Arabica coffee (COFFEA ARABICA L) 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 Robustas. 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 Seed distribution was withdrawn subsequently, because of high bean abnormalities.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.
Selection . 6 (S.2828)
This was Developed by crossing robusta cv. S.274 X Kents Arabica. F1 progenies were found to be vigorous with Arabica type of appearance and robusta type of tight cluster. Bushes are tall, vigorous with spreading branches, and medium to long internodal length. Leaves are broad, thick and young leaves are bronze in color. Fruits are bold, round, arranged in tight clusters with 16 to 20 fruits per cluster, and ripening is relatively late. This hybrid is well adaptable at medium altitudes and shows mixed types of rust reaction, exhibits field tolerance to rust. The yield ranges between 1200 to 2000 kg/ha. Beans are bluish grey, round, and bold with 60 to 65% ‘A’ grade with liquor quality FAQ to FAQ+.
This is derived from the cross of San Roman (Dwarf mutant) with other Arabica’s. San Ramon was crossed with S.795 and Sln.7.1 was developed. Dwarf type in Sln.7.1 crossed HDT and Sln.7.3 developed. The dwarfs in Sln.7.3 are suitable for high-density planting (4ft x 4ft, 5ft x 4ft ) with a yield potential of over 1500 kg/ha but with annual variations for production. The original ‘San Ramon’ mutants were very compact in branching habit, with closer internodes and deep roots but highly susceptible to rust. Of the progeny of the mutant, 70% were dwarf type and 30% were tall types. Sln 7.3 is a late ripener, drought-tolerant and suitable for marginal areas. The liquor quality of FAQ to FAQ+.
This selection is a natural cross of Robusta x Arabica hybrid from Timor island and was introduced into India from 1968 -69 onwards. It is a pure line selection of ‘Hibrido de Timor’ popularly known as HDT. The plant phenotype closely resembles Arabica and possesses high vertical resistance to leaf rust. The bushes show compact growth with drooping branches and internodal lengths are very short. It is a moderate yielder (1000 to 1200kg/ha) and produces medium to bold beans. Cup quality is similar to Arabica (FAQ to FAQ+). Sln.8 is suitable for cultivation in medium altitudes.
As HDT is a rust-resistant cultivar, many crosses were made between HDT and other tall Arabicas such as Tafarikela, S.795, Geisha, S.12 Kaffa, and Bourbon. Among these HDT X Tafarikela is more resistant to leaf rust under field conditions and on average (23 years) yielded 1700 kg /ha at CCRI. The plants of Sln.9 are tall, vigorous with drooping branches, and medium to long internodes. Leaves are broad, elliptic, young leaves are dark bronze in color. Fruits are bold, dark red, oblong, and 12 to 16 per cluster and show early ripening. Beans are bluish-green, round, bold with 60 to 65% ‘A’ grade beans and liquor quality is excellent with a strong body, possessing distinct flavor in the cup. These plants are drought hardy and widely adaptable in the coffee-growing regions.
‘Caturra’ is a semi-dwarf mutant of Arabica. It has high yielding potential but these are highly susceptible to leaf rust disease. Hence, it was crossed with Cioccie and S.795. The respective progenies were again crossed to evolve the double-cross hybrid, Sln.10. The Sln.10 plants are compact and semi-dwarf in nature with profuse bearing habit and exhibit resistance to common rust races but these are susceptible to virulent races. Fruits are bold and produce nearly 65% ‘A’ grade beans. Cup quality is similar to S.795.
This is an interspecific hybrid derivative of C.arabica and C.eugenioides.Sln.11 bushes resemble arabica with erect to semi-erect branches and leaves are narrow, linear, and young leaves green in color. Fruits are oblong, 12 to 15 per cluster, golden red in color, and late ripening. The plants are resistant to leaf rust and moderately tolerant of drought. It is a moderate yielder but produces more B grade beans (30-40%). Cup quality is similar to Arabica.
Selection .12 (Cauvery/ Catimore)
Sln.12 was released in 1985. This is a semi-dwarf hybrid derived from a cross between caturra and HDT released for commercial cultivation. Its bushes are compact and vigorous with profuse branches and close internodes and are thus suitable for high-density planting. Leaves are medium in size and elliptical. The variety is an early bearer and fruits are dark red, round, bold, 14 to 18 in tight clusters. It was high resistance in initial years and now the resistance got broken down in later years due to the appearance of seven new rust races. This hybrid has the potential to yield an average of 2000kg/ha. Under different management conditions, the yield ranged from 800 to 6000 kg/ha. Beans are bold with over 60% ‘A’ grade and liquor quality is a FAQ to FAQ+.
Selection .13 (Chandragiri)
The variety ‘Chandragiri’, released in 2007, is a selfed F3 progeny of the cross between Villa Sarchi x HDT. Plants are semi-dwarf with vigorous growth and are large drooping types with broad leaves, dark green in color. Terminal leaves are light green in color. Fruits are elongated, 14 to 18 in number and loose in clusters, normal in ripening. Beans are bluish-green, long and bold with 20 to 25% MNEB (Mysore Nuggets Extra Bold), 27% ‘AA’, 35% ‘A’ grade. This variety is highly resistant to leaf rust and showed resistance of about 95 to 98% at CCRI. This is best for cultivating in higher elevations (3300 ft and above). This has given the average yield potential of 1156 to 1875 kg/ha from the 5 to 8-year plants. Liquor is a FAQ to FAQ+.