Matiello R.R.,State University of Ponta Grossa |
Lopes M.T.G.,Federal University of Amazonas |
Brunelli K.R.,Sakata Seed Sudamerica |
Camargo L.E.A.,University of Sao Paulo
Tropical Plant Pathology | Year: 2013
The objective of this study was to estimate the reduction in yield caused by Colletotrichum graminicola in resistant and susceptible maize hybrids inoculated at different stages of development. Two trials were conducted in different environmental conditions in a randomized block design with treatments arranged as a 2 × 5 factorial scheme and three replications. Treatments consisted of two hybrids (H8664, resistant and H8621, susceptible) inoculated at three growing stages (8-leaf, 12-leaf and tasseling stage). Internal lesion length, adjusted yield, and yield components (length, diameter and ear weight) were evaluated 120 days after emergence. Significant differences in yield and ear weight were detected in the susceptible hybrid inoculated at the earliest stage: yield was reduced by 16.1 and 20.2% in the first and second experiment, respectively. Although lesion length in the susceptible hybrid was approximately three times greater than in the resistant, there were no significant differences in lesion length among treatments for each hybrid. However, there were differences in the number of dead plants and ear weight. It is suggested that damage caused by early infection with C. graminicola results mainly from plant death and reduction in ear weigh rather than from the extent of colonization of the stalk. © Brazilian Phytopathological Society.
Diallel analysis and inbreeding depression of hybrid forage corn for agronomic traits and chemical quality [Análise dialélica e depressão endogâmica de híbridos forrageiros de milho para características agronômicas e de qualidade bromatológica]
de Souza Neto I.L.,Sakata Seed Sudamerica |
Pinto R.J.B.,State University of Maringá |
Scapim C.A.,State University of Maringa |
Jobim C.C.,State University of Maringa |
And 2 more authors.
Bragantia | Year: 2015
This study aimed to estimate the combining ability and inbreeding depression of corn hybrids for agronomic traits and forage quality. Nine corn hybrids, 36 F1 combinations from a diallel, 9 S1 populations and two checks were evaluated in two experiments in a randomized complete block design with three replications, in the 2009/2010 and 2010/2011 growing seasons. The parents Impacto, CD304 and DKB390 are recommended to form a composite to be subjected to a recurrent selection program aiming to improve forage production. Crosses between Impacto and parents DKB390, P30P34 and P30B39 are promising to increase forage quality by reducing the fiber content and also by increasing the protein content, being recommended for extracting inbred lines and interpopulation improvement. High inbreeding depression for grain yield was detected, indicating that non-additive effects contributed to the inheritance of the trait. © 2015 Instituto Agronomico. All rights reserved.
Pereira M.A.B.,Fundacao Centro Universitario UnirG |
De Azevedo S.M.,Sakata Seed Sudamerica |
De Freitas G.A.,Federal University of Tocantins |
Dos Santos G.R.,Federal University of Tocantins |
Do Nascimento I.R.,Federal University of Tocantins
Revista Ciencia Agronomica | Year: 2012
The objective of this work was to evaluate the adaptability and stability of 15 tomato genotypes in the area of Gurupi, Tocantins. The experiments were carried out in two environments [greenhouse: in the summer (December to March) and in open field: winter (June to September)], with 15 experimental tomato genotypes, being: four of the type long shelf life commercial ripening mutants and pre-commercial (rin): Tyler, Rebeca, Carmem and AF 13527; nine of the type long shelf life structural commercials and pre-commercial: Lumi, Débora Max, Michelli, Tammy, AF 12525, AF 11097, AF 13363, AF 13364 and AF 13525; and two of normal fruits: Santa Clara and Drica, in randomized block design with three repetitions. The long life genotypes e Tyler, Rebeca, AF 13364, AF 13525, AF 13527 it were classified as of stability and wide adaptability and wide adaptability for yield. For the average weight of commercial fruits, the genotypes Tyler, Michelli and AF 11097 presented wide adaptability to the evaluated environments.
Quartiero A.,UNICENTRO |
Faria M.V.,UNICENTRO |
Resende J.T.V.,UNICENTRO |
Figueiredo A.S.T.,UNICENTRO |
And 3 more authors.
