Recycling of Date By-Product for Mass Rearing of Peach Fruit Fly, Bactrocera zonata (Saunders) (Diptera: Tephritidae)

Abstract

The world is currently facing a severe economic crisis and the rational consumption and reuse of products, including waste are necessary. Agriculture wastes have importance containing beneficial and economic value matters, which unutilized may lead to environmental pollution. Date seed is one of these viable wastes with high nutritional value. Mass rearing of peach fruit flies is important to produce parasitoids for use in biological control programs or sterile insect techniques. In this study powder of date seeds were evaluated as an alternative diet for mass rearing of peach fruit fly Bactrocera zonata. The nutrient composition of the tested diet that contained date seed powder was rich in crude proteins (13.1%), crude carbohydrates (40.41), crude fats (4.6), crude fibers (8.4), and ashes (0.29). The results indicated that the date seed powder produced insects with quality parameters equivalent to FAO, IAEA/USDA standards, without differences with those reared on yeast. The histology of the reproductive system of B. zonata reveals that the female ovariole is of meristic-polytrophic type with successive stages of egg chambers. The male testis has a single long follicle with successive stages of spermatogenesis. Thus, date seed powder is a potential alternative diet for use in the mass rearing of the peach fruit fly.

Keywords:
Alternative diet; biological control; date seed; peach fruit flies

HIGHLIGHTS

• Using date seed powder as Alternative for yeast in rearing of peach fruit fly, Bactrocera zonata.

• Date seed provide insects quality parameters corresponding to FAO, IAEA/USDA standards.

• Date seed costs less than yeast.

INTRODUCTION

The peach fruit fly, Bactrocera zonata (Saunders) (Diptera: Tephritidae), is a polyphagous pest of different crops, vegetables, and fruits [¹]. In Africa, B. zonata has been found in some commercially significant fruits [²,³].

For effective integrated management programs to control the peach fruit fly, sustainable diets for the mass rearing of that insects should be developed to assess its potential parasitoids, preferred hosts, and genetically modified strains [⁴]. To date, diets based on yeast have been used to rear B. zonata. The yeast has a direct consequence on the fecundity and fertility of the adult fruit flies, since it provides the essential growth factors for fruit flies, including peptides, minerals, vitamins, and amino acids [⁵].

Due to its economic and dietary benefits, the date palm (Phoenix dactyliferous L.) is one of the most widely grown trees and its fruit is an important agricultural product in Egypt, which is grown in a variety of locations, including Siwa, Marsa Maruth, and Alwadi Al gadid [⁶].

A surplus of issues, including environmental degradation, eutrophication, greenhouse gas emissions, and consequences on human health, are brought on by improper handling of organic waste. Recycling these organic wastes, which contain valuable plant material and organic matter, is a promising step to take advantage of their nutritional value and incorporate indirect environmental benefits. These wastes may also be used as effective chemical fertilizer replacements. Recycling agricultural wastes has significant economic benefits since it lowers costs compared with trash transportation, high import costs, and novel chemical fertilizers. Recycling and using organic wastes may contribute to reduce contaminants such as heavy metals and persistent agricultural wastes, which have serious environmental challenges [⁷].

Agriculture wastes, includes date seed ranging from 10% to 15% of the dates mass [⁸]. In 2018 more than 8 million tons of date fruit were produced, indicating that date seed represents a significant quantity of trash [⁹]. The potential production of date seed is approximately 800,000 tons, that has been partially used as soil fertilizer or animal feed [¹⁰].

Date seeds have about 8.8 - 9.6% moisture, 3.88 - 5.62% protein, 15.84 -18.01% crude fiber, 10.7 -8.5% ether extract, and 58.80 - 56.79% carbohydrates [¹¹].

The purpose of this study was to evaluate if date seed powder may be used as an alternative diet for mass rearing of the peach fruit fly, contributing to reduce of the use of expensive diets using yeast.

MATERIAL AND METHODS

1. Bactrocera zonata rearing under laboratory conditions

The peach fruit flies were obtained from the Laboratory of Plant Protection Research Institute, Dokki, Giza, Egypt, reared at 25±3 ºC, 60±5% R.H. and 12:12 h (L:D) photoperiod. Adult were kept in cages (110 cm length × 8 cm width × 85 cm height) and fed on sugar and protein hydrolysate (3:1) [¹²]. Small plastic orange-shaped perforated and filled with 2 cm of water was put inside the rearing cage as egg receptacle.

