A method for controlling post-harvest blackheart disease and waterheart disease in pineapples

Abstract

The present invention discloses a method for controlling postharvest blackheart and water core disease in pineapples. Within 12 hours after harvesting, the fruit is selected and dissipated at room temperature below 25°C. Water is heated to 50-63°C, and a 0-3% by mass calcium salt is added to create a hot solution. The solution is then placed at room temperature, and the pineapples are soaked in the hot solution for 1-20 minutes. The solution is then air-dried at room temperature before storage or sale. This method can be applied to postharvest pineapples before storage or sale. The process is simple, leaves no drug residue, is safe and non-toxic, and does not require large-scale equipment. It effectively controls postharvest blackheart and water core disease in pineapples, thereby extending their storage and shelf life.

Description

Technical Field

[0001] The invention belongs to the field of fruit disease prevention and treatment, and particularly relates to a method for controlling post-harvest blackheart disease and waterheart disease in pineapples. Background Art

[0002] Pineapple (Ananas comosus L.), a member of the Bromeliaceae family, is the third most popular tropical fruit, after bananas and mangoes. Compared to other provinces, Hainan Province boasts exceptionally abundant water, heat, and light resources, resulting in long summers and no winters. Pineapples are protected from frost damage, ensuring year-round availability, making it one of my country's leading pineapple-producing regions. Hainan's main pineapple variety, "Bali," boasts large, sweet fruits with a unique flavor. However, postharvest fruit is susceptible to blackheart disease or waterheart disease during storage and transportation. Existing research suggests that this is due to physiological imbalances caused by adverse environmental conditions, rather than pathogens, and the underlying mechanisms remain unclear. Currently, postharvest blackheart and waterheart disease in pineapples are not effectively controlled, significantly reducing the commercial value of the fruit. Our preliminary observations have shown that the onset of blackheart and waterheart disease in Hainan's main pineapple variety, "Bali," rarely overlaps. Blackheart disease primarily occurs from November to March, while waterheart disease primarily occurs during warmer months. Both diseases are difficult to detect visually, severely impacting fruit quality and threatening the healthy development of the pineapple industry. Therefore, the development of effective, simple-to-operate, green and environmentally friendly technology to control pineapple blackheart disease and waterheart disease has great practical significance and commercial value to my country's pineapple industry. Summary of the Invention

[0003] The invention aims to provide a method for controlling post-harvest blackheart disease and waterheart disease of pineapples.

[0004] The method for controlling post-harvest black heart disease and water heart disease of pineapples comprises the following steps: selecting pineapples and dissipating heat at a room temperature below 25 DEG C within 12 hours after picking, heating water to 50-63 DEG C, adding 0-3% by mass of calcium salt to prepare a hot solution, placing the solution at room temperature, soaking the pineapples in the hot solution for 1-20 minutes, drying the solution in an air-dried environment, and then storing or selling the solution.

[0005] Preferably, the temperature of the water is 55-60° C., and the soaking time is 10-15 minutes.

[0006] Preferably, the temperature of the water is 55° C. and the soaking time is 15 minutes.

[0007] The invention can be applied before storage or sale after harvest, has a simple process, no drug residue, is safe and non-toxic, does not require large-scale equipment, and plays a role in controlling black heart disease and water heart disease of pineapples after harvest, thereby extending the storage period and shelf life. DETAILED DESCRIPTION

[0008] In order to make the purpose, technical scheme and beneficial technical effect of the present invention clearer, the present invention is further described in detail below in conjunction with embodiment.It should be understood that the embodiment described in this specification is only for explaining the present invention, not for limiting the present invention, and the parameters, ratio etc. of embodiment can make selection according to local conditions and have no substantial effect on the result.Except otherwise specified, all in the embodiment are conventional reagents and method steps in this area.

[0009] Example 1:

[0010] (1) During the black heart disease period, pick pineapples that are 70% ripe. Within 12 hours after picking, cool them at room temperature below 25°C and select fruits with completely green skin and flat eyes for later use.

[0011] (2) Heat water to 55° C. and place it at room temperature. The temperature does not need to be kept constant. Soak the pineapple obtained in step (1) in the hot water for 15 minutes.

[0012] (3) The pineapple in step (2) is fished out, dried in the air at room temperature, and then stored at room temperature.

[0013] Example 2:

[0014] Heat water to 50°C and place it at room temperature (the temperature does not need to be kept constant). Place the selected pineapples with good heat dissipation into the hot water and soak for 10 minutes before taking them out. Other operations and technical requirements are the same as those in Example 1.

[0015] Example 3:

[0016] Heat water to 50°C and place it at room temperature (the temperature does not need to be kept constant). Add 1% calcium chloride by mass to make a hot solution. Place the selected pineapples with good heat dissipation into the hot solution and soak for 10 minutes before taking them out. Other operations and technical requirements are the same as in Example 1.

[0017] Example 4:

[0018] Heat water to 60°C and place it at room temperature (the temperature does not need to be kept constant). Add 2% calcium lactate by mass to make a hot solution. Place the selected pineapples with good heat dissipation into the hot solution and soak for 5 minutes before taking them out. Other operations and technical requirements are the same as in Example 1.

[0019] Comparative Example 1:

[0020] During the black heart disease outbreak period, pick pineapples that are 70% ripe. Within 12 hours after picking, dissipate heat at room temperature below 25°C. Select fruits with completely green skin and flat eyes and store them at room temperature.

