Final SPH -JHS Coverpage 16-2 Jan 2021 single 301 J. Hortl. Sci. Vol. 16(2) : 301-308, 2021 This is an open access article d istributed under the terms of Creative Commons Attribution-NonCommer cial-ShareAl ike 4.0 International License, which permits unrestricted non-commercial use, d istribution, and reproduction in any med ium, provide d the original author and source are credited. Original Research Paper Vegetative vigour, yield and field tolerance to leaf rust in four F 1 hybrids of coffee (Coffea arabica L.) in India Divya K. Das1, Shivanna M.B.2 and Prakash N.S.1* 1Central Coffee Research Institute, Coffee Board, CRS (P.O) - 577 117, Chikkamagaluru Dist., Karnataka, India 2Department of P. G. Studies and Research in Applied Botany, Jnana Sahyadri, Kuvempu University, Shankaraghatta - 577451, Karnataka, India *Corresponding Author Email : drccri2020@gmail.com ABSTRACT Four F 1 hybrids of arabica coffee (Coffea arabica L.) developed with the primary objective of pyramiding the S H 3 gene for leaf rust resistance in a commercial variety ‘Chandragiri’ for achieving the long-lasting resistance to leaf rust, have been evaluated in field. Two hybrids (S.5083 and S.5084) were derived from a donor heterozygous to S H 3, while the other two hybrids (S.5085 and S.5086) were developed from donor homozygous to S H 3. Among the hybrids, S.5086 recorded superior yield performance during individual years with a maximum yield of 1611 kg/ha during 2020-21 and the four year mean yield of 1313 kg/ha. The hybrid exhibited maximum heterosis over mid parent (29.10%) and better parent (17.12%) and S.5086 progeny also manifested high field tolerance to leaf rust pathogen as the entire plant population was free from the disease incidence throughout the study period. The findings of the present study established the efficiency of F 1 breeding strategy with simultaneous pyramiding of rust resistance genes for development of vigorous, high yielding and durable rust resistant F 1 hybrids in arabica. The F 1 hybrid, S.5086 with promising performance in terms of crop yield and high field tolerance to leaf rust has potential implications for commercial exploitation. Key words: Coffee, F 1 hybrids, durable resistance, pyramiding and S H 3 gene C off ee, t he mos t p op u la r b ever a ge c r op is cultivated in over 50 countries across continents with high export potential. The foreign exchange revenues from coffee exports constitute substantial share in the national economies of the producing countries. The turnover of the world coffee industry is over $ US 40 billion annually and the industry provide direct employment as well as livelihood opportunities to approximately 20 million people in cultivation, on-farm processing, value addition and trade. India is the 7th largest producer of coffee with a cultiva ted a r ea of 4. 59 la kh ha a nd a nnua l a ver a ge pr odu ct ion of 3 . 2 0 la kh M T, whic h a ccounts for a bout 3. 5 % of the wor ld coffee production a nd 4.5% sha re in globa l expor ts. Commercial coffee comes from two species viz., Coffea arabica L. and Coffea canephora Pierre ex A. Froehner that are popularly referred as arabica and robusta coffees, respectively. Arabica coffee types manifest susceptibility to major diseases and pests while r obusta is mor e toler a nt to these diseases and pests but the bean and liquor quality of robusta is inferior to arabica. Among the various diseases that affect arabica, coffee leaf rust (CLR) caused by an obligate parasitic fungus, Hemileia vastatrix Berk et Br is the most prominent one that cause severe crop losses to an extent of 70% in susceptible cultivars, if proper control measures are not adopted (Anon., 2014). The wet weather with intermittent rainfall & sunshine, relative humidity over 80% and temperatures between 220 & 240C are the ideal conditions for CLR flare-ups. INTRODUCTION 302 Das et al J. Hortl. Sci. Vol. 16(2) : 301-308, 2021 Therefore, breeding for rust resistance has been pur sued on highest prior ity in severa l ar abica growing countries including in India, that resulted in develop ment of s ever a l c off e e va r iet ies manifesting varying levels of resistance to CLR. However, because of the adaptive ability of the H. vastatrix, br ea kdown of resista nce under field conditions has been experienced in the commercial varieties due to evolution of new virulent rust races from time to time. At present, a s many as 45 different