IPR 99-Dwarf arabica coffee cultivar resistant to coffee ringspot virus

‘IPR 99’ was derived from a cross between “Villa Sarchi 971/10” and “Hibrido de Timor 832/2”. It is a dwarf cultivar, resistant to coffee ringspot virus, partially resistant to leaf rust with semi-late ripening. ‘IPR 99’ presents partial resistance to necrosis and mummification of young fruits on field conditions. It presents special cup quality and high yield in lower and higher temperature coffee regions in Paraná State.


INTRODUCTION
The coffee breeding program of the Agricultural Research Institute of Paraná (Instituto Agronômico do Paraná -IAPAR), in the State of Paraná, Brazil, has been active since 1973. The development of 'IPR 99' aimed at high yield per hectare, lower cost per bag, improved quality and better yield stability (Sera 2001). 'IPR 99', released in 2005, is a dwarf cultivar, resistant to coffee ringspot virus and partial resistance to leaf rust (Hemileia vastatrix Berk. et Br.) (Sera et al. 2010a) and presents semi-late ripening. Also presents on field conditions partial resistance to necrosis and mummification of young fruits. This cultivar is recommended for semi-dense, dense and super dense planting systems in lower and higher temperature areas with annual average between 19 and 22 ºC in the State of Paraná.

PEDIGREE AND IMPROVEMENT METHOD
IPR 99 was developed using the genealogical method. It was derived from a cross between "Villa Sarchi CIFC 971/10" (Coffea arabica L.) and "Hibrido de Timor CIFC 832/2" (interspecific hybrid between C. arabica and C. canephora), performed at the Coffee Rusts Research Center (Centro de Investigação das Ferrugens do Cafeeiro -CIFC), in Portugal, where it was named HW 361. The F 2 genera-tion (HW 361-4) was received by the Instituto Agronômico de Campinas (IAC) and named C1816. In 1977, IAPAR introduced the F3 generation (C1816 -EP141 c.1567), named PR 77028. The F4 progeny PR LF 77028 was then selected. Individual plants were selected and advanced to F 5 generation, later named 'IPR 99', and released in 2005. Some progenies presenting higher percentage of plants with complete resistance to leaf rust were selected. These progenies were advanced to F 6 generation in 2009.

PERFORMANCE
'IPR 99' can be cultivated in regions with annual average temperature between 19 and 21 ºC such as Londrina (580 m altitude) and Congonhinhas (750 m altitude) municipalities, and in hot regions with 22 ºC annual average temperature, such as Itaguajé (350 m altitude) municipalities. The 'IPR 99' was evaluated in three locations of Paraná State, with 16 harvests, and it was more productive than 'IAPAR 59' and 'Catuaí Vermelho IAC 81' (Table 1).
IPR 99 is recommended for spacing between plants varying from 0.50 to 0.75m, depending on the local of cultivation and on the technologies used, such as fertilization, irrigation and pruning. In hot regions without irrigation, the spacing is narrower, since the canopy volume is usually smaller. Yield per plant could possibly increase  T Sera et al. by using wider spacing between plants; hence, it might be necessary more nutrition. The spacing between rows in mechanized intensive crop system can vary from 2.50 to 3.00 m according to the coffee crop area and the level of mechanization.

OTHER TRAITS
'IPR 99' presents semi-late ripening, which occurs before 'Catuaí'. At lower temperatures, with annual average between 19 and 20 ºC, the ripening occurs usually in July. At higher temperatures, with annual average between 21 and 22 ºC, the ripening occurs usually in May or June. In cool regions, 'IPR 99' must be planted in areas with reduced frost risk, since the fruit ripening is semi-late.
'IPR 99' can be used in association with other dwarf coffee cultivars with different ripening times (e.g. 'IAPAR 59' = semi-early, 'IPR 98' = medium, 'Catuaí' = late) in order to reduce the labor, infrastructure and equipment requirements. By using 'IPR 99' with other maturation cultivar groups for harvest in different times, the rain risk at harvest is reduced and it is easier and cheaper to produce quality coffee in the rainy and cool coffee regions of Paraná State.
The secondary plagiotropic branching of 'IPR 99' is lower than 'Catuaí' and higher than 'Mundo Novo'. 'IPR 99' has large and yellow fruits when ripe. The cup quality is equal or superior to cultivars of Mundo Novo germplasm. Coffee ringspot virus (= mancha anular) is a viral disease transmitted by the mite Brevipalpus phoenicis (Chagas 1973(Chagas , 1988) that provokes severe damages in hot and drought regions. It was observed at field conditions that 'IPR 99' presents resistance.
Some progenies of 'IPR 99' present complete resistance to rust (Sera et al. 2010b), but probably this resistance will be defeated by new rust races in a short time. The resistance to leaf rust is partial in many progenies (Sera et al. 2010a) and it may require chemical control, but with a lower number of fungicide applications in comparison with susceptible cultivars.
'IPR 99' presents a good level of partial resistance (moderate resistance) to the symptoms of necrosis and mummification of fruits (Sera et al. 2005). These symptoms are being associated with the attack of Colletotrichum spp. or Colletotrichum gloeosporioides Penz (Juliatti andSilva 2001, Paradela-Filho et al. 2001). These and others traits are described in Table 2.