire. They sing, too. Come with us and hear the music. Back to Europe now, in Chapter 4, to Portugal and Spain, we find a break in the general pattern of nationalism. Portugal has been more progressive governmentally than most. Spain varies from a liberal majority to military coups, a pattern which has been exported to Latin America. A situation such as this can make use of the term “populism” problematic, because general usage in our time usually ties the word into a right-wing connotative straightjacket. “Populism” can be used to describe progressive (left-wing) insurgencies as well. José Pinto, who is native to Portugal and also researches and writes in Spanish as well as English, in “Populism in Portugal and Spain: a Real Neighbourhood?” provides insight into these historical paradoxes. Hungary shares some historical inclinations with Poland (above). Both emerged from Soviet dominance in an air of developing freedom and multicultural diversity after the Berlin Wall fell and the Soviet Union collapsed. Then, gradually at first, right wing-forces began to tighten up, stripping structures supporting popular freedom, from the courts, mass media, and other institutions. In Chapter 5, Bernard Tamas, in “From Youth Movement to Right-Liberal Wing Authoritarianism: The Rise of Fidesz and the Decline of Hungarian Democracy” puts the renewed growth of political and social repression into a context of worldwide nationalism. Tamas, an associate professor of political science at Valdosta State University, has been a postdoctoral fellow at Harvard University and a Fulbright scholar at the Central European University in Budapest, Hungary. His books include From Dissident to Party Politics: The Struggle for Democracy in Post-Communist Hungary (2007). Bear in mind that not everyone shares Orbán’s vision of what will make this nation great, again. On graffiti-covered walls in Budapest, Runes (traditional Hungarian script) has been found that read “Orbán is a motherfucker” (Mikanowski, 2019, 58). Also in Europe, in Chapter 6, Professor Ronan Le Coadic, of the University of Rennes, Rennes, France, in “Is There a Revival of French Nationalism?” Stating this title in the form of a question is quite appropriate because France’s nationalistic shift has built and ebbed several times during the last few decades. For a time after 2000, it came close to assuming the role of a substantial minority, only to ebb after that. In 2017, the candidate of the National Front reached the second round of the French presidential election. This was the second time this nationalist party reached the second round of the presidential election in the history of the Fifth Republic. In 2002, however, Jean-Marie Le Pen had only obtained 17.79% of the votes, while fifteen years later his daughter, Marine Le Pen, almost doubled her father's record, reaching 33.90% of the votes cast. Moreover, in the 2019 European elections, re-named Rassemblement National obtained the largest number of votes of all French political formations and can therefore boast of being "the leading party in France.” The brutality of oppressive nationalism may be expressed in personal relationships, such as child abuse. While Indonesia and Aotearoa [the Maoris’ name for New Zealand] hold very different ranks in the United Nations Human Development Programme assessments, where Indonesia is classified as a medium development country and Aotearoa New Zealand as a very high development country. In Chapter 7, “Domestic Violence Against Women in Indonesia and Aotearoa New Zealand: Making Sense of Differences and Similarities” co-authors, in Chapter 8, Mandy Morgan and Dr. Elli N. Hayati, from New Zealand and Indonesia respectively, found that despite their socio-economic differences, one in three women in each country experience physical or sexual intimate partner violence over their lifetime. In this chapter ther authors aim to deepen understandings of domestic violence through discussion of the socio-economic and demographic characteristics of theit countries to address domestic violence alongside studies of women’s attitudes to gender norms and experiences of intimate partner violence. One of the most surprising and upsetting scholarly journeys that a North American student may take involves Adolf Hitler’s comments on oppression of American Indians and Blacks as he imagined the construction of the Nazi state, a genesis of nationalism that is all but unknown in the United States of America, traced in this volume (Chapter 8) by co-editor Johansen. Beginning in Mein Kampf, during the 1920s, Hitler explicitly used the westward expansion of the United States across North America as a model and justification for Nazi conquest and anticipated colonization by Germans of what the Nazis called the “wild East” – the Slavic nations of Poland, the Baltic states, Ukraine, and Russia, most of which were under control of the Soviet Union. The Volga River (in Russia) was