Heterogeneity of linalool chemotypes of Lippia alba (Mill.) N.E.Br., based on clonal half-sib progenies

Lippia alba (Mill.) N.E.Br. is an aromatic and medicinal shrub native to the American continent. Despite its potential as a source of essential oil for the pharmaceutical and cosmetics industries, few selection and genetic improvement studies have been carried out. The aim of this study was to provide genetic information on this species for breeding programs, showing its selection potential, by investigating clonal half-sib progenies. The following characteristics were evaluated per plant: leaf dry mass (LDM), total dry mass (TDM), leaf yield (LY), essential oil yield (EOY) and oil production (OP). Estimates were made for the several genetic parameters including absolute genetic gain at 30% selection intensity, correlations and relative contribution of additive and environmental effects to phenotypic correlation. Two experimental trials on 30 progenies were conducted: one in Campinas, state of São Paulo (SP), Brazil, with two harvests of the aerial part, and one in Monte Alegre do Sul, SP, Brazil, with only one harvest. The trials were conducted in a randomized block design consisting of subplots with three replications, each plot (progeny) consisting of 8 to 15 clonally-replicated plants with subplot harvesting. Variations were detected between progenies and harvests, as well as progeny/harvest interactions in the split plot experiment. High heritability and genetic gains were obtained at both sites for LDM, TDM and OP. The lowest variations among progenies were obtained for LY and EOY, highlighting selection problems. Negative additive genetic correlations were obtained for EOY × LDM, EOY × TDM, LY × TDM and LY × LDM. Selection for LDM resulted in increased oil production per plant (OP), even where there was a negative correlation between LDM × EOY

PELLETS MADE FROM PLANT STRUCTURES AND ESSENTIAL OIL OBTAINED FROM LEAVES OF Ageratum conyzoides L. AFFECTING THE DEVELOPMENT OF Sitophilus oryzae PELLETS PRODUZIDOS COM ESTRUTURAS DE PLANTAS E ÓLEO ESSENCIAL DE FOLHAS DE Ageratum conyzoides L. AFETANDO O DESENVOLVIMENTO DE Sitophilus oryzae

