**3. Post-harvest losses: tropical and subtropical fruit**

It is reported that about one-third of the production of food intended for human consumption is lost or wasted worldwide, which is roughly equivalent to 1.3 billion tons per year. This means that huge amounts of resources directed to food production are used in vain, and that greenhouse gas emissions caused by food production that is lost or wasted are also unnecessary [7]. A very significant part of the food that deteriorates or that is lost at post-harvest stage are fruits and vegetables. These losses occur throughout the management system of fruits during the harvest, transfer to the packinghouse, in the packing, during the storage, transportation and distribution to marketing centers. The causes of the losses in post-harvest are due to economic limitations, the lack of post-harvest technology as well as the lack of trained personnel about the knowledge in technology, management, physiology, and post-harvest pathology of horticultural products. This problem occurs mainly in developing countries, reaching up to 30 or 40% of post-harvest losses [8].

**5**

the MRL [20–22].

traceability (GLOBALG.AP) [23, 24].

*Alternative Eco-Friendly Methods in the Control of Post-Harvest Decay of Tropical…*

**4. Chemical methods: applications for post-harvest disease** 

Most of the post-harvest losses are attributed to the attack of a large amount of fungus in tropical and subtropical fruits. Chemical control of post-harvest diseases is widely used to maintain fruit quality [13]. There are a wide variety of fungicides for chemical control, and the vast majority is destined or directed to the pre-harvest applications, leaving aside the use in post-harvest stage [14, 15]. To make efficient the use of chemical fungicides, it is necessary to know both the pathogen and the fungicide. From the pathogen, it is necessary to know the genus and the species as well as their concentration found at pre- and post-harvest stages. On the part of the fungicide, it is necessary to know the mode and site of action, as well as the maximum residual limit (MRL) (**Table 1**) permitted on fruits and specific regulations where the fruit will be exported [16]. In **Table 1**, some fungicides used for post-harvest disease of tropical and subtropical fruit diseases are listed. The site and mode of action are summarized in the table, as well as the MRL that are allowed in the US [17] and the EU [18]. An important consequence for the inadequate use and irrational applications of chemical treatments is microbial resistance, and in this sense, it is recommended to alternate formulations to avoid this problem. Besides, post-harvest chemical control should be regionalized to the specific conditions and environment of each crop [19]. It is important to mention that agrochemical companies suggest the doses and formulations to use in a specific crop. At this point, public research centers have an important contribution, not only to verify the efficiency of fungicides but also to establish strategies for the efficient use of post-harvest chemical control [15]. Considering the new consumer tendencies, about secure products free of chemical residues, it is necessary to consider the rational use of chemical fungicides without exceeding

Therefore, the worldwide trend for both consumers and researchers is the reduction of the use of chemical fungicides and the research for biological, organic, and environmentally friendly alternatives. All this is under certification systems to guarantee the implementation, improvement, integration, and harmonization of all mechanisms to ensure a production of healthy and good quality fruit, with high

The fruits during their growth in the field are exposed to the attack of pathogenic fungi; they can be established as a latent infection in the fruit; and when the fruit begins its maturation process, the fungi can be activated and continue with their development, leading the deterioration of fruit. To control these pathogens, synthetic fungicides have been applied in a traditional manner; however, due to pollution and the environment issues, damage to the health of people and in general to living beings, as well as generating resistant strains of fungi, it is necessary to find alternatives to pathogen control [9, 10]. Currently, the research of alternative systems to the use of fungicides to control the losses caused by fungi, applying products of biological origin as well as organic and inorganic salts, among others, in order to control fungi infections, without contaminating the environment and without harming living beings has increased [11, 12]. Reducing the losses of post-harvest could solve the problem of hunger in many countries of the world, where not only it is producing more food but rather it is to conserve the food that is

*DOI: http://dx.doi.org/10.5772/intechopen.85682*

currently produced.

