Effect of drip deficit irrigation and soil mulching on growth of common bean plant, water use efficiency and soil salinity

The present investigation aimed at assessing the effect of two mulching materials (Rice straw mulch (RSM) and Farmyard manure mulch (FYM)), three irrigation treatments (I-100% = 100%, I-85% = 85% and I-70% = 70%) of crop evapotranspiration (ETc) and four mulch layer thicknesses (MLT0, 3, 6 and (9) cm) on common bean yield, its components, water use efficiency and soil salinity under drip irrigation. Results obtained showed that the maximum values of bean yield were obtained under FYM compared to RSM. The greatest values dry seed yield of bean were obtained with the no-deficit treatment (Moor) while the lowest ones were observed in I-70% treatment. The average bean yield value of MLT9 was increased by 9.67, 25.28 and 45.80% than those of MLT6,3 and (0), respectively. The lowest value of soil salinity was obtained under (I-100%), while the greatest one was obtained from (I-70%). The highest soil salinity value was observed under MLT0 (no mulch) compared to another treatments. The average EC value for treatment MLT0 was increased by12.80, 18.86 and 28.75% than those of MLT3, 6 and (9), respectively. Under environmental conditions of the study area, the treatment (I-100% x FYM x MLT9) proved to be the most suitable for producing high bean crop. Under limited irrigation water, application of (I-85% x FYM x MLT9) treatment was found to be favorable to save 15% of the applied irrigation water with no reduction in bean crop.