previous phase by Firoz Tughluq, who granted a series of concessions to
  the officers. Fixation of the estimated revenues of the iqtas was done
  permanently, thus allowing the muqtis to appropriate all the increases of
  revenue. The posts and the assignments were made practically hereditary.
  These changes, introduced by Firoz, were continued by all his successors.
      All the above developments in the iqta system were basically due to
  the changes in the composition of the nobility under the Delhi Sultans.
  The nobility was initially monopolised by the Turks, but gradually others
  like the Persians, Afghans, Abyssinians, and Indian Muslims, entered the
  nobility, thus making it more cosmopolitan and heterogeneous. The entry
  of new elements into the nobility under the Khaljis and early Tughluqs
  enabled the Sultans to increase their control over the iqta system, but once
  the new elements got themselves strengthened they demanded more
  powers and privileges, thus resulting in the liberalisation and
  decentralisation of the iqta system by Firoz Tughluq.
Improvement of Agriculture
The Sultans undertook efforts to enhance agricultural production by
providing irrigational facilities and by advancing takkavi loans for different
agricultural purposes. They also encouraged peasants to cultivate cash crops
instead of food crops, and superior crops (wheat) in place of inferior ones
(barley). There was an overall improvement in the quality of Indian fruits and
the system of gardening. Waste lands were granted to different people
thereby extending the cultivated area.
Growth of Urban Centres
The 13th and 14th centuries saw the rise and growth of several towns and
cities in India. For instance, Lahore    and Multan (modem Pakistan); Broach,