**management**

*Alternative Eco-Friendly Methods in the Control of Post-Harvest Decay of Tropical… DOI: http://dx.doi.org/10.5772/intechopen.85682*

The fruits during their growth in the field are exposed to the attack of pathogenic fungi; they can be established as a latent infection in the fruit; and when the fruit begins its maturation process, the fungi can be activated and continue with their development, leading the deterioration of fruit. To control these pathogens, synthetic fungicides have been applied in a traditional manner; however, due to pollution and the environment issues, damage to the health of people and in general to living beings, as well as generating resistant strains of fungi, it is necessary to find alternatives to pathogen control [9, 10]. Currently, the research of alternative systems to the use of fungicides to control the losses caused by fungi, applying products of biological origin as well as organic and inorganic salts, among others, in order to control fungi infections, without contaminating the environment and without harming living beings has increased [11, 12]. Reducing the losses of post-harvest could solve the problem of hunger in many countries of the world, where not only it is producing more food but rather it is to conserve the food that is currently produced.

#### **4. Chemical methods: applications for post-harvest disease management**

Most of the post-harvest losses are attributed to the attack of a large amount of fungus in tropical and subtropical fruits. Chemical control of post-harvest diseases is widely used to maintain fruit quality [13]. There are a wide variety of fungicides for chemical control, and the vast majority is destined or directed to the pre-harvest applications, leaving aside the use in post-harvest stage [14, 15]. To make efficient the use of chemical fungicides, it is necessary to know both the pathogen and the fungicide. From the pathogen, it is necessary to know the genus and the species as well as their concentration found at pre- and post-harvest stages. On the part of the fungicide, it is necessary to know the mode and site of action, as well as the maximum residual limit (MRL) (**Table 1**) permitted on fruits and specific regulations where the fruit will be exported [16]. In **Table 1**, some fungicides used for post-harvest disease of tropical and subtropical fruit diseases are listed. The site and mode of action are summarized in the table, as well as the MRL that are allowed in the US [17] and the EU [18]. An important consequence for the inadequate use and irrational applications of chemical treatments is microbial resistance, and in this sense, it is recommended to alternate formulations to avoid this problem. Besides, post-harvest chemical control should be regionalized to the specific conditions and environment of each crop [19]. It is important to mention that agrochemical companies suggest the doses and formulations to use in a specific crop. At this point, public research centers have an important contribution, not only to verify the efficiency of fungicides but also to establish strategies for the efficient use of post-harvest chemical control [15]. Considering the new consumer tendencies, about secure products free of chemical residues, it is necessary to consider the rational use of chemical fungicides without exceeding the MRL [20–22].

Therefore, the worldwide trend for both consumers and researchers is the reduction of the use of chemical fungicides and the research for biological, organic, and environmentally friendly alternatives. All this is under certification systems to guarantee the implementation, improvement, integration, and harmonization of all mechanisms to ensure a production of healthy and good quality fruit, with high traceability (GLOBALG.AP) [23, 24].

*Modern Fruit Industry*

pathogens in several crops.

**2. Fruit industry: importance in the world**

its contribution to human health [6].

**3. Post-harvest losses: tropical and subtropical fruit**

during the production chain [2]. In order to reduce the presence of pathogens, several post-harvest technologies have been applied [2]. One of them is the application of chemical fungicides; however, this practice is not accepted due to environmental and health issues [3]. Other alternatives are the use of eco-friendly substances such as generally recognized as safe (GRAS) compounds and emergent technologies like ultrasound and fogging. Currently, consumers demand fresh products free of chemical residues; therefore, it is necessary to develop technologies eco-friendly, effective to protect against pathogens infection, and that these technologies can maintain the fruit quality. Alternative systems such as edible coatings, essential oils, salts, natural compounds (plant extracts), among others to chemical use are suitable approaches for post-harvest disease management. These alternatives can be applied in combination with other control systems like emerging technologies (ultrasound) in order to improve their efficacy. The aim of this chapter is to make a compilation of several studies conducted on fruits for controlling important

Fruits and vegetables are essential sources for the micronutrients needed for healthier diets [4]. The potential of vegetables is to generate positive economic and nutritional impacts. The estimated farm gate value of annual global fruit and vegetable production, at nearly \$1 trillion per year, exceeds the farm gate value of all food grains combined (US\$ 837 billion). On the other hand, it is likely that the production of fruit and vegetable crops will not increase as rapidly as would be expected. Environmental changes can affect many different aspects of agricultural production. With greater climatic variability, temperature patterns and precipitation are some of the problems faced by fruit producers [5]. Technological advances have focused their efforts on the development of new varieties, crop management techniques, and innovations in postharvest handling and processing. Even in high-income countries such as the US, there is evidence that public funding for research in the agricultural area is less than expected, given its economic value and

