الفهرس 
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Abstract
The present study was conducted refrigerator (Baraka refrigerator), Kafr Saad, Damietta Governorate, Egypt, during the two successive summer seasons of May, 2021 and 2022. The experiments were designed to investigate the effects of anti-sprouting agents for inhibiting tuber sprouting, increase storability and quality using natural compounds. Potato tubers (Lady Rosetta and Hermes cvs) were exposed each treatment with natural essential oil as well as CIPC and Fresh Back and were stored for five months at cold temperature (10 oC day/night and 95% RH).The experimental design was a full factorial experiment 2x8 factorial scheme with three replicates. The experiment included 16 treatments which the interaction between two cultivars and eight treatments, which were as follows: (1) storing potato tubers without any application as control, (2) chloropropham (CIPC), (3) Fresh-Back®-50EC, (4) mint oil, (5) caraway oil, (6) clove oil, (7) sage oil, and (8) lavender oil. Each experimental unit was constituted by a single red plastic bag weighed 25 kg. The tubers were exposure to the pure essential oils after 15 Ds of harvesting. Pure essential oils were prepared of 5 ml concentration of each compound. Control tubers were not treated with any compounds. Tubers were treated for 5 hours in a room temperature jointed with a refrigerator. Pure essential oils were applied to tubers by thermal fogger machine (Super-2000 Gold sprayer, South Korea). CIPC named SPUD-NIC 4A (49.7% w/v chloropham) use at 33 ml/ton of stored potatoes. CIPC will typically apply with a thermal applicator at high temperatures to create an aerosol or thermal fog Fresh-Back®-50EC treatment solutions of 84 ml/ton may be used by fogging machine as natural essential oils. The obtained results could be summarized as follows:1. Sprouting, weight loss and damage percentages:1.1. Effect of potato cultivars:After 150 days storage, tubers of Hermes cultivar were significantly lower sprouting, weight loss and decay percentages than those of Lady Rosetta cultivar in both seasons.1.2. Effect of storage treatments:Treatments of clove oil have been fully (100%) inhibited bud development and incidence of sprouting, greatly reduced weight loss incidence and fully prevented of tubers decay compared with other treatment in both seasons followed by CIPC and Fresh Back in completely suppressed sprouting, weight loss and damage incidence of their tubers during both seasons.1.3. Effect of interaction:Tubers of Lady Rosetta and Hermes cultivars treated with CIPC or clove oil were of lowest sprouting, weight loss and damage percentage in comparison with all storage treatments during the two seasons.2. Tubers quality (Carbohydrate, starch, reducing sugars, non-reducing sugars and total sugars):2.1. Effect of potato cultivars:The tubers of Lady Rosetta cv. were significant higher in carbohydrate, starch, and lower reducing sugars, non-reducing sugars and total sugars than those of Hermes tubers in both seasons except for total carbohydrates % in 2022 season.2.2. Effect of storage treatments:All storage treatments significantly surpassed the control one in their tuber bio-constituents, i.e., total carbohydrates and starch and lower reducing sugars, non-reducing and total sugars during the two seasons. CIPC, Fresh Back and clove essential oils gave highest significant values of total carbohydrates and starch and lowest significant ones on reducing, non-reducing and total sugars in comparison with other treatments during two seasons. 2.3. Effect of interaction:The applied CIPC, Fresh Back and clove oil to Lady Rosetta were greatly preserved total carbohydrates and starch content during long term storage period compared with those of other treatments in both seasons. On the other hand, tubers of control treatment gave the lowest significant differences in carbohydrates and starch content. At (10C) all essential oils induced the lowest values of reducing sugars, maintain the same time the lowest values of non-reducing sugars and total sugars content.3. Tubers quality and antioxidants content:3.1. Effect of potato cultivars:Lady Rosetta tubers were of higher significant dry matter and total phenols content than Hermes cultivar with no significant differences between them on vitamin C in both seasons at the end of storage period.3.2. Effect of storage treatments:Tuber dry matter, vitamin C and total phenol content were significantly affected by the use of applied essential oils. The highest significant values of most parameters were shown by tubers treated with CIPC, Fresh Back and clove oil compared to other treatments and control in both seasons expect for total phenols in 2021 season.3.3. Effect of interaction:Treated potato tubers of Lady Rosetta cultivar with CIPC, Fresh Back and clove oil essential oil at 10oC gave the highest significant values of DM, vitamin C and Total phenols compared with other treatments at the end of storage periods at two seasons.4. Phytohormones and enzymatic activity:4.1. Effect of potato cultivars:Tubers of Lady Rosetta were of higher significant abscisic acid (ABA) and polyphenol oxidase (PPO) in both seasons and peroxidase (POD) in 2nd season than Hermes cultivar. Hermes had a significant value of gibberellic (GA3) content in both seasons.4.2. Effect of storage treatments:Tubers of all treatments at 10C showed that GA3, ABA, POD and PPO were significantly affected by the use of applied essential oils. Applied of clove