Impact of tillage and mulching levels on the yield and yield components of wheat

A field experiment was conducted during Rabi season 2016 at Bacha Khan Agriculture Research Farm (BARF), Bacha Khan University Charsadda, using wheat variety Pir Sabak 2013. The experiment was laid out in RCB design having two factors i.e. tillage practices (cultivator using 1 time, 3 times, and 5 times) and mulching (M0-control, M1-wheat straw, and M2-sugarcane bagasse,). Tillage practices were applied to the main plots while mulching to the sub plots having 3 replications with a net plot size of 1.8m x 5m (9m) and row to row distance of 30 cm. Data were recorded for days to emergence, plant height, spike length, 1000-grain weight and grain yield. Results of the experiment showed that both tillage practice and mulching has significant effect on almost all the parameters. Tillage showed significant variation for all of the parameters recorded during the course of study except days to emergence. Maximum emergence (199 seedlings m), were attained by 1 time tillage application where maximum plant height (108 cm), maximum spike length (12 cm), maximum 1000-grain weight (45 g) and maximum grain yield (4717) were observed for 5 time tillage application. Similarly mulching application significantly affected all the parameters recorded during the course of experiment except days to emergence. Maximum plant height(110 cm), spike length (13 cm),1000-grain weight (44 g) and grain yield (5122 kg ha) were recorded for M1during the experiment. Overall, the combination of five times tillage and wheat mulching (M1) provide its superiority in term of yield i.e. 4717 kg ha and 5122 kg ha, respectively.


Introduction
Wheat (Triticum aestivum L.) belongs to the family Poaceae.It is the first grain crop around the world.In Pakistan wheat is used as a staple food because it provides daily dietary needs.Its production is generally for grain purpose, while in countries such as Argentina, Australia, Morocco, Syria and Uruguay, wheat crop is cultivated for grain as well as for fodder purpose and it leads from all other crops regarding area and production [1].Wheat plays a major role in the world food trade.In Pakistan wheat crop occupied about 8.9 million hectares area with total production of 25.21 million tones and average yield of 2833 kg ha -1 .While in Khyber Pakhtunkhwa, it occupied 0.72 million hectares area, the production was 1.15 million tones and the average yield was 1595 kg ha -1 during 2010-11 [2].It is an important food crop for Barani areas as well as for irrigated areas and plays a very important role in meeting the food requirements of both urban and rural population.It contributes 14.4 percent to agriculture and 3 percent to the gross domestic production (GDP) of Pakistan.Pakistan ranks in the top ten highly producing countries of wheat

Materials and methods
A field experiment was conducted to find out the impact of tillage practices and mulching on the yield and yield components of wheat.The experiment was conducted at Bacha Khan Agriculture Research farm (BARF) Charsadda.The experiment was laid out in factorial experiment with randomized complete block design having 9 treatments and 3 replications.Three tillage practices (Cultivator using 1 time, 3 times and 5 times followed by planking) and three mulching levels (control, wheat straw and sugarcane bagasse) were used.A net plot size of 1.8m x 5m (9m 2 ) was used having row to row distance of 30 cm.Data was collected on the following parameters.Days to emergence, Plant height, Spike length,1000-grain weight and Grain yield.

Result and discussion
Days to emergence Tillage, mulching and their combination showed non-significant effect on days to emergence of wheat (Table 1).However, plot ploughed by five times tillage shows more days to emergence 12 as compared to cultivator 1 times and 3 times tillage.Similarly more days (12) to emergence were taken by M0 and M2 as compared to M1.On days to emergence tillage and mulching showed non-significant effect this might be due the fact that at germination stage, the seedlings are mostly depends on stored food rather than on external environment.The result are in line with [18, 19] who reported that germination mostly depends on reserved food.2).Statistical analysis of the data revealed that tillage's and mulching had significant effect on plant height while the interaction had non-significant effect.Maximum plant height (108 cm) when plot treated with tillage cultivator 1 times and minimum 96 cm was observed.Among mulching maximum plant height 110 cm were recorded with wheat straw mulching as compared to other mulching practices.

Similar result was reported by [20].
Maximum plant height was recorded in plots where wheat straw was used as mulch, as compared to sugar cane and no mulch.

Spike length
Spike length as affected by tillage's and mulching data are presented in (Table 3).Statistical analysis of the data revealed that tillage's and mulching as well as T x M had significant effect on spike length of wheat.Lengthy spikes (12 cm) were produced when plot ploughed with cultivator 5 time as compared to one time and three time (10 cm) and (11cm).The results are in line with [22] who reported that increased in tillage intensities, increase spike length.Mulch material had significant effect on spike length.Maximum (13 cm) spike length was observed when wheat straw mulch was used as compared to sugar cane mulch.While no mulch and T x M result maximum (11cm) and minimum (7 cm) maintained.These results are in agreement with the investigations of [23].

Conclusions and recommendations
Based on results, it is concluded that Five times tillage followed by planking performed better and recommended for more grain yield in wheat.Wheat mulch performed better and is recommended for higher grain yield in wheat in the near future.

Authors' contributions
Similar finding was observed by [21].
Conceived and designed the experiments: M Ahmad, Performed the experiments: J Ali, Analyzed the data: G Ullah, Contributed reagents/ materials/ analysis tools: Z Hussain, Wrote the paper: M Ilyas & F Begum.
Mulches play a vital role for conserving the moisture in the soil profile for the success of wheat production, which totally depends on the precipitation received before and during crop growth period.Mulches reduce the evaporation losses.The practice of mulching has been widely used as a management tool in many parts of the world [12].However, the effect varies with soils, climate, and kind of mulch material used and the rate of application.The surface mulch favorably influences the soil moisture regime by controlling evaporation from the soil surface, improves infiltration, soil water retention, decreases bulk density and facilitates condensation of soil water at night due to temperature [12].

Table 2 . Plant height as effected by tillage's and mulching
LSD at P < 0.05 for tillage's = 6.29,LSD at P < 0.05 for mulching = 6.29

Table 5 . Grain yield as effected by tillage's and mulching
at P < 0.05 for tillage's = 153.6,LSD at P < 0.05 for mulching = 153.6Means followed by similar letters are significantly similar at p≤0.05 using LSD LSD