Friday, June 8, 2018

teak -

Teak is a kind of high-quality wood production. Large trees, trunked straight, can grow to reach height 30-40 m. Large leafy, decaying in the dry season. Teak is known to the world by the name teak (English). This name is derived from the word thekku (തേക്ക്) in Malayalam, a language in Kerala state in southern India. The scientific name of teak is Tectona grandis L.f.

Teak can grow in areas with rainfall of 1 500 - 2 000 mm / year and temperatures of 27 - 36 ° C in both lowlands and highlands.  The best place for teak growth is the soil with a pH of 4.5 - 7 and is not flooded with water.  Teak has elliptical leaves that are wide and can reach 30 - 60 cm as adults.

Teak has slow growth with low germination (usually less than 50%) which makes the propagation process naturally difficult so it is not enough to cover the demand for teak. Teak is usually produced conventionally by using seeds. However, the production of seeds with large quantities in a certain time to be limited due to the outer layer of hard seeds.

Several alternatives have been made to overcome this layer such as soaking the seeds in water, heating the seeds over low heat or hot sand, and adding acid, base, or bacteria. However, these alternatives are still not optimal to produce teak in a fast and large amount.

Generally, teak that is in breeding process is susceptible to some diseases such as leaf spot disease caused by Phomopsis sp., Colletotrichum gloeosporioides, Alternaria sp., And Curvularia sp., Leaf rust caused by Olivea tectonea, and powdery mildew caused by Uncinula tectonae.

 Phomopsis sp. was the most infected, accounting for 95% of infected seeds in 1993-1994. The infection occurs in seeds aged 2 - 8 months. Characterization of this infection is the presence of brown necrosis on the leaf edge which then gradually spread to the midrib, infection then spread to the top of the leaves, petiol, and the end of the stem resulting in the leaf of the stem is drought. [5] If unconscious and uncontrolled, infection of Phomopsis sp. will spread to all the seeds so that the process of teak planting can not be done.