Abstract Brazil accounts for a large percentage of the world’s citrus production, with ‘Tahiti’ acid lime tree standing out among several cultivated species. However, its cultivation is supported by a very narrow genetic base, being composed of few scion and rootstock options. In this way, the aim of this study was to evaluate the vegetative development and production of twelve ‘Tahiti’ acid lime clones on two rootstocks. The experiment was carried out at Fazenda José Guarete, municipality of São Mateus – ES. A randomized block design was used in the split plot scheme, with plot consisting of two rootstocks and subplot of the twelve ‘Tahiti’ acid lime clones. Traits evaluated were: vegetative development, production and productive efficiency, internal and external quality of fruits. Bello Fruit, Iconha, BRS Passos, Itarana, Persian 58, CNPMF 5059 and Elédio clones were superior in terms of production, vegetative traits and fruit quality. ‘Swingle’ citrumelo rootstock showed higher values for vegetative traits compared to ‘Riverside’ citrandarin. The clone and rootstock combinations that provided better agronomic performance in this study were BRS Passos, Bello Fruit, Elédio and Iconha grafted on ‘Swingle’ citrumelo and CNPMF 5059, Iconha and Elédio grafted on ‘Riverside’ citrandarin.

Combining longitudinal data and statistical models from perennial crops enabled us to estimate the optimum number of measures (harvests), implying accurate discrimination of superior genotypes in those crops. Herein, the goal of this study was to determine the optimum number of harvests based on yield traits and recommend a superior graft/rootstock combination (GRC) for Citrus latifolia Tanaka. Twenty-four GRCs of 'Tahiti' acid lime were evaluated from July 2017 to August 2018 for fruit yield per plant (FYP), number of fruits per plant (NFP), and longitudinal (LFD) and transversal fruit diameter (TFD). The experimental design was a randomized complete block with 4 replications. The experimental unit consisted of three individuals, totalling 244 individuals. The GRCs were composed of (i) two hybrids that were used as rootstock, citrumelo ‘Swingle’ (Citrus paradisi x Poncirus trifoliata) and cintrandarin ‘Riverside’ (Citrus sunki x Poncirus trifoliata); and (ii) 12 different C. latifolia genotypes that were used as grafts: Bello Fruit, Eledio, Iconha, Itarana, Santa Rosa, Bearss lime, CNPMF 01, CNPMF 02, CNPMF 2001, CNPMF 5059, BRS Passos, and Persian 58. Mixed models were employed to estimate the variance components. The optimum number of harvests was determined based on selective efficiency values above 0.9. The estimated repeatability coefficients presented values of 0.14 (LFD), 0.16 (TFD), 0.36 (FYP), and 0.38 (NFD). Based on the results, four harvests were able to choose genotypes based on FYP and NFP, whereas LFD and TFD were considered inefficient traits for recommending superior GRCs.

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The objective of this study was to determine a suitable plot size for field experiments with papaya genotypes. Two experiments were carried out using a randomized complete block design with 11 and 12 papaya genotypes, respectively. In both experiments, plots consisted of one row, with 10 plants each. Spacing between rows was 3.5 m, with 1.5 m between plants. The characteristic evaluated was fruit production in t ha -1 in first year of cultivation, and the basic unit used was one plant. Suitable plot size was estimated using Lin and Binns, and Hatheway's methods. These methods are complementary and should be used together in the determination of the optimum plot size. The results of these tests showed that the optimum plot size for the evaluation of yield in papaya was four plants by plot with four replications each assuming 30% of the precision for establishing differences among the means of two genotypes.

Genetic diversity studies provide fundamental information for characterization, conservation and utilization of available genetic resources in plant genetic improvement programs. To evaluate the genetic divergence among papaya accessions, 17 morphoagronomic variables from 59 accessions of the active germplasm bank were evaluated in an experiment at Santa Teresinha Farm, belonging to Caliman Agrícola S/A, in Linhares-ES, Brazil. The experiment was conducted in a randomized block design with two replicates. The divergence between the accessions was estimated using the Tocher optimization method and the agglomerative hierarchical approach based on the Unweighted Pair-Group Method Using an Arithmetic Average. (UPGMA). There was significant difference for all the variables evaluated, showing variability among the accessions. The variables plant height, first fruit insertion height, greatest thickness of fruit pulp, fruit diameter, and fruit length had heritability above 80%, indicating expressive gains in the simple process of selection. Genetic variability was found among the accessions, and Americano, short-peduncle-STZ-03 and Califlora 209 were the most divergent. The optimization methods Tocher and hierarchical based on UPGMA were partially concordant for the formation of heterotic groups of papaya accessions. The variables fruit mass, fruit diameter and plant height contributed the most to the genetic diversity.

