TY  - JOUR
TI  - Determination of Irrigation Time Using Plant Water Stress Index Values of
Second Crop Sunflower in Semi-Arid Climate Conditions
AB  - This study was carried out in 2020 to determine crop water stress index (CWSI) by using infrared
thermometer (IRT) data calculated by leaf canopy temperature measurements of the second crop
sunflower genotype in semi-arid climate conditions, and to determine the relationships between
irrigation time, seed yield of sunflower plant and CWSI by using these index values. Irrigation
program consisted of a full irrigation and 2 different levels of stress, which were 100% (I100), 70%
(I70), 35% (I35) of water losses within the effective root depth of 90 cm every 7 days. A total of
644 mm of irrigation water was applied to I100 (control) irrigation. The water consumption for full
irrigation was 721 mm and the yield was 3516.00 kg/ha. Lower limit (LL) value without water
stress required to determine plant water stress index was Tc-Ta=-2.528×VPD +0.749 (R2=0.814)
and upper limit (UL) value, where the plant is completely under water stress, was determined as
+3.27°C. Crop water stress index value threshold at which sunflower seed yield started to decrease
was calculated as 0.33 using the infrared thermometer measurements at the time of irrigation. In
addition, a negative correlation was obtained between sunflower seed yield and CWSI values. The
results revealed that the yield tends to decrease as the CWSI increases
AU  - SEÇME, HALİS
AU  - ucak, ali beyhan
DO  - 10.24925/turjaf.v9i12.2289-2295.4641
PY  - 2021
JO  - Türk Tarım - Gıda Bilim ve Teknoloji dergisi
VL  - 9
IS  - 12
SN  - 2148-127X
SP  - 2289
EP  - 2295
DB  - TRDizin
UR  - http://search/yayin/detay/511421
ER  -