physiological races of rust with ability to infect different coffee genotypes are distributed in various coffee-growing countries (Rodrigues et al., 1993 a nd Pra ka sh et al. , 2005). T he wea ther conditions that prevail in Indian coffee growing regions are highly favourable for leaf rust pathogen. As a result, high disease build up as well as race mutation leading to the evolution of new virulent races of rust with ability to overcome the resistance in varieties released for cultivation has been a common phenomenon. At present, over 35 different rust races are found distributed in coffee tracts of India. Therefore, development of varieties with long lasting resistance in field is the priority of arabica coffee breeding in India. The host resistance to coffee leaf rust is reported to be governed by nine resistance genes, designated as S H 1 to S H 9, distributed across the coffee gene pool. Among the commercially cultivated species, four resistance factors (S H 1, S H 2, S H 4, S H 5) were identified in C. arabica the only tetraploid species of the genus while four other factors (S H 6, S H 7, S H 8, S H 9), were reported from diploid species, C. canephora and S H 3 factor from another diploid species C. liberica [Wagner and Bettencourt, 1965 ; Vishveshwara, 1974 ; Bettencourt and Rodrigues, 1988] . It ha s been well esta blished tha t the resistance genes identified in C. arabica, are less durable under field situations while the genes viz., S H 6, S H 7, S H 8, S H 9 introgressed from the diploid species either fr om C. canephora or fr om C. liber ica (S H 3) a r e fou nd to ma nifest dur a ble resistance. Hence, the resistance breeding strategies ha ve b een ma inly focu s ed on p yr a miding of resistance genes of diploid origin into selected a r a bica genotypes by using the na tur a l inter- specific hybrids as donors. In order to expedite the pyramiding of resistance genes into outstanding cultivars by conventional breeding and to reduce the required time frame, F 1 breeding strategy is gaining significance. Fur ther, because of the domina nt nature, the resistance genes are expected to express in F 1 s resulting in long lasting resistance. With this objective, development of F 1 hybr ids has been pursued as a priority of Arabica coffee breeding in India since 2011. The present communica tion highlights the field performance of four such F 1 hybrids in respect to vegetative vigour, yield and field tolerance to leaf rust. MATERIALS AND METHODS The plant material included in the present study comprised of four F 1 progenies, S.5083, S.5084, S.5085 a nd S. 5086 gener a ted fr om recipr oca l c r os s es b e t ween t wo a r a b ic a genot yp es , ‘Chandragiri’ and Sln.10 (Table 1). Two elite plants of S ln. 10 , cha r a cter ized a s homoz ygous a nd heterozygous for S H 3 gene for rust resistance were used in crossing programme, in order to validate the differential response of hybrids, if any. All the four progenies were planted in a compact plot at research farm of Central Coffee Research Institute, Balehonnur, Karnataka, India (13º 22’ N, 75º 25’ E at an elevation of 2787 MSL), during the year 2012. The weather data pertaining to the study period is furnished in Table 2. In all, 60 plants per progeny were planted in a conventional square design at a spacing of 5’x5’ under a two-tier shade canopy, the top cover of evergreen natural forest trees and lower canopy comprising of fast-growing leguminous trees like Erythrina lithosperma Miq. (Dadap). The plants were trained on topped single stem system a nd standard agronomic pra ctices recommended for semi-dwarf arabica genotypes were followed. The progenies have been evaluated for vegetative vigour, field tolerance to leaf rust and crop yield. 303 Vegetative vigour, yield and field tolerance to rust in coffee Evaluation of agronomic characteristics For agronomic evaluation in respect of vegetative vigour, data was collected from 20 plants for each progeny (five plants per replication) for three crop seasons till the bush canopy was totally covered. For assessment of vegetative vigour, data on the growth parameters such as stem girth, bush spread, number of primary branches, length of the longest primary, Table 1. Details of parents and cross combination of F 1 hybrids Accession No. Parents/F 1 cross combination and their response to leaf rust pathogen S.3827 Sln.10 (double cross hybrid) Susceptible to 5 races of