[0021] Comparative Example 2:

[0022] During the blackheart disease outbreak, pick pineapples that are 70% ripe. Within 12 hours after picking, cool them at room temperature below 25°C. Select fruits with completely green skin and flat eyes for later use. At room temperature, soak the selected pineapples in room temperature water for 10 minutes, remove them, dry them at room temperature, and then store them at room temperature.

[0023] Comparative Example 3:

[0024] During the blackheart disease outbreak, pick pineapples that are 70% ripe. Within 12 hours after picking, cool them at room temperature below 25°C. Select fruits with completely green skin and flat eyes for later use. Soak the well-cooled pineapples in 40°C warm water at room temperature for 10 minutes, remove them, dry them at room temperature, and then store them at room temperature.

[0025] Eight days after treatment, the blackheart browning index and incidence of blackheart disease were recorded for each of the seven groups. The index was graded from 0 to 5 based on the area of browning on the fruit's cross section. Grade 0: No browning; Grade 1: Browning area less than 10% of the cross-sectional area; Grade 2: Browning area 11% to 20% of the cross-sectional area; Grade 3: Browning area 21% to 30% of the cross-sectional area; Grade 4: Browning area 31% to 50% of the cross-sectional area; Grade 5: Browning area greater than 50% of the cross-sectional area. The browning index and incidence of blackheart disease in pineapple fruit were calculated using the following formula.

[0026] Browning index = Σ[(number of fruits at this level × browning level) / (total number of fruits × highest browning level)] × 100

[0027] Blackheart disease incidence / % = (number of diseased fruits / total number of fruits) × 100%

[0028] Table 1 Browning index and blackheart disease incidence of pineapple in Examples 1-4 and Comparative Examples 1-3

[0029] deal with Browning index Blackheart disease incidence / % Example 1 17.78 50.00 Example 2 34.44 61.11 Example 3 28.88 55.56 Example 4 38.89 66.66 Comparative Example 1 72.00 90.00 Comparative Example 2 53.57 81.25 Comparative Example 3 56.67 83.33

[0030] Example 5:

[0031] (1) During the onset of water core disease, pick pineapples that are 70% ripe. Within 12 hours after picking, cool them at room temperature below 25°C and select fruits with completely green skin and flat eyes for later use.

[0032] (2) Heat water to 60° C. and place it at room temperature. The temperature does not need to be kept constant. Soak the pineapple obtained in step (1) in the hot water for 5 minutes.

[0033] (3) The pineapple in step (2) is fished out, dried in the air at room temperature, and then stored at room temperature.

[0034] Example 6:

[0035] Heat water to 50°C and place it at room temperature (the temperature does not need to be kept constant). Add 3% calcium lactate by mass to make a hot solution. Place the selected pineapples with good heat dissipation into the hot solution and soak for 15 minutes before taking them out. Other operations and technical requirements are the same as those in Example 5.

[0036] Example 7:

[0037] Heat water to 60°C and place it at room temperature (the temperature does not need to be kept constant). Add 3% calcium acetate by mass to make a hot solution. Place the selected pineapples with good heat dissipation into the hot solution and soak for 5 minutes before removing them. Other operations and technical requirements are the same as those in Example 5.

[0038] Comparative Example 4:

[0039] During the onset of water core disease, pick pineapples that are 70% mature. Within 12 hours after picking, dissipate heat at room temperature below 25°C and select fruits with completely green skin and flat eyes for storage.

[0040] Comparative Example 5:

[0041] During the onset of water core disease, pick pineapples that are 70% ripe. Within 12 hours after picking, cool them at room temperature below 25°C. Select fruits with completely green skin and flat eyes for later use. Soak the selected pineapples in room temperature water for 10 minutes, remove them, dry them at room temperature, and then store them at room temperature.

[0042] Eight days after treatment, the water core disease index and incidence rate of the five groups were recorded. The index was graded from 0 to 5 based on the water-soaked area on the fruit's longitudinal cross-section. Grade 0: No disease; Grade 1: Water-soaked area less than 10% of the cross-section; Grade 2: Water-soaked area 11% to 20% of the cross-section; Grade 3: Water-soaked area 21% to 30% of the cross-section; Grade 4: Water-soaked area 31% to 50% of the cross-section; Grade 5: Water-soaked area greater than 50% of the cross-section. The water core disease index and incidence rate of pineapple fruit were calculated using the following formula.

[0043] Disease index = Σ[(number of fruits at this level × disease level) / (total number of fruits × highest disease level)] × 100

[0044] Water core disease incidence / % = (number of diseased fruits / total number of fruits) × 100%

[0045] Table 2 Pineapple water core disease incidence index and water core disease incidence rate of Examples 5-7 and Comparative Examples 4-5

[0046] deal with Morbidity Index Incidence of water core disease / % Example 5 23.33 55.56 Example 6 25.56 50.00 Example 7 23.15 52.63 Comparative Example 4 66.09 91.30 Comparative Example 5 56.47 82.35

Claims

1. A method for controlling postharvest water core disease of pineapples, characterized in that: The method is to select the pineapples and dissipate heat at room temperature below 25°C within 12 hours after picking, heat the water to 50-63°C, add 0-3% calcium salt by mass to make a hot solution, place it at room temperature, soak the pineapples in the hot solution for 5-20 minutes, and then dry them at room temperature before storing or selling them.

2. The method according to claim 1, characterized in that The temperature of the water is 55-60° C., and the soaking time is 10-15 minutes.

3. The method according to claim 2, characterized in that The temperature of the water is 55° C., and the soaking time is 15 minutes.