اثرات زيرشكن زني و دورآبياري بر عملكرد سيب زميني

The effects of subsoiling and irrigation regime on potato yield

The effects of subsoiling and irrigation frequency on potato yield were evaluated during 2000-2001 growing season at Tajarak Research Station of Hamedan province. In this study, two tillage methods consisting of 1 )Conventional tillage using moldboard plow to a depth of 20-25 cm and 2) moldboard plowing + subsoiling to a depth of 35-40cm , and three irrigation frequencies (3,6 and 9 day irrigation intervals), were used. A split plot design within a randomized complete block design with three replications (tillage method and irrigation regime were assigned to main plot and sub plot, respectively) was used. The effect of subsoil loosening on soil resistance was evaluated by determining cone Index at two stages (after of the first and middle irrigation). At end of growth season (harvesting time), potato yield and some of the quantitative and qualitative factors of potato consisting of tuber size, tuber number per plant, tuber weight per plant and the perecentage of deformed tubers were measured. The result showed that subsoiling caused marginal reduction in soil strenght beneath the 25cm st.rface layer. No significent differences in yield were observed between subsoiled and unsubsoiled plots. The effect of irrigation regime on potato yield was significent (p<0.06) and 3-day irrigation interval treatment had higher yield than the other two irrigation treatments (6- and 9-day irrigation interval). The results indicated that irrigated crops such as potato for which water requirrnent is supplied in short intervals, it may not necessary to loosen the soil by subsoiling under conditions similar to this experiment.