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"July 2002" Bibliography: leaves 40-46.

Chiloglanis pretoriae is a rock catlet, indigenous to southern Africa. The aim of the study was to develop a technique to culture C. pretoriae as an alternative to harvesting and selling wild caught fish on the international aquarium trade. As nothing was known about the culture of African rock catlets an investigation into the biology and ecology of the species was necessary to develop the culture protocol. Chiloglanis pretoriae inhabits fast flowing rapids (current speeds over 0.6 metres per second). It is a serial interstitial gravel spawner, that spawns during the summer months. Chiloglanis pretoriae is a carnivorous fish species, feeding on aquatic insects. The natural growth rate is relatively fast in the first two years where after it levels off. Sexual maturity (50%) is attained within the first year (44mm total length). From the four cell stage, embryos took seven days to hatch, 16 days to first feeding and 75 days to reach the juvenile phase. The free embryos were well developed and readily accepted artificial feed at first feeding. The fish spawned readily, without hormone induction, in a continuous raceway. Spawning in the 801 retangular glass aquaria was irregular. The substrate within the raceway consisted of gravel and large rocks. The current was maintained at 0.6m/sec, temperature at 26± 0.6⁰C, dissolved oxygen concentrations at 7.1± 0.3mg/l, pH at 6.9± 0.2 and photoperiod at 16L:8D. Conductivity was monitored and remained within the acceptable range of C. pretoriae (84± 10uS/m).

This study examined the effect of density on rhizome bud production in quackgrass (Elytrigia repens (L.) Nevski). The treatments consisted of two biotypes (L8 and L9), and nine density levels ranging from 1 to 22 plants m$ sp{-2}$. The results showed that bud production per plant diminished with increasing density in both biotypes. However, biotype L8 was less productive at low densities, but almost equal to L9 at higher densities. A second experiment was undertaken to measure the expansion of clonal colonies and the distribution of shoots within these colonies. For both biotypes the growth rate was highest in late summer and early fall, but colonies of L9 grew more rapidly. Biotype L9 had 59% of its total biomass located within 40 cm of the centre as compared with 81% in L8. Overall, Biotype L9 produced more rhizome buds, responded more strongly to intraspecific interference, and grew more rapidly as a colony.

A two year study was conducted to investigate the effect of intercropping corn with alfalfa or red clover with or without an initial application of the herbicide EPTC$ sp+$ (S-ethyl dipropylthiocarbamate + R-25788 antidote) on the weed yellow nutsedge (Cyperus esculentus L.). EPTC$ sp+$ applied prior to crop seeding in 1984 significantly reduced yellow nutsedge shoot growth in the first year but did not significantly reduce tuber populations. EPTC$ sp+$ significantly improved corn silage and grain yield and alfalfa establishment in the first year but did not significantly improve red clover establishment. In the second year, a trend of superior forage legume establishment and lower yellow nutsedge shoot production was observed in those treatments established the previous year with EPTC$ sp+$. Over the two year period, yellow nutsedge tuber populations in treatments established with EPTC$ sp+$ were significantly greater in the monocropped corn treatment than in any other treatment. In treatments established without a herbicide, yellow nutsedge tuber populations were also greatest in the monocropped corn treatment.