2. Artificial diet

The ratios of the various components required to prepare diets are displayed in Table 1. All diet components were weighed before being combined using a plastic rod to create a homogeneous diet. Briefly, the tested diet had the same amount of date seed power substituting yeast.

Table 1
Composition of larval diets tested for Bactrocera zonata.

Ingredients	Control Diet	Tested diet
Water	500 mL	500 mL
Sodium benzoate	3 g	3 g
Sugar	84.5 g	84.5 g
Citric acid	3 g	3 g
Wheat grain	330 g	330 g
Date seed powder	-	84.5 g
Yeast	84.5 g	-

3. Treatment

After preparation of the diets, 200 g were placed into plastic rearing pot. A small piece of black paper was moistened with water and placed in the median region of each pot of the diet. Then 100 eggs (one day old) were scattered onto the wet black paper. The pots were covered with muslin and incubated at 25±3 °C and 60±5% R.H and the number of hatched larvae counted daily. Five replicates with 100 eggs each were used to evaluate the quality control standards for fruit flies in the diets according [¹³].

Then the trays were transferred to plastic boxes (80 cm length × 8 cm width× 70 cm height) containing 1 cm of sand layer in the bottom for the larvae molt to pupae. The sand was sieved and the number of pupae counted. Three replicates of 50 newly-formed pupae were weighed after one day (one-day-old pupae). Five sets of 100 pupae were transferred to adult rearing cages with sugar and protein hydrolysate (3:1) to obtain the number of adult emergence.

4. Adult fliers and rate of fliers:

One hundred pupae in five replicates from each of the two different tested diets were placed at the bottom of black Plexiglas tubes (8.9 cm in diameter x 10 cm x 126 cm high); with the walls covered with127 unscented talcum powder [¹³], to determine the proportion of adult fliers. The surviving flies and pupae were counted after the adult flies left the tubes.

5. Biochemical analysis

Adults emerged from diets were homogenized separately in distilled water (1 g of insect mL^-1) using a chilled glass-Teflon tissue homogenizer. The samples were centrifuged at 8000 x g at 4 °C for 15 minutes, and the supernatant stored at -20 °C following use to determine the total protein content according [¹⁴], total carbohydrates [¹⁵], lipids [¹⁶], glutamic pyruvic transaminase (GPT), and glutamic oxaloacetic transaminase (GOT) [¹⁷].

6. Light microscope

To evaluate the reproductive parameters, 25 day old adult males and females (20 insects for each diet and sex) were anaesthetized with ether and dissected in saline solution (0.1 M NaCl, 0.1 M KCl). Then, the reproductive tracts were transferred to aqueous Bouin’s fixative solution for 24 h, washed and dehydrated in a graded ethanol series (70%, 80%, 90%, and 99%), cleared in xylene, and embedded in paraffin wax. Sections 6 µm thickness were obtained with rotatory microtome, stained with hematoxylin and eosin and analyzed using an Olympus BX51 microscope.

7. Analysis of the macronutrients from diets

The macronutrients from the control and tested diets were evaluated in the Haram-Giza Center for Bread Technology. Percentage of crude protein, lipids, fibers, water, and ash were determined according to [¹⁸]. Total carbohydrate (%) was estimated according to Shumaila & Mahpar [¹⁹].

8. Statistics

A t-Student test was used to compare the variations in quality metrics and nutritional levels for flies grown on the investigated diets. The same test was used to compare the nutritional components of the diets. The statistical analyses were performed using IBM SPSS Statistics Version 22 at 5% of significant level.

RESULTS

The values for the evaluated quality control parameters of peach fruit fly were similar between both diets tested. The percentage of egg hatchability, pupae, adult emergence, flying ability and flying rate were 97.7, 96.7, 95, 99, and 99.7 for insects reared on control diet, respectively and 97.33, 96, 94.3, 98.7, and 99.7 with diet containing date seeds power, respectively (Figure 1).

Figure 1
Quality control parameters (mean ± SE) for Bactrocera zonata (Diptera: Tephritidae) reared on the two larval diets. Diet A - control. Diet B - treated with date seeds powder. Bars with same letter are similar by t-Student test at 5% significance level.

