Leonardo Ferreira Dutra

Cutting time, indolebutyric acid and tryptophan in rooting of peach tree cuttings

The use of seeds to obtain rootstocks originates individuals different from the mother plant. Genetical homogenous material can be obtained by cutting. This work evaluates the effects harvest time of peach branches, tryptophan levels and the application of indolebutyric acid (IBA) on the rooting of cuttings kept in greenhouse under intermittent mist. Cuttings of Diamante, Capdeboscq and BR-2 cultivars were taken from branches half way in the growing season and prepared to be 12cm long, with two basical lateral incisions and one pair of apical leaves (except during winter). The cuttings were treated by immersion of the base for 5 seconds in indolebutyric acid solution at concentrations of 0, 1000, 2000, 3000 and 4000 mg L-1, and kept for 60 days in vermiculite-filled polyethylene bags under intermittent mist. Branches were collected and evaluated for endogenous tryptophan level and their correlation on cultivar rooting capacity. There were rooting differences among cultivars. Treatment with indolebutyric acid increased rooting percentual, number and dry matter weight of roots. The best results of rooting and number of roots per cutting were obtained in the spring and summer time; greater dry matter weight of the roots occurred during spring time. A negative correlation between endogenous tryptophan levels and rooting cuttings percentual was observed.The use of seeds to obtain rootstocks originates individuals different from the mother plant. Genetical homogenous material can be obtained by cutting. This work evaluates the effects harvest time of peach branches, tryptophan levels and the application of indolebutyric acid (IBA) on the rooting of cuttings kept in greenhouse under intermittent mist. Cuttings of Diamante, Capdeboscq and BR-2 cultivars were taken from branches half way in the growing season and prepared to be 12cm long, with two basical lateral incisions and one pair of apical leaves (except during winter). The cuttings were treated by immersion of the base for 5 seconds in indolebutyric acid solution at concentrations of 0, 1000, 2000, 3000 and 4000 mg L, and kept for 60 days in vermiculite-filled polyethylene bags under intermittent mist. Branches were collected and evaluated for endogenous tryptophan level and their correlation on cultivar rooting capacity. There were rooting differences among cultivars. Treatment with indolebutyric acid increased rooting percentual, number and dry matter weight of roots. The best results of rooting and number of roots per cutting were obtained in the spring and summer time; greater dry matter weight of the roots occurred during spring time. A negative correlation between endogenous tryptophan levels and rooting cuttings percentual was observed.

EFEITO DA APLICAÇÃO PRÉVIA DE ETHEPHON EM AMEIXEIRA (Prunus salicina Lindl) E DO IBA NO ENRAIZAMENTO DE SUAS ESTACAS

The work was carried out in a greenhouse with intermitent mist to verify the effect of ethephon (2-chloroetyl phosphonic acid) in plants, applied one week before of branch collection, and later treatment with indolebutyric acid (IBA) on rooting of cuttings of Frontier, Reubennel, Ace, Songold, Beauty and Roxa de Itaquera cultivars. The plants were sprayed with ethephon at 0 (zero); 50 and 100 mg.l-1 concentrations. Branches of the year from eight years old plants were collected and from them median cuttings departed with 15cm lenght and two leaves. Later, they were treated with IBA at 0 (zero) and 3000 mg.l-1 concentrations for 5 seconds immersion. The cuttings were packed in polietylene bags containing vermiculite with substrate. Ethephon increased the rooting percentage of Beauty cultivar and the IBA increased the rooting percentage of Roxa de Itaquera, Songold and Beauty cultivars. Different rooting potential among of plum cultivars was verified and the best ones were Frontier and Ace.

Efeito do substrato e da época de coleta dos ramos no enraizamento de estacas de ameixeira (Prunus salicina Lindl.)

