Yield and water relations of wheat under tillage systems and irrigation regimes at fayoum

Abstract EN

Two field experiments were conducted at Fayoum Agric.

Res.

Station (Kom Osheem) during 2002 / 2003 and 2003 / 2004 seasons to study the effect of tillage operations (number of ploughing) and irrigation at different levels of available soil moisture (ASMD), on yield, its components and some water relations of wheat crop (Giza 168 cv).

Three tillage operations, i.e., reduced till.

1, plouphing once to 20 cm depth (T1), reduced till.

2, plouphing twice to 20 cm depth (T2) and conventional till., (T3) were combined with three irrigation regimes, i.e., irrigation at 35 % ASMD (I1), at 55 % ASMD (I2) and at 75 % ASMD (I3), in a split- plot design with four replications.

The main results obtained were as follows: - Conventional tillage (T3) and irrigation at 35 % ASMD gave the highest averages of plant height, spike number / m2, 1000- grain weight, grain yield / fed.

and straw yield / fed.

in both seasons.

The lowest averages of yield and its components were obtained from using reduced till-1 (T1) and irrigation at 75 % ASMD (I3) in both seasons.

- Increasing tillage operation from T1 to T3 significantly increased grain and straw yields / fed.

and yield components in both seasons.

However, increasing the ASMD significantly decreased the yield and its components.

- Seasonal consumptive use (ETc) averaged 39.24 and 41.44 cm in 2002 /2003 and 2003 / 2004 seasons, respectively.

Increasing tillage from T1 to T3 and decreasing the ASMD from 75 % to 35 % ASMD increased the seasonal ETc from 33.78 and 36.66 cm to 44.52 and 46.76 in the two successive seasons.

- Monthly ETc rate increased gradually from Nov., to reach its maximum values during Mar.

and April.

Then declined till harvesting.

The crop coefficient (Kc) as an average of the two seasons during the growing season duration from Nov., to May were 0.53, 0.74, 0.87, 0.91, 0.99, 0.60 and 0.41, respectively.

- The highest water use efficiency values were 1.010 and 0.891Kg grains / m3 water consumed, resulted from using conventional tillage and irrigation at 35 % ASMD in both seasons.