A. Santa Ram

Introduction The Arabica coffee plant is a Dative of the African continent. Southwestern highlands of Ethiopia, Boma Plateau of Sudan were reported to be the possible home of Arabica (Coffee arabica L.). Arabica is the only tetraploid form of the genus Coffee L. with 44 chromosomes (2n-9x=44). Tropical rain forest areas from Uganda, Togo. Central Africa extending up to the Atlantic coast countries Benin, Congo to Guinea were observed to be the abode of Robusta (Cuffta canephora Pierre ex Froehner). Robusta and all other species of Co/Ice are diploids with 22 chromosomes ('_n='_x=22). These commercially important species as well as many related species were introduced into the many countries that produce coffee by the colonial powers in the Sib and 19th Centuries. Initial introductions were followed-up by research coons in the intentions of establishing gene banks and at present almost all coffee growing countries have their fair share of it species collection.

Importance of Coffea species in Gene Banks

Scientific studies clearly established the fact that (here are over IOU species in the genus C'uffea and all these species form a closely related group in the family Itubiaceae. Studies also indicated that while the species of Coffea arc morphologically distinct. their genetic architecture is very similar with relatively easy transfer of genes between species. In the course of these studies, scientists in India and elsewhere created very unique coffee plant materials combining the genes of diverse diploid species in either diploid or tetraploid form. Sonic of these materials are currently exploited for commercial coffee production in different countries.

In India, such efforts started as early as 1937 and a cross was effected between Robusta (5.274) and Arabica (Kents) in the intention of combining the rust resistance and cluster characters of Robusta and the quality character of Arabica in a synthetic type. Even earlier to this effort, scientists of WO initiated prospection exercises to collect the diverse indigenous materials such as Doobla, Nethraconda. Chandrapore. Jackson and Hamilton hybrids generated by enterprising coffee planters. Sonic of (Item were actually hybrids generated by crossing Arabica with either Robusta or Liberica (C'. Iiherica Bull. ex Hiern.). Devatnachy hybrid is a putative natural hybrid of Arabica and Robusta collected from the Devamachy Forest near Margolly Estate in Kodagu.

Popular Indian Selections of Arabica Coffee

5.26 and Origin of S., '95 (Sln.3)

5.26 was a collection front Doobla Estate.'I'his was collected in the year 1928. 1-he observations on the first generation front one mother plant indicated a larger sustained resistance against the principal adversary. the leaf rust disease caused by Ilemileia vastairix B. ct Br. As this was Colt helpful to the planting community, this material 5.288 (first generation derived by self-pollinating S 26) was released for commercial exploitation as early as 1935, as Selection-I. However, it was soon noticed that S.288 produces considerable quantities of bean defects (triage) and iu order to bring in the bean and liquor quality features a selected plant of S 288 was crossed with famous Kents Arabica known for its quality in the intention of combining the resistance against races I and 11 of the rust fungus and the quality traits of these parents. Selection was exercised for the combination of quality and resistance characters in (lie hybrid generation (F I generation) and a few progenies were raised front selected mother plants. Out of them, 5.795 was found to be better in both quality and resistance characters and was released for commercial exploitation in the year 1945. as Selection-3. Later research a t CIFC (Centro de Inyestigacao das Ferrugcns do Cafeciro also known as CRRC or Coffee Rusts Research Centre), Portugal revealed that 5.795 and other early Indian coffee selections carry the gene SH3 that was not found in any other .Arabica ge iiplacin. including the gerniplasm from Ethiopia. This was reported to have been derived front the species C. liberica. native to West Africa. However. the gene was.. so far, not isolated from C. Iihcrica. DNA marker studies revealed the presence of similar AFI.P markers in C. liberica and the 5.288 derivatives 5.795 and 5.1934. From the available information on markers and the stability of the transmission of this gene in breeding exercises, it can be inferred that SH3 originated by an initial segmental recombination between chromosomes of C. liberica and C. arabica followed by another reconihiriation event within the rust resistance taelcor, to create the unique gene that Is Insulin only in the early Indian coffee electron.