rust; Selected two plants homozygous {Caturra x Cioccie} and heterozygous to S H 3 gene (donors for S H 3 gene x introgressed from a diploid species C. liberica and also for {Caturra x S.795} good liquor quality attributes) S.4202 Chandragiri Resistant Plant selected from the base population that remained tolerant to all prevailing races of rust in India. It’s a C. canephora introgressed line. S.5083 Chandragiri Sln.10 – Heterozygous to S H 3 S.5084 Sln.10 - Chandragiri Heterozygous to S H 3 S.5085 Chandragiri Sln.10 – Homozygous to S H 3 S.5086 Sln.10 - Chandragiri Homozygous to S H 3 number of nodes per primary, inter nodal length and yield component characters such as number of bearing nodes per primary, number of fruits per node was recorded. The fruit yield per plant and progeny yield was recorded during harvest season i.e., Nov. - Dec. for four crop seasons from 2017 to 2020. Data was also collected from Chandragiri and Sln.10 the parents. Table 2. Weather data pertaining to the study period (2017-2020) Months 2017 2018 2019 2020 Tem. Rainfall RH% Tem. Rainfall RH% Tem. Rainfall RH% Tem. Rainfall RH% January 22 0 (0) 67 23 0 (0) 81 21 0 (0) 82 23 0(0) 74 February 24 0 (0) 65 24 0 (0) 79 25 0 (0) 62 24 0(0) 61 March 26 13 (0) 65 26 26 (4) 82 25 24 (3) 79 25 23(2) 72 April 27 48 (4) 74 26 108 (16) 78 27 59 (5) 77 26 77(9) 80 May 25 195 (10) 76 25 356 (17) 82 26 39 (6) 87 25 219(14) 84 June 23 404 (23) 85 23 692 (20) 88 25 199 (20) 87 23 270(20) 89 July 22 556 (30) 88 22 1179 (28) 86 24 530 (28) 89 22 440(27) 88 August 23 560 (20) 87 21 1169 (20) 91 23 1204 (31) 86 21 1057(20) 87 September 24 261 (17) 86 23 128 (10) 88 23 538 (21) 88 22 466(17) 88 October 24 109 (6) 87 23 150 (8) 84 24 431(22) 88 22 163(11) 85 November 23 11 (2) 82 23 28 (2) 78 25 48(2) 84 21 44(5) 79 December 22 1 (1) 69 22 25 (1) 78 25 9(1) 85 21 1(1) 85 Tem.-Average temperature, Rainfall - rainy days in parenthesis, RH-Relative Humidity J. Hortl. Sci. Vol. 16(2) : 301-308, 2021 304 Data analysis and estimation of heterosis among F 1 hybrids Analysis of va riance was carr ied out for ea ch character as suggested by Gomez and Gomez (1984). Wherever the treatment differences were found significant, Critical Differences (CD) were worked out at five per cent probability level and values were furnished. The treatment differences that were not significant are indicated as ‘NS’. Relative heterosis and heterobeltiosis manifested by each F 1 hybrid wa s calculated over mid parent (MPH%) = [(F1-MP)/MP x 100] and better parent, (BPH%) = [(F1-BP/BP x 100], respectively. Evaluation of Coffee Leaf Rust (CLR) incidence: Observations on leaf rust incidence were recorded during peak periods of disease expression i.e., May- June months during pre-monsoon season and Sept.- Oct. months during post-monsoon season, for four successive years, from 2017 to 2020. Data on CLR incidence was recorded on individual plants and plants with less number of pustules were also treated as susceptible to assess the population susceptible/ resistant in each progeny. The disease build-up on susceptible plants was also scored using the 0-9 scale of Eskes and Toma-Braghini (1981 cf Eskes 1989), where 0 = plants are free from the symptoms; 1= presence of one diseased branch. Likewise, grades were assigned based on progression of disease and 9= maximum disease incidence. Finally, the plants were grouped into four categories viz., 1= tolerant (free from CLR incidence), 2 = moderately tolerant (mild infection without any defoliation); 3= susceptible (medium levels of incidence) and 4= highly susceptible (high disease build up coupled with defoliation). RESULTS AND DISCUSSION Agronomic Evaluation – Growth characters All the four F 1 hybrid genotypes evaluated in the present study exhibited vigorous vegetative growth with compact bush stature which is expected when both the parents are semi-dwarfs. The data in respect of vegetative, yield and yield component characters is presented in Table 3. Table 3. Character means and analysis of variance for different morphological and yield component characters among different F 1 hybrids F 1 hybrid/ Stem Bush No. of Length of No. of Internodal No. of No. of Avg. fruit parental girth spread primary longest nodes length bearing fruits yield per line (cm) (cm) branches primary per (cm) nodes/ per plant (cm) primary branch node (kg) S.5083 38.5 349.5 19.1 98.9 20.0 5.2 9.9 14.7 1.95 S.5084 39.5 366.1 19.1 98.5 20.2 