Studies the Effect of Alternative Dormancy Breaking Agents on “Le-Cont” Pear Cultivar

Abstract

This study was carried out during two successive seasons of 2013 and 2014, to investigate the effect of alternative dormancy breaking agents on bud break, growth, yield and fruit characteristics of "Le-Cont" pear cultivar. The following treatments were investigated at the dormant bud stage; 2% Garlic extract (GE) + 4% Summer oil; 4% GE + 4% (summer oil); 2% hydrogen cyanamide (H 2 CN 2) + 4% (summer oil); 4% H 2 CN 2 + 4% (summer oil); 2 % urea phosphite (CO(NH 2) 2 .H 3 PO 3) + 4% (summer oil); 4 % (urea phosphite) + 4% (summer oil); 4% Summer oil alone. The effects of all treatments were compared with the control (untreated trees). It is noticed that the beginning of flowering to all treatments resulted in early flowering and shorter than the control. All treatments increased both bud burst percentage and floral bud percentage; especially garlic extracts at the highest concentration. Garlic extract and urea phosphite concentration gave the highest number of fruits/tree and yield kg/tree also fruit weight, size and their dimensions have been affected. Hydrogen cyanamide 4 % and urea phosphite 2 % gave the softener fruits. In addition, all treatments was affected to increase TSS, total and reducing sugars than control treatment. Hormonal changes during the rest period in flower buds of Le-Conte pear were determined in the 2 nd season of the study. The highest levels of IAA and GA 3 contents were found to be in endo-dormancy (on the end of Feb.), while Abscisic acid showed the highest values during the 1 st deep dormancy (on the end of Dec.). It was a remarkable increases in IAA and GA 3 occurred at bud swelling stage. Meanwhile, the lowest level of ABA was observed at the same stage.

Plant Biostimulants Enhance Bud Break in Vitis vinifera Crimson Seedless Using Combination Treatments

“…It was notable that BB 3% had produced slightly better results than 1% H 2 O 2 . Indeed, mineral and vegetable oils have been reported to enhance bud-break properties in woody perennial crops, such as grapevine and pear; however, they generally have not produced results superior to HC treatment [49,59,60]. This is in harmony with current results for BB 3%.…”

“…The relevance of amino acid and nitrogen-salt-based agrochemicals that induce oxidative stress was also confirmed by the results recorded after SNH treatment. These products might be best applied with an adjuvant and/or dormancy oil to enhance uptake and performance in future studies [53,59,72]. Finally, in 2022, the complexity of field trials compared to controlled glasshouse conditions and the need for optimal timing of HC application were emphasized and require further exploration.…”

Plant Biostimulants Enhance Bud Break in Vitis vinifera Crimson Seedless

“…It was notable that BB 3% had produced slightly better results than 1% H2O2. Indeed, mineral and vegetable oils have been reported to enhance bud-break properties in woody perennial crops, such as grapevine and pear; however, they generally have not produced results superior to HC treatment [47,59,60]. This is in harmony with current results for BB 3%.…”

“…The relevance of amino acid and nitrogen-salt-based agrochemicals that induce oxidative stress was also confirmed by the results recorded after SNH treatment. These products might be best applied with an adjuvant and/or dormancy oil to enhance uptake and performance in future studies [51,59,72]. Finally, in 2022, the complexity of field trials compared to controlled glasshouse conditions and the need for optimal timing of HC application were emphasized and require further exploration.…”