For the initial extended trials.. sued derived by self-pollination of selected mother plants was distributed and performance observations indicated its wide adaptation in the coffee tracts of all traditional areas and up to 75% of the plants resistant to leaf rust. Demand for the seed of this material has increased and in the late 1950s and 1960s large-scale seed distribution from open-pollinated seed-plots witnessed a fall in its resistance. There were two phenomena happening simultaneously. One is the appearance of new races VIII (V2.3,5) and XII (VI,2.3,5) of the rust fungus that could defeat the resistance imparted by the gene combination SH2,3.5 and the other is actual loss of the gene SH3 front this combination. Races Vill arid X11 quickly stabilized on this selection in the 1960s as they carry combinations of onh_ a few virulence genes that could overcome the resistance imparted by 5112,3,5 resistance gene combination of the host. Presently, there are at least, two more rust races that can also defeat the resistance of 5.795. These are race XIV (V2,3.4,5) and race XVI (V1,2,3.45). The loss of SH3 gene was understood recently when a number of rust spore samples collected front 5.795 in India were subjected to race differentiation at CIFC. Portugal. Almost all samples were identified to be races I and II. to which 5.795 %sits supposed to be resistant. On the other hand. the second parent involved in the evolution of S.79.5, the Kents Arabica was known to be susceptible to these races of the rust fungus. Thus, evidently, the gene SH3 contributed by 5.288 is not present in the present day populations of S.795. How this could have been lost, can be explained by combining the genetic and evolutionary logic. Thus, plants carrying the SH3 gene in association with 5112 and 5115 are expected to be producing pollen grains and ovules ())tale and female varieties of plants) carrying these genes independently or in combinations such as St12. SH3 and '31-15 or possibly SH2,3. SH2,5 and SH3,5. Among these types of pollen grains only those which are most competitive in reaching the stigma of the pistil, germinating there and producing pollen tubes that grow faster to reach the ovules would be successful in effecting (he fertilization leading to fruit and seed development. 'this is the rule of natural selection. Thus. SH3 being a foreign gene (that of C. liberica) coming to be present in C. arabica could have been discriminated by true pistillar tissues on which the pollen grains carrying this gene should germinate, to be effective in fertilization. This leads to a situation where many of the fertilizations would have been, effected by the pollen grains carrying the genes SH2 and 5115 of C'C arabica resulting in the seed derived from open pollination carrying the combinations of genes derived from the original Arabica parent the Kents. This explanation is validated by the fact that the rust races infecting 5.795 today are mostly races-I and II that were infective on Kents.

On account of the above, 5.795 plants infected with rust fungus largely shed their leaves leading to an almost complete exposure of the main stem rendering it easily accessible to the devastating pest, the white stem borer (Xvloirechus quadripes Clievrolat). Borer infestation ultimately leads to the death of the plants. An important point about plants is that leaves play a key role in all life activities of the plant, Leaves are the site of all biosynthetic activity producing, even constituent that is needed for the plant to lead a healthy life. Thus, loss of almost the entire leaf complement leads to very large compromises in the fitness of the plant. Thus. as the time passed 5.795 was found to possess susceptibility to stein borer as well as a range of other adversaries also.

Foregoing discourse leads to the conclusion that growing S.795 is more demanding in terms of disease and pest management at present as well its in future. Thus, it is a particularly difficult selection for cultivation by the small growers and growers iii the marginal and sub marginal areas where the disease and pest problems are very acute. For these sections of growers, it is recommended that newer selections like SA, Sln.5R, Sln.6 and SIn.9 may be taken up for cultivation on account of their large manifested resistance against the leaf rust fungus. At present the level of observed resistance in these selections ranges from 85-90%.

5.795 helped the industry in increasing production and reducing costs to some extent. In the 1960s. Cover Story to he of large prevalence on this selection. Since this selection has been showing an increased susceptibility to leaf rust, it is best recommended for higher elevations where the climatic conditions arc not conducive for the development of leaf rust fungus. 5.795 is found to be well adapted in 7 of the I I sub-zones of Chikmagalur District. It is not recommended for the sub-zone 2 (Balehole, Magundi areas), sub-zone 7 (Siravase, Saragod, Bagse areas), sub-zone 9 (Koppa, Sringeri, Mandagadde, Thirthahalli. Balchonnur, Sangameswarpet areas) and sub-zone I I (NR Pura area). Its performance is good in all sub-zones of I lassan District and sub-zones I (Madikeri. Somwarpet. Sunticoppa. Sha nivarasanthc. Karnangcri, Makkandur, Galibeedu, Shanthalli, Koothi, Tholur Shettalli, Kundalli. Thakeri, (.iarvale. Mouvathoklu, Kumboor. Cowcody. Malambi areas) and 2 (K adagadal, Heravanad. Aravathoklu, Mckeri. Bettager, Biligeri.. Kibbetta. Kusboor. balagunda. Madapura. Valnoor, Abyathamangala.. NeIliInudikeri, Chcttalli. Kodagarahalli, Kodlipel and Wooliguli areas) of Kodagu District and Biligiri Hills as well as all sub-zones of'Famil Nadir area and the sub-zone 2 of Andhra Pradesh. On account of its early popularity and wide adaptation it is already planted in large areas of all these zones at elevations from 2800 to 3500ft from MSL. Leaf rust also thrives well in areas at lower elevations between 2800 and 3000 ft. Hence strict plant protection practices are necessary to obtain good performance from this selection. future planting of this is recommended only at higher elevations of 3000-3500ft with rainfall of over 80" Distinctive characters of this selection are: the bushes are tall. vigorous and spreading with profuse growth. It was reported to produce large percentage of defective beans (20 -30%) due to false polvembryony in some populations. this was found to be susceptible to coffee leaf rust races VIII. XII.. XIV and XVI. The selection has a high potential yield of up to 2000kg:ha. The beans are oblong. hold (up to 70%A-grade) with good cup quality.