styled by Hitler as the Germans’ Mississippi, and covered wagons were readied for the German “manifest destiny” of imprisoning, eradicating, and replacing peoples the Nazis deemed inferior, all with direct references to events in North America during the previous century. At the same time, with no sense of contradiction, the Nazis partook of a long-standing German romanticism of Native Americans. One of Goebbels’ less propitious schemes was to confer honorary Aryan status on Native American tribes, in the hope that they would rise up against their oppressors. U.S. racial attitudes were “evidence [to the Nazis] that America was evolving in the right direction, despite its specious rhetoric about equality.” Ming Xie, originally from Beijing, in the People’s Republic of China, in Chapter 9, “News Coverage and Public Perceptions of the Social Credit System in China,” writes that The State Council of China in 2014 announced “that a nationwide social credit system would be established” in China. “Under this system, individuals, private companies, social organizations, and governmental agencies are assigned a score which will be calculated based on their trustworthiness and daily actions such as transaction history, professional conduct, obedience to law, corruption, tax evasion, and academic plagiarism.” The “nationalism” in this case is that of the state over the individual. China has 1.4 billion people; this system takes their measure for the purpose of state control. Once fully operational, control will be more subtle. People who are subject to it, through modern technology (most often smart phones) will prompt many people to self-censor. Orwell, modernized, might write: “Your smart phone is watching you.” Ming Xie holds two Ph.Ds, one in Public Administration from University of Nebraska at Omaha and another in Cultural Anthropology from the Chinese Academy of Social Sciences, Beijing, where she also worked for more than 10 years at a national think tank in the same institution. While there she summarized news from non-Chinese sources for senior members of the Chinese Communist Party. Ming is presently an assistant professor at the Department of Political Science and Criminal Justice, West Texas A&M University. In Chapter 10, analyzing native peoples and nationhood, Barbara Alice Mann, Professor of Honours at the University of Toledo, in “Divide, et Impera: The Self-Genocide Game” details ways in which European-American invaders deprive the conquered of their sense of nationhood as part of a subjugation system that amounts to genocide, rubbing out their languages and cultures -- and ultimately forcing the native peoples to assimilate on their own, for survival in a culture that is foreign to them. Mann is one of Native American Studies’ most acute critics of conquests’ contradictions, and an author who retrieves Native history with a powerful sense of voice and purpose, having authored roughly a dozen books and numerous book chapters, among many other works, who has traveled around the world lecturing and publishing on many subjects. Nalanda Roy and S. Mae Pedron in Chapter 11, “Understanding the Face of Humanity: The Rohingya Genocide.” describe one of the largest forced migrations in the history of the human race, the removal of 700,000 to 800,000 Muslims from Buddhist Myanmar to Bangladesh, which itself is already one of the most crowded and impoverished nations on Earth. With about 150 million people packed into an area the size of Nebraska and Iowa (population less than a tenth that of Bangladesh, a country that is losing land steadily to rising sea levels and erosion of the Ganges river delta. The Rohingyas’ refugee camp has been squeezed onto a gigantic, eroding, muddy slope that contains nearly no vegetation. However, Bangladesh is majority Muslim, so while the Rohingya may starve, they won’t be shot to death by marauding armies. Both authors of this exquisite (and excruciating) account teach at Georgia Southern University in Savannah, Georgia, Roy as an associate professor of International Studies and Asian politics, and Pedron as a graduate student; Roy originally hails from very eastern India, close to both Myanmar and Bangladesh, so he has special insight into the context of one of the most brutal genocides of our time, or any other. This is our case describing the problems that nationalism has and will pose for the sustainability of the Earth as our little blue-and-green orb becomes more crowded over time. The old ways, in which national arguments often end in devastating wars, are obsolete, given that the Earth and all the people, plants, and other animals that it sustains are faced with the existential threat of a climate crisis that within two centuries, more or less, will flood large parts of coastal cities, and endanger many species of plants and animals. To survive, we must listen to the Earth, and observe her travails, because they are increasingly our own.

