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

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).