This work was carried out in a greenhouse with intermittent mist out at the plant Science Department, Eliseu Maciel Agronomy College of Federal University of Pelotas (Brazil), aiming to evaluate the effect of different substratos and time of cutting on rooting of pium cuttings. Mild cuttings with 15cm length andapair of ieaves of Frontier cultivar were coilected from a commercial orchard eight years old in November 1993, January and March 1994. All cuttings were treated with indolbutiric acid (IBA) at 3000ppm concentration introducing about 1.0cm of their basal end in IBA powder and placed in tubes on isopor trays containing different substratos: washed mild sand: vermiculite of medium grains; rice husk ash and saw dust, utilized as isolated or as mixtures (1:1 v/v). Cuttings were kept on substratos for 60 days. The results demonstrated that the higher rooted cuttings percentage were obtained for cuttings collected in January and in March. The mixture of sand and saw dust gave the higher number of cuttings rooting with 68.22% and 65.99% for January and March.

BAP e substratos na aclimatização de plântulas de gloxínia (Sinningia speciosa Lood. Hiern.) provenientes de cultura de tecidos

The present work aimed to evaluate the influence of concentrations of 6-benzylaminopurine (BAP) used in acclimatization of gloxinia (Sinningia speciosa Lood. Hiern). Concentrations of BAP (0.0; 0.5; 1.0 and 2.0 mg L-1) in vitro and substrates (vermiculite, plantmax®, and vermiculite+plantmax®) were tested for acclimatization in every possible combination. After in vitro inoculation, the material was transferred to a growth chamber with temperature of 26±1oC and light intensity of 35 m mol m-2 s-1 for 16 hours, remaining under these conditions for 60 days. After that period, the plants obtained were transferred to pots containing substrates in a greenhouse. The evaluations were performed 120 days after cultivation. It were measured number of shoots, roots dry weight, above-ground dry weight, and number of flowers. On acclimatization, the best results for the variables were obtained with the use of the substrate Plantmax® or Plantmax®+vermiculite for plants originated from culture tissue.

Enraizamento in vitro do morangueiro (Fragaria x ananassa Duchesne) em diferentes concentrações do meio MS

The present work was carried out in the Tissue Culture Laboratory EMBRAPA/CPACT, Pelotas-RS, with the objective of verifying the behaviour in vitro of two cultivars of strawberry on different MS medium concentration. Strawberry explants, Hofla and Tangi cultivars coming from in vitro culture were tested on MS medium in the full, 3/4 and 1/2 strength suplemented with 30g/l sucrose, 100mg/l myo-inositol and 0.005mg/l benzylanimopurine (BA). Flasks (250ml) containing 40ml of medium culture with five explants per flasks were used. Cultures were maintained in a growth room at 25°C with a photoperiod of 16 h at 1.5 Klux for 32 days. Results indicated that the reduction in MS salts improved rooting explant by increasing the number of roots of the Tangi cultivar. A large root length was obtained with the Hofla cultivar in the 3/4 and 1/2 MS concentration. It was not observed any difference in the development of the plantlets among the cultivars due to the reduction in MS salts.

Influência do ácido indolbutírico e ethefon no enraizamento de estacas de pessegueiro (Prunus persica (L.) Batsch)

This work was conducted at the Plant Science Departament Eliseu Maciel Agronomy College of Federal University of Pelotas, in greenhouse with intermitent mist, aiming to evaluate the effect of indolebutyric acid and ethephon (2-chloroetyl phosphonic acid) on peach hranch cutting rooting. Median cuttings with 15cm length removed from Diamante cultivar branch were used. Two lateral lesions were made on cutting basis and they were treated with indolebutyric acid in liquid at 0; 1000; 2000; and 3000ppm concentrations and ethefon at 0; 50; 100 and 150ppm concentrations. The immersion time was five seconds and the cuttings were packed in polietylene sacks containing a mixture of sand and rice husk ash substrate (2:1 v/v). Results showed that the indolebutyric acid increased the rooted cuttings percentage up to 1752ppm concentration and the number of roots until 1791ppm concentration. The ethephon did not show significant variation for the form and concentrations used.