ЛИСТОВОЙ ФОТОСИНТЕТИЧЕСКИЙ ПОТЕНЦИАЛ АГРОЦЕНОЗА ТОПИНАМБУРА

Abstract

In Russian Non-Black Soil Zone, plantings of Jerusalem artichoke are capable of forming a powerful foliar photosynthetic potential in any year. However, it reaches its highest value in warm, humid years (on average, according to the experiment, 5.2–5.9 million m2 x day/ha) when 1/3 of the calculated NPK dose per yield is 400 c/ha. Higher yields of biomass, on average, in 1 year of use (502–508 c/ha), it accumulates with a foliar photosynthetic potential of 3.7–4.1 million m2 x day/ha, and in the second year (366–368 c/ha) – 2.6–2.7 million m2 x day/ha. The accumulation of the phytomass crop in Skorospelka Jerusalem artichoke variety is important not only for the total power of LFP, but also for the course of its formation during the growing season. In the studies at the Tver State Agricultural Academy, the largest part of the LFP was created during 80 days of vegetation, 40 days after germination, with a maximum within 40 days, 60 days after germination. This coincides with the period of mass plant budding. It has been proved that the formation of an excessively large foliar area of Jerusalem artichoke agrocenosis is not accompanied by an increase in yield. In humid warm years (2006), higher yields in 1 year are formed with such graphs of growth of the Jerusalem artichoke foliar area, when on the 20th day it reaches the level of 40 thousand m2 /ha, on the 40th – 70, on the 60th – a maximum of 82 thousand. m2 /ha, at the level of 60 thousand m2/ha it remains for another 50 days, and before harvesting it decreases only to 46 thousand m2 /ha. In dry warm years (2007), high yields of tubers (343–348 c/ha) in terms of organic or mineral background accumulate at lower parameters of the foliar area with maxima of 32–42 thousand m2 /ha, while maintaining such sizes for another 20–30 days, and for harvesting – 14–15 thousand m2 /ha. In wet cold years (2008), higher yields of biomass are formed when it reaches a maximum of 50–53 thousand m2 /ha on the 60th day, remains in this state for another 20 days, then decreases to 31 and by harvesting – 14.6 thousand m2 /ha.