Slu.5 (Devanrach), Itch rid)

This selection became popular with the growers since the mid 1990s. This selection comprises three distinct cross-bred lines derived by crossing Devamachy hybrid (natural Arabica-Robusta hybrid) with 5.881 (wild C. arabica from AngloEgyptian Sudan. named as Rume Sudan carrying a high level of horizontal resistance to leaf rust), 5.333 (another collection from Doobla Estate) and S.26 (Doobla l lvbrid). Out of these three. 5.333 x Devamachy hybrid became popular on account of its rust resistance. good productivity and wide adaptation at elevations from 3000-3500ft from MSL. This selection is named as Sln.5B. A distinctive feature of Sln.5B (5.2931) is that the bushes arc uniformly medium sized and branches are semi-drooping. Plants manifest high resistance to leaf rust. The fruits are bold, producing up to 65% .4-grade beans. This selection has a moderately high yield potential of I500kg ha. Beverage quality of this selection is FAQ to h:AQ+.

Adaptation of this selection is found to he good in the sub-zone 4 (Mudigere, Kalasa and Devarunda areas) an (I sub-zone 8 of Chikmagalur district (Vastare). Mallenahalli to Santaveri areas); subzone 2 (Kadagadal, Biligeri. Heravanad, Aravathoklu, Mekeri, Bettager. Kibbetta, Kusboor.. balagunda, Madapura. Valnoor, Ahyathamangala. Nellihudikeri, Chcttalli, Kodagarahalli, Kodlipe(, Wooliguli) of Kodagu district in the elevations ranging from 28003500ft. and rainfall of 60-80" and above.

Another line of Devamachy hybrid that was distributed earlier as Sln.5 is the one derived from the cross Devamachy x 5.881 (Runic Sudan). This line manifests excellent vegetative vigour and is known to be productive (1200 kg/ha). It manifests a high level of resistance against leaf rust and is well adapted in the range of elevations front 2600-300011 and rainfall of even 50-60". This selection is now known as Sln.SA.

Sln.SA is characterized by high vegetative vigour demanding good bush management by way of desuckering. centring and removal of minute vegetative growth in the post blossom and post-monsoon growth cycles. Its leaves are linear, oblong, thick and leathery. This selection manifests very high field tolerance to the leaf rust disease on account of the combination of resistance factors from Devamachy and Runic Sudan. It is a moderate yielder. producing up to 1200 kg with 40-45% 13grade beans. Beverage quality of this selection is reported as FAQ-FAQ-.

Shr.6 (Robarhica hybrid)

This selection was developed with the intention of combining the quality traits of Arabica and high rust resistance observed in Robusta. Similar attempts were made in Brazil and Ivory Coast also and Arabica-Robusta hybrids known as Icatu and Arabusta were created. Indian eflorls were different to the extent that the female parent of the cross was 5.274 Kobusta, whereas in Brazil and also in I ory Coast the female parent was Arabica. Another important difference was that tetraploid Robusta plants derived by colchicine treatment were in'olyed as stale parent in those countries while a normal diploid Robusta plant was involved in the cross in India. Because of the chromosome number differences of the parent species. Robusta being diploid and Arabica tetraploid, the first generation hybrid was a Iriploid with high sterility. This was backcrossed to Kents Arabica to obtain a reasonably fertile progeny of tetraploids. Another backcross of these tetraploids to Kents Arabica restored most characters of Kenis Arabica and the resistance trait of Robusta was maintained in these progenies by selection. Progenies front this backcross were distributed for commercial cultivation as SIn.G.