oil was significantly increased in tuber ABA hormone POD and PPO content and reduced in tuber GA3 in both seasons.4.3. Effect of interaction:Treatments of clove oil and CIPC gave the highest values of ABA in Lady Rosetta and Hermes tubers in two seasons.Both cultivars treated with clove oil were significantly higher in POD activity in both seasons. Clove oil x Lady Rosetta had a significant effect on PPO content in comparison with another cultivar treated with different essential oils in two seasons of study. On contrary, untreated tubers in both cultivars gave the highest significant value of GA3 content in the end of storage period (150 DAS) in both seasons.5. Processing quality of potato chips:5.1. Effect of cultivars:Lady Rosetta gave the higher significant chips quality characters, i.e., color, crispiness, taste and firmness than Hermes one in the two seasons expect crispiness quality in the first season.5.2. Effect of essential oils:Clove oil, CIPC and Fresh Back treatments were significantly superior the control and other treatments in all parameters of processing chips quality (colour, crispiness, taste and firmness) in the two seasons.5.3. Effect of interaction:All treatments of interaction between cultivars and essential oils gave the highest values of processing quality parameters compared with control treatments of each of them. However, the differences among these treatments in mentioned parameters were less significant.The same data show that the most beneficial treatments of the best chips quality characters were Lady Rosetta or Hermes x CIPC, Fresh Back and clove oils in comparison with other treatments in both seasons.6. Processing quality of potato French fries:6.1. Effect of cultivars:Lady Rosetta gave the higher significant color French fries quality character than Hermes one in first season. No significant differences between them in second season. Lady Rosetta gave the higher significant crispiness French fries quality character than Hermes one in both seasons. No significant differences between them on taste in both seasons.6.2. Effect of essential oils:Clove oil treatment gave the highest French fries quality characters, i.e., color in two seasons. Caraway oil treatment gave the highest French fries characters, i.e., crispiness in two seasons. Lavender oil treatment gave the highest French fries characters, i.e., taste in two seasons in comparison with the control treatment.6.3. Effect of interaction:All treatments of interaction between cultivars and essential oils gave the highest values of French fries processing quality parameters compared with control treatments of each of them. However, the differences among these treatments in mentioned parameters were less significant.The same data in show that the most beneficial treatments of the best chips quality characters were Lady Rosetta x Fresh Back, Lady Rosetta or Hermes x clove oils in comparison with other treatments in both seasons. 7. Fresh-cut of potatoes: The visual quality of potato fresh-cut in different period storage at 2oC as affected by selected treatments of storage experiments. Overall visual quality score of treated slices with clove oil x lady rosette was reduced slightly, after 12 days of storage at 2°C and was significantly different from the untreated slices followed by Hermes x clove oil treatment. After the same period of storage, there was a marked decrease in the visual quality of control slices and differences increased after 9 days of storage.The weight loss percentage of potato fresh-cut in different period storage at 2oC as affected by selected treatments of storage experiments. Tubers of Lady Rosetta or Hermes treated with clove oils were of significant lower weight loss percentage than those of Lady Rosetta or Hermes not treated one in average of two seasons.The smallest decrease in the AA content was observed in Lady Rosetta x clove oil followed Hermes x clove oil and the largest in control of both cultivars, during the 15 days of cold storage The lowest TP in the fresh-cut potato samples assessed was found control of both cultivars during cold storage, whereas the highest TP was observed in Lady Rosetta treated with clove oil followed Hermes cultivar treated one after 15 days of storage. The smallest increase in TSS was observed in control treatments of both cultivars, whereas the largest increase was found in Lady Rosetta or Hermes treated with clove oils, during the entire cold storage period.7. Economic evaluation:The highest net return (L.E.3400/ton) was obtained from application of clove oil treatment when applied as fumigation technique on Lady Rosetta cultivar at temperature (8°C) followed by CIPC or Fresh Back x Lady Rosetta (L.E. 3375/ton and L.E. 3269/ton, respectively) and Hermes x clove oil (L.E. 2900/ton) in comparison with other treatments. Thus, this treatment proved to be highly economical for potato storing.CONCLUSION The study suggests using clove oil with Lady Rosetta or Hermes cultivars once time before storage at a rate of 100 ml/ton by fogging and stored potato tuber at 10 oC day/night and 95% RH for 5 months as an efficient natural to reduce sprouting, weight loss and damage percentages with an increase in its content of biochemical compounds, antioxidant enzymes and abscisic acid for storing potato tubers for the purposes of processing chips and French fries. Moreover, the essential oils are safe for use not produce any adverse effects on the potatoes. The anti-sprouting agent is eco-friendly and economically viable.