Response of Soil Physical Properties and Crop Yield of Melon to Different Tillage Methods
Two-year field experiments were conducted to investigate the effect of different tillage methods on soil physical properties and crop yield of melon. Tillage treatments in the study were moldboard plow + two passes of disk harrow as conventional tillage (CT), two passes of disk harrow as reduced tillage (RT), one pass of disk harrow as minimum tillage (MT) and no-tillage (NT) as direct drilling method. The statistical results of the study indicated that tillage method significantly (P 0.05) affected crop yield, fruit weight, fruit length, fruit diameter, total soluble solids and root dry matter, but there was no significant differences in other components such as number of plants per hectare, number of fruits per plant and root length. The maximum value of crop yield (27.2 t ha ), number of plants per hectare (6360) and number of fruits per plant (1.9) was obtained in case 1 of CT treatment, while maximum value of fruit weight (3.6 kg), total soluble solids (10.25%), root length (42.3 cm) and root dry matter (72.5%) was observed in case of RT treatment. Also, maximum value of fruit length (29.0 cm) and fruit diameter (17.2 cm) was noted in case of MT treatment. Conversely, the minimum value of crop yield (20.6 t ha ), number of plants per hectare (5910), fruit weight (1.9 kg), fruit length (26.4 cm), fruit diameter 1 (14.1 cm), root length (36.6 cm) and root dry matter (54.1%) was obtained in case of NT treatment, while minimum value of number of fruits per plant (1.2) was observed in case of RT treatment. Moreover, minimum value of total soluble solids (9.75%) was noted in case of MT treatment. The statistical results of the study also indicated that tillage method significantly affected soil physical properties. The soil of the CT treatment had consistently the highest moisture contents (19.6%) and the lowest bulk density (1.41 g) and penetration resistance (560 kPa); while the soil of the NT treatment had the lowest moisture contents (16.8%) and the highest bulk density (1.52 g) and penetration resistance (1250 kPa). Therefore, moldboard plow followed by two passes of disk harrow was found to be more appropriate and profitable tillage method in improving soil physical properties and crop yield of melon due to reduced soil compaction, increased soil moisture content, enhanced seed-soil contact and suppressing weed growth.