Arabica coffee is a small tree in its original habitat but grows like a shrub with bushy growth when trained. Arabica has a delicate flavor and balanced aroma coupled with a sharp and sweet taste. They have about half the amount of caffeine compared to Robusta. Arabica produces superior quality coffee but is susceptible to diseases like leaf rust and pests like white stem borer. Arabicas are harvested between November to January and are typically grown on higher altitudes ranging from 600 to 2000 meters in cool, moisture-rich, and subtropical weather conditions with rainfall ranging from 1600 to 2500mm. This leads the systematic breeding efforts for genotypes with respect to leaf rust resistance, high yielding potential, wide adaptability, and superior quality.
So far CCRI has developed 13 Arabica selections for commercial cultivation. CCRI has released selections by employing the standard breeding strategies like inter-varietal hybridization followed by pedigree selection (Sln.2.Sln.3), pure line selection (Sln.1, Sln.4, Sln.8), interspecific hybridization followed by backcross breeding (Sln.6), double-crosses( Sln.10), multiple crosses (Sln.7.3) and introgressive breeding (Sln.5A, Sln.5B,Sln. 9, Sln.12 and Sln.13) using spontaneous tetraploid interspecific hybrids like Devamachy and Hybrido De Timor (HDT).
Selection . 1 (S.288)
This was a selection released during 1936-37. S.288 was developed by the method of pure line selection from an S.26 mother plant, a putative natural hybrid between C. arabica and C.liberica . The plants have the capability of growing vigorously and are resistant to leaf rust races I and race II and were superior to other varieties like Chiks and Kents under cultivation then. Fruits are round with broad discs and orange-yellow to red in color, popularly known as ‘golden drops’. This selection produces a high percentage of defective beans (20-30%) with a moderate yield of 800 – 1000 Kg/ha. The liquor quality is rated as Fair Average Quality.
Selection .2 (S.333)
This selection was released in 1940. It is a hybrid of S.31 X S.22. Initially, this was recommended for cultivation, because of its hybrid vigor and resistance to leaf rust. Seed distribution was withdrawn subsequently, because of high bean abnormalities.
Selection .3 (S.795)
The most popular variety of Arabica coffee in India, released during 1945-46. This variety is the most widely adaptable and cultivated variety. S.795 was developed from the cross between S.288 and ‘kents’ coffee with the main objective of minimizing bean abnormalities in S.288. The fruit (cherries) are medium in size and oblong in shape, each node produces around 14 – 16 cherries. Beans are oblong, bold with 60 to 65% ‘A’ grade, and liquor is balanced with good body, good acidity, and fairly good flavor. The plants of S.795 are vigorous and wide-spreading with profuse growth and yield potential of 1500 to 2000 kg /ha. It is resistant to the common rust races I and II but susceptible to race VIII.
This selection includes three Ethiopian Arabica collections viz. Cioccie, Agaro, and Tafarikela. Among these, the first two exhibits semi-erect branching while tafarikela shows drooping nature. All these are moderate yielders. Fruits are long, bold, orange-red with projected honey discs, occasionally with persistent calyx in Agaro and Cioccie. Beans are bluish-green, long, and bold with 65% ‘A’ grade and 25% ‘B’ grade with excellent liquor quality. On the other hand, fruits are relatively small in Tafarikela and ripen early compared to all Arabica varieties. Cioccie and Agaro are resistant to leaf rust races I, II, and VIII. Though Tafarikela is susceptible to rust, it exhibits horizontal resistance showing very less rust build-up under field conditions.
Selection .5 ( Sln.5A and Sln.5B)
Selection 5 includes two separate families of crossbred lines between Devamachy x S.881 (Wild Arabica Rume Sudan) given as Sln.5A and Devamachy x S.333 as Sln 5B. Devamachy is a spontaneous Robusta x Arabica hybrid. The plant of Devamachy x S.881 (Sln.5A) shows vigorous vegetative growth with an erect branching habit. The leaves are relatively small, narrow, elongated, and leathery with a wavy margin. Young leaves (leaf tip) are generally green in color and the plant exhibits field resistance to leaf rust. Even though rust susceptibility is seen in some plants, defoliation is not common. Fruits are round to oblong, variable in size with long peduncles (stalks) and 8 to 12 per cluster, relatively late in ripening. Sln .5A has a yield potential of 1200 to 1500 Kg/ha and produces nearly 40% B grade beans. Sln.5A is a very popular and the most cultivated variety in non-traditional coffee areas, especially in Andhra Pradesh.
Devamachy x S.333 line (Sln.5B) is characterized by uniform, medium-sized, semi-drooping plants. Leaves are elongated, medium in size, and young leaves are light bronze in color. These plants also exhibit higher resistance to leaf rust. Fruits are bold in size with 60 to 65% ‘A’ grade and have a yield potential of 1500 kg/ha. Liquor in both Sln.5A and Sln.5B is FAQ to FAQ+ in quality.