The percentage of total protein, carbohydrate and lipids in the body of male and female flies were higher in diet with date seeds powder than in the control (Figures 2 and 3), whereas the GOT and GPT body content for male and females flies were similar between the diets (Figures 2 and 3).

Figure 2
Nutrient content (mean ± SE) in the male body of Bactrocera zonata (Diptera: Tephritidae) adult reared on different larval diets. Diet A - control. Diet B - treated with date seeds powder. Bars with different letters differ by t-Student test at 5% significance level. GOT - glutamic oxaloacetic transaminase, GPT - glutamic pyruvic transaminase.

Figure 3
Nutrient content (mean ± SE) in the female body of Bactrocera zonata (Diptera: Tephritidae) adult reared on different larval diets. Diet A - control. Diet B - treated with date seeds powder. Bars with different letters differ by t-Student test at 5% significance level. GOT - glutamic oxaloacetic transaminase, GPT - glutamic pyruvic transaminase.

In both diets, female reproductive tract mature at 21-22 days after adult emergence, but male reproductive system matures at the end of the first week of adult lifespan. The ovary of peach fruit fly consists of meroistic-polytrophic ovarioles, with egg follicles in different stage of development (Figure 4). Each egg follicle has one oocytic chamber and a nurse chamber, both surrounded by follicular epithelium (Figure 4).

Figure 4
a. Light micrograph of female ovary of Bactrocera zonata adults resulted from larvae feed on Diet A-control showing mature egg chamber of female ovary. b. Light micrograph of female ovary of Bactrocera zonata adults resulted from larvae feed on Diet B-treated with date seeds powder showing mature egg chamber of female ovary where (Oc) oocyte, (Nc) nurse cell, (Nu) nurse cell nucleus, (Fc) follicular cell epithelium, and (N) follicular cell nucleus.

The male testis showed follicles with spermatogonia and spermatocytes at different stage of development (Figure 5). Each spermatocyte undergoes the meiotic division to produce spermatids (Figure 5). The spermatids in the cysts differentiated into spermatozoa (the zone of transformation; Figure 5). The whole testis is surrounded by a peritoneal sheath (Figure 5).

Figure 5
a, b. Light micrographs of male testis of Bactrocera zonata adults resulted from larvae feed on Diet A-control showing male testis. c, d. Light micrographs of male testis of Bactrocera zonata adults resulted from larvae feed on Diet B-treated with date seeds powder showing male testis where (Sp) spermatogonia, (Sc) spermatocytes, (St) spermatid, (Sz) spermatozoa, and (Tw) testis cell wall.

The analyses of nutrients varied between diets (Figure 6). Control diet showed higher protein content (22%) than diet with date seeds powder (13.1%; t = 26.7, df = 4, p < 0.05; Figure 6). Carbohydrates content was higher in diet with date seeds powder (40.41%) than control ones (30.35%; t = -17.18, df =4, p < 0.05). Ash, fats, fibers, and moisture were similar in both diets (Figure 6).

Figure 6
Assessment the different nutrient components of the different tested artificial larval diet (mean ± SE). Diet A - control. Diet B - treated with date seeds powder. Bars with different letters differ by t-Student test at 5% significance level.

DISCUSSION

The quality control parameters of B. zonata, including egg hatchability, pupae, adult emergence, flying ability, and flying rate, reveal no differences between insects reared with the different diets. These findings are in agreement with those found by Abdel-Hafeez and coauthors [²⁰] that have pointed out absence of difference in emergence percentage and flight ability in Ceratitis capitata (Diptera: Tephritidae) larvae reared on conventional yeast artificial diet and that with date seeds powder. Also these results are in harmony with Maset and coauthors [²¹] that determined the optimal artificial larval diet and the respective larval density for C. capitata on diets based on corn flour, sugarcane bagasse, and lyophilized carrot powder, considering biological parameters of quality control and economic viability. According to FAO/IAEA [¹³] our findings shown that date seed powder diet produces pupae >7.5 mg in weight and 93% of adult emergence.

