## 2 Enhancing Food Production through RS Applications in Agriculture
### Monitoring Agricultural Crop Status  
Crop status encompasses growth, health and seasonal progress. Abiotic factors (e.g., nutrients, irradiation, temperature and water) and biotic factors (e.g., diseases, pests and weeds) can have a significant impact on crop status [74]. Information on crop growth conditions has been identified as an essential indicator for yield forecasting and food security assessment [75]. A wide range of commercial crops might be affected by plant diseases and pests, which can pose major risks to final crop yields. Based on recent estimates, annually around 20-40% of global crop production is lost to pests, and plant diseases and invasive insects are responsible for global economic losses of around USD 220 billion and USD 70 billion, respectively [76]. In their technical report, [PERSON] and [PERSON] [77] indicated that as a result of climate change, around 16 of the most important crops grown in the Sahel are affected by 100 diseases. Among the 34 photoplasmas (microorganisms) ribosomal groups reported globally, 14 were reported in Middle Eastern countries [78]. In addition, aggressive strains of fungal disease such as wheat rusts have been detected in East Africa and the Middle East, and they can cause devastating losses to wheat crops [79]. According to the USDA report, in 2010-2011, yellow rust outbreaks reduced wheat production to 35% below record levels in Syria and 5% in Turkey compared to the previous year [80]. In Africa, maize yield was reported to have decreased by between 30% and 60% due to grey leaf spot (GLS) [81]. Furthermore, poor crop protection practices in these regions might have contributed to the impact of pests and diseases on crop yield. For example, due to pest attack, losses in rice of up to 51% were recorded in West Africa, and of 22% in Oceania [82]. Lastly, due to its rapid spread and significant impact on crop yield loss, there exists global concern about fall armyworm. [PERSON] [83] indicated that fall armyworm is spreading rapidly in Africa, the Near East and Asia. It has been predicted that in the major maize-producing countries in SSA, annual yield losses attributable to FAW are between USD 2.5 and 6.2 billion [84]. Despite these losses, insufficient knowledge regarding the probability of occurrence, direction and distribution of pests and diseases, as well as the severity of their impact on crops, has posed further challenges to control such issues. Therefore, an efficient monitoring system is needed to provide cost-effective solutions in these poor regions. In terms of weather-related disasters, drought is one of the key risks to global crop yield. Globally, it is estimated that droughts have caused a 5.1% cereal yield loss during the past four decades [85]. ASA regions are more exposed to the risk of drought and its consequences because they are the most vulnerable regions to climate variability and climate change [86; 15; 87]. At the regional scale, agricultural drought has affected around 810 million ha (27.5% of Africa) and around 452 million ha (33.8% of the total Arab Region) [88]. In addition, the frequency and intensity of extreme weather events such as droughts and floods are projected to increase in the Middle East and North Africa regions due to climate change [89; 90]. The increasing frequency and intensity of extreme weather events have caused extreme declines in crop yields in ASA regions. For example, in Iraq, the drought in 2008-2009 caused a loss of crop production of 51% compared to the previous year. In Turkey, total crop yields declined substantially, costing USD 1-2 billion and with 435,000 farmers affected [91]. [PERSON] et al. [92] found that the average annual production losses across West Africa in 2000-2009 associated with historical climate change, accounted for USD 2.33-4.02 billion for millet and USD 0.73-2.17 billion for sorghum. To mitigate such events, cost-effective real-time monitoring systems should be put in place to warn local authorities.