The photosynthesis inhibitor metamitron is a highly effective thinner for ‘Golden Delicious’ apple in a warm climate

Stern, Raphael A.

doi:10.1051/fruits/2015007

Cited by 31 publications

(21 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Many authors have reported the day of maximum Brevis ® induced inhibition at between 2 and 6 days after application (Brunner, 2014;Rosa, 2016;Stern, 2015). Their results differ from the observations of this study, with maximum inhibition Qy(%) values observed 5-10 days after treatment.…”

contrasting

confidence: 98%

“…Their results differ from the observations of this study, with maximum inhibition Qy(%) values observed 5-10 days after treatment. Moreover, Brevis ® reduced electron transport rates by up to 40%, with similar observations reported by , Stern (2014) and Stern (2015).…”

supporting

confidence: 87%

“…The thinning activity of metamitron in apple is via inhibition of photosynthesis (Basak, 2011;Lafer, 2010). More specifically, it is a photosystem II (PSII) inhibitor that disrupts the photosynthetic apparatus Stern, 2014Stern, , 2015, and acts by blocking electron transfer between the primary and secondary quinones . This interruption of photosynthetic electron transport inhibits adenosine 5´triphosphate production and carbon fixation .…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Effect of different application rates of metamitron as fruitlet chemical thinner on thinning efficacy and fluorescence inhibition in Gala and Fuji apple

González¹,

Torres²,

Carbó

et al. 2019

Plant Growth Regul

View full text Add to dashboard Cite

Crop thinning is an important and difficult agricultural practice. Knowing the effect of the application dose of a product is a crucial element of any thinning program. The aims of this study were to investigate the effect of different metamitron doses on Gala and Fuji apples applied at fruit king diameters of between 8 and 10 mm and to determine fluorescence inhibition at the different application rates. Trials were conducted over two seasons from 2015 to 2016 in apple orchards in Lleida (Spain). Photosynthesis inhibition caused by metamitron was also analysed and measured, using chlorophyll fluorescence and biexponential pharmacokinetic models. Under the trial conditions, the application of metamitron reduced final fruit set, number of fruits per tree and crop load depending on the application rate. A dose effect was observed in all yield parameters. Moreover, when metamitron showed high efficacy, there was an improvement in fruit weight, coloration and diameter. The estimated parameters A, α and B using a biexponential equation were related with final fruit set, however the period of inhibition has to be finished before prediction can be made of metamitron efficacy in the year. The fluorescence analysis showed a dose effect, with metamitron dose increasing inhibition. Additionally, the same result was also observed in the area under curve analysis, with metamitron dose reducing the area and inhibition increasing. In all yield parameters, the fluorescence and area under curve analyses showed differences between cultivars, with the inhibition caused by metamitron higher in Gala than in Fuji. Moreover, differences between years were observed. 2015 was warmer than 2016, and the higher temperatures increased the thinning efficacy of metamitron.

show abstract

contrasting

confidence: 98%

supporting

confidence: 87%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Effect of different application rates of metamitron as fruitlet chemical thinner on thinning efficacy and fluorescence inhibition in Gala and Fuji apple

González¹,

Torres²,

Carbó

et al. 2019

Plant Growth Regul

View full text Add to dashboard Cite

show abstract

“…Single metamitron treatment improved average fruit size and fruit size distribution only when it significantly reduced the number of fruit, regardless of the application time, as similarly noted by Stern (2015). When metamitron application was repeated and it was mixed with other chemical thinners, increments in fruit size and share of the larger fruit in the total yield were regularly noted compared to the unthinned control treatment.…”

Section: Treatmentsupporting

confidence: 60%

Comparison of metamitron efficiency for postbloom thinning of young ‘Gala’ and ‘Golden Delicious’ apple trees

