Prorjeđivanje plodova jabuke sorte \u27Gala\u27 pomoću ethephona, NAA i BA te njihovih kombinacija

The thinning response was studied on six years old trees of ‘Gala’/M.9. The treatments of single application of ethephon 200 ppm at the balloon stage, of naphthaleneacetic acid (NAA) 10 ppm or benzyladenine (BA) 100 ppm at 10 mm fruit diameter as well as the sequential treatments of ethephon followed by NAA or/and BA and tank mixed NAA + BA treatment were performed. A non significant thinning was obtained in treatments when ethephon, NAA and BA were used separately. No additional thinning occurred even in the combinations when ethephon was applied first at the balloon stage and NAA or BA applied later at 10 mm fruitlet diameter. Significant thinning response occurred only when tank mixed treatment of NAA + BA and sequential treatment of ethephon followed by tank mixture of NAA + BA were carried out. In this experiment, mean fruit weight and the share of bigger sized fruits (>70mm) increased significantly in all thinning treatments compared to the non thinned control trees.Proučavali smo odaziv prorjeđivanja na šest godina starim stablima sorte \u27Gala\u27/M.9. Izvedeni su postupci pojedinačnih aplikacija etefona 200 ppm u fenofazi crvene glavice, naftiloctene kiseline (NAA) 10 ppm ili benziladenina (BA) 100 ppm kada je promjer ploda iznosio 10 mm kao i uzastopni postupci etefonom nakon čega je slijedila NAA, odnosno BA ili u tanku pomiješani NAA + BA. Prorjeđivanje nije bilo signifikantno kod postupaka, u kojima su etefon, NAA i BA primijenjeni pojedinačno. Do dodatnog prorjeđivanja nije došlo ni u postupcima kada je etefon primijenjen najprije u balonskom stadiju, a NAA ili BA primijenjeni kasnije, kada je promjer plodova iznosio 10 mm. Signifikantan odaziv na prorjeđivanje dogodio se samo kada je izveden postupak s u tanku pomiješanim NAA + BA i uzastopni postupak etefonom nakon čega su slijedili u tanku pomiješani NAA + BA. U tom pokusu prosječna težina plodova i udio većih plodova (> 70 mm) signifikantno su se povećali kod svih postupaka prorjeđivanja u usporedbi s neprorjeđivanim stablima kontrole

Prorjeđivanje plodova jabuke sorte \u27Gala\u27 pomoću ethephona, NAA i BA te njihovih kombinacija

The thinning response was studied on six years old trees of ‘Gala’/M.9. The treatments of single application of ethephon 200 ppm at the balloon stage, of naphthaleneacetic acid (NAA) 10 ppm or benzyladenine (BA) 100 ppm at 10 mm fruit diameter as well as the sequential treatments of ethephon followed by NAA or/and BA and tank mixed NAA + BA treatment were performed. A non significant thinning was obtained in treatments when ethephon, NAA and BA were used separately. No additional thinning occurred even in the combinations when ethephon was applied first at the balloon stage and NAA or BA applied later at 10 mm fruitlet diameter. Significant thinning response occurred only when tank mixed treatment of NAA + BA and sequential treatment of ethephon followed by tank mixture of NAA + BA were carried out. In this experiment, mean fruit weight and the share of bigger sized fruits (>70mm) increased significantly in all thinning treatments compared to the non thinned control trees.Proučavali smo odaziv prorjeđivanja na šest godina starim stablima sorte \u27Gala\u27/M.9. Izvedeni su postupci pojedinačnih aplikacija etefona 200 ppm u fenofazi crvene glavice, naftiloctene kiseline (NAA) 10 ppm ili benziladenina (BA) 100 ppm kada je promjer ploda iznosio 10 mm kao i uzastopni postupci etefonom nakon čega je slijedila NAA, odnosno BA ili u tanku pomiješani NAA + BA. Prorjeđivanje nije bilo signifikantno kod postupaka, u kojima su etefon, NAA i BA primijenjeni pojedinačno. Do dodatnog prorjeđivanja nije došlo ni u postupcima kada je etefon primijenjen najprije u balonskom stadiju, a NAA ili BA primijenjeni kasnije, kada je promjer plodova iznosio 10 mm. Signifikantan odaziv na prorjeđivanje dogodio se samo kada je izveden postupak s u tanku pomiješanim NAA + BA i uzastopni postupak etefonom nakon čega su slijedili u tanku pomiješani NAA + BA. U tom pokusu prosječna težina plodova i udio većih plodova (> 70 mm) signifikantno su se povećali kod svih postupaka prorjeđivanja u usporedbi s neprorjeđivanim stablima kontrole

Diagnostics of fruit trees phytoplasmas – the importance of latent infections

In the period 2000-2008 more than 1300 fruit trees from different regions of Slovenia were tested for the quarantine phytoplasmas Apple proliferation (AP), Pear decline (PD), and European stone fruit yellows (ESFY). The majority of samples were collected within systematic official surveys, which was conducted for assessing the presence of these phytoplasma in Slovenia in production and mother plant orchards. Samples were taken from trees with and without expressed symptoms. DNA was extracted from the symptomatic shoots. In addition some roots from asymptomatic trees were sampled for the evaluation of latent infections. The presence of phytoplasmas was analyzed with a nested PCR, RFLP and a real time PCR (Hren et al., 2007). AP, PD and ESFY were confirmed as being present in several areas in Slovenia where fruit trees are cultivated. AP was found not only in apple, but also in stone fruit trees such as cherry, apricot and plum (Mehle et al., 2007). By using highly sensitive diagnostic methods, such as real time PCR, some latent infections were detected and they were confirmed next year also by less sensitive methods.Keywords: Phytoplasma, AP, PD, ESFY, latent infection, fruit tree