Loss of genetic diversity is probably one of the major reasons for Dalbergia sissoo and Juniperus excelsa polycarpus dieback problem in Pakistan

Background/Question/Methods

Ziarat Juniper Forest is Biosphere reserves recognized under the United Nations Education, Science and Cultural Organization's (UNESCO's) Man and the Biosphere Program. The biosphere reserve is home to the largest area of juniper forest (juniperus excelsa polycarpus) in Pakistan, covering about 110 000 ha. It is believed that the forest is the second largest of its kind in the world.  Pakistan has more than 100,000 ha of Dalbergia sissoo plantation out of 4.5 million ha or 4.0% of the total land area of 87.98 million ha under forest, which is round 2.2% of total forest. The farm lands of Punjab have about 200 million trees of which 90% are in irrigated areas. The tree per hectare is 16.9 for all areas: 18.7% in irrigated areas and 6.2% in un-irrigated areas. Shisham (Dalbergia sissoo) 42%, Phulai (Acacia modesta) 20%, Kikar (Acacia nilotica) 11%, Bakain (Melia azadirachta) 7% and Ber (Zizypus muritiana) 3.1% are the predominant species along with other species in un-irrigated areas

Results/Conclusions

Both of these important and vital plant species are dying because of dieback thought to be because of Macro/micro nutrient deficiency ,Soil/water induced physiological stresses, Soil pH, Physically inflicted stresses (lopping, debarking, etc), Ecological stresses, Insect borer attack and Fungus attack. Millions have been spent for this diagnose and remedy but this study believes that all money wasted because major problem of this disease was loss of genetic diversity which suppressed the immunity of these trees and Pakistan is losing its these important forest trees. In this study the various samples of Dalbergia sissoo collected from all over the country and different samples of Juniperus excelsa polycarpus  were collected from Ziarat forest and also the samples of Acacia modesta collected from all over the country and SSR marker-based molecular characterization and genetic diversity analyzed. The results were as expected the loss of genetic diversity was observed in both the  Dalbergia sissoo and Juniperus excelsa polycarpus  while significantly high diversity was found in Acacia modesta population of Pakistan which is not facing any such disease threat