**Abstract**

Climate change is a global threat to food security as it causes various biotic and abiotic stresses that adversely disturb agriculture production. With an increase in the worldwide population, the demand for food has also arisen. It is an immediate challenge for the scientific community to introduce an innovative tool to achieve food security with quality plant production and develop tolerance against abiotic stresses, specifically drought. Genetically modifications are effective and time-consuming, while biostimulants are in/organic substances with the potential to support plant development under stress conditions. This chapter focuses on the impacts of climate change on agriculture, challenges for agriculture sustainability and food security, the interrelationship between drought, climate change and food security, the potential role of biostimulants against drought, future aspects and challenges due to climate change specifically drought, and food security challenges. Various studies reported that the application of biostimulants results in enhancement of crop productivity and mitigates the harmful effects due to climate change. To ensure the quality of chapter, we collected references from well-reputed international journals using keywords ""biostimulants," "drought," "food security," "agriculture sustainability," and "climate change." In conclusion, biostimulants has a potential to address adverse environmental conditions without affecting crop quality and yield loss.

**Keywords:** abiotic stress, biostimulants, climate change, food security, drought stress

### **1. Introduction**

The world population has doubled since 1960, resulting in increased food demand and agricultural production [1]. World food production needs to be increased to 70% to feed this population in 2050 [2]. Due to high warming temperatures and precipitation shifts, agriculture has faced a massive yield decline, especially in lower latitudes [3]. Global warming speeds up crop development and reduces the maturity time and photo-assimilation period thus disturbs crop yield and quality. Moreover,

such climatic conditions are more optimistic for pests. During the growing season, the climatic water balance has been projected to increase negatively, leading to water shortage [4]. Furthermore, it also affects the stomatal closure, cell damage, delayed seed germination, disturbed structure and functionality of cell membranes, enzyme inactivity, and interferences on protein synthesis, ultimately damaging crop productivity [5].

Drought is another environmental hazard described as a long period of reduced precipitation occurring in almost all climatic zones, including low and high rainfall [6]. Crop productivity and yield depend upon irrigation management, water quality, and regimes. At the same time, water shortage disturbs gaseous exchange, photosynthetic activity, evapotranspiration, stomatal closure, and nutrient uptake and consequently affects plant biomass [1]. Drought stress events are mainly associated with low rainfall and high soil evaporation due to high-temperature events, dry wind, and high light intensity. Scientists and agriculturists have introduced various drought-resistance induction strategies to cope with drought and other global warming impacts [7].

Biostimulants are substances having the potential to improve nutrient use efficiency and uptake, develop resistance against biotic and abiotic stresses, and improve quality characteristics when applied to plants [8]. Moreover, biostimulants vary in composition depending on the material used in their preparation. It enhances plant growth and nutrition when applied in minute quantities; therefore, it should not be termed as fertilizers and other soil amendments used in considerable amounts to achieve the required yield [9]. Studies reported that paramylon [10], commercial *Ascophyllum nodosum* extracts [11], and exogenous application of melatonin developed drought resistance and improved tomato quality [12]. Under drought conditions, mint quality and quantity were improved using biostimulants [13].

The objectives of this chapter were to identify the impacts of climate change on agriculture sustainability and the role of biostimulants in drought. Climate change has adversely impacted the agriculture sustainability while the biostimulants are gaining popularity due to its potential in addressing abiotic stresses. Therefore, the chapter focuses on provided the alarming signals about climate change and how farmers and other landholders can use biostimulants to achieve food security. The chapter consists of eight sections, which include the introduction (Section 1), methodology (Section 2), impacts of climate change on agriculture, both biotic and abiotic stresses (Section 3), challenges for agriculture sustainability and food security (Section 4), the interrelationship between drought, climate change, and food security (Section 5), potential role of biostimulants against drought (Section 6), future aspects and challenges (Section 7), and conclusion (Section 8), respectively.