Abstract Citrate transporters belonging to the multidrug and toxic compound extrusion (MATE) family of membrane transporters in sorghum and maize, SbMATE and ZmMATE1, respectively, play a major role in aluminium (Al) tolerance. However, these MATE members show regulatory differences, as well as peculiarities in their genetic effect and mode of action. These aspects, which are discussed in this chapter, have to be considered to design successful breeding programmes in order to achieve maximum Al tolerance and, consequently, to improve grain and biomass production in regions of the world with Al toxicity. As shown in this chapter, target genes with major effects and molecular tools are available for marker-assisted breeding for improving Al tolerance both in sorghum and maize. However, wide adaptation to acid soils should be sought by pyramiding genes controlling different traits such as drought tolerance, P acquisition, resistance to diseases and other stresses commonly found in each agroecological environment.

AbstractExtreme climate change events such as frequent and prolonged droughts or floods associated with climate change can be very disruptive to peoples’ livelihoods particularly in rural settings, where people rely on the immediate environment for livelihood. Shocks in the people’s livelihoods can trigger diverse responses that include migration as a coping or adaption strategy. Migration takes many forms depending on the context and resources availability. Very few studies in Kenya have used qualitative analysis to bring up women’s voices in relation to gender, climate change, and migration, especially along hydrological gradient. This chapter presents results of qualitative research conducted from 58 participants in 2018 in three counties in Kenya, namely, Kiambu County, Machakos, and Makueni. The study sought to examine gender perceptions related to climate-induced migration, that is: whether climate change is perceived to be affecting women’s livelihood differently from that of men; examine in what ways experiences of climate induced migration differed for men and women; explore perceptions on the county government efforts to cope with climate-induced migration; and examine perceptions of the role of nongovernmental agencies in helping citizens cope with climate change. From the results obtained on ways in which climate change affected women livelihoods more than men had four themes: (1) women exerted more strain in domestic chores, child/family care, and in the farm labor; (2) women also experienced more time demands. The sources of water and firewood were getting more scarce leading to women travel long distances in search to fetch water and firewood; (3) reduced farm yields, hence inadequate food supply; and (4) the effects of time and strain demands on women was a contributory factor to women poor health and domestic conflicts. Several measures that the county government could take to assist women to cope with climate change-induced migration had five themes which include the following: (1) developing climate change mitigations, and reducing deforestation; (2) increasing water harvesting and storage; (3) develop smart agriculture through the use of drought-resistant crops and drought mitigation education; (4) encourage diversification of livelihoods; and finally (5) providing humanitarian assistance to the most vulnerable populations such as orphans and the very poor. Thirdly, the measures mentioned that NGO’s could take to assist rural communities to cope with climate change-induced migration did not vary significantly from those mentioned for county government, except probably for a new theme of increasing advocacy for climate adaption policies.

AbstractExtreme climate change events such as frequent and prolonged droughts or floods associated with climate change can be very disruptive to peoples’ livelihoods particularly in rural settings, where people rely on the immediate environment for livelihood. Shocks in the people’s livelihoods can trigger diverse responses that include migration as a coping or adaption strategy. Migration takes many forms depending on the context and resources availability. Very few studies in Kenya have used qualitative analysis to bring up women’s voices in relation to gender, climate change, and migration, especially along hydrological gradient. This chapter presents results of qualitative research conducted from 58 participants in 2018 in three counties in Kenya, namely, Kiambu County, Machakos, and Makueni. The study sought to examine gender perceptions related to climate-induced migration, that is: whether climate change is perceived to be affecting women’s livelihood differently from that of men; examine in what ways experiences of climate induced migration differed for men and women; explore perceptions on the county government efforts to cope with climate-induced migration; and examine perceptions of the role of nongovernmental agencies in helping citizens cope with climate change. From the results obtained on ways in which climate change affected women livelihoods more than men had four themes: (1) women exerted more strain in domestic chores, child/family care, and in the farm labor; (2) women also experienced more time demands. The sources of water and firewood were getting more scarce leading to women travel long distances in search to fetch water and firewood; (3) reduced farm yields, hence inadequate food supply; and (4) the effects of time and strain demands on women was a contributory factor to women poor health and domestic conflicts. Several measures that the county government could take to assist women to cope with climate change-induced migration had five themes which include the following: (1) developing climate change mitigations, and reducing deforestation; (2) increasing water harvesting and storage; (3) develop smart agriculture through the use of drought-resistant crops and drought mitigation education; (4) encourage diversification of livelihoods; and finally (5) providing humanitarian assistance to the most vulnerable populations such as orphans and the very poor. Thirdly, the measures mentioned that NGO’s could take to assist rural communities to cope with climate change-induced migration did not vary significantly from those mentioned for county government, except probably for a new theme of increasing advocacy for climate adaption policies.

