Determination of Survival and Restoration Ability of a Soybean Stand on a Natural Background of Weed Infestation
AbstractThe study was carried out during the 2002–2004 period in the Instituteof Forage Crops – Pleven, branch Pavlikeni. The objective of the study was todetermine survival and reproductive ability of soybean under a mixed type ofweed infestation depending on environmental agro-climatic conditions. Theweed infestation in the studied agrophytocenosis varied of 61.5 tо122.6 plants/m2, with predominance: Amaranthus spp., Solanum nigrum (L.) and Sorghumhalepense (L.) Pers. Survival ability (lx) of soybean plants grown on a naturalbackground of weed infestation till technical ripeness of the crop was withinthe range of 0.76 tо 0.96 and depended on the degree of weed infestation of thestand and rainfall amount. Soybean grown on a natural background of weedinfestation under the conditions of the study had relatively good restorationability (R) varying from 1.16 tо 5.09.
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