In this review of coffee leaf rust (CLR) in Brazil, we report: (i) the historical introduction of CLR in Brazil and the first control measures; (ii) favorable environmental conditions and times of year for the disease; (iii) breeding methods and strategies used for developing CLR-resistant cultivars; (iv) the levels, sources, and types of CLR resistance; (v) the development of Brazilian resistant cultivars; and (vi) chemical and cultural control methods. Most plantations are cultivated with susceptible cultivars, such as those of the Catuaí and Mundo Novo groups. Brazilian research institutes have developed dozens of cultivars with different levels of resistance, and significantly increased the planting of new resistant cultivars. The main sources of CLR resistance are genotypes from Híbrido de Timor, Icatu, BA series carrying the SH3 gene, and Ethiopian wild coffees. High CLR resistance is still observed in Sarchimor and SH3-carrying genotypes. Intermediate CLR resistance is observed in Ethiopian wild coffees and in Sarchimor and Icatu derivatives, where qualitative resistance has been supplanted by races of Hemileia vastatrix. Contact, mesostemic, and systemic fungicides are used for chemical control in Brazil. CLR incidence in Brazil begins to increase after the rainy season onset in November, reaches a peak in June, and remains high until August. Thus, chemical control is typically applied from December to April.

The aim of this study was to quantify NH3-N losses from conventional, stabilized, slow-release, and controlled-release N fertilizers in a coffee field. The N fertilizers analyzed were prilled urea, prilled urea dissolved in water, ammonium sulfate (AS), ammonium nitrate (AN), urea + Cu + B, urea + adhesive + CaCO3, and urea + NBPT (all with three split applications), as well as blended N fertilizer, urea + elastic resin, urea-formaldehyde, and urea + polyurethane (all applied only once). NH3-N losses (mean of two crop seasons) were statistically higher for urea + adhesive + CaCO3 (27.9% of applied N) in comparison with the other treatments. Loss from prilled urea (23.7%) was less than from urea + adhesive + CaCO3. Losses from urea + NBPT (14.5%) and urea + Cu + B (13.5%) were similar and lower than those from prilled urea. Urea dissolved in water (4.2%) had even lower losses than those treatments, and the lowest losses were observed for AS (0.6%) and AN (0.5%). For the single application fertilizers, higher losses occurred for urea + elastic resin (5.8%), blended N fertilizer (5.5%), and urea + polyurethane (5.2%); and urea-formaldehyde had a lower loss (0.5%). Except for urea + adhesive + CaCO3, all N-fertilizer technologies reduced NH3-N losses compared to prilled urea.

<p class="western" style="margin-bottom: 0cm; line-height: 200%;" align="JUSTIFY"><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;">Vegetative propagation of arabica coffee plants selected by their agronomic value has been accomplished, routinely, for scientific purposes, through somatic embryogenesis and rooting of stem cuttings, in Brazil. Somatic embryogenesis is the election method when a very high number of cloned plants is demanded. Nevertheless, the costs of </span></span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;"><em>in vitro</em></span></span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;"> multiplication make difficult to explore it commercially. The experiments described herein aimed to amplify the number of </span></span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;"><em>in </em></span></span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;"><span lang="en-GB"><em>vitro</em></span></span></span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;"> cloned plants</span></span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;"><em>,</em></span></span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;"> post acclimatization, to reduce costs. Different concentrations of an auxin translocation inhibitor and its association with a cytokinin were applied, as successive pulses, in the 3</span></span></span><span style="color: #000000;">^{<span style="font-family: Times New Roman, serif;"><span style="font-size: medium;">rd</span></span>}</span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;">, 8</span></span></span><span style="color: #000000;">^{<span style="font-family: Times New Roman, serif;"><span style="font-size: medium;">th</span></span>}</span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;"> and 13</span></span></span><span style="color: #000000;">^{<span style="font-family: Times New Roman, serif;"><span style="font-size: medium;">th</span></span>}</span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;"> months after transference to the greenhouse, on the same sets of Catucaí and Siriema </span></span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;"><em>in vitro</em></span></span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;"> cloned plants,</span></span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;">to induce sprouting.</span></span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;"> At the 8</span></span></span><span style="color: #000000;">^{<span style="font-family: Times New Roman, serif;"><span style="font-size: medium;">th </span></span>}</span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;">month, the experiments with </span></span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;"><em>in vitro</em></span></span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;"> cloned Catucaí plants were reproduced in the nursery, for comparison. Best results were observed for the association 2,3,5-triiodobenzoic acid (TIBA) 1000 + benzylaminopurine 60 mg.mL</span></span></span><span style="color: #000000;">^{<span style="font-family: Times New Roman, serif;"><span style="font-size: medium;">-1</span></span>}</span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;"> applied in the greenhouse, at the 13</span></span></span><span style="color: #000000;">^{<span style="font-family: Times New Roman, serif;"><span style="font-size: medium;">th</span></span>}</span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;"> month, when 8.5 and 7.0 micro-cuttings above 1 cm in length were produced using sprouts taken from each Catucaí and Siriema acclimatized plant, respectively. Applying this treatment twice a year, and harvesting induced sprouts each six months after the induction treatments, approximately 15 plants per each acclimatized one can be produced. The most important effect of TIBA was the induction of sub-apical sprouting. Greenhouse would be the best environment to apply successive pulses of sprouting inducers to coffee </span></span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;"><em>in vitro </em></span></span></span><span style="color: #000000;"><span style="font-family: Times New Roman, serif;"><span style="font-size: medium;">cloned plants.</span></span></span></p><p class="western" style="margin-bottom: 0cm; line-height: 200%;" align="JUSTIFY"> </p>