Crop Load Regulation With Chemical Thinners in Deveci Pear (Pyrus Communis L.)

Abstract

The efficacy of three different doses of ammonium thiosulfate (ATS), potassium thiosulfate (KTS) and BA (6-benzyladenine) on fruit quality, yield and return bloom was evaluated in this present experiment on 'Deveci' pear (Pyrus communis, L.). All treatments were compared to an unsprayed control and hand fruit thinning. The highest fruit set was achieved with BA treatments. It was significantly reduced in KTS rates compared to control and other thinning treatments. KTS sprays create a statistically significant increase in fruit diameter and fruit weight, while ATS and BA have had no dramatic effect. Hand fruit thinning has resulted in heavier fruit at harvest similar to KTS with 2%. Thinners increased the percentage of fruit to 75 mm in diameter and proportions to 250-500 g fruit weight. In the control trees, the ratio of fruit to 75 mm diameter was 57%, the 75% or more of which was in hand thinning and chemical thinners. The proportion of fruits within 250-500 g fruit weight group was found in the highest KTS doses. No physiological disorder as bitter pit, water core, and aging disorder and phytotoxicity were observed in fruit samples. Study results show that 2% KTS significantly reduce crop load and increased fruit quality in 'Deveci' pear. Therefore, it can be used as an alternative to hand fruit thinning in the 'Deveci' pear to achieve high fruit quality. But, neither flower nor fruit thinners induced return bloom in 'Deveci' pear.

Fruit Yields Depend on Biomass and Nutrient Accumulations in New Shoots of Citrus Trees

“…Although the age and management of these citrus trees were similar, the yield variation among trees within each orchard was obvious (Figure 1). This phenomenon was also reported in other fruit crops such as pear, apple and olive [23][24][25]. The major reason for this could be related to the alternate bearing phenomenon [26], which is an important factor affecting the fluctuation of citrus production [27] that is higher in one season than in the next season [8].…”