Avaliação de híbridos de pepino tipo japonês sob ambiente protegido em duas épocas de cultivo

Abstract

Evaluation of "japanese" cucumber hybrids under protected cultivation in two sowing dates Twelve cucumber hybrids were evaluated in summer (two replications of seven plants) and fourteen in autumn-winter (four replications of five plants), in a randomized block design to evaluate their performance under protected cultivation at Sao Manuel, São Paulo State, Brazil. Only 'Rensei' was ginoiceous, while the others (AF-1327, AF-1328, AF-1329, BU-92, Hokuho, Hokushin, Hyuma, KH-705, Natsusuzumi, Nikkey, Summer Green, Top Green, Tsuyataro and Yoshinari) were monoiceous, although all of them were partenocarpic. The most yielding hybrids in summer were Tsuyataro (25,4 fruits/plant) and Rensei (25,3 fruits/plants). The most yielding in autumn-winter were 'Nikkey' (26,8 fruits/plant) and 'Top Green' (23,4 fruits/plant) and the least yielding were 'Rensei´(16,1 fruits/plant) and AF-1328 (17,6 fruits/plant). Higher yieldings were obtained in autumn-winter sowing than in summer.

Performance of advanced generation from a hybrid Japanese cucumber

“…Cardoso & Silva (2003) obtained, on average, larger production in the hybrid (Tsuyataro, from Takii company) with larger percentage of lateral stems.…”

“…An average of 35.5 days was obtained after the transplant for the crop, a value similar to the 33 days obtained by Blanco et al (2002). On the other hand, Cardoso & Silva (2003), studying a different japanese hybrid, obtained 72 days after the sowing in autumn -winter cultivation. However, for the summer cultivation the harvest began 47 days after the sowing.…”

“…Cardoso & Silva (2003) obtained 33 and 20 fruits/plant in the evaluation of hybrids of Japanese cucumber in winter and summer cultivation, respectively. Fernandes et al (2002) obtained 920 g per plant in nutrient solution.…”

“…Although the inbreeding depression is a consequence of an increase of the homozygous, its magnitude depends on number and types of deleterious genes, exposed to conditions of homozygosis (Charlesworth & Charlesworth, 1979). The influence of inbreeding is thoroughly different among species (Byers & Waller, 1999;Husband & Schemske, 1996).…”

Enhanced production of parthenocarpic cucumbers pollinated with stingless bees and Africanized honey bees in greenhouses

“…The parthenocarpy trait makes crop production possible in greenhouses, in places where there is a shortage of pollinators and in scenarios where there is inadequate synchronization between male and female flowers (CARDOSO;SILVA, 2003). Some environmental factors, such as short days and low nighttime temperatures, stimulate the formation of parthenocarpic cucumber fruits (FERRI, 1979).…”