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This work is licensed under Creative Commons Attribution 4.0 License AJBSR.MS.ID.000681

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Jatropha curcas L. belongs to family Euphorbiaceae, Jatropha curcas is a valuable multi-purpose crop, historically it was used as medicine for wounds and leaves used as drinks against malaria, jatropha plants used to control soil degradation, alleviate erosion, desertification and increase soil fertility, however, in last decades there is more attention to use jatropha oil for produce biodiesel,  Jatropha curcas is easily propagated by seeds or stem cutting, it is tolerant for drought for longtime, it is grow well with treated wastewater, also, it can be grown on marginal land. Jatropha curcas seed have about 32-40% valuable oil used to produce biofuel, therefore, it could be the source for biodiesel production particularly in arid and semiarid regions.

Citrus trees (Citrus spp.) considered one of the major fruit worldwide, due to continuous and excessive use of synthetic fertilizers, there is a severe hazard to human health and to environment. The integrated fertilizing system in citrus orchards contributes to improve crop production through eco-friendly nutrient supply, producing healthy fruits, enhancing the plant tolerance to biotic stresses, increases growers' profits, and sustains natural resources. There are numerous types of organic fertilizers used in citrus orchards include Compost, Vermicompost, Humic substances, Biochar, Farm manure, and, microorganisms in biofertilizers increase the amount and availability of essential elements to plant, there are various biofertilizers used for different purposes according to the role of microorganisms like Nitrogen-fixing microorganisms like Azotobacter, Azospirillum, Rhizobium and Frankia; Phosphorous solubilizing microbes such as Pseudomonas and Bacillus; Phosphorous mobilizing as Vascular arbuscular mycorrhiza, and Plant growth promoting rhizobacteria (PGPR). There are numerous beneficial effects of organic and biofertilizers include increasing availability of nutrients in soils, increase the tree productivity, enhancing fruit quality, improve soil properties, stimulate microflora population in the rhizosphere, reducing the harmful effects of pathogenic organisms, and improving plant tolerance to biotic and abiotic stresses, particularly using both organic and biofertilizers play a critical role in environmental conservation, they can compensate large amounts of inorganic, fertilizer , reducing the great amount of inorganic fertilizer used indiscriminately in citrus orchards. Using a consortium of organic and biofertilizers with mineral fertilizers provide a positive response in citrus orchards.

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Climate change has a dramatic effect on growth and productivity of various crops, there are various environmental elements affect the life cycle of annual and perennial plants, like high temperature, heatwaves, drought, cool temperature and frost, rising carbon dioxide (CO2) levels. Climate change represents a dangerous challenge for mankind, there need for an efficient strategy to guarantee adequate crop production for humanity. Citrus is one of the main fruits all over the world, citrus can be grown in different climatic zones ranging from tropical, subtropical, arid and semi-arid areas, citrus grows properly in the range from 12.8 to 37˚C, which considered the optimum temperature for citrus growth and fruiting, while, sever high temperature (above 44-45˚C) stopped citrus growth completely. Low temperature considered the limiting factor for the geographical distribution of citrus, low temperature could stoop metabolism activity, whereas, chilling and frost cause severe injuries and demolish the whole tree. Temperature fluctuation affects negatively growth, decreases total yield, and reduces fruit quality particularly when occurred during the maturity stage, also, there are negative effects of heatwaves on the production of different citrus varieties particularly seedless varieties like Navel orange, and some Mandarin and lemon cultivars. On another side, rising carbon dioxide has positive effects on the growth of citrus seedlings and trees productivity.