The objectives of the present study were to assess the population structure and genetic diversity in traditional sweet cassava cultivars collected in Bbackyard^cultivations in the municipalities of Maringá, Cianorte, and Toledo, State of Paraná, Southern Brazil, using 13 SSR molecular markers. All the loci analyzed were considered polymorphic with a mean of 3.15 alleles per locus; the mean polymorphism information content (PIC) value found was 0.4598, indicating that the primers were reasonably informative and the heterozygosity amplitude observed ranged from 0.0270 (GA134) to 0.8718 (SSRY45), with a mean of 0.4762, while the mean genetic diversity obtained was 0.5407, ranging from 0.3138 (GA21) to 0.6502 (GA140). The most divergent combinations were BGM434T-BGM20M, BGM35C-BGM20M, BGM430T-BGM232M, BGM430T-BGM164M, BGM430T-BGM322M, and BGM35C-BGM164M. The analysis of population structure distributed the traditional cultivars assessed in four different groups. The analysis of molecular variance (AMOVA) estimated that 11, 15, and 74 % of the variance were between groups, between individuals within groups, and between individuals within the population as a whole, respectively. The F is (0.170) and F it (0.259) values indicated a number of heterozygotes present in the population under study lower than that necessary to reach the Hardy-Weinberg equilibrium. The genetic variability found among the traditional sweet cassava cultivars assessed was considered wide, and the groups that were most distant were mostly cultivars from Toledo and Maringá.

Evaluation of the stability and adaptability of genotypes across different environment conditions is important for release and recommendation of new varieties to ensure their high adaptability. Plant breeders evaluate germplasms in multi-environment trials to study the stability and adaptability of genotypes (G) and to recommend the genotypes to different environments (E). Multienvironment trials for 11 genotypes including 4 check varieties of cotton were carried out during 3 seasons in 3 locations in Mozambique. The objective of this study was to assess the G x E pattern and to evaluate the stability and adaptability of seed cotton yield of a new germplasm in Mozambique. The experiment was set up in Namialo (district of Meconta province of Nampula), Namara (district of Balama, province of Cabo Delgado) and Nhamatanda (district of Nhamatanda province of Sofala). The treatments consisted of 11 varieties, which were established in a randomized complete block design with four replications. The graphic analysis of additive main effect and multiplicative interaction (AMMI) were used to understand the G x E interaction pattern and to study the stability and adaptability. The results showed significant effect of genotype, environment and G x E interaction. The first two principal components explained about 80% of the detected interaction. The pair of Environment/Genotype showed the E/G combination for high performance. The genotypes and environments showed genetic and environmental performance dissimilarity. The AMMI revealed that genotypes FK 37, BA 919 and Flash were the most adaptable, while BA 2018 and BA 320 were the most stable across the variation of environments. Keywords: AMMI, Biplot, GGE, genotype x environment interaction, seed cotton yield. Abbreviations:AMMI_Additive main effect and multiplicative interaction; GE_Genotype by Environment interaction; GGE_ Genotype main effect plus genotype by environment interaction; GOT_Ginning out-turn; PCA_Principal component analysis.

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In many agricultural areas, crop production has decreased due to a lack of water availability, which is having a negative impact on sustainability and putting food security at risk. In plants, the plasticity of the root system architecture (RSA) is considered to be a key trait driving the modification of the growth and structure of roots in response to water deficits. The purpose of this study was to examine the plasticity of the RSA traits (mean root diameter, MRD; root volume, RV; root length, RL; and root surface area, SA) associated with drought tolerance in eight Lagenaria siceraria (Mol. Standl) genotypes, representing three different geographical origins: South Africa (BG-58, BG-78, and GC), Asia (Philippines and South Korea), and Chile (Illapel, Chepica, and Osorno). The RSA changes were evaluated at four substrate depths (from 0 to 40 cm). Bottle gourd genotypes were grown in 20 L capacity pots under two contrasting levels of irrigation (well-watered and water-deficit conditions). The results showed that the water productivity (WP) had a significant effect on plasticity values, with the Chilean accessions having the highest values. Furthermore, Illapel and Chepica genotypes presented the highest WP, MRD, and RV values under water-deficit conditions, in which MRD and RV were significant in the deeper layers (20–30 and 30–40 cm). Biplot analysis showed that the Illapel and Chepica genotypes presented a high WP, MRD, and RV, which confirmed that these may be promising drought-tolerant genotypes. Consequently, increased root diameter and volume in bottle gourd may constitute a response to a water deficit. The RSA traits studied here can be used as selection criteria in bottle gourd breeding programs under water-deficit conditions.

In the process of introducing cotton cultivars, it is essential to assess their productive behavior for different environments for which they will be recommended. Knowledge of the magnitude of the genotype interaction with environment allows the evaluation of the stability and adaptability of genotypes where one intends to introduce them, in addition to enabling the evaluation of the production potential and possible limitations of each environment. The study was conducted to determine the productivity, genotypic adaptability and genotypic stability of nine cotton cultivars (Gossypium hirsutum) in Mozambique, from 2004 to 2010 growing seasons. The genotypic stability and genotypic adaptability were assessed by Residual Maximum Likelihood (REML) and predict breeding values using Best Linear Unbiased Prediction (BLUP) methodology. The cultivars ISA 205, STAM 42 and REMU 40 showed superior productivity when they were selected by the Harmonic Mean of Genotypic Values (HMGV) criterion in relation to others. In turn, the cultivars CA 222, STAM 42 and ISA-205 were superior when selected by the Relative Performance of Genotypic Values (RPGV) and Harmonic Mean of the Relative Performance of Genotypic Values (HMRPGV). The cultivars CA 324 had the lower values for all criterions above. The cultivars CA 222 and STAM 42 will be the most recommended for farmers in cotton-growing regions and for the Cotton Breeding Program of Mozambique.