Elio Kersten

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.

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.

Influência do ethephon e do ácido indolbutírico no enraizamento de estacas de ramos de goiabeira (Psidium guajava L.)

The objective of this work was to evaluate the influence of ethephon, indole butyric acid (IBA) and substrate on root formation of guava stem cuttings. Orchard plants withfive years old were sprayed with ethephon in concentrations of zero, 50 and 100ppm. However, after seven days, stem cuttings were made, of the last lauching with three knots by cutting including one pair of leaves. Cuttings were treated with concentrations of zero, 1000, 2000. 3000 and 4000ppm of liquid IBA by immersion of two centimeter of the basis of cutting for five minutes. Vermiculite and ash rice were used as substrato. Results showed that the use of vermiculite produced greater percentage of cuttings rooted (21.48%). A greater cutting rooted and number of roots were obtained using ethephon and IBA.

Enraizamento de ameixeira (Prunus salicina, Lindl.) em diferentes épocas de coleta das estacas

The objective of the present work was to verify the best time for cropping stem cuttings of plum for rooting. The experiment was conducted in Pelotas, RS with two cultivars: Reubennel and Frontier. The stem cuttings were taken from the season growth of six years old stem base in three different times: November of 1992, January and March of 1993. Cuttings from the other times were rooting in plastic tubets using rice hulls ash as substrato and kept under intermitent misting. The results showed no cropping time influence in the percentual rooting of Reubennel cultivar, which was low in each determination. However, the cultivar Frontier presented a greater percentual of rooting in November (94.9%), followed in March (34.8%) and in January (25,8%).

Germinação e vigor de sementes de goiaba (Psidium guajava L.) submetidas a métodos para superação da dormência

This work was conducted to study the germination test and the germination speed rate of guava seeds (Psidium guajava L.). Guava seeds were coilected from ripe fruits of a commercial orchard in Pelotas, RS. The experiment was carried out at the Seed Analysis Laboratory/ Plant Science Department - FAEM/UFPel. The seed treatments used were: a) refrigerated stratification around 5°C during 0, 10, 20, and 30 days; b) concentrated sulfuric acid scarification through 15 minutes immersion and medium washed sand seeds attrition during 15 minutes. The experimental design was a completely randomized with 4 replications of 50 seeds. After each seed treatment, seeds were placed in the paper and sand substratos: germinator chamber at constant 25°C and at room temperature. The germination occurred between 8 and 11 days in the germinator chamber. The substrate showed significativo effect only for germination and sand showed higher germination average values. Sands was the best scarification treatment for both situations. The stratification treatment decreased the germination and increased the germination speed rate of guava seeds.