Horticultura Brasileira | Year: 2014
The objective of this study was to evaluate the performance, heterosis and phenotypic stability of 50 genotypes of onion (a lineage and eight experimental hybrids of Baia group, 10 lineages and 22 experimental hybrids of Creole group, six open pollinated varieties and three commercial hybrids) in three crop seasons in Guarapuava, Paraná state, Brazil, in 2010/2011. Three experiments were carried out in randomized block design with three replications. Seedlings aging 45 days were transplanted on May 27, June 30 and August 03. We evaluated agronomic characteristics of bulbs. For the analysis of phenotypic stability of genotypes the method of Annicchiarico was used. We also estimated the heterosis of seven hybrids. The first period provided the highest values of average mass and increased yield of bulbs and the third period provided the lowest values. Only 26% of genotypes showed general confidence index (ωi) above 100% for bulb yield. The experimental hybrids HB1266, HB2285, HC3119, HC3126, HC3479 and HC3488 showed the highest confidence index for bulbs yield, although in the first period they did not participate in the group of highest yield genotypes. The mean of heterosis observed for the average mass of bulbs was 38%, ranging from 16% (HC3485) to 63% (hybrid HC3483) and for yield was 36%, ranging from 16% (HC3485) to 57% (HC3483).
Inheritance of resistance to papaya ringspot virus-watermelon strain (PRSC-W) in ‘whitaker’ summer squash line [Herança da resistência ao vírus da mancha anelar do mamoeiro estirpe melancia (PRSC-W) na linhagem de abobrinha ‘whitaker’]
Menezes C.B.,Embrapa Milho e Sorgo |
Maluf W.R.,Federal University of Lavras |
Faria M.V.,State University of the Central West |
Azevedo S.M.,Sakata Seed Sudamerica |
And 3 more authors.
Crop Breeding and Applied Biotechnology | Year: 2015
The objective of this work was to study the genetic control of the PRSV-W (Papaya Ringspot Virus - Watermelon Strain) resistance in Cucurbita pepo ‘Whitaker’ line. Plants of parental lines Whitaker (resistant) and Caserta (susceptible), and of the generations F1, F2, BC11 and BC12 were evaluated for their reactions to PRSV-W. Caserta plants showed severe mosaic symptoms, while Whitaker grew vigorously and remained almost totally symptom-free. Most of the F1, F2 and backcross plants also presented severe mosaic symptoms. Data were used to test a hypothesis of monogenic inheritance under different presumed degrees of dominance, and genetic models were tested using maximum likelihood tests of genetic control. Broad-sense heritability was of 0.57 for the first evaluation. Resistance to PRSV-W in C. pepo ‘Whitaker’ is due to a major gene effect summed to polygenic effects. © 2015 Brazilian Society of Plant Breeding. All rights reserved.
Tavares A.E.B.,São Paulo State University |
Claudio M.T.R.,Sakata Seed Sudamerica |
Nakada-Freitas P.G.,São Paulo State University |
Cardoso A.I.I.,São Paulo State University
Horticultura Brasileira | Year: 2016
The optimization of space in vegetable production is very important to the farmer; sometimes this is the threshold of profit. New arrangements of plants with different provisions seek to maximize production. The objective of this research was to evaluate the productivity of edible pea pods in different planting densities, varying the spacing between holes and the number of plants per hole. The experimental design was randomized blocks, with eight treatments in a factorial scheme 4 × 2 (spacing among holes of 0.2, 0.3, 0.4 and 0.5 m with 1 or 2 plants per hole), representing densities of 20,000 to 100,000 plants/ha for spacing of 1.0 m between rows, with six replications. We evaluated the total production/ha, the marketable production/ha and per plant, and the number of marketable pods/ha and per plant. The data were submitted to the F test, and the means concerning number of plants per hole were compared by Tukey’s test and the spacing between holes by regression analysis. Higher productivity was obtained (15.53 t/ha with 2 plants per hole) and lower production of pods per plant (150 g, with 2 plants per hole), the smaller the spacing (0.2 m). However, if the farmer decides to plant on greater spacing, the density of two plants per hole is recommended. © 2016, Sociedade de Olericultura do Brasil. All rights reserved.
Faria M.V.,UNICENTRO CEDETEG |
Morales R.G.F.,UNICENTRO CEDETEG |
de Resende J.T.V.,UNICENTRO CEDETEG |
Zanin D.S.,UNICENTRO CEDETEG |
And 2 more authors.
Horticultura Brasileira | Year: 2012
The use of onion hybrids in Brazil is still recent, with little information regarding the gains from heterosis. However, the first step to exploit the heterosis is the evaluation of available germplasm. Due to the need for genotypes adapted to the climatic conditions of South-Central region of Paraná state, Brazil, this study aimed to evaluate the agronomic performance of 19 hybrids and 50 inbred lines of onion, as well as the heterotic gain of six of these hybrids. The experimental design was randomized blocks with three replications. The evaluated traits were yield, average weight of the bulbs, commercial classification of bulbs, waxy of the leaves and cycle. In general the hybrids were superior to the lineages in yield and average bulb weight and had lower cycle. The heterotic gain in hybrids was evident, indicating the viability of hybrids for cultivation in the region. Hybrids 2572, 2573 and 2578 are promising due their high yield, earliness cycle and better classification of the bulbs. The lineages 2507-1 and 2983 provided the highest heterotic gain for the yield of the hybrid 2857, which was classified in the group of earliest genotypes, showing an inverse correlation between these two characters.
