The use of resistant cultivars is the most effective strategy for controlling coffee leaf rust caused by the fungus Hemileia vastatrix. To assist the development of such cultivars, amplified fragment-length polymorphism (AFLP) markers linked to two loci of coffee resistance to races I and II as well as pathotype 001 of H. vastatrix were converted to sequence-characterized amplified region (SCAR) and cleaved amplified polymorphic site (CAPS) markers. In total, 2 SCAR markers and 1 CAPS marker were validated in resistant and susceptible parents as well as in 247 individuals from the F2 population. The efficiency of these markers for marker-assisted selection (MAS) was evaluated in F2:3 and backcross (BCrs2) populations genotyped with the developed markers and phenotyped with race II of H. vastatrix. The markers showed 90% efficiency in MAS. Therefore, the developed markers, together with molecular markers associated with other rust resistance genes, were used for F3:4 and BCrs3 coffee selection. The selected plants were analyzed using two markers associated with coffee berry disease (CBD) resistance, aiming for preventive breeding. MAS of F3:4 and BCrs3 individuals with all resistance loci was feasible. Our phenotypic and genotypic approaches are useful for the development of coffee genotypes with multiple genes conferring resistance to coffee leaf rust and CBD.

The use of growth regulators in potato crop is an alternative to reduce the aerial growth of plants and redirects carbon assimilates and nutrients to the tubers. Therefore, the objective of this study was to evaluate the effects of growth regulators, paclobutrazol and trinexapac-ethyl on plant growth and changes on the anatomy of leaves of cultivar Markies in summer conditions of the southern region of Brazil. Potato plants cv. Markies were in the summer growing season of Southeast region of Brazil and 35 days after planting, the plants were sprayed with paclobutrazol (PBZ) at 0.125 and 0.250 L ha-1 and trinexapac-ethyl (TE) at 1.0 and 2.0 L ha-1. Treatment with PBZ at both doses reduced the height of potato plants, which resulted in higher index of leaf chlorophyll and reduced the content of starch and non-reducing sugars. Both PBZ and TE treated plants exhibited anatomical changes in the leaves, including larger epidermal cells and more elongated palisades cells. These data suggest that such changes in the anatomy of potato leaf in response to the use of PBZ directly influence leaf metabolism.

Floriculture is a promising activity and has great economic importance. In this context, the cultivation of Lilium pumilum Redouté stands out. However, one of the main challenges flower farmers face is that a large part of the products is lost before reaching the final consumer, due to postharvest losses. Such losses can be minimized by adopting some techniques, such as the use of conditioning solution (pulsing), which has been effective in preventing early senescence. In this sense, this study aimed to evaluate the effect of pulsing with sucrose, citric acid and silver thiosulphate on postharvest conservation of L. pumilum cut flowers. All treatments promoted a 1.8±0.3 day increase in longevity, uniformity of floral opening, and reduced fresh weight loss compared to the control (flowers that were not pulse-treated). There was no significant difference in chlorophyll content and leaf relative water content. The time of exposure to pulsing caused significant differences in the reduction of anthocyanin contents when compared to the control, demonstrating that pulsing preservative solution for at least 6 h extends the vase life of L. pumilum cut flowers by two days.

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