These studies were carried out at the Experimental Farm of Rice Research and Training Center (RRTC), Sakha, Kafr El-Sheikh, Egypt, during 2007 and 2008 summer seasons. The purpose was to investigate the effect of irrigation intervals, cutoff irrigation and harvesting times on grain yield and its attributes as well as grain quality characters and water relations of Egyptian hybrid rice cultivar (EHR1). A split split–plot design, with four replicates, was used. The main plots were devoted to three irrigation intervals namely: continuous flooding (CF), irrigation every 6 (6D) and 12 days (12D). The sub-plots were assigned to five times for cut-off irrigation, i.e. cut-off irrigation after complete heading (ACH), 1-, 2-, 3and 4weeks after complete heading (WACH). However, the sub-sub plots were consisted of three harvesting times, i.e. harvest rice plants at 10-, 15and 20days after cut-off irrigation (DACI). The main results showed that grain yield and its attributes, as well as milling recovery and protein content, were significantly decreased as irrigation intervals increased from CF up to twelve days, but, unfilled grains (%) and amylose content were increased. Irrigation every six days came in between with insignificant difference with CF in most of previously mentions traits. Delayed cut-off irrigation up to 3and 4WACH significantly increased grain yield and most of its attributes, as well as grain quality. However, it reduced amylose content in 2007 and unfilled grains (%) in both seasons, as compared with cut-off irrigation ACH. Harvesting rice plants 10 and 15 DACI recorded the highest number of grains/panicle, panicle weight, 1000 grain weight and grain yield. However, the lowest values of milling recovery and protein content were recorded when plants were harvested at 10 DACI. Continuous flooding consumed the highest amount of irrigation water, while increasing irrigation intervals up to six and twelve days tended to decrease the amount of water used. Furthermore, 6D treatment recorded the highest water productivity (0.796 and 0.798 kg/m) and minimum grain yield reduction (4.54 and 3.64 %) with water saved about 8.04 and 7.08 %, compared to CF in both seasons, respectively. Delay cut-off irrigation recorded higher water productivity than early cutoff irrigation after complete heading. Generally, in case of water shortage, it was concluded to use irrigation every six days and cut-off irrigation 3-WACH with harvest plants 10 DACI for the highest water productivity and grain yield, as well as acceptable grain quality characters, of Egyptian hybrid rice cultivar (EHR1).
[1]
M. Hossain,et al.
Effect of Harvesting Time on the Milling and Physicochemical Properties of Aromatic Rice
,
2009
.
[2]
K. Z. Ahmed,et al.
Utilization of rice husk as an organic fertilizer to improve productivity and water use efficiency in rice fields.
,
2007
.
[3]
K. Z. Ahmed,et al.
Irrigation management and splitting of nitrogen application as affected on grain yield and water productivity of hybrid and inbred rice.
,
2007
.
[4]
B. Bouman,et al.
Nitrogen economy and water productivity of lowland rice under water-saving irrigation
,
2005
.
[5]
A. McClung,et al.
Effects of Drain and Harvest Dates on Rice Sensory and Physicochemical Properties
,
2005
.
[6]
H. Awad.
Rice production at the North of Delta region in GYPT as affected by irrigation intervals and nitrogen fertilizer levels
,
2002
.
[7]
B. Bouman,et al.
Field water management to save water and increase its productivity in irrigated lowland rice
,
2001
.
[8]
S. I. Bhuiyan,et al.
Producing more rice with less water from irrigated systems
,
1998
.
[9]
J. Lin.
Impact of hybrid rice on input demand and productivity
,
1994
.
[10]
Kenneth Helrick,et al.
Official methods of analysis
,
1990
.
[11]
B. O. Juliano,et al.
A simplified assay for milled-rice amylose
,
1971
.
[12]
A. Ghosh,et al.
Time of harvest for high head rice recovery.
,
1970
.
[13]
N. Philippou.
Effect of rice harvest time on milling yield and grain breakage
,
2022
.