Potential of forage cactus pear accessions under saline water irrigation in arid areas

Abstract

Forage cactus pear has potential in arid areas of the world to be as one of the alternate fodders
in the existing forage/fodder production system. Thirty three cactus accessions introduced
under Arabian Peninsula Research Program of International Center for Agriculture Research
in the Dry Areas in Oman in 2005 with an objective to identify suitable species for the
rehabilitation of degraded rangelands in arid and saline areas were planted in randomized
complete block design under plant density of 40,000 ha-1 with three replications on a sandy
loam site under drip irrigation on December 2011 at Rumais Livestock Research Center in
Oman and evaluated annually during three consecutive years (2012 to 2014) following
standard agronomic practices recommended worldwide for cactus cultivation. The irrigation
water electrical conductivity was 5.37 dSm-1 at the beginning of the experiment while it was
6.01 dSm-1, 10.45 dSm-1 and 14.75 dSm-1, for the annual harvests on December 2012, 2013
and 2014, respectively. The observations on plant height (cm) at harvest, number of pads/plant,
weight/pad (kg) and green matter weight/plot were recorded at each harvest. The dry matter
weight was estimated based on dry matter percentage of green samples. Green and dry matter
yield/ha were estimated for their respective weights from experimental plots (3m x 3m). The
results revealed that the cactus accessions were different (p<0.05) with respect to all the
characters, such as plant height (45.75 to 82.00 cm), number of pads/plant (2.00 to 10.56),
weight/pad (0.32 to 0.59 kg), green matter yield (46.99 to 331.58 t ha-1), dry matter yield (4.40
to 33.38 t ha-1) and dry matter (8.29 to 13.00%). Ten cactus accessions had three-year fresh
annual fodder yield over 150 t ha-1. The accession No. 74112 from Mexico had significantly
highest (p<0.05) annual pad yield (331.58 t ha-1) of all other accessions studied. Other
accessions which were not different (p>0.05) but with important production were 4321 from
Tunisia (197.67 t ha-1), 75018 from Morocco (195.33 t ha-1), 68247 from Algeria (185.78 t ha-1),
73049 from Mexico (180.78 t ha-1) and 69241 from Tunisia (173.22 t ha-1). Results indicated
the potential of cactus for fodder production under saline water in arid conditions (from 5.37 to
14.75 dSm-1 during crop growth), with an average green fodder yield of 117.31 t ha-1 yr-1, as
compared with existing perennial Rhodes grass with an average of 80 to 100 t ha-1 yr-1. Hence,
these cactus accessions could be included in the existing fodder production system or used for                                                                                             afforestation of degraded rangelands of Oman besides the farms affected by salinity to the
extent of over 5.37 dSm-1.