**5. Agronomy and food security**

*Agronomy - Climate Change and Food Security*

is due to improvement in irrigation, fertilizer use, chemical herbicides for weed control and pesticides for pest and disease control, adaptation of new production technology, high-yield varieties, and improvements in crop phenotype from breeding, especially the widespread adoptions of semi-dwarfing genes in cereals [14] has resulted in yield per unit area increase. However, this increase was not similar throughout the world. Yield increase was observed in Europe, America, and Asia, but there was decline in African countries in crop yield due to the unavailability of inputs, credit, high-yielding varieties, and irrigation water and increase in temperature. Gregory et al. [15] concluded that an increase of 1°C in temperature above 32°C can decrease yield of rice by 5%. These temperature effects were the most deleterious for the major crops like wheat, rice, and maize [16–18]. Additionally,

increase in temperature also affects the wheat protein contents [19, 20].

The effect of climate change on productivity of crop shows the major role of agronomists to develop such varieties and cropping system that are more resilient to the climate change with high production. Modification in the crop due to change in climate was not significant, its might be due to gradually increase in carbon di oxide and temperature rate that modified the time of sowing, veracity and crop production management practices will allow some adaptation in the crop production system. These include various adaptations like the selection of crops that have strong mechanisms and high resistance against disease, are more resilient to the abiotic stresses like heat and temperature, and have stronger genetic enhancement to compete with changing environment and the selection of cropping system according to the current climatic condition. According to Tubiello et al. [21], increase in CO2 concentration and temperature can decrease the yield of existing varieties by 10–40%. The combination of early planting of summer and spring crops can sustain the present yield of the crops [21]. Change in climate may cause change in water regimes, which may increase water demand in temperate regions while in tropical and subtropical regions, this may lead to water scarcity [22]. Further studies are needed to discover the most adoptive form of cropping system for specific regions keeping in view the climate change scenarios and for that agronomists need to work closely in the water management department. Change in climate may bring new disease, pests, and weeds that may cause serious problems for the crops. Some of the pests and weeds which are under economic injury level become problem by exploiting the changing condition [23]. Again, agronomists will need to work with the help of integrated pest management and integrated weed management and other tactics to help control the problematic weeds, pests,

The major role of agronomy is discovering new techniques for higher crop production without depleting natural resources and intensifying climate change. Choices for enhancing crop production safely involved extensification and intensification [13]. Extensification will help to raise the total quantity of production and contribute to increases in production, but increase through extensification is

According to Greenland et al. [24], more than 3 billion hectares of land is available for cultivation and can be used for good production and about 1.2–1.5 billion hectares of land is already cultivated. In general, further agriculture extensification will cause very limited increase in crop production. Typically, further extensification will contribute just 7.4% to cereal production while estimated extensification to crop production ranges from 18% in South Asia to 47% in sub-Saharan Africa by the year of 2020. To decrease the intensification of climate change and increase the extensification and intensification of farming practices in the subtropical and

limited due the availability of limited new land [15].

tropical areas should need to change with more resilience ones [15].

**4**

and diseases.

To assess the impacts of climate change on crop productivity and food security, agronomic research has thus provided an admirable basis. According to global harvest initiatives (2010), the global agricultural productivity must be increased by 1.75% to double the agricultural productivity by 2050. The average annual TFP growth rate in low-income countries is in trouble. However, Sustainable Development Goal 2 (SDG-2) calls for doubling of crop productivity for small-scale farmers in the lowest-income countries. But the current annual rate of TFP growth in low-income countries is just 0.96%. If this decline sustains for longer period, people in low-income countries will increase the use of soil and water, which are already threatened by extreme weather and climate change (**Figures 3** and **4**). Implementation of some farming practices has a significant impact and ecofriendly consequences at the watershed level. For example, growing of fruit trees on contours or other non-timber trees for the compensation of decline in crop yield could have a significant saving effect on water conservation and water use efficiency. This will provide a new way of farming to the farmers for increasing their income and will help to stabilize their socioeconomic status. Agronomists are needed to design such a productive agricultural system that is more suitable and resilient to the socioeconomic needs of the farming communities like poverty and hunger alleviation, food security, climate change adaptation, and environmental protection.

Increase in crop productivity is important to reduce food security problem; therefore, agronomic research is related to food security. Food security can be ensured by an efficient system of food, food production, and new research in the area of crop production. Food system is a set of continuous interaction between and within humans and their biogeophysical environment and it includes food production, processing, and food allocation and food consumption [25], while agronomy has an important role in these activities like producing food, by modern scientific methods and practices, storage and processing of staple food, and production timing in relation to market and food diversity in terms of nutritional balance. To this end, agronomic research needs to be better linked to wide-ranging interdisciplinary sectors and across sectors of the food industry. This will facilitate the building of integrated socioeconomic-biophysical models that will enable analysis of adaptation

**Figure 3.** *Agricultural output from TFP growth.*

#### **Figure 4.** *Economic survey of USDA.*

options to food systems, thereby underpinning policy formulation for improved food security and nutrition. The SDGs emphasize the importance of agriculture and the need to reinvigorate farming worldwide by supporting farmers, increasing investments in research, technology and market infrastructure, and extending knowledge sharing. This will catalyze innovation and empower farmers.
