Bafra Valley (Turkey)
The CS-7 experiment was conducted at the experimental farm of the Black Sea Agricultural Research Institute at Bafra Valley of Samsun province at rice growing season in 2019. Soil of the experimental site was found to be clay-sandy.
The experimental plots (5×5 m) was carried out with randomized complete block design combining two rice varieties of rice (Rekor CL and Osmancık-97 ) and six irrigation treatments that were replicated thrice. The plots was performed six water treatments. Continuous flooding method (CF), Alternate Wetting and Drying method (AWDS5, AWDS10, AWD15) and Drip irrigation method (Drip irrigation 1,75 XEpan, Drip irrigation 2 X Epan) was be applied in the experiment. We installed polythene sheets down to 100 cm between CF and AWD to prevent seepage and water flow between the plots. In AWD plots, PVC pipes of 10 cm in diameter and 35 cm in length were installed in the field keeping 10 cm above the soil and the remaining 25 cm which was perforated underneath to measure the depletion of soil water in the field. Irrigation water was applied when depleting water table inside the pipe reached a certain level (AWD 5-10-15). In the drip irrigation treatments, water was given on alternate days on the basis of pan evaporation values of the previous two days. In CF, AWD and Dirip irrigation, seeds were sown in seed beds on May 24 and 21-d-old seedlings were manually transplanted at three seedling per hill at a spacing of 20 cm× 20 cm on 15 July. In CF and AWD water treatments, the water level 30-50 mm was keeped during first 14 days to promote better seedling establishment and to improve weed control. Afterwards, the ponded water layer in CF was kept between 50 mm until 15 days before the harvest. In AWD treatments , Irrigation water was applied until 50 mm level on the plots when depleting water table inside the pipe reached a certain level. At around flowering all AWD treatments were suspended and water depth was maintained 50 mm depth to reduce the risk of spikelet sterility due to water-deficit stress at this sensitive stage. After completion of the flowering stage, AWD was applied again until 2 weeks before the expected time of harvest in all water treatments.
The dirip irrigation treatments soil was kept saturated for the first 14 days. ; thereafter, the irrigation treatments began. In the drip irrigation treatments, water was given on alternate days on the basis of pan evaporation values of the previous two days until 2 weeks before the expected time of harvest.
Fertilizer management protocols were same at all the water treatments. a total of 90 kg ha-1 of nitrogen (N) was applied in three equal splits: (1) Diammonium phosphate before transplanting, and Amonyum sulfat at mid-tillering and panicle initiation. Phosphorous (P) and potassium (K) were also applied as basal fertilizer at 40 kg each ha-1. Weed control was maked manually in the all water treatments.The daily maximum temperature, daily minimum temperature, average temperature, sunshine duration,solar radiation, average humidity and daily precipitation data was be obtained from the meteorological station next to the experimental area. The amount of irrigation water given to each plots was be measured using water meter. Daily standing water depths (aboveground) and perched water depths (below ground) in all AWD plots was also monitored manually by measuring the water inside the field water tubes. In CF plots, wooden stick gages was monitored to monitor daily ponded water depths. Soil moisture tension at 15-cm soil depth was monitored using tensiometers installed on AWD plots and the drip irrigation plots. In CF and AWD, leaf water potential was be taken at effective tillering panicle differentiation, flowering of rice.
In this study, Morphological and physiological observation was taken according to Standard Evaluation System (SES) be used to assessing rice agronomic performance and classifying rice responses to biotic and abiotic stresses at published in IRRI. Time of heading (number of days from seeding to 50% flowering), Physiological maturity (PM), Plant Height (cm), Panicle Length (PnL ), Panicle number (m2), Spiklet number per panicle, Spikelet Fertility (SpFert), 1000 grains weight (g), Percentage of filled grain (%), Grain Yield (Yld)
We will have investigate emissions of methane CH4 and N2O under alternate wetting and drying methods and continuous flooding methods in 2020 rice growing seasons. Gas sampling will conduct simultaneously at three points for CF and AWD 15 treatments plots once a week with additional daily sampling for 5 days after fertilizer application. Gas samples will collected at 0, 15 and 30 min after the chamber deployment between 9:00–11:00 am.