4.9 8.8 14.9 1.78 S.5085 37.0 333.7 19.8 94.3 19.5 4.7 9.1 14.0 1.89 S.5086 36.1 341.2 19.8 94.3 19.2 4.6 8.9 13.7 1.98 Chandragiri 36.2 322.2 20.0 87.4 19.1 4.9 8.6 12.3 1.69 (Parent 1) Sln.10 37.3 341.6 21.3 92.3 19.0 5.0 8.7 12.9 1.37 (Parent 2) SeM± 1.9 12 0.5 5.3 1.5 0.7 0.6 0.5 0.14 CD @ 5% NS NS NS NS NS NS NS NS NS From the data it is apparent that the hybrids exhibited uniform vegetative vigour with marginal differences in various characters. Among the F 1 progenies, S.5084 recorded superior growth in terms of stem girth (39.5 cm), number of nodes (20.2), bush spread (366.1); number of fruits per node (14.9). In contrast, S.5086 recorded more compact growth pattern as reflected in most of the growth parameters recorded, compared to other F 1 hybrid progenies (Table 3). Analysis of variance carried out for each character revealed that the character means among different hybrids are significant at P<0.05 with their parent populations except number of nodes per primary. These variations in terms of growth characters can be attributed to the gr owth pa tter n of the pa r ents a nd their cr oss combination used for generation of hybrids. Prakash et al (2006) evaluated 17 elite hybrid progenies for growth parameters, field tolerance to rust, clean coffee Das et al J. Hortl. Sci. Vol. 16(2) : 301-308, 2021 305 yield and bean characteristics in a specific agro- clima te in India. Analysis of va r ia nce of five mor phologica l cha r a cter s r evea led significa nt differences between the genotypes in respect of four characters (stem girth, bush diameter, length of longest pr ima r y a nd number of pr ima r ies per pla nt) establishing tha t the genotypes a re moder ately heterogeneous for plant architecture. Heritability was high (60%) for yield and 64% for field tolerance to leaf rust indicating low genotype x environment interaction for these traits. Heterosis for crop yield Data on year wise clean coffee yield among the F 1 progenies and the parents is presented in Table 4. In general, the production trend over the years from 2017-18 to 2020-21 has shown alternate bearing pattern which is common in Arabica coffee. Further, there has been an increase in quantum of yield both in parents and hybrids over the years. All the hybrids recorded higher yields over parents both during the on and off years. Statistical analysis of year wise yields showed significant differ ences among different genotypes and also the parents (Table 4). During the lean cropping years of 2017-18 and 2019-20, the mean crop yields (clean coffee) among the four hybrid progenies varied from 996 kg/ha (S.5083) to 1102 kg/ ha (S.5086) and 1161 kg/ha (S.5085) to 1232 kg/ha (S.5086), respectively. During the high cropping years i.e., 2018-19 and 2020-21, the mean yields ranged from 1233 kg/ha (S.5084) to 1424 kg/ha (S.5083) and 1415 kg/ha (S.5084) to 1611 kg/ha (S.5086). Among the hybrids, S.5086 recorded superior and consistent performance during individual years with a maximum yield of 1611 kg/ha during 2020-21 and the four year mean yield of 1313 kg/ha. Among the F 1 hybrids, the relative heterosis (MPH%) ranged from 15.83% (S.5084) to 29.10% (S.5086) while heterobeltiosis ranged from 5.08% (S.5084) to 17.12% (S.5086). Among the four F 1 hybrids, S.5086 recorded superior yield performance. Among the two pa r enta l lines, the yield in ‘Chandragiri’ ranged from 887 kg/ha (2017-18) to 1303kg/ha (2020-21) while in Sln.10, the year wise yields ranged from 741 kg/ha to 1041 kg/ha. Analysis Table 4. Year wise clean coffee yields in F 1 hybrids and parental lines F 1 hybrid Clean coffee yield (kg/ha) progeny/Parents 2017-18 2018-19 2019-20 2020-21 S.5083 996 1424 1179 1557 S.5084 978 1233 1086 1415 S.5085 1069 1325 1161 1457 S.5086 1102 1307 1232 1611 Chandragiri 887 1224 1070 1303 Sln.10 741 987 883 1041 SEm ± 31.17 73.17 55.56 46.70 CD at P = 5% 93.96 220.56 167.48 140.77 of relative heterosis and heterobeltiosis revealed that all the hybrids exhibited maximum relative heterosis (MPH%) that ranged from 20.7% (S.5084) to 37.5% (S.5086) during the high cropping year, 2020-21 except in S.5085. As regards to heterobeltiosis, all the hybrids except S.5083 recorded high BPH% that ranged from 10.26% (S.5084) to 24.24% (S.5086) during the low cr opping yea r, 2017-18. T hese differences in relative heterosis and heterobeltiosis, could be attributed to the yield of the parents during the respective years. Among the