Bu çalışma yağmur koruyucu örtünün (RPC) Parka ve gibberellik asit (GA3)
uygulamaları ile birlikte hünnap meyvelerinin çatlama oranları ve kalite özellikleri
üzerine etkilerini araştırmak amacıyla yürütülmüştür. Örtü materyali, ticari hasat
tarihinden 5 hafta önce uygulanmıştır. % 1 Parka (% 7.5 stearik asit, % 5 selüloz ve
% 1 kalsiyum içerir) ve GA3 (15 mg L-1), ticari hasat tarihinden 2 ve 3 hafta önce
deneme ağaçlarına püskürtülmüştür. Kontrole kıyasla, tüm uygulamalardan (Parka,
GA3 ve GA3+Parka) daha düşük çatlama oranları elde edilmiştir. Çatlama oranları
örtülü ağaçlarda, örtüsüz ağaçlardan daha düşük çıkmıştır. Bununla birlikte,
GA3+Parka ile muamele edilmiş meyvelerden, hem kontrol hem de diğer
muamelelere kıyasla daha düşük çatlama oranı tespit edilmiştir. GA3 ile muamele
edilmiş meyvelerden ağırlık, genişlik, hue açısı ve sertlik değeri bakımından
kontrole kıyasla daha yüksek, ancak L* değeri bakımından daha düşük değerler
ölçülmüştür. Kontrolle karşılaştırıldığında, tüm uygulamalardan önemli derecede
daha düşük bir solunum hızı ve suda çözünür kuru madde içeriği elde edilmiştir.
Fakat titre edilebilir asitlik, C vitamini ve toplam fenolik bileşikler bakımından ise
daha yüksek değerler belirlenmiştir. Yağmur koruyucu örtü altındaki meyvelerden,
açıktaki meyvelere kıyasla önemli derecede daha yüksek hue açısı, solunum hızı, C
vitamin, toplam fenolik bileşikler, toplam flavonoid ve antioksidan aktivitesi (hem
DPPH hem de FRAP) elde edilmiştir. Sonuç olarak hünnap meyvesinde meydana
gelen çatlamayı azaltmak için, diğer kalite özelliklerini olumsuz etkilemeksizin,
örtü uygulamasının önemli bir araç olarak kullanılabileceği belirlenmiştir. Aynı
zamanda, Parka ve GA3 uygulamalarının çatlamayı önemli düzeyde azalttığı, bu
azalış üzerine kombine uygulamanın daha da etkili olduğu tespit edilmiştir.,This study was carried out to investigate the effects of rain protective covering
(RPC) together with Parka and gibberellic acid (GA3) treatments on cracking rates
and quality attributes of jujube fruits. RPC was mounted 5 weeks before the
commercial harvest date. 1% Parka (containing 7.5% stearic acid, 5% cellulose and
1% calcium) and GA3 (15 mg L-1) were sprayed to experimental trees 3 and 2 weeks
before the commercial harvest date. As compared to the control, all treatments
(Parka, GA3 and GA3+Parka) yielded lower cracking rates. Cracking rates were also
significantly lower in covered trees than in uncovered trees. However, GA3+Parka
treated fruit had significantly lower cracking rates than both the control and the
other treatments. As compared to the control, all treatments yielded a significantly
lower respiration rate and soluble solids content, but higher titratable acidity,
vitamin C and total phenolics. The covered fruits had significantly higher hue angle,
respiration rate, vitamin C, total phenolics, total flavonoids and antioxidant activity
(free radical scavenging activity on DPPH and FRAP) than the uncovered ones. It
was concluded based on the present findings that rain-protective covering could be
used as an efficient tool to reduce cracking rates in jujube fruits without any
negative effects on the other quality attributes. It was also concluded that Parka and
GA3 treatments reduced cracking rates significantly and such a reduction was more
remarkable with combined GA3+Parka treatments.
This study was carried out to investigate the effects of rain protective covering
(RPC) together with Parka and gibberellic acid (GA3) treatments on cracking rates
and quality attributes of jujube fruits. RPC was mounted 5 weeks before the
commercial harvest date. 1% Parka (containing 7.5% stearic acid, 5% cellulose and
1% calcium) and GA3 (15 mg L-1) were sprayed to experimental trees 3 and 2 weeks
before the commercial harvest date. As compared to the control, all treatments
(Parka, GA3 and GA3+Parka) yielded lower cracking rates. Cracking rates were also
significantly lower in covered trees than in uncovered trees. However, GA3+Parka
treated fruit had significantly lower cracking rates than both the control and the
other treatments. As compared to the control, all treatments yielded a significantly
lower respiration rate and soluble solids content, but higher titratable acidity,
vitamin C and total phenolics. The covered fruits had significantly higher hue angle,
respiration rate, vitamin C, total phenolics, total flavonoids and antioxidant activity
(free radical scavenging activity on DPPH and FRAP) than the uncovered ones. It
was concluded based on the present findings that rain-protective covering could be
used as an efficient tool to reduce cracking rates in jujube fruits without any
negative effects on the other quality attributes. It was also concluded that Parka and
GA3 treatments reduced cracking rates significantly and such a reduction was more
remarkable with combined GA3+Parka treatments.
