Glycine Betaine and Proline with Thinning Technique for Resistance Abiotic Stress of Cristalina Cactus Pear.

Cactus pear grows well in arid and semi-arid regions around the world. The area of cactus pear has expanded in the past few years in Egypt. This study was aimed to improve productivity and quality of Cristalina cactus pear under abiotic stress.In the present study, during the 2016 and 2017 seasons, 10-year-old cactus pear were thinned 2 weeks after fruit set at 6, 8 and 10 leaving approximately per cladode. Fruits were sprayed with glycine betaine (GB) and proline each at 5 mM 2 times: 2 weeks after fruit set and 2 weeks before harvest to protect abiotic stresses along with fruit thinning on cactus pear productivity and fruit quality at harvest and during cold storage for 30 days at 2±1°C with 90-95% RH.The results showed that thinning alone slightly increased the fruit yield. While, thinning with glycine betaine (GB) and proline substantially increased fruit weight, size, pulp weight, dry matter, acidity, TSS, color (h°), firmness, pulp pH, vitamin C and total phenols. Moreover, the applied treatments reduced weight loss, decay percentage and chilling injury index after 30 days of cold storage compared with control.The results of this study suggest that the highest productivity and the best fruit characteristics were obtained with application of glycine betaine and proline extract at 5 mM along with thinning at 6 fruits/mature cladode at harvest and after 30 days of cold storage and being suggested as natural alternatives to synthetic chemicals.