<!-- @page { margin: 2cm } P { margin-bottom: 0.21cm } --> <p style="margin-bottom: 0cm; font-style: normal; font-weight: normal; line-height: 120%; text-decoration: none;" lang="pt-BR" align="JUSTIFY"><span style="color: #000000;"><span style="font-family: Times New Roman,serif;"><span style="font-size: x-small;"><span style="font-style: normal;"><span style="color: #000000;"><span style="text-decoration: none;"><span style="font-family: Times New Roman,serif;"><span style="font-size: small;"><span lang="pt-BR"><span style="font-style: normal;"><span style="font-weight: normal;">The objectives of this study were to evaluate the effect of pellets, made from either vegetative and reproductive plant structures powder or essential oil obtained from leaves of billy goat weed, on the development of </span></span></span></span></span></span></span></span><span style="font-style: normal;"><span style="color: #000000;"><span style="text-decoration: none;"><span style="font-family: Times New Roman,serif;"><span style="font-size: small;"><span lang="pt-BR"><em><span style="font-weight: normal;">Sitophilus oryzae </span></em></span></span></span></span></span></span><span style="font-style: normal;"><span style="color: #000000;"><span style="text-decoration: none;"><span style="font-family: Times New Roman,serif;"><span style="font-size: small;"><span lang="pt-BR"><span style="font-style: normal;"><span style="font-weight: normal;">(L., 1763) (Coleoptera: Curculionidae), as well as to determine the period in which they could be stored without losing their insecticidal action. Pellets made from powders of different billy goat weed structures (root, leaf, inflorescence, and seeds) were stored for 2, 60, 120, and 180 days, and those made from essential oil were stored for 2 and 60 days. The billy goat weed presents insecticidal activity on </span></span></span></span></span></span></span></span><span style="font-style: normal;"><span style="color: #000000;"><span style="text-decoration: none;"><span style="font-family: Times New Roman,serif;"><span style="font-size: small;"><span lang="pt-BR"><em><span style="font-weight: normal;">S. oryzae</span></em></span></span></span></span></span></span><span style="font-style: normal;"><span style="color: #000000;"><span style="text-decoration: none;"><span style="font-family: Times New Roman,serif;"><span style="font-size: small;"><span lang="pt-BR"><span style="font-style: normal;"><span style="font-weight: normal;">, depending on the plant structure and concentration in the pellet. Pellets made from leaves and seeds, at the concentration of 0.5%, provided a better </span></span></span></span></span></span></span></span><span style="font-style: normal;"><span style="color: #000000;"><span style="text-decoration: none;"><span style="font-family: Times New Roman,serif;"><span style="font-size: small;"><span lang="pt-BR"><em><span style="font-weight: normal;">S. oryzae </span></em></span></span></span></span></span></span><span style="font-style: normal;"><span style="color: #000000;"><span style="text-decoration: none;"><span style="font-family: Times New Roman,serif;"><span style="font-size: small;"><span lang="pt-BR"><span style="font-style: normal;"><span style="font-weight: normal;">control, affecting more the emergence of insects than their development cycle. Pellets made from any plant structure, except for root, at 5.0%, can be stored for up to 180 days without losing their insecticidal action, while, at 0.5%, the storage period should be less than 60 days. Pellets made from essential oil of billy goat weed leaves can not be stored under uncontrolled conditions and reduce the </span></span></span></span></span></span></span></span><span style="font-style: normal;"><span style="color: #000000;"><span style="text-decoration: none;"><span style="font-family: Times New Roman,serif;"><span style="font-size: small;"><span lang="pt-BR"><em><span style="font-weight: normal;">S. oryzae</span></em></span></span></span></span></span></span><span style="font-style: normal;"><span style="color: #000000;"><span style="text-decoration: none;"><span style="font-family: Times New Roman,serif;"><span style="font-size: small;"><span lang="pt-BR"><span style="font-style: normal;"><span style="font-weight: normal;"> population, but do not eliminate it, at concentrations of up to 0.5 µg L</span></span></span></span></span></span></span></span><span style="font-style: normal;"><span style="color: #000000;"><span style="text-decoration: none;"><sup><span style="font-family: Times New Roman,serif;"><span style="font-size: small;"><span lang="pt-BR"><span style="font-style: normal;"><span style="font-weight: normal;">-1</span></span></span></span></span></sup></span></span></span><span style="font-style: normal;"><span style="color: #000000;"><span style="text-decoration: none;"><span style="font-family: Times New Roman,serif;"><span style="font-size: small;"><span lang="pt-BR"><span style="font-style: normal;"><span style="font-weight: normal;">. </span></span></span></span></span></span></span></span></span></span></span></p> <p style="margin-bottom: 0cm; font-style: normal; font-weight: normal; line-height: 120%; text-decoration: none;" lang="en-US" align="JUSTIFY"><span style="color: #000000;"><span style="font-family: Times New Roman,serif;"><span style="font-size: small;">KEY-WORDS:<strong> </strong>Insecta; biopesticide plant; weevil; billy goat weed.</span></span></span></p><!-- @page { margin: 2cm } P { margin-bottom: 0.21cm } --> <p style="margin-bottom: 0cm; font-style: normal; font-weight: normal; line-height: 120%; text-decoration: none;" lang="pt-BR" align="JUSTIFY"><span style="color: #000000;"><span style="font-family: Times New Roman,serif;"><span style="font-size: small;">Os objetivos do trabalho foram avaliar o efeito de <em>pellets</em> produzidos com pós de estruturas vegetativa e reprodutiva de plantas e com o óleo essencial obtido de folha de<em> </em>mentrasto, no desenvolvimento de <em>Sitophilus oryzae </em>(L., 1763) (Coleoptera: Curculionidae) e determinar o tempo máximo de armazenamento dos <em>pellets.</em> Os <em>pellets </em>produzidos com os pós das estruturas de mentrasto (raiz, folha, inflorescência e semente) foram armazenados por 2, 60, 120 e 180 dias e os com óleo essencial por 2 e 60 dias. O mentrasto apresenta ação inseticida em <em>S. oryzae</em>, dependendo da estrutura da planta e da concentração no <em>pellet. Pellets </em>produzidos com os pós de folha e de sementes, na concentração de 0,5%, controlam <em>S. oryzae</em>,<em> </em>afetando mais a emergência de insetos que sua fase imatura. <em>Pellets</em> na concentração de 5,0%, produzidos com pós de quaisquer das estruturas de mentrasto, exceto raiz, podem ser armazenados até 180 dias. Na concentração de 0,5%, o período de armazenamento deve ser inferior a 60 dias. <em>Pellets</em> produzidos a partir de óleo essencial obtido de folha de mentrasto não podem ser armazenados em condições ambientes e reduzem a população de<em> S. oryzae, </em>mas não a eliminam, quando em concentração de até 0,5 µg L<sup>-1</sup>.</span></span></span></p> <p style="margin-bottom: 0cm; font-style: normal; font-weight: normal; line-height: 120%; text-decoration: none;" lang="pt-BR" align="JUSTIFY"><span style="color: #000000;"><span style="font-family: Times New Roman,serif;"><span style="font-size: small;"><span style="font-style: normal;"><span style="font-size: small;"><span style="font-weight: normal;">PALAVRAS-CHAVES: Insecta; planta inseticida; gorgulho; mentrasto.</span></span></span></span></span></span></p&gt

Heterogeneity of linalool chemotypes of L. alba Heterogeneity of linalool chemotypes of Lippia alba (Mill.) N.E.Br., based on clonal half-sib progenies

ABSTRACT: Lippia alba (Mill.) N.E.Br. is an aromatic and medicinal shrub native to the American continent. Despite its potential as a source of essential oil for the pharmaceutical and cosmetics industries, few selection and genetic improvement studies have been carried out. The aim of this study was to provide genetic information on this species for breeding programs, showing its selection potential, by investigating clonal half-sib progenies. The following characteristics were evaluated per plant: leaf dry mass (LDM), total dry mass (TDM), leaf yield (LY), essential oil yield (EOY) and oil production (OP). Estimates were made for the several genetic parameters including absolute genetic gain at 30% selection intensity, correlations and relative contribution of additive and environmental effects to phenotypic correlation. Two experimental trials on 30 progenies were conducted: one in Campinas, state of São Paulo (SP), Brazil, with two harvests of the aerial part, and one in Monte Alegre do Sul, SP, Brazil, with only one harvest. The trials were conducted in a randomized block design consisting of subplots with three replications, each plot (progeny) consisting of 8 to 15 clonally-replicated plants with subplot harvesting. Variations were detected between progenies and harvests, as well as progeny/harvest interactions in the split plot experiment. High heritability and genetic gains were obtained at both sites for LDM, TDM and OP. The lowest variations among progenies were obtained for LY and EOY, highlighting selection problems. Negative additive genetic correlations were obtained for EOY × LDM, EOY × TDM, LY × TDM and LY × LDM. Selection for LDM resulted in increased oil production per plant (OP), even where there was a negative correlation between LDM × EOY