Determination of the effects of leaf protein and calciumapplications on pre-harvest and fruit quality in karyagdı pear (Pyrus communis L.) cultivar

In pear production in Turkey, Antalya province ranks second after Bursa province. In the Mediterranean region, 80% of the pear production is produced in Antalya. Korkuteli district, on the other hand, ranks first among Antalya districts with an area of 41,570 ha in pear production and a production of 60.632 tons. However, it has been observed that the problems experienced in some orchards and varieties in pear cultivation in the Korkuteli region negatively affect the yield and quality in production. At the beginning of these problems is the pre-harvest castings that cause yield loss. Especially in some late pear cultivars, 'Karyağdı' pear cultivars have these castings more prominently. This variety, which has been grown in most regions of Turkey in recent years, has received a geographical indication with the name "Korkuteli Karyağdı Pear" in Korkuteli district. The 'Karyağdı' pear is a geographically marked variety that has increased in cultivation in many regions of Turkey in recent years. In this study, the effects of foliar protein and calcium (CaO) applications on the preharvest fall and fruit quality of the 'Karyağdı' pear variety grafted on quince seed were investigated. A mixture of 25% water-soluble calcium oxide (CaO) and 1% harpin protein was applied to the leaves at different times. As a result of the applications, phenological (bud swelling, bud burst, beginning of flowering, full bloom, end of flowering, harvest time) observations, pomological (fruit weight, fruit length, fruit width, fruit volume, fruit flesh firmness, starch test, fruit skin color, fruit meat color) measurements and chemical [water-soluble dry matter (WSC) amount, titratable acidity (TEA) amount, total phenolic content) analyzes were made. Flowering and harvest dates did not change significantly in 2019-2020. Applications were not effective on fruit weight, fruit volume, fruit width and length, fruit skin and fruit flesh color, TSSC, fruit flesh firmness. In May, June and July, the pre-harvest castings formed in CaO + Harpin applications were determined less than the control. While the highest fruit drop was obtained from the trees in the control group as 162.83 units, the lowest was obtained from the CaO + harpin protein mixture as 33.17 units. Therefore, it was concluded that CaO + harpin protein applications can be used to reduce pre-harvest spills in 'Karyağdı' pear cultivar.