AbstractAgriculture is the art and science of food production which spans soil cultivation, crop growing, and livestock rearing. Over the years, it has served as a means of employment and accounts for more than one-third of total gross domestic product. Cereals, which include rice, maize, and sorghum, are the major dietary energy suppliers and they provide significant amounts of protein, minerals (potassium and calcium), and vitamins (vitamin A and C). The growth and good yield of cereal crop can be greatly influenced by elements of weather and climate such as temperature, sunlight, and relative humidity. While climate determines the choice of what plant to cultivate and how to cultivate, it has been undoubtedly identified as one of the fundamental factors that determine both crop cultivation and livestock keeping. The chapter, though theoretical, adopted Kwara State, Nigeria, as the focus due to favorable weather conditions that support grains production. It was observed that the effect of climate change on cereal production includes: drastic reduction in grains production, reduction in farmers’ profit level, increment in cost during production, diversification to nonfarming activities, and discouragement of youth from participating in agricultural activities. Also, the adopted coping strategies employed by farmers in the focus site were early planting, planting of improved variety, irrigation activities, alternates crop rotation, and cultivation of more agricultural areas. The chapter thus concluded that climate change has negative impact on cereals production and recommends that government should provide communal irrigation facilities that will cushion the effect of low rains on farmers’ productivity, while early planting and cultivation of drought-resistant cultivars should be encouraged.

From space, much of Indonesia appeared to be on fire. One of the strongest El Niño/Southern Oscillation (ENSO) events of the twentieth century had generated drought conditions in the fall of 1997 and early 1998. These conditions, probably in concert with the impacts of logging, resulted in what has been called the largest fire disaster ever observed (Siegert et al. 2001). The powerful 1997–8 ENSO also led to extensive fires in Amazonia. The humid tropics, home to Earth’s greatest concentrations of biodiversity, had long been thought to be fire resistant due to high-moisture levels in the leaf litter and the humidity of the understory. The massive fires of 1997–8 increased our understanding of the complex interactions between fire and humid tropical forests. Since the late 1990s, a new synthesis has emerged linking ENSO events, drought, logging, and fire in the wet tropics. This synthesis has sought to understand the impacts of these phenomena on tropical environments and also explain the role humans play in tropical fires and fire impacts. Remote sensing has been an important tool in forging this new synthesis of understanding. For example, NOAA’s workhorse AVHRR sensor, the SeaWiFS sensor, and NASA’s TOMS instrument were among the satellite tools available to provide imagery of the dramatic events of 1997–8. In this chapter, we discuss the potential for remote sensing to detect, monitor, and increase our understanding of certain disturbance mechanisms affecting ecosystems. We focus on fires and floods, adding shorter sections at the end on two other drivers of disturbance, volcanoes and dams. A key challenge lies in understanding the degree to which logging, even selective logging, is interacting with periodic droughts to drive fires in humid forests. Are humid tropical forests essentially immune to fire unless disturbed by human logging, or have they always been subject to climate-induced droughts and subsequent fires? The answer is crucial in determining our impact on these great storehouses of biodiversity and holds major implications for forest management. Part of the answer lies in looking backward in time.

The common wheat genotypes under study showed a differentiated variability in terms of suscep-tibility to septoria, brown rust, spike fusariosis, which made it possible to differentiate them into clusters and identify those with higher resistance to these diseases. Based on the assessments from 2020-2021, the varieties Trubion, Numitor, Urbanus, Python, Miranda, Centurion, Amor, Aneta, Neven, Messino, Nasnaga, Tika-Taka, Judița, Avenue, Speranța, Dacia, Transilvania, Selania, Avânt which have shown resistance to extreme drought, fungal diseases and high indices of the spike productivity elements can be recommended as the initial material for the breeding programs.