four F 1 hybrids, S.5086 recorded high BPH% in all the years that ranged from 15.14% (2019-20) to 23.64 (2017-18) except during 2018-19. Bertrand et al. (2005) evaluated the performance of F 1 hybr id pla nts der ived fr om C. arabica for production variables and reported that the F 1 hybrids produced between 22% (trial 1) and 47% (trial 2) more fresh berries than the parental lines in two separate trials. This difference was highly significant for trial Vegetative vigour, yield and field tolerance to rust in coffee J. Hortl. Sci. Vol. 16(2) : 301-308, 2021 306 2 (P = 0.00). From the studies on genetic parameters of Timor hybrid derived Arabica genotypes at IAC, Brazil, Mistro et al. (2007) reported that the greatest yield ga ins were achieved when selection wa s performed based on plot means and years of high yields. It was reported that under normal climate conditions, coffee yields usually increase from the first until the fourth/fifth year. Thereafter, the biennial yield cycles begin, characterized by the alternate high and low yields. From the results of the present study, it is apparent that both the parental lines and the hybrids reflected the alternate bearing behaviour. However, the consistency in production has been recorded in the hybr ids in cor r esponding on a nd off yea r s of production, alternatively. Dula (2019) reviewed the heterosis and combining ability studies for yield of Coffea arabica varieties in Ethiopia. From the studies conducted by Mesfin and Bayetta (1983), the extent of heterosis for yield was up to 60% over better parent. Out of nine F 1 hybrids, only one hybrid exhibited negative heterosis of -8%. The highest yielding hybrids Melko-CH2 and Ababuna showed 20% and 18% heterosis over the better parent respectively. Given the fact that the genetic distance and combing ability of the parental lines is critical for achieving the maximum extent of heterosis in F 1 hybrids, the heterobeltiosis to the extent of 23.64% over better parent and 37.5% over mid parent for yield in best performing F 1 hybrid (S.5086) in the present study is a significant point to consider for commercial exploitation. Coffee leaf rust incidence Data on coffee leaf rust (CLR) incidence among the four F 1 hybrids and parental lines is furnished in Table 5. Among the hybrids, the leaf rust incidence ranged from nil (S.5086) to 51% (S.5083) while in the two parental lines, the CLR incidence ranged from 2.8% to 30% in Chandragiri and 22% to 73% in Sln.10 during different years of study. From the data in respect of individual F 1 hybrids, it is apparent that the two hybrid progenies, S.5083 and S.5084 recorded relatively high susceptibility as 46.1% and 50.9% of population manifested susceptibility during 2019-20, the year that recorded high rust flare up due to favourable weather conditions. The parental lines also recorded maximum susceptibility (30% in Chandragiri and 73% in Sln.10) during the high rust year (2019- 20). In contrast, the remaining two F 1 hybrid progenies (S.5085 and S.5086) maintained high levels of field tolerance as the entire population of these two hybrids are free from the rust incidence. The high rust incidence manifested during the 2019-20 could be attributed to the favourable weather conditions i.e., high rain fall coupled with maximum number of rainy days during July and August months as well as ideal temperatures (190C to 240C). The quantum of rainfall though higher during July and August 2018, the number of rainy days were low thereby the rust incidence was relatively low compared to 2019. However, inspite of the favourable weather conditions during 2018 and 2019, the disease build up levels were recorded to be very low, in the hybrids S.5083, S.5084 and parent variety ‘Chandragiri’, the disease build up was characterized by the non-sporulating necrotic spots (group 2), indicating the high levels of tolerance. Further, the high levels of field tolerance to leaf rust in F 1 hybrid progenies (S.5085 and S.5086) could be attributed to the integration of the S H 3 gene in these hybrid populations as the Sln.10 parent used as S H 3 donor is homozygous to S H 3. In fact, the very objective of the F 1 hybrid breeding programme was to pyramid the maximum number of S H genes for rust resistance in a proven commercial arabica genotype to ensure long lasting resistance to leaf rust. The resistance in Chandragiri is governed by the S H genes of tetraploid arabica