Influence of climate warming on beginning of flowering of apple tree (Malus domestica Borkh.) in Lithuania

D. Romanovskaja and E. Bakšiene

Vok� Branch of Lithuanian Institute of Agriculture, Žalioji a. 2, LT – 02232 Vilnius; e-mail:
danuta.romanovskaja@voke.lzi.lt

Abstract:

The paper presents summarized data of longtime (the period of 1961–2006) phenological observations of apple trees (Malus domestica Borkh.) in Lithuania. It has been determined that in different localities of the country apple trees start flowering on May 11–17 (± 3–5 days); the average in Lithuania is May 16. Evaluation of the changes in the dates of the beginning of apple tree flowering revealed that, due to climate warming during the last decade, apple trees start flowering 4–5 days earlier than the longtime average. The thermal regime of April strongly influences the annual changes in the dates of the beginning of apple tree flowering: the correlation coefficient between the mean monthly air temperature and dates of the beginning of apple tree flowering is -0.48 – (-0.80). The possibility to forecast the dates of the beginning of apple tree flowering based on the dates of the beginning of the flowering of European hazel (Corylus avellana L.) and European bird cherry (Padus avium Mill.) was investigated. It has been ascertained that the date of the beginning of the European bird cherry flowering is suitable for forecasting the date of the beginning of the apple tree flowering because that date significantly correlates with the beginning of the European bird cherry flowering, which is an indicator of true spring.

Key words:

Possibilities of weed control with herbicide Basta 150 SL in a young apple tree orchard

L. Buskienė¹, N. Uselis² and J. Lanauskas²

¹Lithuanian Institute of Horticulture, Kauno 30, LT–54333 Babtai, Kaunas distr., Lithuania;e–mail: l.buskiene@lsdi.lt
²Lithuanian Institute of Horticulture, Kauno 30, LT–54333 Babtai, Kaunas distr., Lithuania;e–mail: institutas@lsdi.lt

Abstract:

The effect of herbicide Basta 150 SL (a.i. ammonium glufosinate) on weed control in a 3–4 year–old apple tree orchard was investigated at the Lithuanian Institute of Horticulture in 2004–2005. Basta 150 SL was applied at the rates 3.0 l ha-1 and 6.0 l ha-1, standard herbicide Roundup 360 SL – at the rate 3.0 l ha-1. Herbicides were applied twice over the growing season: the first application, until beginning of flowering, the second , when weeds had grown to 10–15 cm. Control plots were not treated with herbicides. Apple tree growth, weed species composition, weed number and weed fresh weight were measured.The most effective for weed control were 6.0 l ha-1 of Basta 150 SL and 3.0 l ha-1 ofRoundup 360 SL. They killed respectively 80.4–95.3% and 84.7–87.7% of weeds. Dandelions, (Taraxacum officinale L.), the prevailing weeds , were killed successfully with both herbicides. The lowest weed fresh weight was after 6.0 l ha-1 of Basta 150 SL application – 3.2%. Phytotoxic effect of herbicide Basta 150 SL on apple trees was not observed. When herbicides were applied apple tree shoot length increased by 1.4–1.9 times. Weed fresh weight had higher impact on shoot length than the total number of weeds.

Key words:

apple trees, growth, herbicides, weed biomass, weed fresh weight