The distinctive characters of Sln.(i are: somewhat broad leaves with wavy margins as found in Kcnts variety, light bronze colour in terminal leaves. high field tolerance to rust disease and tight fruit clusters as observed in Robusta. Branches of this selection are semi-erect initially but lend to droop with crop. Inlcrnodal length is intermediate hctwecn 5.795 and Sln.9. It has a high yield potential However. the realized yields range from 1200-2000 k2lha If is well adapted in the medium range of elevations front 28003300f1. and above up to 4000 li. and performs well in rainfall ranges of 60-80" and above. Thus, it is found to be performing well in all the sub-zones of Chikmagalur district except the sub-ronc2 (Balehole and fvlagundi areas), subzone 7 (Siravase, Saragod and Bagse areas) and sub-zone II (NR Pura area) where only Robusta can be grown. It is well adapted in all three sub-zones of Hassan district. three sub-zones of Kodagu district (sub-zones I. _2 and 4), sub-zones I (Anamallais, Coonor, Gudalur and Peruntalmalai areas) and 4 ((judalur area) of Tamil Nadu and sub-zones 2 (Nellianipa(hvs) and 3 (ldukki area) of Kerala, lit the nontraditional areas of Orissa and hiizorant_ Nasalaund and NC Hills of Assam in North Eastern Region also SIn.6 is found to be performing well

Sin. 7 3 (San Rarnon Hybrid)

San Rant on is a dwarf mutant of Bourbon coflce Cars( reported from Costa Rica. It was introduced into CC'KI gene bank during 1953. This mutant confers the advantage of high density planting and high yields in cultivation. Original San Ranton is highly susceptible to lead rust. To improve its resistance. San Ramon was successively crossed with 5.795, Agaro/Cioccie and finally HIT. Advanced generations were developed by selection (or dwarf character. resistance to leaf rust and aood yield alaid distributed as Sln.7.3. Improvement of San Ranlon wits taken tip only in India. while in Brazil and other countries other dwarf mutant Calurrit wits adopted for improvement.

Distinctive characters of SIn.73 are: dwarf stature of the plants, high fruit cluster density because of short internodes and moderately good resistance to leaf rust. 1' he variety has potential to yield good crops of over 1500 kglha, but is prone to crop strain leading to large annual variations. Even though this selection may have wide adaptability, it is generally preferred fix planting at high elevations in wind prone areas as well as low elevations and low rainfall areas because of adaptability in drought prone areas. Sonic growers of Pulneys and Shvaroys in Tamil Nadu still maintain this selection. Sln.7.3 segregates into dwarf and tall types in a ratio of 70:30 in the seed progeny. It is possible to select the dwarf plants in the nursery stage itself by measuring (lie length of "soldier stage" seedlings. Shorter seedlings ,row into dwarf plants while the longer ones grow into tall plants. Height of the seedling and internodal length al the stage of transfer to field (5-6 pairs of leaves) are also good indicators of stature plant stature. Low height of the seedling and short internodes determine dwarf nature. Separation of dwarfs from tall plants is needed to obtain a land file field.

SIrr.9

Hibrido de Firrior (JIM) is -,lit exotic natural hybrid of Robusta and Arabica manifesting the highest resistance to leaf rust. This genotype was introduced into CCRI gene bank in 1960 and was crossed with several Arahicas like Bourbon. S12Kafta. Tatarikela. Geisha and high resistance to these Arabica Grains. Evaluation of these hybrid lines over many years revealed that H DT x Tafarikela cross is superior in its field resistance as well as yield performance (- 1700 kgoo'ha, mean yield of 23 years). This was released as Sln.9 for commercial cultivation.

Distinctive characters of' this selection include tip leaf colour of bronze verging up on copper, drooping branches, longer internodes and high manifested resistance to leaf rust and good adaptation in drought prone areas. Its beans are generally bold with 65% A-grade.

ibis selection is found to have wide adaptability in different coffee growing zones of our country. Thus. its performance was found to be good in the sub-zones I. 4. 5, 6. 8, 9 and 10 of Chikmagadur, in all the three sub-zones of Hassan. in the sub-zones 1, 2 and 4 of Kodagu, sub-zones 2. 3 and 4 of Tamil Nadu and sub-zone I of North Eastern Region.

Cauvery

Cauvery became popular in the late 1980s on account of its dwarf stature, precocity of yield and high yield potential of up to 3000 kL,,/ ha and manifested resistance against leaf' rust at that time. This material went largely into the plantings in marginal areas that came under coffee at the given time. Later years have seen a complete decline of the resistance of this material that also rendered it amenable for stern borer attacks. However, some planters are still mains wining this selection at high altitudes above 3000 ft. where the leaf rust cannot thrive well. Thus, this selection is recommended to high elevations above 3000 It. only.

All Indian Arabica selections have a good cup quality that is well accepted in the National and International markets. Arabica Selection 9 has won international fine cup awards also. Cup quality of Indian coffee selections is presented in 'fable l.

