Pruning levels for Zante currant

Fourteen-year-old Zante currant vines of average vigor were pruned to 60, 90, 120 or 150 buds in a two-year trial to estimate the optimum number of buds as a pruning level.The results suggest that 90 to 120 buds is the optimum number for pruning of Zante currant. This could be used without affecting the quality of the shoots produced for pruning in the following year. Result

Effects of GA and CCC on setting, splitting, yield and quality of Zante currant (Vitis vinifera var.)

Ten-year-old Zante currant vines (Vitis vinifera var.) were sprayed in two seasons with GA at 1 ppm+ CCC at 100 ppm or GA at 1 ppm+ PCPA at 20 ppm as soon as capfall was complete. The average number of flowers per bunch for a random selection of primary bunches was 568 in 1967 and 574 in 1968. Natural setting without treatment on these bunches was 66 per cent in 1967 and 44 per cent in 1968.Berry deve1opment is the main problem in the production of Zante currant. Susceptibility to splitting was associated in this trial with amount of rain that fell during the 3 weeks prior to harvest and with berry size. Ten mm of rain caused 52 per cent splitting on untreated vines in one season while 2 mm of rain caused 9 per cent splitting in the other. Treatments with GA+ CCC or GA+ PCPA, although both improving berry setting, differ in their effects on the final quality and dried yield of these berries. GA+ CCC produced acceptably sized berries with high sugar content, and of advanced maturity and colour, with less tendency to split, and high dried yield, while GA+ PCPA produced excessively large sized berries with low sugar content and retarded maturity and colour, which split more readily, resulting in 22 per cent dried yield reduction over two years

Effect of topping, pinching, cincturing, and PCPA on the yield of Zante currant (Vitis vinifera var.)

A factorial trial was carried out by using forty-year-old Zante currant vines (Vitis vinifera var. Zante currant; Black Corinth), to compare the effect of some cultural practices on fresh and dried fruit yield, berry size and sugar content. It showed that cincturing over the two years of the trial increased the fresh and dried fruit yield. PCPA sprays failed to increase yield and produced excessibely large berries, while topping and pinching have no significant effect on yield

Effects of some growth regulators on the fresh and dry yield of Zante currant (Vitis vinifera var.)

The results of two trials with Zante currant vines (Vitis vinifera var. Zante currant, Black Corinth) are reported. Trial I was for two seasons on ten-year-old vines which had never been cinctured (girdled) but until this trial had been sprayed with GA Y. ppm+ PCPA 20 ppm at full bloom. Trial II was for one season only on forty-year-old vines which had been cinctured up to 1960, then sprayed with GA Ye ppm+ PCPA 20 ppm at full bloom until this trial. In the first trial GA at 1 ppm + CCC at 100 ppm applied at full bloom increased the yield of dried fruit over two seasons by 37 per cent and 32 per cent compared with GA at 1 ppm+ PCPA at 20 ppm and GA at 1 ppm respectively, while maintaining acceptable berry size and sugar content. The second trial suggests that this increase in yield is largely due to an increase in the number of berries per bunch with GA+ CCC at the concentrations used here. There was little difference between overall sprays and bunch-directed sprays

Effects of time of application of GA + CCC on yield and splitting of Zante currant Vitis vinifera var.

To find out the effect of the concentration and of the time of application of GA + CCC on yield and splitting of Zante currant, two trials were conducted over three seasons, 1968-69 to 1970-71.In the first trial, in applications up to the time of full bloom (defined as the stage of flowering 1 day after an estimated 90-95 per cent of the calyptras had fallen) GA 0.5 ppm + CCC 50 ppm was as good as twice the concentration except for berries per bunch (earliest application) and sugar content (latest application). The second trial showed over two seasons that GA 1 ppm + CCC 100 ppm gave the highest yields of dried fruit if applied between full bloom and ten days later. This timing is the same as for cincturing. Splitting was found to be associated with the amount of rain that fell during the three weeks from January 11 to February 1 and with the nature and timing of the berry setting and sizing spray. In the rainy pre-harvest season of 1970-71 when splitting of currants was very bad, least splitting occurred with GA 1 + CCC 100 at full bloom or four days after - 42 to 46 per cent, compared with 76 per cent with GA+ PCPA.Der Einfluß des Anwendungszeitpunktes von GS + CCC auf den Ertrag und dasPlatzen der Beeren bei Vitis vinifera „Zante currant"Während dreier Vegetationsperioden, 1968/69 bis 1970/71, wurden zwei Versuche über den Einfluß von Konzentration und Anwendungszeitpunkt der Kombination Gibberellinsäure (GS) und CCC auf den Ertrag und das Platzen der Beeren bei Zante currant durchgeführt. Im ersten Versuch hatte die Anwendung von 0,5 ppm GS + 50 ppm CCC, spätestens während der vollen Blüte - definiert als die Blühphase 1 Tag nach dem Abwerfen von etwa 90-95%der Calyptren - dieselbe Wirkung wie Verdoppelung der Konzentration, abgesehen von der Anzahl Beeren je Traube (früheste Behandlung) und dem Zuckergehalt (letzte Applikation). Der zweite Versuch erbrachte in zwei Vegetationsperioden die höchste Rosinenausbeute, wenn 1 ppm GS + 100 ppm CCC zwischen vollem Erblühen und 10 Tage danach angewandt wurden. In dieser Zeit wird auch die Ringelung vorgenommen.Das Aufplatzen der Beeren war mit der Niederschlagsmenge gekoppelt, die während der drei Wochen vom 11. Januar bis 1. Februar fiel, sowie von Art und Zeitpunkt der Beerenansatz und -größe fördernden Spritzungen abhängig. In der Regenperiode vor der Ernte 1971, während der ein erheblicher Teil der Beeren aufplatzte, wurde bei den mit 1 ppm GS + 100 ppm CCC zur Zeit der vollen Blüte oder 4 Tage danach behandelten Reben der geringste Anteil geplatzter Beeren beobachtet, nämlich 42-46% gegenüber 76% bei den mit GS + PCPA behandelten Reben