Moura M.F.,São Paulo State University |
Mituti T.,São Paulo State University |
Marubayashi J.M.,São Paulo State University |
Gioria R.,Sakata Seed Sudamerica |
And 4 more authors.
European Journal of Plant Pathology | Year: 2011
Pepper yellow mosaic virus (PepYMV) is the most important potyvirus infecting sweet pepper in Brazil. In this study, twenty isolates of PepYMV were obtained from commercial sweet pepper crops. To confirm virus identity, the coat protein gene was completely sequenced for eleven of these isolates, and partially sequenced for the other nine isolates. The amino acid identities obtained were above 93% when compared with the sequence of a characterized PepYMV isolate (AF348610). Extracts of Nicotiana tabacum cv. TNN plants infected with the different isolates were used to inoculate the differential series of Capsicum spp cultivars containing the genes pvr2 1, pvr2 2, pvr2 3, pvr2 4, and Pvr4. Using the same criteria established for Potato virus Y (PVY), fourteen isolates of PepYMV could be classified as known pathotypes described for PVY, that is: 1.2 (2 isolates), 1.3 (6) and 1.2.3 (6). The remaining six isolates, 1.3 (2) and 1.2.3 (4) could not be classified into the typical pathotypes of PVY because they were also virulent on Serrano Criollo de Morellos-334 (C. M 334) which carries the pvr2 3 and Pvr4 genes. To classify the PepYMV into pathotypes and counter the biological diversity found in this species we propose the utilization of 2 x for the ability to overcome the correspondent allele of the pvr2 locus and 4 for the capacity to break down the Pvr4 gene. Using this criterion we could classify the PepYMV into five pathotypes: 2 1.2 2; 2 1.2 3; 2 1.2 2.2 3; 2 1.2 3.4 and 2 1.2 2.2 3.4. © 2011 KNPV.
Estimates of the combining abilities for pink root resistance and agronomic traits in onions [Estimativas de capacidades de combinação em cebola para resistência a raíz rosada e caracteres agronômicos]
Lima dos Santos R.,São Paulo State University |
Pavan M.A.,São Paulo State University |
da Silva N.,São Paulo State University |
Gioria R.,Sakata Seed Sudamerica |
Leite de Souza Neto I.,Sakata Seed Sudamerica
Summa Phytopathologica | Year: 2015
Aimed at estimating the combining abilities for pink root resistance and agronomic traits in onion (Allium cepa L.), the present study was carried out by using partial diallel scheme. Two partially endogamic inbred line groups were used as parents. Group I consisted of five male-sterile female inbred lines, originated from a Brazilian Tropical Onion Population, selected for sowing during the summer. Group II consisted of ten male inbred lines, most of which originated from Crioula onion populations, obtained by successive selfpollination and kept by mass selection within lines. The following traits were evaluated: pink root resistance using a score scale from 1 to 5, leaf vigor, leaf architecture, number of leaves, plant height (cm), total number of bulbs and total weight of bulbs (kg). Experimental design was in randomized blocks with three replicates. There were additive effects on pink root resistance and considerable non-additive effects for some combinations; the same genetic behavior was found for the other agronomic traits of interest. Thus, intrapopulation selection can be done with the inbred lines used in the current study and hybrids of high level of pink root resistance, as well as good agronomic traits, can be obtained. © 2015, Universidade Estadual Paulista (UNESP). All rights reserved.
Rocha K.C.,São Paulo State University |
Sakate R.K.,São Paulo State University |
Pavan M.A.,São Paulo State University |
Kobori R.F.,Sakata Seed Sudamerica |
And 2 more authors.
Summa Phytopathologica | Year: 2012
Tomato severe rugose virus (ToSRV) is the predominant species of begomovirus affecting pepper crops in São Paulo State, Brazil. Its occurrence is relatively recent for the culture thus, there is no information on yield losses caused by this virus on sweet pepper. The aims of this study were to evaluate yield and fruit fquality of three pepper cultivars (Magda, Amanda and Rubia R) infected with ToSRV. There was marked reduction in the number of fruits and in the growth of plants; however, ToSRV did not significantly influence the average weight, diameter and the length of fruits. The results obtained so far lead to the conclusion that ToSRV causes damage in peppers and it is necessary the development of resistant cultivars to ToSRV.