Tories accused the Government of presiding over a continuing decline in agriculture and rural services.
Lords spokeswoman Baroness Byford was speaking during second reading debate on the Natural Environment and Rural Communities Bill.
She said the Bill followed four years of pressure on Defra and its associated bodies.
And although on the surface it was the outcome of a report by Labour peer Lord Haskins, it had to be remembered "his work was occasioned by at that time - poor performance levels on behalf of Defra.
" There was a sluggish response to the outbreak of foot-and- mouth disease, there was a lack of control over subsequent events and I believe there are still some outstanding bills to be paid - the problems that also followed the amalgamation of the cattle tracing service and the Rural Payments Agency, the appalling number of errors consequent on the introduction of satellite mapping on farms and the constant evidence of the decline in British agriculture and the closure of rural services. Growth of rural poverty and deprivation is still with us," said Lady Byford.
The legislation, which has already been debated by MPs --creates a single organisation, Natural England to manage the natural environment. It will also be responsible for issues of access, recreation and quality of life.
The Government says this would establish a powerful champion for landscape and conservation working for people, places and nature.
Earlier the Government said social, economic and environmental issues will all be taken into account when shaping policy.
Defra Minister Lord Bach said economic prosperity underpinned the provision of good public services and the Bill would create "simpler, stronger organisational structures and transform the way we deliver rural and environmental services."