ABSTRACT:To break dormancy and increase the germination of Prunus avium L. (mazzard cherry) seeds, various methods were tested including the removal of the seed coat after cold moist stratification and treatment with GA 3 , KNO 3 , or thiourea. Treatments with 7,500 ppm KNO 3 after 120 days of stratification were more effective, yielding 64.54% germination of seeds with coat. In seeds without coat, 500 ppm GA 3 treatment after 120 days of stratification gave 79.74% germination; a value increased about 29% compared to control.

No abstract

No abstract

The important role of aminoethoxyvinylglycine (AVG) pre-harvest application in fruit harvest time, fruit quality and mineral element contents of 'Akça' (Pyrus communis L.

Williams' is the highly quality pear cultivar mostly produced in the Eğirdir region of Turkey. ReTain (15% aminoethoxyvinilglycine, AVG) is a plant growth regulator used to control pre-harvest drop and increase fruit weight and firmness. The objective of this study was to determine the responses of AVG treatments on the preharvest drop and fruit quality of 'Williams' pear. Pear trees of the cultivar 'Williams' were sprayed 30, 21 and 7 days before commercial harvest (DBH) with AVG, at doses of 100, 125 and 150 mg L-1 , and assessed for pre-harvest drop, yield, maturity, delay in harvest, fruit quality, ethylene production and respiration rate at the harvest time. Fruit samples were analyzed for fruit quality parameters which are: fruit width, fruit weight, soluble solids content (SSC), titratable acidity (TA), fruit firmness, fruit colour, fruit macro and micro elements content. Maturation of the 30 and 21 DBH AVG-treated fruits were delayed 3-4 days compared to the 7 DBH AVG-treated and control groups. The pre-harvest drop decreased with all AVG applications by approximately 38-100% in comparison with the control group fruits. AVG treatments increased fruit size (7-10%), fruit weight (26-41%) and fruit firmness (2-16%) of 'Williams' pear. AVG application reduce ethylene production and respiration rate and it was found that the applications enhance the ethylene production and respiration rate by approximately (100%) compared to the control fruits on the harvest date. Results of this study indicated that 30 DBH and 21 DBH AVG-treatments at 100 mg L-1 can be recommended for 'Williams' pear cultivar on both pre-harvest fruit drop, as well as in harvest date and fruit quality.

No abstract

Prohexadione-calcium (Pro-Ca) is a recently developed plant growth retardant used in some fruit trees. However, it is important that the reduction of vegetative shoot growth does not decrease yield and fruit quality. In this study, the effects of Pro-Ca applications on the vegetative growth and some fruit quality of the Monroe peach, growing on vigor rootstock (GF 677) were investigated. For this reason, trees were sprayed twice with 0 (water + surfactant), 62.5, 125, 250 g 100 L -1 water Pro-Ca in the annual shoots reached 5 cm within a three week interval in the spring of 2018 and 2019 years. Shoot length was decreased by 28-32% for shoots treated with Pro-Ca. The average internode length was significantly reduced for Pro-Ca-treated shoots. The lowest average internode length on the shoot was obtained with 125 and 250 g 100 L -1 . The effects on fruit quality were positive in this study. Application of Pro-Ca (125 and 250 g 100 L -1 ) increased the fruit size and fruit mass of cv. Monroe' peach. 250 g 100 L -1 Pro-Ca concentration led to firmer fruit relative to the other applications and control fruits. Two application 125 or 250 g 100 L -1 Pro-Ca applications were found more effective considering the criteria investigated. The Pro-Ca applications were found to be effective in controlling the vegetative shoot growth and fruit quality in cv. Monroe/GF-677 peach.

No abstract