Radivojević¹,

Milivojević²,

Pavlović³

et al. 2020

Turk J Agric For

View full text Add to dashboard Cite

Introduction Establishing new apple orchards using well-feathered apple trees has recently become common practice. In favourable growing conditions, these trees can produce high yield in the second leaf, achieving full productivity in the fourth leaf (Radivojevic et al., 2014). High-quality trees of the cultivars 'Gala' and 'Golden Delicious' during the establishing period frequently produce an excessive number of fruitlets but this can be insufficient to guarantee fruit of good marketable size at harvest (Bregoli et al., 2007). Furthermore, an unwanted excessive number of fruit per tree during that period can reduce the growth of a young tree and delay the achievement of maximum tree size. Because of this, trees require adequate thinning to reach marketable fruit sizes and regular yields by preventing alternate bearing (Maas, 2006). In mature orchards chemical fruit thinning is a major cultural practice (Bound, 2006; Dorigoni and Lezzer, 2007), but in young apple orchards hand fruit thinning is usually done. However, due to the increasing lack of seasonal workers and high labour costs, this job is becoming unrealisable, especially in large areas (Radivojević et al., 2011). Moreover, hand thinning is usually carried out after June-drop, by which time only increases in fruit size are achieved and there is no reduction in alternate bearing (Maas, 2006). Chemical thinning, as compared to hand thinning, is a quick operation and allows thinning fruit at the right moment, guaranteeing better fruit quality and significantly reducing labour costs (Costa et al., 2006). In young apple orchards chemical thinning has to be regularly performed and start in the second leaf, whereby different chemicals can be applied either alone or in combination in order to improve reliability and thinning efficacy (Verjans et al., 2018). Plant growth regulators such as auxins and cytokinins have become essential in commercial apple production (Brunner, 2014; Stern, 2015). However,

show abstract

“…Their leaf AA, TPC and osmolarity were also assessed, in order to identify a possible mechanism for the greater frost tolerance of ‘Ettinger’ than that of ‘Hass’. Measurements of physiological parameters following the controlled artificial frost treatments in the laboratory showed that detached ‘Ettinger’ branches had greater tolerance of the FHL treatment than ‘Hass’ branches, as their visible damage rate was lower and F v / F m rate, a reliable quantitative indicator of frost damage and other stress damage (Rizza et al ., 2001; Ehlert and Hincha, 2008; Stern, 2015), was significantly higher. These results are consistent with previously described frost-hardy characteristics of ‘Ettinger’ trees – descriptions mostly based on growers' observations over the years (data not shown).…”

Section: Discussionmentioning

confidence: 88%

Comparative study of leaf antioxidant activity as a possible mechanism for frost tolerance in ‘Hass’ and ‘Ettinger’ avocado cultivars

et al. 2019

View full text Add to dashboard Cite

A major drawback of avocado (Persea americanaMill.) is susceptibility to frosts, which reduces yields and limits its geographic distribution and market growth. Whereas the frost-susceptible cultivar ‘Hass’ leads the global avocado market, cv. ‘Ettinger’, although commercially less important, is considered frost-tolerant. The mechanism behind the greater frost tolerance of ‘Ettinger’ has not yet been elucidated; therefore, the aim of the current study was to evaluate the differences between the frost responses of the two cultivars. The results showed that detached ‘Ettinger’ branches had greater tolerance than ‘Hass’ to controlled frost stress. Tissue browning caused by methyl viologen oxidative cell damage, superoxide accumulation in leaf discs following wounding and browning of cut surfaces in branches were much lower in ‘Ettinger’ than in ‘Hass’, suggesting greater antioxidant activity (AA) in the former. In leaf extracts, AA was significantly higher in ‘Ettinger’ than in ‘Hass’, but osmolarity was similar in the two cultivars. Total phenolics content was significantly higher in ‘Ettinger’ but addition of a protein mask did not significantly reduce AA in either cultivar. Interestingly, following the freezing treatment, AA increased in ‘Ettinger’ and remained almost unchanged in ‘Hass’, while osmolarity was unaffected in either cultivar. These results suggest that the greater frost-tolerance of ‘Ettinger’ than ‘Hass’ is due largely to its greater AA, which springs mainly from a non-enzymatic source, i.e. accumulation of phenolic compounds. Based on the current study, future applications may be developed to minimize frost damage in avocado orchards.

show abstract

The photosynthesis inhibitor metamitron is a highly effective thinner for ‘Golden Delicious’ apple in a warm climate

Cited by 31 publications

References 29 publications

Effect of different application rates of metamitron as fruitlet chemical thinner on thinning efficacy and fluorescence inhibition in Gala and Fuji apple

Effect of different application rates of metamitron as fruitlet chemical thinner on thinning efficacy and fluorescence inhibition in Gala and Fuji apple

Comparison of metamitron efficiency for postbloom thinning of young ‘Gala’ and ‘Golden Delicious’ apple trees

Comparative study of leaf antioxidant activity as a possible mechanism for frost tolerance in ‘Hass’ and ‘Ettinger’ avocado cultivars

Contact Info

Product

Resources

About