Alterations in Selected Pomological and Biochemical Characteristics of Fruits from Certain Pear Genotypes Under Changing Climatic Conditions

Abstract

Under prevailing environmental conditions, stressors such as drought and climate change have emerged as significant factors impacting agricultural productivity and crop quality. To investigate this phenomenon, ten distinct pear genotypes were classified into astringent (A) and non-astringent (N) categories based on their inherent astringency levels. Pomological and biochemical characteristics of the genotypes were systematically analyzed. A comparative statistical analysis was performed on mean values of pomological traits (fruit width, length, weight, upper/lower surface coloration, firmness), peel color parameters (L*, a*, b*, chroma [C*], hue angle [°h]), soluble solid content (SSC), pH, titratable acidity (TA), vitamin C concentration, total phenolic content, and antioxidant capacity between the two groups. Genotypes exhibiting elevated a* values in lower peel coloration and higher L*, b*, and °h values in upper peel coloration were categorized as non-astringent (N). Conversely, genotypes with increased °h values in lower peel coloration and elevated a* values in upper peel coloration were classified as astringent (A). Biochemical analyses revealed significantly higher SSC in astringent genotypes, whereas non-astringent genotypes demonstrated greater pH levels. Mean TA and vitamin C concentrations were statistically higher in astringent genotypes compared to non-astringent counterparts. However, total phenolic content and antioxidant capacity showed no statistically significant intergroup differences.

Keywords

• Pear
• Genotype
• Stress Conditions
• Pyrus communis

Bazı Armut Genotiplerine Ait Meyvelerde Değişen İklim Koşullarında Bazı Pomolojik ve Biyokimyasal Özelliklerin Değişimi

Abstract

Günümüz koşullarında, kuraklık, iklim değişikliği vb. şartlar üretimi ve ürün kalitesini ciddi bir şekilde etkilemeye başlamıştır. Bu durumu ortaya koymak amacıyla, farklı 10 farklı armut genotipi, burukluk durumuna göre, buruk olan (B) genotipler ve buruk olmayan (D) genotipler olarak gruplandırılmıştır. Genotiplerin pomolojik ve biyokimyasal ölçümleri değerlendirilmiştir. Buruk (B) ve buruk olmayan (D) genotiplerin (en, boy, ağırlık, alt ve üst renk, sertlik), meyve üst ve alt kabuk renk ölçümleri (L, a, b, C ve h°), suda çözünür kuru madde (SÇKM), pH, titre edilebilir asitlik (TEA), C vitamini, fenolik madde içeriği ve antioksidan kapasite değerlerinin ortalaması gruplar arasında istatistiksel olarak karşılaştırılmıştır. Kabuk alt renk a, kabuk üst renk L, b ve °h değerlerinin yüksek olduğu genotipler buruk olmayan (D) genotipler iken, kabuk alt renk °h, kabuk üst renk a değerlerinin yüksek olduğu genotipler buruk olan (B) genotipler olmuştur. Biyokimyasal ölçümler sonucunda belirlenen SÇKM değeri, buruk genotiplerde istatistiksel olarak yüksek, pH değeri ise buruk olmayan genotiplerde yüksek bulunmuştur. Titre edilebilir asitlik (TEA) ve C vitamini ortalama değerleri, buruk genotiplerde istatistiksel bakımdan buruk olmayanlara göre yüksek olmuştur. Toplam fenol ve antioksidan kapasite ise gruplar arasında istatistiksel olarak önemli bir fark oluşturmamıştır.

Keywords

• Armut
• Genotip
• Stres Faktörleri
• Pyrus communis

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