Yarı-Kurak Koşullarda Damla Sulamada Farklı Sulama Aralıklarının Mısır Bitkisinin (Zea mays L. indentata) Su Verim İlişkilerine /The effect of different irrigation interval on water-yield relationship of corn (Zea Mays L. indentata) grown in semi-arid co

Abstract

OZET: Bu calisma; misir bitkisinde damla sulamada dort farkli sulama (2, 4, 6 ve 8 gun) araligindaki su verim iliskisini belirlemek ve verim tepki faktorunu (ky) saptamak amaciyla yapilmistir. Arastirma, 1998 ve 1999 yillarinda Harran Universitesi Ziraat Fakultesi arastirma ve uygulama alaninda tesaduf bloklari deneme desenine gore 3 tekerrurlu olarak yurutulmustur. Arastirmada, 1998 ve 1999 yillarinda sirasiyla 814-1116 ve 843-1206 mm arasinda sulama suyu uygulanmistir. 1998 ve 1999 yilinda en yuksek sulama suyu kullanim randimani (IWUE) 4 gunde bir sulanan konuda sirasiyla 1.43 ve 1.22 kg/m3 olarak belirlenmistir. Su kullanim randimani (WUE) her iki yilda ve tum konularda benzer sekilde (1.02 ve 1.13 kg/m3 arasinda) gerceklesmistir. Oransal bitki su eksilisi ile oransal verim dususu arasinda onemli farkliliklar saptanmistir. Denemenin her iki yilinda da en yuksek oransal su eksilisi 8 gunluk sulama konusunda (ID8) %29.6 ve %29.3, buna karsin ayni konuda yillara gore verimde oransal azalis %27.0 ve %28.4 olarak hesaplanmistir. Bu oranlar sulama araligi azaldikca dusmustur. Oransal evapotranspirasyon azalisi ile oransal verim azalisi arasinda verim tepki faktoru (ky) ilk yilda 0.72 – 0.95, ikinci yilda ise 0.70 - 0.97 arasinda hesaplanmistir. Her iki yilda da, sulama araliklarina gore dane verimleri istatistiksel olarak onemli (P<0.01) bulunmustur. Her iki yil icin de en yuksek verim, 4 gunluk sulama araliginda 1.41 ve 1.33 t/da saptanirken, en dusuk verim ise 8 gunluk sulama araliginda 1.03 ve 0.95 t/da olarak belirlenmistir. Arastirma sonuclarina gore yari-kurak iklim kusagindaki Harran Ovasinda, damla sulama yontemi ile 4 gunluk sulama araliginin misir bitkisi icin uygun oldugu saptanmistir. Anahtar kelimeler: Damla sulama, Sulama Araligi, Misir Bitkisi, Su-Verim Iliskisi The effect of different irrigation interval on water-yield relationship of corn (Zea Mays L. indentata) grown in semi-arid conditions ABSTRACT: This study was carried out to determine the effect of four different irrigation intervals (2, 4, 6 and 8 days) on water-yield relationship and yield response factor of corn crop grown in semi-arid conditions. The experiments were set based upon randomized block design with three replications and the experiments were conducted at the Research Station Field of Faculty of Agriculture in Harran University during 1998 and 1999. Total of 814-1116 and 843-1206 mm irrigation water was applied in 1998 and 1999, respectively. The maximum irrigation water use efficiency (IWUE) were determined from 4-day irrigation treatment group with 1.43 and 1.22 kg/m3 of IWUE in 1998 and 1999, respectively. Water use efficiency (WUE) of the treatment groups were found to be similar with values of 1.02 and 1.13 in both years. Significant differences were obtained between relative decrease of crop water use and relative decrease of yield. The maximum relative decrease of water was determined from 8-day irrigation treatment group (ID8) with 29.6 and 29.3% while 27.0 and 28.4% relative decrease of yield was obtained from the same treatment group in 1998 and 1999, respectively. These ratios were reduced as the the irrigation interval is decreased. The yield response factor (ky) between relative decrease of evapotranspiration and relative decrease of yield were ranged between 0.72 and 0.95 in 1998, between 0.70 and 0.97 in 1999. The grain yields based on irrigation intervals were found to be significantly important in both experimental years (P<0.01). The maximum yield were obtained from 4-day irrigation treatment group (ID4) with 1.41 and 1.33 t/da in both years while the minimum values were found in ID8 treatment group with 1.03 and 0.95 t/da. Results of this study demonstrated that 4-day irrigation interval was the optimal irrigation frequency for corn crop grown in semi-arid regions. Keywords: Drip irrigation, Irrigation interval, Corn, water-yield relationship.