Popular Selections of Robusta Coffee

Robusta coffee is vet' resistant to the diseases and pests that cause considerable damage to Arabica. Selection JR (S.270 and S.274) This selection is a composite of the progenies of two high yielding mother plants. These two genotypes grow into moderately large trees with vigorous growth. Their leaves are broad and light green in colour. Fruits are hold and borne in tight clusters of 30-50 fruits. Fruit ripening in this selection is usually late towards the middle or end of January ever' year. Out turn ratio of this selection is 5:1. Beans of this selection arc also bold producing about 40-43% A-grade. Liquor is rich in body and the cup is neutral. On account of its spreading growth h,^.bil, this selection requires to be planted at a spacing of 10 x 10 ft. This selection recorded yields of 1000 kg under rain fed conditions. Under irrigation this selection yields up to 2500 kg' ha. S.274 is preferred over S.270 on account of its larger proportion of bolder beans and wider adaptability.

This selection is found to he pertonning well in the sub-zone 2 (Baleholc and Magundi area). subzone 4 (M9udigere, Kalasa, Dcvarunda areas), sub-zone 5 (Kottigehaia. Banakal and Ilanlhur areas), sub-zone 6 (Aldur. Joldal, Kabbinahalli, Makonahalli, 1losapura, Jagaravalli, Thanigebylc, I langaravalli, Heggodlu. Nandipura, Jannapura and (ionibecdu areas), sub-nine 7 (Saragod, Siravase and Rape areas) and sub-zone 9 (Koppa, Sringeri, )vlandagadde, Thirthahalli. Balehonnur and Sangameshwarpet areas) of Chikmagalur District. ft is also adapted well in the sub-zone I (Flanbal. Ileggadde, Hc(hur, Igoor and Yeslur areas) of Flassan District. In Kodagu Distrtict, this selection performs well in the sub-zone 3 1 (CGonikoppal. Napoklu, Virajpet, Siddapur and Srimanagala areas), sub-zone 5 (Ratigasamudra and Nanjarayapatna areas), sub-zone 6 (faloor, Bethu. Kakkabbe, Nelgi, Peroor. Ballarnavati, Aivyangeri, Arapauu, V. Badaga, Kuttandi, B. Shettigeri, Nangala. Kannanga la, Heggala, Kedamullur, Kurchi, Beerugi. Nernmale, Theralu and Binmani areas) and sub-zone 7 (Ilathur. Kaikcri, Kirgoor, Kunda, Mayamudi, Nitoor, Devarapura, Pollibetta, Amathi, B. 13anangala, Ryrambada, Cuyya, Karmad, Kalathmad and Puliyeri areas). This selection is also well adapted in the three sub-zones of Kerala state and sub-zone 2 of NEIL.

Selection ?R (Balehwurur RobusTa, BR Series 9, 10 & 11)

Ibis is a clonal selection derived from 5.274 and has similar adaptation and performance. It is observed that this selection yields about 6-7 more of A-grade in its produce.

On account of obligate cross pollinating reproduction of Robusta coffee, the variation loads in seed derived populations are considerably large (up to +0%). Thus, the seed progeny from selected mother plants is often found to be very variable. To reduce the variation loads in commercial populations, clonal propagation is practiced. Robusta clones arc becoming popular in our country also. A point of importance is that the clones should be developed front a good number of selected mother plants in order to ensure that self-sterility does not interfere with production. Polyclonal gardens planted in specified agronomic designs like double-row and hedge-row planting were observed to be performing very well.

Selection 3R (Co ngensi.s x RobusTa, C x R)

l his is a hybrid variety developed through interspeciftc hybridization with C. rongeacis and C'. ( anephura as parents. These are very closely related species that arc also closely related to C. arabica. Congensis is a compact bush with drooping branches and better bean quality than Robusta. From the backcross of the original hybrid to Robusta parent, selections were made and sib-mating of the selected plants led to the evolution of the popular selection C x R. Because of its compact growth habit, this hybrid can be planted at closer spacing like 3x5 or 9x9 f. Fruiting branches carry about S-9 bearing nodes with 30-40 fruits in each cluster. Clusters are tight as in Robusta. This is a relatively early ripener with an out turn ratio of 4.5:1. Beans are bold and golden brown with a frequency of 50-54% A-grade. Liquor is soft ' Indian Robustas are also known for and neutral with light to fair acidity. Cup rating awarded to this selection has also won fine cup awards. is fair to good. Under rain fed conditions, this selection was observed to be yielding about C x R is also found to he doing well in all the zones where S.274 is observed to be performing well. In general all Robustas respond well to timely irrigation for blossom and backing- Assured yields of Robusta arc possible under irrigated conditions.

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