Objetivou-se com este trabalho avaliar a influência das condições de armazenamento de sementes de aroeira, na longevidade durante 4 meses. O experimento foi instalado em delineamento inteiramente casualizado, com tratamentos sob arranjo fatorial (2 x 5), correspondendo respectivamente às duas condições de armazenamento (ambiente e geladeira) e aos cinco períodos de armazenamento, ao qual inclui também as sementes recém-colhidas. Foram utilizadas 4 repetições de 50 sementes por tratamento e a germinação avaliada durante 15 dias, em cada mês. Para o ensaio foram utilizadas sementes extraídas de frutos maduros que foram acondicionadas em embalagens de vidro vedados com tampa emborrachada e mantidos em duas condições distintas de temperatura (geladeira a 10 ºC e condições de laboratório a 25 ºC) por 4 meses. Para verificar a viabilidade das sementes, efetuou-se o teste de germinação, sendo a semeadura feita em papel mata-borrão, em caixas gerbox mantidas em câmara de germinação, sob temperatura alternada de 20-30ºC com fotoperíodo de 8-16 horas de luz e escuro, respectivamente. Neste período avaliou-se a porcentagem de germinação, o Índice de velocidade de germinação (IVG), e a porcentagem de plântulas normais e anormais. O armazenamento em condições de geladeira foi mais eficiente para manutenção da qualidade fisiológica das sementes de aroeira-vermelha, podendo estas ser armazenadas por um período de até 4 meses. Recomenda-se não armazenar sementes de aroeira em condições de laboratório por mais de 60 dias.Palavras-chave: Schinus terebinthifolius. Longevidade. Temperatura. PHYSIOLOGICAL QUALITY OF AROEIRA SEEDS UNDER THE STORAGE CONDITIONS SUMMARY:The objective of this work was to evaluate the influence of the storage conditions of aroeira seeds on longevity for 4 months. The experiment was carried out in a completely randomized design with treatments in a factorial arrangement (2 x 5), corresponding respectively to the two storage conditions (ambient and refrigerator) and five periods of storage, which also includes the newly harvested seeds. Four replicates of 50 seeds per treatment were used and the germination was evaluated during 15 days, in each month. To test the seeds extracted from mature fruits were used which were placed in glass containers sealed with rubberized lid and kept at two different temperature conditions (10 ° C and a refrigerator at laboratory conditions at 25 ° C) for 4 months. To check the viability of seed, made up germination test, sowing being performed in blotting paper in gerboxes maintained in a growth chamber under alternating temperature to 20-300ºC for 8-16 hours photoperiod light and dark, respectively. During this period the percentage of germination, germination speed index (IVG), and percentage of normal and abnormal seedlings were evaluated. The storage under refrigerator conditions was more efficient for the maintenance of the physiological quality of the seeds of aroeira-red, and these could be stored for a period of up to 4 months. It is recommended not to store aroeira see...

The aim of this study was to select the most suitable model for leaf area estimation from papaya seedlings cv. ‘Golden THB’ using linear dimensions of leaves with unilobular and trilobular morphology. It was used leaves of 60 seedlings with 30 days after sowing produced in nursery of the Fazenda Santa Teresinha which belongs to company Caliman Agrícola S.A., in the municipality of Linhares, state of Espírito Santo, in March 2016. The measurement of the length (L) was performed along the midrib, the maximum width (W) of the leaf blade, the product of the length by the width (LW) and the observed leaf area (OLA). From these results, first degree and power linear regression models was adjusted. From the proposed regression models, the validation was performed with a leaves sample of 60 seedlings produced in June 2016, obtaining, thus, the estimated leaf area (ELA). The following criteria were used to choose the best model: the highest coefficient of determination (R2), the values do not significant of the comparison of means of OLA and ELA and values of MAE and RMSE closer to zero. The leaf area estimation from papaya seedlings cv. ‘Golden THB’ can be represented through equation ELA = -0.402619 + 0.612525(LW) for trilobular leaves and through equation ELA = 0.623355 + 0.610552(LW) for unilobular leaves.

Understanding the genetic diversity and overcoming genotype-by-environment interaction issues is an essential step in breeding programs that aims to improve the performance of desirable traits. This study estimated genetic diversity and applied genotype + genotype-by-environment (GGE) biplot analyses in cotton genotypes. Twelve genotypes were evaluated for fiber yield, fiber length, fiber strength, and micronaire. Estimation of variance components and genetic parameters was made through restricted maximum likelihood and the prediction of genotypic values was made through best linear unbiased prediction. The modified Tocher and principal component analysis (PCA) methods, were used to quantify genetic diversity among genotypes. GGE biplot was performed to find the best genotypes regarding adaptability and stability. The Tocher technique and PCA allowed for the formation of clusters of similar genotypes based on a multivariate framework. The GGE biplot indicated that the genotypes IMACV 690 and IMA08 WS were highly adaptable and stable for the main traits in cotton. The cross between the genotype IMACV 690 and IMA08 WS is the most recommended to increase the performance of the main traits in cotton crops.