Organik parselde uzun yıllık ekim nöbeti deseni oluşturulmasına yönelik planlanan bu çalışmada, ön bitki olarak yetiştirilen brokoli, bakla, fiğ ve nadas (= doğal vejetasyon) parsellerinde yapılan sakız kabağı üretimindeki verim ve kalite değişimlerinin belirlenmesi amaçlanmıştır.Çalışma, E.Ü. Ziraat Fakültesi Bahçe Bitkileri Bölümünde 7 yıldan beri sürdürülen `Organik Üretim` alanında yürütülmüştür. Çalışmanın ana bitki materyalini Sakız kabağı, ön bitki materyallerini de Monopoly (F1) brokoli, Sevilla bakla ve adi fiğ çeşitleri oluşturmuştur. Çalışmada, Organik Tarım Esasları ve Uygulanmasına İlişkin Yönetmelikte yer alan `Bitki Koruma ve Bitki Besleme maddelerinden` yararlanılmıştır. Brokoli ön bitki parsellerinde hasat olumuna gelen brokoli başları hasat edilerek birim alan verim değeri ile bazı kalite özellikleri belirlenmiştir. Ön bitki parsellerindeki bitkiler toprağa karıştırıldıktan sonra aynı parsellerde yapılan sakız kabağı üretiminde de ön bitki ve gübreleme parsellerine göre birim alan verim değerleri ile bazı kalite özellikleri saptanmıştır.Çalışmada brokoli ön bitki parselinde bir önceki sezon yapılan gübreleme uygulamasına bağlı olarak daha yüksek toplam verim (2517 kg/da) elde edilmiştir. Buna karşılık baş kalitesinde önemli bir değişim gözlenmemiştir. Ön bitki üretiminden sonra da birim alana en fazla yaş ot miktarının da brokoli parselinden (4382 kg/da) sağlandığı belirlenmiştir. Buna karşılık ön bitkilerden sonra yetiştirilen kabak üretiminde ise en yüksek verim fiğ ön bitki parselinden elde edilmiştir. Gübreli fiğ parselindeki 2308 kg /da sofralık kabak verimi gübresiz fiğ parselinde 2379 kg/da bulunmuştur. Kabak üretiminde en yüksek verim değerlendirmesi açısından fiğ parselini de brokoli parselinin izlediği saptanmıştır. Ortalama meyve ağırlığı, meyve boyu ve meyve kuru ağırlık oranının da gübre uygulaması ile iyileştiği, buna karşılık meyve çapı ve meyve renk değerlerinin ise bu uygulamadan etkilenmediği ortaya konmuştur. Çalışmada en yüksek orandaki yabancı ot miktarı da fiğ ön bitki parselinde belirlenirken genelde az oranda ot da bakla ve brokoli parsellerinde saptanmıştır. Anahtar sözcükler: organik tarım, sakız bak, ön bitki, verim, kalite.

This study was designed to test the effects of different pre-crops including broccoli (Brassica oleracea cv. Italica), faba bean (Vicia faba), common vetch (Vicia sativa) and fallow (natural vegetation) applications on marrow squash (Cucurbita pepo) yield and quality.The experiment conducted in `organic production` field at E.U. Faculty of Agriculture Department of Horticulture Production Field for 7 years. The plant materials in the experiment are marrow squash as main crop and the pre-crops are monopoly (F1) broccoli, Sevilla faba bean cultivars and common vetch. In the study using `plant protection and plant nutrition substances` related to organic agriculture principles and applications as information resource. The pre-crop Broccoli heads were harvested and yield per unit area value and some quality characteristics are determined. All pre-crop plot plants were mixed with the soil, after that in the marrow squash protection according to pre-crop and fertilized plots yield per unit area value and some quality characteristics were determined. The pre-crop Broccoli heads were harvested and yield per unit area value and some quality characteristics are determined. Depending on the work done on previous season fertilizer application from pre-crop broccoli plot Higher total yield (2517 kg / ha) of broccoli were obtained. In contrast, no significant change was observed in broccoli fruit quality. After pre-crop production at the maximum amount of wet weed plants broccoli pre-crop plot had provided (4382 kg / ha) per unit area of the parcel. In contrast, after the pre-crop grown in marrow squash production and the highest yield was obtained from pre-crop common vetch plant plot. While the fertilized common vetch plot gave (2308 kg/da) for the edible marrow squash yield on the other side and from the non-fertilized common vetch plot was (2379 kg/da).The highest yield in the marrow squash production was obtained from common vetch plot followed by broccoli plot. The average fruit weight, fruit size and fruit dry weight ratio values was improved by fertilized plots application whereas, fruit diameter and fruit color values It has not been demonstrated to affect from the same plots. In this context, while the highest amount of wild weed was on the common vetch plot the opposite was in the faba bean and broccoli plots. Keywords: marrow squash, organic, broccoli, crop rotation, yield quality, weed.This study was designed to test the effects of different pre-crops including broccoli (Brassica oleracea cv. Italica), faba bean (Vicia faba), common vetch (Vicia sativa) and fallow (natural vegetation) applications on marrow squash (Cucurbita pepo) yield and quality.The experiment conducted in `organic production` field at E.U. Faculty of Agriculture Department of Horticulture Production Field for 7 years. The plant materials in the experiment are marrow squash as main crop and the pre-crops are monopoly (F1) broccoli, Sevilla faba bean cultivars and common vetch. In the study using `plant protection and plant nutrition substances` related to organic agriculture principles and applications as information resource. The pre-crop Broccoli heads were harvested and yield per unit area value and some quality characteristics are determined. All pre-crop plot plants were mixed with the soil, after that in the marrow squash protection according to pre-crop and fertilized plots yield per unit area value and some quality characteristics were determined. The pre-crop Broccoli heads were harvested and yield per unit area value and some quality characteristics are determined. Depending on the work done on previous season fertilizer application from pre-crop broccoli plot Higher total yield (2517 kg / ha) of broccoli were obtained. In contrast, no significant change was observed in broccoli fruit quality. After pre-crop production at the maximum amount of wet weed plants broccoli pre-crop plot had provided (4382 kg / ha) per unit area of the parcel. In contrast, after the pre-crop grown in marrow squash production and the highest yield was obtained from pre-crop common vetch plant plot. While the fertilized common vetch plot gave (2308 kg/da) for the edible marrow squash yield on the other side and from the non-fertilized common vetch plot was (2379 kg/da).The highest yield in the marrow squash production was obtained from common vetch plot followed by broccoli plot. The average fruit weight, fruit size and fruit dry weight ratio values was improved by fertilized plots application whereas, fruit diameter and fruit color values It has not been demonstrated to affect from the same plots. In this context, while the highest amount of wild weed was on the common vetch plot the opposite was in the faba bean and broccoli plots. Keywords: marrow squash, organic, broccoli, crop rotation, yield quality, weed.