Проблема снижения качества семян конопли посевной и пути ее решения

Abstract

The article presents the results of studies on the influence of damage during combine harvesting and post-harvest treatment on the sowing properties of hemp seeds. It is noted that at combine threshing on the background of increase of mechanical damages in the form of macrotraumas (35%) and microtraumas (22%) there is a decrease in laboratory germination of hemp seeds up to 68%. The main share of macrotraumas is caused by crushing – 8.5%; removal of husk – 10%, as well as cracks in the area of the cotyledon and embryo – 16.5%. Desiccation of hemp crops at combine threshing and subsequent post-harvest treatment reduces macrodamage of seeds by 17% and microdamage by 9%. Indicators of germination energy and seed germination are comparable with similar data from manual threshing and amount to 94% and 95%, respectively. Microbiological analysis of hemp seeds showed significant differences in the quantitative and group composition of bacterial and fungal microflora during combine and manual threshing of seeds. When manually threshed, seeds are dominated by bacterial microflora with a predominance of the genus Bacillus. The fungal microflora is mainly dominated by representatives of the genus Penicillium. Fungal microflora prevails on seeds at combine threshing (310 thousand CFU/g), the main share of which is represented by micromycetes of the genus Aspergillus (120 thousand КОЕ/g) and various yeast species (190 thousand CFU/g), which contributes to the accumulation of mycotoxins and accompanied by loss of seed germination (up to 86%). Application of crop desiccation at combine threshing provides the formation of a microbial community with predominance of micromycetes of Penicillium genus (66%), which allows to keep seed germination at the level of 95% throughout the whole storage period. A significant reserve for increasing the sowing properties of seeds is the desiccation of crops with post-harvest treatment, which reduces damage and ensures the formation of epiphytic microflora, which prevents the development of molds, which negatively affect the sowing properties of seeds.