The analyses of insect body to verify how the feeding of peach fruit larvae is affected by the nutrient content of the tested diets reveal higher protein, carbohydrate and lipid in flies emerged from diet with date seeds powder than that with yeast. The obtained data agree with those from Rendon and coauthors [²²] that examined how body nutrient contents of an invasive fly, Drosophila suzukii were affected by dietary protein and carbohydrate showing that flies that received rich-protein diet have lower carbohydrate, protein and, lipid body content compared to flies fed on rich-carbohydrate and poor-protein in their diets.

The ovariole of B. zonata female likely all other Diptera, is of meristic polytrophic type [²³]. Shehata and coauthors [²⁴] found that the ovaries of a newly-emerged B. zonata male are underdeveloped and they reached maturity on the 21^st or 22^nd day of adult lifespan. Bactrocera zonata males reared on both diets reach maturity at the end of the first week of adult male lifespan, which has been characterized by the presence of all spermatogenesis stages in the testis follicle [²⁵]. Together, these findings indicate that diet with date seed powder is suitable for reproduction of the peach fruit fly.

Our findings shown that the percentage of carbohydrates is higher than protein in diet based on date seed powder. These two components in larval diets of fruit flies are responsible basically on the body size, development and survival of adults [²⁶]. Behmer [²⁷] hypothesized that whereas some phytophagous insect larvae prefer high-protein diets, others prefer diets high in carbohydrates. As demonstrated by Hafsi and coauthors. [²⁸], polyphagous tephritids have different dietary needs from oligophagous tephritids and the performance of polyphagous species is invasive fly, D. suzukii associated with diets rich in lipids, carbohydrates, and fibers but not proteins. Date seeds powder diet here evaluated contain 13.1% of proteins, similar to the suitable amount for larval rearing artificial diet of oriental fruit flies [²⁹]. High carbohydrate content in larval artificial diets with wheat germ produce peach fruit flies with good quality parameters [³⁰].

The low crude fats content in the both diet tested here has no effect on the quality of peach fruit flies between the tested artificial diets. Diets based on wheat germ with ca. 3% fats are suitable for rearing of peach fruit fly with quality parameters equivalent to FAO/ IAEA/USDA standards [³⁰].

The fiber content of diet with date seeds powder is similar to that with yeast about 10%. The fiber content is essential in insect mass rearing for permitting a most favorable milieu for larval development [²⁹]. The suitable crude fiber content has been claimed to range from 5 to 26% [³¹], which occurs in the diets here evaluated.

CONCLUSIONS

Date seed powder used in an artificial diet for mass rearing of peach fruit fly B. zonata as alternative for that with yeast provide insects with good quality parameters, including biochemical components and reproduction, but with lower costs than diets rich in yeast. Overall, our findings provide evidence that date seed powder may be used in the mass rearing of peach fruit fly that are used for sterile insect technique or to produce parasitoid for use in biological control programs.