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-06-06T17:54:47Z No. of bitstreams: 1 2016 - Tomaz Ribeiro Lanza.pdf: 4430887 bytes, checksum: 399457041f3b433d4633da73992ed2e6 (MD5) / Made available in DSpace on 2017-06-06T17:54:47Z (GMT). No. of bitstreams: 1 2016 - Tomaz Ribeiro Lanza.pdf: 4430887 bytes, checksum: 399457041f3b433d4633da73992ed2e6 (MD5) Previous issue date: 2016-02-01 / FAPERJ / This study aimed to evaluate work in this plant densities on banana cultivation under phytotechnical aspects as well as the dynamics of weeds. The experiment was conducted in the experimental field of Horticulture - Plant Industry of UFRRJ, Serop?dica/RJ municipality in the agricultural year 2014/2015. micro propagated seedlings of banana type were used apple "BRS Princess" in a total of six treatments: 1200 (3.33 x 2.5 m), 1600 (2.5 x 2.5 m), 2000 (2.0 x 2.5 m), 2400 (1.67 x 2.5 m), 2800 (1.43 x 2.5 meters) and 3200 (1.25 x 2.5 m) plants per hectare arranged in experimental design a randomized block design with four replications. The experimental plot consisted of three rows with four banana plants in each, three plants of the center line, considered as useful plants. It evaluated monthly on the first and second production cycle, phytotechnical indicators of banana trees growing through the measurement of plant height, pseudostem diameter, leaf emergence and active leaves. For production parameters were measured quantitative aspects as bunch weight and fruit, stems parameters and standardization of fruit. Data were subjected to analysis of variance by F test and when significant models were adjusted for the biological phenomenon, the regression coefficient and the significance of the parameters. The phytosociological study of weed was made by sampling in installments, one one month after transplanting, and the following every 90 days, totaling six samples in 16 months of cultivation. They used square hollow 0.3 m side launched at random three times within each plot. The plants contained in the square were collected, identified and separated by species, counted and placed in an oven at 60 ? C for determination of dry matter. With the data obtained, the phytosociological indices were calculated: Relative density (De.R) Relative frequency (Fr.R) on Dominance (Do.R), importance value (IVI), the weed community. It was found that in the first cycle banana trees showed homogeneous development of the six treatments, except for diameter, with higher values for lower density treatments. For plants of the second cycle was observed significant influence of planting densities for vegetative parameters, with the exception of active leaves. As regards the production aspects, it was observed that the densities influence on the quantitative aspects of fruits such as grapes and fruit weight, but did not influence the standardization of fruit. Based on the phytosociology of weed it was possible to see significant changes in the dynamics of species, particularly as regards the reduction of species of the family of Poaceae, particularly P. maximum, and increased diversity and IVI more tolerant species to shading. As for the cultural control of banana trees on the weeds, it was observed that there was a lower density and dominance of weeds with the densification of culture. Based on the research results it can be concluded that the tested population densities did not affect vegetative aspects of growth of bananas the first cycle, but with significant effect on the second production cycle plants. It is noted that the planting densities influenced productive aspects of banana trees, and also favored higher productivities with plant density. It is also possible to conclude that the different banana planting densities influence the population dynamics of weeds as well as the cultural control of these. / Objetivou-se no presente trabalho avaliar densidades de plantas na cultura da banana sob aspectos fitot?cnicos bem como na din?mica de plantas daninhas. O experimento foi conduzido no campo experimental de Horticultura ? Setor de Fitotecnia da UFRRJ, munic?pio de Serop?dica/RJ no ano agr?cola de 2014/2015. Foram utilizadas mudas micro propagadas de banana tipo Ma?? ?BRS Princesa?, em um total de seis tratamentos: 1200 (3,33 x 2,5 m), 1600 (2,5 x 2,5 m), 2000 (2,0 x 2,5 m), 2400 (1,67 x 2,5 m), 2800 (1,43 x 2,5 m) e 3200 (1,25 x 2,5 m) plantas por hectare, dispostos em delineamento experimental de blocos ao acaso, com quatro repeti??es. A parcela experimental foi composta de tr?s linhas contendo quatro plantas de banana em cada, sendo tr?s plantas da linha central, consideradas como plantas ?teis. Avaliou-se, mensalmente, no primeiro e segundo ciclo de produ??o, indicadores fitot?cnicos de crescimento das bananeiras, atrav?s da mensura??o da altura da planta, di?metro do pseudocaule, emiss?o de folhas e folhas ativas. Para par?metros de produ??o foram mensurados aspectos quantitativos como peso do cacho e dos frutos, par?metros do enga?o e padroniza??o de frutos. Os dados foram submetidos a an?lise de vari?ncia pelo Teste F e quando significativos os modelos foram ajustados em fun??o do fen?meno biol?gico, do coeficiente de regress?o e da signific?ncia dos par?metros. O estudo fitossociol?gico de plantas daninhas foi realizado atrav?s de amostragens nas parcelas, sendo uma ap?s um m?s do transplantio, e as seguintes a cada 90 dias, totalizando seis amostragens em 16 meses de cultivo. Utilizaram-se quadrados vazados de 0,3 m de lado lan?ados ao acaso tr?s vezes dentro de cada parcela. As plantas contidas no quadrado foram coletadas, identificadas e separadas por esp?cie, contabilizadas e colocadas em estufa a 60?C para determina??o da massa da mat?ria seca. Com os dados obtidos, foram calculados os ?ndices fitossociol?gicos: Densidade relativa (De.R), Frequ?ncia relativa (Fr.R), Domin?ncia relativa (Do.R), ?ndice do valor de import?ncia (IVI), da comunidade de plantas daninhas. Verificou-se que no primeiro ciclo as bananeiras apresentaram desenvolvimento homog?neo nos seis tratamentos, exceto para di?metro, com valores superiores para os tratamentos de menor densidade. Para as plantas do segundo ciclo observou-se influencia significativa das densidades de plantio para os par?metros vegetativos, com exce??o de folhas ativas. Quanto aos aspectos de produ??o, observou-se que as densidades de plantio influenciaram nos aspectos quantitativos dos frutos, como peso do cacho e dos frutos, por?m n?o influenciaram na padroniza??o dos frutos. Com base na fitossociologia das plantas daninhas foi poss?vel verificar altera??es significativas na din?mica de esp?cies, principalmente no que se refere a redu??o de esp?cies da fam?lia das Poaceae, com destaque para P. maximum, e aumento da diversidade e do IVI de esp?cies mais tolerantes ao sombreamento. Quanto ao controle cultural das bananeiras sobre as plantas daninhas, foi poss?vel observar que houve menor densidade e domin?ncia de plantas daninhas com o adensamento da cultura. Com base nos resultados da pesquisa ? poss?vel concluir que as densidades populacionais testadas n?o afetaram aspectos vegetativos de crescimento das bananas do primeiro ciclo, por?m com efeito significativo nas plantas do segundo ciclo de produ??o. Observa-se que as densidades de plantio influenciaram aspectos produtivos das bananeiras, e tamb?m favoreceram maiores produtividades com o adensamento de plantas. Tamb?m ? poss?vel concluir que as diferentes densidades de plantio de banana interferem na din?mica populacional de plantas daninhas assim como no controle cultural dessas.

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