Leaf-level carbon isotope discrimination and its relationship with yield components as a tool for cotton phenotyping in unfavorable conditions.

The initial goal of this study was to measure the efficiency of carbon isotope discrimination (?) in distinguishing between cotton plant genotypes subjected to two water regimes. In addition, ? measurements, leaf water potential and gas exchange ratios were monitored. Using Brazilian breeding lines, this study also tested the usability of ? as a proxy for selecting high-performing yield components in cotton plants grown in unfavorable conditions, particularly water deficiency. For these experiments, ? and yield components were measured and their correlations analyzed. Differences among cotton genotypes for ? (p < 0.0001) were verified, and it was found that this variable was significantly correlated with gas exchange. There was a significant positive correlation between ? and seed cotton yield only in the site experiencing severe water deficiency (Santa Helena de Goiás). However, ? had a significant negative correlation with fiber percentage. Our results indicate that ? is a suitable tool for cotton phenotyping, and it may be applied in cotton breeding programs that aim to produce high-performing yield components in unfavorable conditions

Identificação de cromossomo artificial de bactéria contendo gene de resistência a doenças em cafeeiro.

O estudo e a caracterização de fatores genéticos de resistência são importantes para ampliar os conhecimentos da interação planta-patógeno. O marcador molecular CARF 005, identificado em trabalho anterior, é capaz de identificar um fragmento de gene de resistência a doenças presente em genótipos de cafeeiro resistentes a ferrugem, principal doença da cultura. Neste trabalho, o CARF 005 foi utilizado para fazer o screening de uma biblioteca BAC de Coffea arabica com 56.832 clones. Foram identificados dois clones contendo o fragmento do gene de resistência. Após o sequenciamento, esses poderão ser usados para estudo da estrutura do gene e, eventualmente, em obtenção de plantas transgênicas para auxiliar programas de melhoramento

High-density genetic mapping for coffee leaf rust resistance.

Coffee leaf rust caused by the fungus Hemileia vastatrix causes considerable economic losses for coffee producers. Although agrochemical products can provide sufficient disease control, the use of resistant cultivars is a safer alternative. This resistance may be constrained by one or a few genetic factors, mainly those found in material originating from interspecific hybrids. In this study, the genetic analysis of an F2 population consisting of 224 plants derived from a crossing of Híbrido de Timor UFV 427-15 (resistant) with Catuaí Amarelo IAC 30 (susceptible) showed that a dominant gene confers the resistance of coffee to race II of H. vastatrix. From a genetic map saturated with 25 amplified fragment length polymorphism (AFLP) markers linked to the resistance gene, we developed a high-density genetic map with six sequence-characterized amplified region (SCAR) markers delimiting a chromosomal region of 9.45 cM and flanking the dominant gene at 0.7 and 0.9 cM. This is the first saturated and high-density genetic map obtained from this region containing the resistance gene. The results of this study are of great importance for the introduction of molecular markers for marker-assisted selection; they will also facilitate studies related to the cloning, structure, and function of race-specific genes involved in the resistance of coffee trees to H. vastatrix

Mapeamento genético de marcadores AFLP ligados ao gene de resistência do híbrido de timor à Hemileia vastatrix.

A ferrugem alaranjada do cafeeiro causada por Hemileia vastatrix é tida como a mais devastadora doença do cafeeiro. Este trabalho objetivou estudar a herança gênica e a identificação de marcadores moleculares ligados ao gene que confere resistência a esta doença. Para este estudo foram utilizados a população F2 (160 indivíduos), o retrocruzamento resistente (RCr, 20 indivíduos) e o suscetível (RCs, 135 indivíduos), derivados do cruzamento entre o Híbrido de Timor UFV 427-15, genitor resistente e o suscetível Catuai amarelo UFV 2143-236. A análise da segregação das populações, em estudo, indicou que um único gene dominante, presente no acesso do Híbrido de Timor UFV 427-15, é responsável pela resistência. Foram utilizadas as metodologias de BSA (Bulked Segregant Analysis) e AFLP, e analisadas 852 combinações de primers, que permitiram identificar três marcadores ligados ao gene de resistência localizados flanqueando ambos os lados, e distantes a 8.69, 20.50 e 25.10 cM. Estes são os primeiros marcadores identificados para o gene de resistência a ferrugem presente no Híbrido de Timor, e auxiliarão na seleção em programas de melhoramento para a resistência a ferrugem no Brasil

The Effect of Goal Orientation to the Academic Performance in Mathematics of Grade 10 Students

Mathematics is a multifaceted activity; it has a lot of faces, even those one we can’t notice. Each facet is worth it to deal with so that every individual will be prepared for their future. It provides us with something to walk through difficulties. It is beneficial to set a goal for each individual, whether it is a short-term goal, long-term goal, or even the goal that falls in the middle. Setting a goal has been used extensively in a variety of ways, even on the outside of the school or in any settings. It could possibly bring you a positive achievement if follows correctly. The main purpose of this study was to determine if the goal orientation of the grade 10 students of one school in Region IV-A (CALABARZON) Rizal has a significant effect to their academic performance. As regards to the data of the significant effect of goal orientation to the academic performance of grade 10 students, the p-value of less than 0.001 revealed that the task goal orientation of the respondents has a significant effect to their academic performance in mathematics. The p-value of 0.007 implied that the ego goal orientation of the respondents has also had a significant effect on their academic performance in mathematics. Therefore, the researchers concluded that there is a significant effect of the respondents’ goal orientation, although the effect is very low and low, respectively. For the betterment, it is advised that researchers conducting a comparable study on goal orientation expand their scope to include student study habits, which may be influenced by a variety of circumstances

The Effect of Goal Orientation to the Academic Performance in Mathematics of Grade 10 Students

Mathematics is a multifaceted activity; it has a lot of faces, even those one we can’t notice. Each facet is worth it to deal with so that every individual will be prepared for their future. It provides us with something to walk through difficulties. It is beneficial to set a goal for each individual, whether it is a short-term goal, long-term goal, or even the goal that falls in the middle. Setting a goal has been used extensively in a variety of ways, even on the outside of the school or in any settings. It could possibly bring you a positive achievement if follows correctly. The main purpose of this study was to determine if the goal orientation of the grade 10 students of one school in Region IV-A (CALABARZON) Rizal has a significant effect to their academic performance. As regards to the data of the significant effect of goal orientation to the academic performance of grade 10 students, the p-value of less than 0.001 revealed that the task goal orientation of the respondents has a significant effect to their academic performance in mathematics. The p-value of 0.007 implied that the ego goal orientation of the respondents has also had a significant effect on their academic performance in mathematics. Therefore, the researchers concluded that there is a significant effect of the respondents’ goal orientation, although the effect is very low and low, respectively. For the betterment, it is advised that researchers conducting a comparable study on goal orientation expand their scope to include student study habits, which may be influenced by a variety of circumstances

Carbon isotope fractionation for cotton genotype selection.

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