REFERENCES

• ¹
  Murtaza G, Naeem M, Manzoor S, Khan HA, Eed EM, Majeed W, Makki HA, Ramzan U, Ummara UE. Biological control potential of entomopathogenic fungal strains against peach Fruit fly, Bactrocera zonata (Saunders) (Diptera:Tephritidae). PeerJ. 2022 April; 10:;e13316.doi: 10.7717/peerj13316.
  » https://doi.org/10.7717/peerj13316.
• ²
  Allwood AL, Chinajariyawong A, Drew RAI, El Hamacek DL, Hancock C, Hengsawad JC, Ji-Panin M, Jirasurat C, Kong Krong S, Krit-Saneepaiboon CTS, Vijaysegaran S. Host plant records for fruit flies (Diptera: Tephritidae) in Southeast Asia. Raffles Bull. Zool.1999;7(47):1-92.
• ³
  Leblanc L, Bhandari BP, Aryal LN, Bista S. New country records and annotated checklist of the dacine fruit flies (Diptera: Tephritidae: Dacini) of Nepal. Proc. Hawaiian Ent. Soc. 2019 December;51(2):39-46.
• ⁴
  Ribeiro I, Pereira R, Vidal FI, Oliveira B, Casotti C, Boery E. Stress and quality of life among University Students: A Systematic Literature Review. Health Professions Education. 2017 April;4(2):70-7.doi:org/:10.1016/j.hpe.2017.03.002
  » https://doi.org/10.1016/j.hpe.2017.03.002
• ⁵
  Schroeder WJ, Miyabara RY, Chambers DL. Protein products for rearing three species of larval Tephritidae. J. Econ. Ent.1972 August; 65(4):969-72.doi:10.1093/jee/65.4.969
  » https://doi.org/10.1093/jee/65.4.969
• ⁶
  Al-Alaw R, Al-Mashiqri JH, Alnadabi JSM, Al-Shihi BI, Baqi Y. Date palm tree (Phoenix dactyliferous L.): Natural products and therapeutic options. Frontiers Plant Sci. 2017 May;8 (845):1-12. doi:10.3389/fpls.2017.00845
  » https://doi.org/10.3389/fpls.2017.00845
• ⁷
  Sharma B, Vaish B, Singh UK, Singh P, Singh RP. Recycling of organic wastes in agriculture. An environmental perspective. International J. Environ. Res. 2019 April; 13: 409- 429.doi:10.1007/s41742-019-00175-y
  » https://doi.org/10.1007/s41742-019-00175-y
• ⁸
  Besbes S, Blecker C, Deroanne C, Drira NE, Attia H. Date seeds: Chemical composition and characteristic profiles of the lipid fraction. Food Chem. 2004 March; 84: 577-584.doi:/10.1016/S0308-8146%2803%2900281-4
  » https://doi.org/10.1016/S0308-8146%2803%2900281-4
• ⁹
  FAOSTAT. Date, The Food and Agriculture Organization of the United Nations. Available from: http://www.faostat.fao.org/ faostat/en/#data/QC.2018
  » http://www.faostat.fao.org/ faostat/en/#data/QC.2018
• ¹⁰
  Vandepopuliere JM, Al-Yousef Y, Lyons JJ. Dates and date pits as ingredients in broiler starting and coturnix quail breeder diets. Poultry Sci.1995 July; 74 (7):1134 - 42. doi:10.3382/ps.0741134.
  » https://doi.org/10.3382/ps.0741134.
• ¹¹
  Ahfaiter H, Zeitoun AM, Abdalla AE. Physicochemical properties and nutritional value of Egyptian date seeds and its applications in some bakery products. J. Adv. Agric. Res. 2018 June;23(2):260-78.
• ¹²
  Shehata NF, Younes MWF, Mahmoud YA. Anatomical effects of gamma-ray on the peach fruit fly, Bactrocera zonata (Saund.) male gonads. J. Appl. Sci. Res. 2006 January; 2 (8): 510-3.
• ¹³
  FAO/IAEA. Product quality control for sterile mass-reared and released tephritid fruit flies. 2014; 403. Vien
• ¹⁴
  Bradford MM. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal. Biochem.1976 May;72(7): 248- 54.doi:10.1006/abio.1976.9999.
  » https://doi.org/10.1006/abio.1976.9999.
• ¹⁵
  Dubios M, Gilles KA, Hamilton JK, Rebers PA, Smith F. Colorimetric method for determination of sugars and related substances. J. Anal. Chem.1956 July; 28:350-6.doi:10.1038/168167a0.
  » https://doi.org/10.1038/168167a0.
• ¹⁶
  Knight JA, Anderson S, Rawle JM. Chemical basis of the sulfophospho-vanillin reaction for estimating total serum lipids. J. Clin. Chem.1972 March; 18(3): 199-202.
• ¹⁷
  Reitman S, Frankel S. Colorimetric method for aspartate and alanine transaminases. Am.J.Clin.Pathol.1957 July; 28(1): 56-63.doi:10.1093/ajcp/28.1.56
  » https://doi.org/10.1093/ajcp/28.1.56