Gibberellic acid, chlorocholine chloride and yield increases in Zante currant

GA and CCC additively increased yield of Zante currant fruit. GA induced an increase in berry size (weight and volume) which was unaffected by CCC, while CCC offset to an appreciable extent the reduction in berry number associated with low concentrations of GA

Efeitos de retardadores de crescimento na frutificação da videira 'Niagara Rosada'

Studies were carried out to establish the effects of exogenous growth regulators on Vitis (labrusca x vinifera) 'Niagara Rosada' fruiting. The investigations were done in the Jundiaí Research Station, Agronomic Institute State of São Paulo, always using disease-free vineyards of good productivity. The morphological transformations of clusters were studied under the following aspects: weight, length and width of cluster; weight, length average and width average of berries: length average/width average ratio of berries; length and diameter of rachis; width of cluster minus berries; length and diameter of secondary rachis. The yield for the first half of the period from flowering to maturation was first determined. The same characteristics were determined at the time of maturity plus the number of berries, number of seeds, total sugars, total acid, Maturity Index and reducing sugars in samples of all treatments. The experiment was conducted in order to determine the doses that resulted in the most beneficial effects, always using applications by immersion of the inflorescence. In the experiment was realized applications of (2-chloroethyl) trimethylammonium chloride (CCC) and succinic aeid-2, 2-dimethylhydrazide (SADH) at concentrations of 50, 100, 250, 500, 1000 and 2000 ppm; CCC 500 ppm plus SADH 500 ppm and nontreated, 5 days before flowering, in 1971. The concentrations of CCC applied before flowering did not affect favorably cluster morphology under the conditions of the experiment. Application of SADH at 250 ppm before flowering increased the cluster weight and length, berries number and weight, and seed number. In the first yield treatment of 1000 ppm of SADH increased the cluster weight and lenght, berry weight and rachis lenght.Estudou-se a influência da aplicação por imersão, de retardadores de crescimento (CCC e SADH), 5 dias antes do florescimento, nas características morfológicas da panícuia da videira Vitis (labrusca x vinifera) 'Niagara Rosada'. Neste ensaio verificou-se que as concentrações de CCC aplicadas em pré-florescimento, não afetaram favoravelmente a morfologia das panículas da cultivar estudada, nas condições do ensaio. SADH na dosagem de 1000 ppm provocou, na primeira colheita, aumento no peso e comprimento da panícula, no peso das bagas, e no comprimento da ráquis, proporcionando a formação desejada de uma panícula mais alongada, nas condições estudadas. Aplicação de SADH na concentração de 250 ppm em pré-florescimento, promoveu aumento no peso e comprimento da panícula, número e peso das bagas, além do inconveniente de elevar o número de sementes

Application of plant growth regulators at pre-harvest for fruit development of 'PÊRA' oranges

The aim of the present work was to evaluate the effects of auxins and gibberellins when applied at pre-harvest to the fruit development, and to the ripening and natural fall of the fruit, in 'Pêra' oranges. Trees of Citrus sinensis Osbeck cv. Pêra, 5 years old, were utilized. The treatments applied were: GA3 + 2,4-D 12.5mg L-1 of each; GA3 + 2,4-D 25mg L-1 ; GA3 + 2,4-D 37.5mg L-1; GA3 + NAA 12.5mg L-1; GA3 + NAA 25mg L-1; GA3 + NAA 37.5mg L-1; NAA + 2,4-D 12.5mg L-1; NAA + 2,4-D 25mg L-1; NAA + 2,4-D 37.5mg L-1; and water (control). The treatments were applied 3 times, at intervals of 45 days. The variables evaluated were: rate of natural fall (%), fruit length and diameter (mm), and fresh fruit weight (g). None of the treatments promoved alterations in the development of the fruits, but they did reduce the natural fall rate, when compared to control, up to 78.05%, inhibiting the fruits' abscision as much as 3 months.<br>O trabalho objetivou avaliar os efeitos de auxinas e giberelinas, combinados e aplicados em pré-colheita no desenvolvimento e na taxa de queda natural de frutos de laranjeira 'Pêra'. Foram utilizadas árvores de laranjeira (Citrus sinensis Osbeck) cultivar Pêra com 5 anos de idade. Os tratamentos foram: GA3 + 2,4-D 12,5mg L-1 de cada; GA3 + 2,4-D 25mg L-1; GA3 + 2,4-D 37,5mg L-1; GA3 + NAA 12,5mg L-1; GA3 + NAA 25mg L-1; GA3 + NAA 37,5mg L-1; NAA + 2,4-D 12,5mg L-1; NAA + 2,4-D 25mg L-1; NAA + 2,4-D 37,5mg L-1 e testemunha (água). Durante todo o período experimental foram realizadas três aplicações a intervalos de 45 dias. As variáveis avaliadas foram: Taxa de queda natural dos frutos (%), comprimento (mm), diâmetro (mm) e massa fresca dos frutos (g). Nenhum dos tratamentos proporcionaram alterações no desenvolvimento final dos frutos, mas reduziram a taxa de queda natural em comparação com a testemunha em até 78,05%, inibindo a abscisão dos frutos em até três meses