**3. Perspective: toward an integrated chemical control against environmental stress**

Historically, the use of pesticides, irrigation, and fertilizers, especially chemical fertilizers, has proven highly successful in increasing crop yields and thus in meeting the demands of increasing population levels. However, recent climate change is having an adverse impact on crop production, and therefore, more efficient methods of crop production need to be established. The use of genetically modified organisms (GMOs) is undoubtedly a solution to combat losses in plant production caused by global environmental changes. However, GMO is limited to major crops, and its use is also either strictly restricted or not even permitted legally in several countries. Therefore, chemical control of abiotic stress tolerance is required as an alternative solution for ensuring unrestricted agricultural production.

**Conflicts of interest**

ABA abscisic acid

JA jasmonic acid

SA salicylic acid

**Author details**

Yasuo Yamauchi

**References**

BABA β-aminobutyric acid

PG phosphatidyl glycerol

PUFA polyunsaturated fatty acid

RSLV reactive short-chain leaf volatile

Address all correspondence to: yamauchi@kobe-u.ac.jp

Graduate School of Agricultural Science, Kobe University, Kobe, Japan

sectoral aspects: Cambridge University Press; 2014. p. 485-533

[1] Porter JR, Xie L, Challinor AJ, Cochrane K, Howden SM, Iqbal MM, Lobell DB, Travasso MI, Chhetri N, Garrett K, Ingram J, Lipper L, McCarthy N, McGrath J, Smith D, Thornton P, Watson J, Ziska L. Food Security and food production systems. In: Field CB, Barros VR, Dokken DJ, Mach KJ, Mastrandrea MD, Bilir TE, Chatterjee M, Ebi KL, Estrada YO, Genova RC, Girma B, Kissel ES, Levy AN, MacCracken S, Mastrandrea PR, White LL, editors. Climate Change 2014: Impact, adaptation, and vulnerability. PartA: Global and

Integrated Chemical Control of Abiotic Stress Tolerance Using Biostimulants

http://dx.doi.org/10.5772/intechopen.74214

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[2] Fujita M, Fujita Y, Noutoshi Y, Takahashi F, Narusaka Y, Yamaguchi-Shinozaki K, Shinozaki K. Crosstalk between abiotic and biotic stress responses: a current view from the points

ROS reactive oxygen species

GMO genetically manipulated organism

**Abbreviations**

The authors declare no conflict of interest.

**Figure 4.** Integrated chemical control of abiotic stress tolerance using biostimulants. Traditional countermeasures, such as irrigation and fertilizers, contribute to improving the basal level of crop production. On the other hand, unusual losses in crop yield caused by biotic and abiotic stress can be mitigated by pesticides and biostimulants, respectively. In this figure, unusual adverse events and biostimulants are boxed and underlined, respectively. The stresses targeted by traditional countermeasures and biostimulants are indicated by white and black arrows, respectively.

As introduced in this chapter, the use of biostimulants has potential as a powerful countermeasure for improving crop production under conditions of environmental stress. Traditional methods for enhancing yield, such as fertilizer and irrigation support, enable a basal level of production to be maintained (**Figure 4**). However, when crops are subject to unusual abiotic and/or biotic stresses, the transient use of adequate biostimulant(s) helps to overcome these stresses, sustaining production to at least the basal level, and sometimes bringing about an increase in crop production, as explained in **Figure 3**. Some biostimulants are already commercially available, and their use will become increasingly popular. However, there is still a lack of technical information for each biostimulant, such as the application period, concentration, and target plant species; these points must be established if biostimulant application is to become a reliable technique. Moreover, the combined use of biostimulants and traditional pesticides must be examined in order to realize the integrated chemical control of abiotic/biotic stress tolerance. In addition to the chemical biostimulants that are the focus of this chapter, other types of biostimulants that are derived from natural materials, such as microorganisms and algae, are also useful in reducing damage caused by abiotic stress [14, 15]. While the mode of action in chemical biostimulants can be explained scientifically, this is not the case for natural biostimulants. Therefore, more details on scientific analyses of the mechanisms used by biostimulants are necessary to support their availability for widespread use in the field.

### **Acknowledgements**

A part of unpublished data introduced in this chapter was generously provided by Phytochrome Inc. (Tokyo, Japan).