• ¹⁸
  A.O.A.C.Official Method of Analysis of the Association of Official Analytical Chemists,2000; 17thedn.(ED. Horwitz W.). Washington, DC.
• ¹⁹
  Shumaila G, Mahpar S. Proximate composition and mineral analysis of cinnamon. Pak. J. Nutrit. 2009 September; 8(9):1456-60 doi:10.3923/pjn.2009.1456.1460
  » https://doi.org/10.3923/pjn.2009.1456.1460
• ²⁰
  Abdel-Hafeez TA, Elzouk AA, El-Maaboud A. Preliminary tests for alternative low cost protein sources for the artificial larval diet of Mediterranean fruit flies Ceratitis capitata (Diptera:Tephritidae). Egyp. J. Plant Prot. Res. Inst. 2021 March; 4(1): 10-6.
• ²¹
  Maset BA, Demetrio CGB, Lopes LA, Costa MLZ, Botteonv W, Mastrangelo TA. Which artificial larval diet is better for Ceratitis capitata (Diptera: Tephritidae) rearing? J. Basic Appl. Zool. 2022 October; 83: 1-11. doi: 10.1186/s41936-022-00312-8
  » https://doi.org/10.1186/s41936-022-00312-8
• ²²
  Rendon D, Walton V, Tait G, Buser J, Souza L., Wallingford A, Loeb G, Lee J. Interactions among morphotype, nutrition, and temperature impact fitness of an invasive fly. Ecol. Evol. 2019 February; 9(5): 2615- 28.doi:10.1002/ece3.4928.
  » https://doi.org/10.1002/ece3.4928.
• ²³
  Negm AAKH, Gabarty A, Elelimy HAS. Ultra structure and histopathological alteration in the ovaries of Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) induced by x-ray radiation. Egyp. Acad. J. Biol. Sci. 2022 December; 15(4): 171-82: doi:10.21608/EAJBSA.2022.274616
  » https://doi.org/10.21608/EAJBSA.2022.274616
• ²⁴
  Shehata NF, Younes MWF, Mahmoud YA. Anatomical and histological studies on the peach fruit fly, Bactrocera zonata (Saund.) Female reproductive system. J. Appl. Sci. Res. 2011 January; 7(7): 1212-7.
• ²⁵
  Shehata NF, Younes MWF, Mahmoud YA. Anatomical and histological studies on the peach fruit fly, Bactrocera zonata (Saund.) male reproductive system. J. Appl. Sci. Res. 2010 January; 6 (9): 1346-51.
• ²⁶
  Nash WJ, Chapman T. Effect of dietary components on larval life history characteristics in the medfly Ceratitis capitata (Diptera:Tephritidae). PLoSOne. 2014 January; 9(1): e86029: doi:10.1371/journal.pone.0086029
  » https://doi.org/10.1371/journal.pone.0086029
• ²⁷
  Behmer ST. Insect herbivore nutrient regulation. Annu. Rev. Ent. 2009; 54:165-187. doi:10.1146/annurev.ento.54.110807.090537.
  » https://doi.org/10.1146/annurev.ento.54.110807.090537.
• ²⁸
  Hafsi A, Facon B, Ravigné V, Chiroleu F, Quilici S, Chermiti B, Duyck PF. Host plant range of a fruit fly community (Diptera: Tephritidae): does fruit composition influence larval performance? BMC Ecol.2016 September; 16(1): 2-12: doi:10.1186/s12898-016-0094-8
  » https://doi.org/10.1186/s12898-016-0094-8
• ²⁹
  Salmah M, Nurul-Fatihah MY, Hailmi MS, Norhayati N. Growth and development of oriental fruit fly, Bactrocera dorsalis Hendel (Diptera: Tephritidae) reared on sweet potatoes (Ipomoea batatas L.) based artificial diet. Serangga.2020 August; 25(2): 96-107.
• ³⁰
  Negm AAKH. New alternatives to the artificial diet used for mass rearing of peach fruit fly larvae, Bactrocera zonata (Saunders) (Diptera: Tephritidae). Egyp. Acad. J. Biol. Sci. 2020 July; 13(3):15-25: doi:10.21608/EAJBSA.2020.101994.
  » https://doi.org/10.21608/EAJBSA.2020.101994.
• ³¹
  Fay HAC. Multi-host species of fruit fly. In Robinson AS & Hooper G (eds.). World Crop Pest. Fruit Flies, Their Biology, Natural Enemies and Control, 1989;129-38. New York: Elsevier.

• Funding:

  This study was supported by Agricultural Research Center, Plant Protection Research Institute and Cairo University, Faculty of science.

Edited by

Editor-in-Chief:

Bill Jorge Costa

Associate Editor:

Bill Jorge Costa

Publication Dates

• Publication in this collection
  04 Aug 2023
• Date of issue
  2023

History

• Received
  03 Mar 2023
• Accepted
  03 Apr 2023