Preliminary investigation on the response of spring barley ( Hordeum sativum) to soil cultivation with the ‘paraplow’

Abstract

In a long-term cultivation experiment on a sandy clay loam overlying magnesian limestone and cropped with spring barley ( Hordeum sativum) each year, mouldboard ploughing, shallow tine cultivation and direct drilling were compared. Compaction had become evident on the direct drilled treatment and to alleviate this the ‘Paraplow’, a slant-legged soil loosening implement, was used on all treatments to a depth of 35 cm in the autumn of 1980. A crop of spring barley (var. Athos) was grown in 1981, at a nitrogen fertiliser rate of 75 kg ha −1 N. Root growth, shoot dry matter, nitrogen uptake, grain yield and components of yield were recorded. Soil strength (by cone resistance) and dry bulk density of the soil were also measured. As a mean of all cultivation systems the ‘Paraplow’ increased grain yield by 12%. The response of the crop to cultivation by the ‘Paraplow’ was greatest on the mouldboard ploughed and long-term direct-drilled systems. The latter out-yielded the former, with shallow tine cultivation intermediate. The decrease in soil strength caused by the ‘Paraplow’ resulted in more rapid penetration of root axes and greater proliferation of roots in each horizon of the profile. There was no significant effect on shoot dry matter up to anthesis but, at harvest, barley on land treated with the ‘Paraplow’ had more ears with more grains per ear. Thousand-grain weight was not affected. The poorer growth of barley on ploughed than direct drilled land in 1981 was explained by temporary waterlogging of the soil in May.