Drought stress is a major limitation to bread wheat (Triticumaestivum L.) productivity and its yield stability in arid and semi-arid regions of world including parts of Israel and the U.S. Currently, breeding for sustained yields under drought stress is totally dependent on the use of yield and several key physiological attributes as selection indices. The attempt to identify the optimal genotype by evaluating the phenotype is undermining progress in such breeding programs. Osmotic adjustment (OA) is an effective drought resistance mechanism in many crop plants. Evidence exists that there is a genetic variation for OA in wheat and that high OA capacity supports wheat yields under drought stress. The major objective of this research was to identify molecular markers (RFLPs, restriction fragment length polymorphisms; and AFLPs, amplified fragment length polymorph isms) linked to OA as a major attribute of drought resistance in wheat and thus to facilitate marker-assisted selection for drought resistance. We identified high and low OA lines of wheat and from their cross developed recombinant inbred lines (RILs) used in the molecular tagging of OA in relation to drought resistance in terms of plant production under stress. The significant positive co-segregation of OA, plant water status and yield under stress in this RIL population provided strong support for the important role of OA as a drought resistance mechanism sustaining wheat production under drought stress. This evidence was obtained in addition to the initial study of parental materials for constructing this RIL population, which also gave evidence for a strong correlation between OA and grain yield under stress. This research therefore provides conclusive evidence on the important role of OA in sustaining wheat yield under drought stress. The measurement of OA is difficult and the selection for drought resistance by the phenotypic expression of OA is practically impossible. This research provided information on the genetic basis of OA in wheat in relations to yield under stress. It provided the basic information to indicate that molecular marker assisted selection for OA in wheat is possible. The RIL population has been created by a cross between two agronomic spring wheat lines and the high OA recombinants in this population presented very high OA values, not commonly observed in wheat. These recombinants are therefore an immediate valuable genetic recourse for breeding well-adapted drought resistant wheat in Texas and Israel. We feel that this work taken as a whole eliminate the few previous speculated . doubts about the practical role of OA as an important mechanism of drought resistance in economic crop plants. As such it should open the way, in terms of both concept and the use of marker assisted selection, for improving drought resistance in wheat by deploying high osmotic adjustment.

Research problem: Bread wheat (Triticumaestivum) provides approximately 20% of the calories and proteins consumed by humankind. As the world population continues to increase, it is necessary to improve wheat yields, increase grain quality, and minimize the losses produced by biotic and abiotic stresses. Stripe rust, caused by Pucciniastriiformisf. sp. tritici(Pst), is one of the most destructive diseases of wheat. The new pathogen races are more virulent and aggressive than previous ones and have produced large economic losses. A rich source for stripe-rust resistance genes (Yr) was found in wild emmer wheat populations from Israel. Original Project goals: Our long term goal is to identify, map, clone, characterize and deploy in breeding, novel wild emmer Yr genes, and combine them with multiple beneficial traits. The current study was aiming to map and clone YrG303 and Yr15, located on chromosome 1BS and combine them with drought resistance and grain quality genes. Positional cloning of YrG303/Yr15: Fine mapping of these genes revealed that YrG303 is actually allelic to Yr15. Fine genetic mapping using large segregating populations resulted in reduction of the genetic interval spanning Yr15 to less than 0.1 cM. Physical mapping of the YrG303/Yr15 locus was based on the complete chromosome 1BS physical map of wheat constructed by our group. Screening of 1BS BAC library with Yr15 markers revealed a long BAC scaffold covering the target region. The screening of T. dicoccoidesaccession-specific BAC library with Yr15 markers resulted in direct landing on the target site. Sequencing of T. dicoccoidesBAC clones that cover the YrG303/Yr15 locus revealed a single candidate gene (CG) with conserved domains that may indicate a role in disease resistance response. Validation of the CG was carried out using EMS mutagenesis (loss-of- function approach). Sequencing of the CG in susceptible yr15/yrG303 plants revealed three independent mutants that harbour non-functional yr15/yrG303 alleles within the CG conserved domains, and therefore validated its function as a Pstresistance gene. Evaluation of marker-assisted-selection (MAS) for Yr15. Introgressions of Yr15 into cultivated wheat are widely used now. Recently, we have shown that DNA markers linked to Yr15 can be used as efficient tools for introgression of Yr15 into cultivated wheat via MAS. The developed markers were consistent and polymorphic in all 34 tested introgressions and are the most recommended markers for the introgression of Yr15. These markers will facilitate simultaneous selection for multiple Yr genes and help to avoid escapees during the selection process. Engineering of improved chromosome 1BS that harbors multiple beneficial traits. We have implemented the knowledge and genetic resources accumulated in this project for the engineering of 1B "super-chromosome" that harbors multiple beneficial traits. We completed the generation of a chromosome including the rye 1RS distal segment associated with improved drought tolerance with the Yr gene, Yr15, and the strong gluten allele 7Bx-over-expressor (7Bxᴼᴱ). We have completed the introgression of this improved chromosome into our recently released variety Patwin-515HP and our rain fed variety Kern, as well as to our top breeding lines UC1767 and UC1745. Elucidating the mechanism of resistance exhibited by Yr36 (WKS1). The WHEAT KINASE START1 (WKS1) resistance gene (Yr36) confers partial resistance to Pst. We have shown that wheat plants transformed with WKS1 transcript are resistant to Pst. WKS1 is targeted to the chloroplast where it phosphorylates the thylakoid-associatedascorbateperoxidase (tAPX) and reduces its ability to detoxify peroxides. Based on these results, we propose that the phosphorylation of tAPX by WKS1 reduces the ability of the cells to detoxify ROS and contributes to cell death. Distribution and diversity of WKS in wild emmer populations. We have shown that WKS1 is present only in the southern distribution range of wild emmer in the Fertile Crescent. Sequence analysis revealed a high level of WKS1 conservation among wild emmer populations, in contrast to the high level of diversity observed in NB-LRR genes. This phenomenon shed some light on the evolution of genes that confer partial resistance to Pst. Three new WKS1 haplotypes displayed a resistance response, suggesting that they can be useful to improve wheat resistance to Pst. In summary, we have improved our understanding of cereals’ resistance mechanisms to rusts and we have used that knowledge to develop improved wheat varieties.

PGPR bacteria include taxonomically diverse bacterial species that function for improving plant mineral nutrition, stress tolerance, and disease suppression. A number of PGPR are being developed and commercialized as soil and seed inoculants, but to date, their interactions with resident bacterial populations are still poorly understood, and-almost nothing is known about the effects of soil management practices on their population size and activities. To this end, the original objectives of this research project were: 1) To examine microbial community interactions with plant-growth-promoting rhizobacteria (PGPR) and their plant hosts. 2) To explore the factors that affect PGPR population size and activity on plant root surfaces. In our original proposal, we initially prqposed the use oflow-resolution methods mainly involving the use of PCR-DGGE and PLFA profiles of community structure. However, early in the project we recognized that the methods for studying soil microbial communities were undergoing an exponential leap forward to much more high resolution methods using high-throughput sequencing. The application of these methods for studies on rhizosphere ecology thus became a central theme in these research project. Other related research by the US team focused on identifying PGPR bacterial strains and examining their effective population si~es that are required to enhance plant growth and on developing a simulation model that examines the process of root colonization. As summarized in the following report, we characterized the rhizosphere microbiome of four host plant species to determine the impact of the host (host signature effect) on resident versus active communities. Results of our studies showed a distinct plant host specific signature among wheat, maize, tomato and cucumber, based on the following three parameters: (I) each plant promoted the activity of a unique suite of soil bacterial populations; (2) significant variations were observed in the number and the degree of dominance of active populations; and (3)the level of contribution of active (rRNA-based) populations to the resident (DNA-based) community profiles. In the rhizoplane of all four plants a significant reduction of diversity was observed, relative to the bulk soil. Moreover, an increase in DNA-RNA correspondence indicated higher representation of active bacterial populations in the residing rhizoplane community. This research demonstrates that the host plant determines the bacterial community composition in its immediate vicinity, especially with respect to the active populations. Based on the studies from the US team, we suggest that the effective population size PGPR should be maintained at approximately 105 cells per gram of rhizosphere soil in the zone of elongation to obtain plant growth promotion effects, but emphasize that it is critical to also consider differences in the activity based on DNA-RNA correspondence. The results ofthis research provide fundamental new insight into the composition ofthe bacterial communities associated with plant roots, and the factors that affect their abundance and activity on root surfaces. Virtually all PGPR are multifunctional and may be expected to have diverse levels of activity with respect to production of plant growth hormones (regulation of root growth and architecture), suppression of stress ethylene (increased tolerance to drought and salinity), production of siderophores and antibiotics (disease suppression), and solubilization of phosphorus. The application of transcriptome methods pioneered in our research will ultimately lead to better understanding of how management practices such as use of compost and soil inoculants can be used to improve plant yields, stress tolerance, and disease resistance. As we look to the future, the use of metagenomic techniques combined with quantitative methods including microarrays, and quantitative peR methods that target specific genes should allow us to better classify, monitor, and manage the plant rhizosphere to improve crop yields in agricultural ecosystems. In addition, expression of several genes in rhizospheres of both cucumber and whet roots were identified, including mostly housekeeping genes. Denitrification, chemotaxis and motility genes were preferentially expressed in wheat while in cucumber roots bacterial genes involved in catalase, a large set of polysaccharide degradation and assimilatory sulfate reduction genes were preferentially expressed.

