The yield, height and content of protein of field peas (Pisum sativum L.) in Estonian agro-climatic conditions

M. Olle

Estonian Crop Research Institute, Department of Plant Breeding, J. Aamissepa 1, EE48309 Jogeva alevik, Estonia
Correspondence: margit.olle@etki.ee

Abstract:

Pisum sativum L. is important protein crop in the world. The purpose of this investigation was to see whether pea varieties differ in their yield, height and content of protein. Another aim was to select the best varieties suitable for production. Field experiments with different varieties of peas (‘Bruno’, ‘Capella’, ‘Clara’ and ‘Vitra’) were carried out at the Estonian Crop Research Institute in 2014 and in 2015. Yields (t ha^-1) in 2014 and 2015 did not differ much, while yield from variety ‘Bruno’ was very different between years 2014 and 2015 and was much higher in 2015. The most suitable height of field peas is in a range of 60…100 cm, because the plants with such a height are most effectively suppressing weeds. It can be concluded that varieties with suitable height in our investigation were: ‘Bruno’, ‘Capella’ and ‘Clara’. Variety ‘Vitra’ was too high, is lodging easily and is therefore hard to harvest. Crude protein content (% in dry matter) was lowest in ‘Clara’; all other varieties had a higher content of protein, within much the same range. Based on the results of present investigation it can be concluded that out of those four varieties the most suitable varieties for production are ‘Bruno’ and ‘Capella’. Choice of the right variety for pea cultivation is very important, but depends on the local agro-climatic conditions. As in Baltic – Nordic countries and in north of America the agro-climatic conditions are more or less similar the results are useful for those countries.

Key words:

Productivity of poplar hybrid (Populus balsamifera x P. laurifolia) in Latvia

A. Jansons*, S. Zurkova, D. Lazdina and M. Zeps

Latvian State Forest Research Institute ‘Silava’, Rigas 111, LV-2169 Salaspils, Latvia; *Correspondence: aris.jansons@silava.lv

Abstract:

Fast growing poplar clones have been widely used for biomass production in Southern Europe; however, there is insufficient information about the growth of poplar in north-eastern Europe that might hamper its wider use. The aim of the study was to assess the productivity of poplar hybrid and its potential for biomass productions. Material for the study was collected in 14 stands (age 54–65 years) located in the central and western part of Latvia (56–57°N, 22–23°E), which were established on fertile drained mineral soil (Mercurialiosa mel.) and mineral soil with normal moisture regime (Oxalidosa and Aegopodiosa). Tree diameter and height were measured and biomass was estimated using equation developed based on 24 sample trees. Mean tree diameter and height in stands on mineral soil varied greatly (from 29 ± 1.6 cm to 45 ± 3.9 cm and from 24 ± 0.9 m to 31 ± 0.8 m, respectively); however in stands on drained mineral soil mean diameter and height was 42 ± 2.1 cm and 27 ± 0.7 m, respectively. Mean diameter and height of poplar was 16.7–25.1% higher compared with Norway spruce and these differences were statistically significant (p-value < 0.05), differences with common aspen were not significant. The number of fallen and standing dead trees, reaching up to 14–46% from the number of living trees, indicated aging and intense self-thinning. Mean annual volume increment of all stands was 11.8 m3 ha-1 y-1 (in some of stands reaching 21.0 m3 ha-1 y-1), corresponding to 4.2–9.8 t of dry matter per year. Thus, the results suggest that poplar could be an efficient species for production of bioenergy.

Key words:

diameter, height, Salicaceae, yield