An improved and simplified somatic embryogenesis protocol in Chir pine (Pinus roxburghii)

Area of Science:

• Forestry
• Plant Biotechnology
• Conservation Biology

Background:

• Forests are crucial for bioeconomy but face global depletion.
• Pinus roxburghii holds significant ecological and economic value for Pakistan.
• This species is vital for climate change adaptation through afforestation and reforestation.

Purpose of the Study:

• To develop an improved protocol for somatic embryogenesis in Pinus roxburghii.
• To document the developmental stages of zygotic and somatic embryos for this species.
• To optimize media formulations for enhanced initiation, proliferation, maturation, and conversion of somatic embryos.

Main Methods:

• Initiation of somatic embryogenesis using immature pre-cotyledonary zygotic embryos on specific media (LP-889).
• Proliferation and maintenance of embryogenic tissue using optimized media (LP-1250) with plant growth regulators.
• Maturation of somatic embryos tested on two media (mLV and LP-1562) with varying L-glutamine and abscisic acid (ABA) concentrations.

Main Results:

• Somatic embryogenesis initiation was influenced by zygotic embryo developmental stage.
• LP-1562 medium yielded a higher number of somatic embryos (310/g) compared to mLV medium (204/g).
• Successful conversion of somatic embryos was achieved, but low rooting rates and precocious germination remain challenges.

Conclusions:

• The study presents a significantly improved protocol for Pinus roxburghii somatic embryogenesis.
• The findings provide a basis for mass propagation of this ecologically and economically important pine species.
• Further research is needed to address rooting and precocious germination issues for successful ex-situ conservation and reforestation.