The overall objective of this research was to elucidate the horticultural, pathological, physiological and molecular factors impacting melon varieties (scion) grafted onto M. cannonballus resistant melon and squash rootstocks. Specific objectives were- to compare the performance of resistant melon germplasm (grafted and non-grafted) when exposed to M. cannoballus in the Lower Rio Grande valley and the Wintergarden, Texas, and in the Arava valley, Israel; to address inter-species relationships between a Monosporascus resistant melon rootstock and susceptible melon scions in terms of fruit-set, fruit quality and yield; to study the factors which determine the compatibility between the rootstock and the scion in melon; to compare the responses of graft unions of differing compatibilities under disease stress, high temperatures, deficit irrigation, and salinity stress; and to investigate the effect of rootstock on stress related gene expression in the scion. Some revisions were- to include watermelon in the Texas investigations since it is much more economically important to the state, and also to evaluate additional vine decline pathogens Didymella bryoniae and Macrophomina phaseolina. Current strategies for managing vine decline rely heavily on soil fumigation with methyl bromide, but restrictions on its use have increased the need for alternative management strategies. Grafting of commercial melon varieties onto resistant rootstocks with vigorous root systems is an alternative to methyl bromide for Monosporascus root rot/vine decline (MRR/VD) management in melon production. Extensive selection and breeding has already produced potential melon rootstock lines with vigorous root systems and disease resistance. Melons can also be grafted onto Cucurbita spp., providing nonspecific but efficient protection from a wide range of soil-borne diseases and against some abiotic stresses, but compatibility between the scion and the rootstock can be problematic. During the first year experiments to evaluate resistance to the vine decline pathogens Monosporascus cannonballus, Didymella bryoniae, and Macrophomina phaseolina in melon and squash rootstocks proved the efficacy of these grafted plants in improving yield and quality. Sugars and fruit size were better in grafted versus non-grafted plants in both Texas and Israel. Two melons (1207 and 124104) and one pumpkin, Tetsukabuto, were identified as the best candidate rootstocks in Texas field trials, while in Israel, the pumpkin rootstock RS59 performed best. Additionally, three hybrid melon rootstocks demonstrated excellent resistance to both M. cannonballus and D. bryoniae in inoculated tests, suggesting that further screening for fruit quality and yield should be conducted. Experiments with ABA in Uvalde demonstrated a significant increase in drought stress tolerance and concurrent reduction in transplant shock due to reduced transpiration for ‘Caravelle’ plants. In Israel, auxin was implicated in reducing root development and contributing to increased hydrogen peroxide, which may explain incompatibility reactions with some squash rootstocks. However, trellised plants responded favorably to auxin (NAA) application at the time of fruit development. Gene expression analyses in Israel identified several cDNAs which may code for phloem related proteins, cyclins or other factors which impact the graft compatibility. Manipulation of these genes by transformation or traditional breeding may lead to improved rootstock cultivars. Commercial applications of the new melon rootstocks as well as the ABA and TIBA growth regulators have potential to improve the success of grafted melons in both Israel and Texas. The disease resistance, fruit quality and yield data generated by the field trials will help producers in both locations to decide what rootstock/scion combinations will be best.