Diallel analysis in cotton (Gossypium hirsutum L.) for water stress tolerance

Information about combining ability is important in determining breed- ing strategies. The objective of this study was to estimate the general (GCA) and specific (SCA) combining abilities among twenty cotton hybrid combinations submitted to water stress, based on agronomic traits. The trails were carried out in semiarid environment (Barbalha, CE), during two years, in dry season under irrigation, and submitted to 23 days of water suppression. Wide variability was verified among parents and their hybrids, with additive effects to seed yield, lint percentage, blooming and boll weight. Dominance effect was found only to plant height. The combinations BRS 286 x CNPA 5M, BRS RUBI x CNPA 5M, FM 966 x CNPA 5M and BRS 286 x BRS Seridó showed the best SCAs and aver- ages for the majority of the traits. In addition, at least one of their parents had high CGA. These combinations must be advanced in cotton breeding program

Genetic parameters and path analysis of traits of upland cotton for the brazilian semi-arid region

Upland cotton fiber is one of the most used natural fibers in the production of textile materials worldwide. For this reason, the selection of genotypes that meet the industry’s requirements is one of the main goals of cotton breeding programs. This study aimed to estimate the phenotypic and genotypic correlations among fiber traits and identify the direct and indirect effects of these traits on seed cotton yield of upland cotton genotypes in the semi-arid Brazilian Northeast. This study assessed 21 upland cotton genotypes from a complete diallel cross without reciprocals. The design was randomized blocks, with three replications and 21 treatments. The experiment was conducted in the municipality of Patos - PB, in 2015. The statistical analysis consisted of analysis of variance by the F test, phenotypic and genotypic correlation analysis, and path analysis. The studied materials revealed genetic variability for all traits. Path analysis has shown that the traits fiber elongation, fiber strength, and fiber fineness have a direct positive effect on seed cotton yield

Seleção de clones de cajueiro-anão para o plantio comercial no Estado do Ceará

The main problem to Brazilian cashew growers is the orchard low productivity, presently below 220 kg ha-1 year-1 of nuts. For this reason, obtaining new selections is the main research goal. In this paper, the results of the evaluation of thirty rain-fed dwarf cashew clones (including four controls) carried out from April/1990 to February/1997 at the Estação Experimental, at Pacajus, CE, Brazil, are presented. The experimental design was in randomized blocks with four replications and four plants per plot, spaced 7 m x 7 m. The results revealed that the clones CAP 01, CAP 05 and CAP 12 with 70% average higher than the controls (2.4 m) have a medium canopy size between the common type and the dwarf type. The canopy diameter of the clones CAP 10, CAP 06 and CAP 26 was 63% higher than the controls (4.8 m) and the clones CAP 02, CAP 07, CAP 24 and CAP 25 showed the lowest values for this trait. Nut yield of the clones CAP 12, CAP 18 and CAP 26 was, respectively, 1,510; 1,281 and 1,262 kg ha-1 at the fifth year, that is, 175% higher than that of the best control, and the clones CAP 12 and CAP 18 were the most regular among all clones during the evaluation period. The kernel weight ranged from 1.9 to 3.2 g and 16 clones presented kernel weighting more than 2.5 g which are the most valuable in the international market. Four clones presented kernel percentage (29.4% to 30.6%) higher than the best control (28.1%) which means 38% over the industrial average (22%), and the clones CAP 11, CAP 06, and CAP 05 had less than 2% of broken kernel. The results pointed out the CAP 06 and CAP 26 clones as the most promising ones.O principal problema da cajucultura no Brasil é a baixa produtividade dos pomares, atualmente menos de 220 kg ha-1, de castanha, razão pela qual a prioridade é a obtenção de novas cultivares. Neste trabalho são apresentados os resultados da avaliação de 30 clones de cajueiro (incluindo quatro testemunhas), em regime de sequeiro, efetuada entre abril de 1990 e fevereiro de 1997, na Estação Experimental de Pacajus, CE, Brasil. O delineamento experimental foi o de blocos ao acaso, com quatro repetições e quatro plantas/parcela, com espaços de 7 x 7 m. Os resultados mostraram que os clones CAP 01, CAP 05 e CAP 12, com altura mais de 70% superior aos 2,4 m médios das testemunhas, são de porte intermediário entre os tipos comum e anão-precoce. O diâmetro da copa dos clones CAP 10, CAP 06 e CAP 26 foi superior em mais de 63% aos 4,8 m médios das testemunhas; os clones CAP 02, CAP 07, CAP 24 e CAP 25 foram os de menor envergadura. A produção dos clones CAP 12, CAP 18 e CAP 26 foi, respectivamente, de 1.510, 1.281 e 1.262 kg ha-1 de castanhas, no quinto ano, ou seja, 175% maior do que a testemunha mais produtiva, e o CAP 12 e o CAP 18 foram os mais regulares quanto a este caráter. O peso da amêndoa variou de 1,9 a 3,2 g, com 16 clones apresentando amêndoas superiores a 2,5 g (as de maior preço no mercado internacional de nozes). Quatro clones apresentaram rendimento de amêndoa acima dos 28% da melhor testemunha (são obtidos 22% na indústria brasileira), e os clones CAP 11, CAP 06 e CAP 05 apresentaram menos de 2% de amêndoas quebradas. Os resultados apontaram os clones CAP 26 e CAP 06 como os mais promissores

Fibra de cultivares de algodoeiro sob condições de sequeiro

Objetivando avalizar as características de fibra do diferentes cultivares de algodão realizou-se uma pesquisa Campo Experimental da Fazenda Escola da Faculdade de Tecnologia do Instituto Centro de Ensino Tecnológico, Sertão Central, no município de Quixeramobim, Ceará, cujas coordenadas geográficas Latitude (S) 05°11'57’’S, Longitude (W) 39°17'34’’W e Altitude (M) 191. O regime de chuvas local varia de 700 a 750mm. Estas chuvas se concentram no período de janeiro a junho. A época do plantio de Quixeramobim, foi em fevereiro caracterizando como safra normal. O delineamento experimental utilizado para o ensaio foi o de blocos ao acaso com quatro repetições e vinte tratamentos, sendo que a parcela experimental foi constituída por quatro linhas de 5 metros linear, com espaçamento entre linhas de 0,90 metros, estande entre 6 a 9 plantas/m. A área útil da parcela utilizada para obtenção dos dados, foram as duas linhas centrais, nesse ensaio utilizou-se as linhagens e ou cultivares referente ao ano/safra 2019. Concluiu-se que há variabilidade fenotípica os tratamentos apresentaram diferenças significativas para a maioria dos caracteres e as cultivares BRS 416, BRS 286 e BRS 293 são as de melhores desempenhos pois associaram as melhores médias para produtividade de pluma e para as características de fibras