origin (S H 1,2,4,5) and S H genes (S H 6, S H 7, S H 8, S H 9) introgressed to C. arabica from diploid species, C. canephora (robusta coffee). The F 1 hybrids evaluated in the present study were developed with the primary aim of pyramiding of S H 3 gene of C. liberica origin in order to improve durability of resistance in Chandragiri. Two plants of Sln10, homozygous and heterozygous to S H 3 gene were consciously selected and used as donor parents (paternal) in crossing programme. Apparently, the two hybrid progenies, S.5083 and S.5084 were derived from the heterozygous donor while the other two hybrid progenies, S.5085 and S.5086 were developed fr om the homozygous donor pla nt. T hus, the variability for field tolerance to leaf rust in these four F 1 hybrid pr ogenies, could be attributed to the differences in pyramiding/ integration of S H 3 gene from heterozygous and homozygous donor plants. Analysis of the selected F 1 plants representing the susceptible and resistant plants in different hybrid progenies with SCAR marker linked to S H 3 gene confirmed the presence of the S H 3 gene (un-published Das et al J. Hortl. Sci. Vol. 16(2) : 301-308, 2021 307 data). This inference lend credence from the findings of Shigueoka et al. (2014) evaluated nine arabica coffee progenies with an objective to select high- yielding coffee progenies with resistance to coffee leaf rust for the state of Parana in Brazil. It was reported that the plant population of several genotypes derived from ‘Sarchimor’ and ‘Catucai’ were susceptible to coffee leaf rust and complete resistance was broken in several coffee plants of ‘Catucai’ germplasm. However, the interesting observation reported was that the genotype ‘F 6 of Catuai x (Catuai x BA-10 coffee)’ probably a carrier of S H 3 gene manifested complete resistance in more than 80% plants and inferred that the genotypes were heterozygous to S H 3 gene. Infact, there were several other earlier reports from Brazil that the coffee genotypes carrying S H 3 gene manifested complete resistance to leaf rust (Fazuoli et al., 2005, Pereira et al., 2005. Sera et al., 2007). The findings of the present study also in conformity with that of the earlier reports on high levels of field tolerance manifested by the two F 1 hybrids, S.5086 & S.5085 der ived fr om cr osses employing Sln10 pla nt homozygous to S H 3 gene. CONCLUSION The findings of the present study are of high applied value and clearly established the efficiency of F 1 breeding strategy for development of vigorous, high yielding and durable rust resistant F 1 hybrids in arabica. The extent of heterosis in arabica coffee is found to be dependent on the genetic distance and combining ability of the parental genomes. The two F 1 hybrids, S.5086 & S.5085 that recorded promising Table 5. Leaf rust incidence (% population) in different F 1 hybrids Acc. No 2107-18 2018-19 2019-20 2020-21 S.5083 10.3 44.5 50.9 10 S.5084 8.2 12.8 46.1 11 S.5085 0.0 0.0 0.0 5.0 S.5086 0.0 0.0 0.0 0.0 Chandragiri 2.8 20 30 30 Sln.10 22.0 60 73 60 performance in terms of crop yield coupled with high field tolerance to leaf rust have potential implications for commercial exploitation. ACKNOWLEDGEMENT The authors are grateful to the Director of Research, Central Coffee Research Institute, Coffee Board, for the support and encouragement received throughout the research study. Anonymous. 2014. Coffee Guide, Coffee Board, Bangalore, India, p 262. Bertrand, B.H., Etienne, C.C., Charrier, A. and Baradat, P. 2005. 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Crop Breeding and Applied Biotechnology 14: 88- 93. Vishveshwara, S. 1974. Periodicity of Hemileia in arabica selection – S.795. Indian Coffee 38:49– 51 Wagner, M. and Bettencourt, A.J. 1965. Inheritance of reaction to Hemileia vastatrix Berk & Br. in Coffea arabica L. In Progress report 1960- 65, Coffee Rusts Research Center, Oeiras, Portugal. p 121-123. (Received on 23.05.2021, Revised on 24.07.2021 and Accepted on 27.07.2021) Das et al J. Hortl. Sci. Vol. 16(2) : 301-308, 2021 00 Contents.pdf 01 Shalini.pdf 02 Sheikh.pdf 03 Debanath.pdf 04 Nimbolkar.pdf 05 Satisha.pdf 06 Kaur.pdf 07 Nitin Kumar.pdf 08 Varsha.pdf 09 Ravishankar.pdf 10 Swamini.pdf 11 Vijaykumar.pdf 12 Usha bharathi.pdf 13 Yogalakshmi.pdf 14 Adams.pdf 15 Lakshman.pdf 16 Yella swami.pdf 17 Varalakshmi.pdf 18 Sharon.pdf 19 Lamesssa.pdf 20 Divya.pdf 21 Wani.pdf 22 Event Report.pdf 23 Index and Last Pages.pdf