The introduction of genes from wild species is a practice little adopted by breeders for the improvement of commercial crops, although it represents an excellent opportunity to enrich the genetic basis and create new cultivars. In peanut, this practice is being increasingly adopted. In this study we present results of introgression of wild alleles from the wild species Arachis duranensis and A. batizocoi improving photosynthetic traits and yield in a set of lines derived from the cross of an induced allotetraploid and cultivated peanut with selection under water stress. The assays were carried out in greenhouse and field focusing on physiological and agronomic traits. A multivariate model (UPGMA) was adopted in order to classify drought tolerant lines. Several lines showed improved levels of tolerance, with values similar to or greater than the tolerant control. Two BC1F6 lines (53 P4 and 96 P9) were highlighted for good drought-related traits, earliness and pod yield, having better phenotypic profile to the drought tolerant elite commercial cultivar BR1. These lines are good candidates for the creation of peanut cultivars suitable for production in semiarid environments.

RESUMO: O objetivo desse trabalho foi avaliar seis genótipos de milho com características promissoras para a produção de minimilho e adaptados à região da Zona da Mata de Pernambuco, região Nordeste do Brasil. O experimento foi conduzido no campus experimental da Fitotecnia na UFRPE, entre 2014/2015. Foram avaliados seis genótipos, quanto a dez variáveis agronômicas. Na análise de variância pode ser observado que as variáveis significativas para produção do minimilho foram: número de espigas, início para a diferenciação da panícula, altura da planta aos 30 dias após a emergência, peso da espiga e peso da parte aérea. As correlações genotípicas foram mais elevadas do que as fenotípicas, porém de mesmo sinal, indicando menor influência do ambiente na expressão dos caracteres. Na análise de trilha ficou demonstrado que mais de 96% (R 2 ) de influência das variáveis sobre número de espigas e com um baixo efeito residual 0,17, confirmando que as variáveis analisadas influenciam na produção do número de espigas do minimilho. Os caracteres mais importantes na determinação direta da produção do minimilho foram: altura de planta aos 30 e 60 dias após a emergência, peso de espigas e peso da parte aérea. Recomenda-se a utilização dos genótipos CMS47, CMS39 e AL-25 para futuros trabalhos de melhoramento.ABSTRACT: Six corn genotypes with promising characteristics for the production of mini-corn and adapted to the Zona da Mata region, Pernambuco, Brazil, were evaluated. The experiment was performed at the Phytotechnical Experimental Campus of the UFRPE, between 2014 and 2015. Six genotypes were evaluated for ten agronomic variables. Variance analysis revealed that the significant variables for mini-corn production were: number of spikes, differentiation panicle start, height of plant after 30 days of emergence, weight of spike and weight of aerial segment. Genotype co-relationships were higher than the phenotype ones, albeit of the same sign. This fact showed a smaller influence of the environment on the characteristics. Trail analysis revealed more than 96% (R2) of the variables´ influence on the number of spikes and low residual effect 0.17, confirming that variables affected the production of the number of spikes of mini-corn. The most important characteristics in the direct determination of mini-corn production were plant height at 30 and 60 days after emergence, spike weight and weight of the aerial segment. The use of genotypes CMS47, CMS39 and AL-25 is recommended for further improvement research work.

Ramulosis (Colletotrichum gossypii South var. cephalosporioides Costa) is a fungal disease of cotton (Gossypium hirsutum L.) that causes damage to leaves, stems, and bolls by reducing fiber production; it can be controlled by chemical fungicides. Geraniol is a monoterpenoid produced by some aromatic plant species whose fungicidal properties have been widely reported. Geraniol synthase (GES; EC 3.1.7.11) is the precursor enzyme involved in the biosynthetic chain of geraniol. Geraniol synthase (ges) gene transcripts were prospected in 11 aromatic species with molecular and phytopathological tools to identify promising accessions for further use in in vitro and in vivo assays involving the control of cotton ramulosis. Mentha pulegium L. oil highly expressed ges and inhibited fungal growth at 1000 μL L-1 in an in vitro assay. Validation assays were carried out in two environments and M. pulegium at 2000 μL L-1 reduced the initial and final severity indices of the disease to 48% and 52%, respectively, in preventive treatments; in curative assays, indices were 44% and 54%, respectively. This indicates that it is a promising bioactive compound to control cotton ramulosis.

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