Rice Straw Mulch in Zero Tillage Wheat

Wheat is a cereal crop of immense importance to us, and the demand is fulfilled at the cost of soil poisoning and contamination through a number of pesticides, herbicides and excess of fertilizers. Zero tillage has become popular among the progressive farmers and serves as an economical method to conserve soil moisture, nutrients and labor force. Mulching on the other hand has benefits of conserving moisture in the field and others.

Adaptive Research Farms, Gujranwala, Pakistan have published a three year field experiment study to evaluate the possible merits of rice mulching in the zero tillage wheat fields. The outcome of the study are very promising and can be put to practical use. The research group evaluated that rice mulching in the field not only has its own merits but it also checks the weed growing in the field as well as improves the available phosphorus (P) and potassium (K) in the field.

The study was conducted over a period of 3 successive seasons (2008-2011) at the Adaptive Research Farms, Gujranwala in the field plots of 8 x 25 m size. The seed was planted by the common zero-till wheat drill having 15 cm row to row distance during the second week of November each season. The seeds were planted in the good moisture soil; NPK fertilizers were also applied. Nitrogen was applied in three doses. Manually harvest rice straw was chopped and applied in the treatments at 7.5, 10, 12.5, 15, 17.5 and 20.0 t/ha, the control group was without rice straw mulching. All other organic practices were performed and kept uniform in all treatments.

RESULTS

The outcomes of this study revealed that the rice mulching increased the available P and K in the plants and had no effect on the N; increase the soil organic matter significantly and lowered the pH of the soil. Minimum weed count (for both narrow and broad leaved weeds) was observed with the increasing amount of rice mulch; moreover, dry weed biomass also reduced. Population of wheat plants also decreased with increasing amount of rice straw mulch but number of tillers per m², grains per spike, 1000 grain weight and grain yield was significantly higher in the treated plots as compared to the control plot. Maximum grain yield (4.58 t/ha) was obtained for 15.0 t/ha treatment followed by 17.5 t/ha treatment. 

CONCLUSION

In the light of the above results, it can be concluded that rice straw can be used as an alternate in the integrated weed management program, as well as soil fertility supplement and bio-weedicide.