It is reported that about one-third of the production of food intended for human consumption is lost or wasted worldwide, which is roughly equivalent to 1.3 billion tons per year. This means that huge amounts of resources directed to food production are used in vain, and that greenhouse gas emissions caused by food production that is lost or wasted are also unnecessary [7]. A very significant part of the food that deteriorates or that is lost at post-harvest stage are fruits and vegetables. These losses occur throughout the management system of fruits during the harvest, transfer to the packinghouse, in the packing, during the storage, transportation and distribution to marketing centers. The causes of the losses in post-harvest are due to economic limitations, the lack of post-harvest technology as well as the lack of trained personnel about the knowledge in technology, management, physiology, and post-harvest pathology of horticultural products. This problem occurs mainly in developing countries, reaching up to 30 or 40% of

**4**

post-harvest losses [8].


 *Common name, chemical group, mode and target site as well as its MRL in some fruits for consumption [23].*

**7**

**5.2 Essential oils**

*Alternative Eco-Friendly Methods in the Control of Post-Harvest Decay of Tropical…*

**5. Alternative methods in the control of post-harvest decay of tropical** 

eral investigations, chitosan has proved their efficacy for controlling several postharvest diseases. Several mechanisms of action have been proposed for chitosan:

a.Pathogens: the interaction of the biopolymer with the microorganism causes changes on cell permeability affecting biochemical processes like homeostasis, fungal respiration as well as nutrient uptake and the synthesis of proteins caus

b.Plants: induction of defense systems, by the production of important enzymes (phenylalanine ammonium lyase, polyphenol oxidase, among others) and plant immunity, favoring the adaptation of plants to biotic and abiotic stresses [25].

c.Fruits: the capability of chitosan to form mechanical barrier (coating) on fruits offers several advantages of coated fruits like a reduction on respiration rate, avoid water losses maintaining fruit firmness, maintenance of color, among

The induction of defense systems has been reported by the application of chito

β-1,3-glucanase and chitinase, involved in the

san at post-harvest stage, preventing the development and dispersion of important pathogens such as *Colletotrichum gloeosporioides*, *Alternaria alternata*, *Rhizopus stolonifer*, and *Fusarium oxysporum* [26–28]. Enzymatic activity is also affected by the curative application of chitosan, and it increases the activity of polyphenol oxidase (PPO), peroxidase (POD), and phenylalanine amino-lyase (PAL) that

defense against pathogens [29, 30]. The physiological mechanisms of the fruit are positively affected by the application of chitosan at post-harvest management under biotic and abiotic stress, that is why the post-harvest shelf-life and quality (firm

ness, appearance, color) of fruit can be maintained during the storage time, besides the respiration rate and ethylene production of fruits decrease [31]. Some studies reported an enhanced content of total soluble solids, ascorbic acid, the nutritional value, and acceptability [30, 32, 33]. Chitosan is compatible with other substances like organic salts, gums, or essential oils, and this alternative can improve their efficacy against pathogens due to a synergistic effect [34, 35]. Even when important information has been generated on the use of chitosan in post-harvest tropical and subtropical fruits, it is still necessary to generate information on the regulation (activation and suppression) of genes that participate in both systems of acquired resistance and those that control the processes physiological, enzymatic, and

The use of GRAS substances like essential oils (EOs) has increased in the last years,

due to the research of alternatives to chemical treatments for disease control [36]. Several investigations have reported the efficacy of essential oils *in vitro* and *vivo tests* [37–40]. The application of EOs in fruits has advantages such as: high effectiveness against several pathogens and low toxicity (nontarget microorganism and humans) [36]. EOs can be applied on fruits directly (vapor phase) or incorporated as active

others. Thus the shelf-life of fruits can be extended [36].

physicochemical factors of maturation in post-harvest.

The excessive use of agrochemicals in tropical and in subtropical fruit has leaded the search for new natural products, eco-friendly, and nontoxic to humans. In sev





*DOI: http://dx.doi.org/10.5772/intechopen.85682*

ing severe damage on fungal cells [12].

**and subtropical fruit**

induce the expression genes of

**5.1 Chitosan**
